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THE GULF OF MAINE TERN MANAGEMENT PLAN

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CONTENTS

PREFACE

NATURAL HISTORY OF TERN SPECIES BREEDING IN THE GULF·OF MAINE

JUSTIFICATION for a Tern Management Plan: Tern Populations and Population Changes

· --- - Causes of Population Declines

GOALS for a Tern Management Plan: Increase the Abundance and Expand the Distribution of Terns

OBJECTIVES for the Northwest Coast of the Gulf of Maine:

1) Restore popu.~ations or terns to the levels or the 1930s ~ Arctic Terns: 8,000 pairs, including 2,300 pairs on Machias Se~ Is. Common Terns: 8,000 pairs, including 1,700 pairs on Isles of'Shoals Roseate Tern; 275 pairs.

2) Expand the numbers and distribution of productive colonies based in part on historical patterns:

Arctic Terns: 10 colonies; Common Terns: 25 colonies; Roseate Terns: 3 colonies.

MANAGEMENT OUTLINE

I. Monitor Abundance, Distribution and Productivity

- II. Plan and Implement Management Actions

III. Conduct Studies to Guide Management Programs

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~ APPENDICES

A. TABLES: CENSUSES OF TERNS, CAPE ANN TO GRAND MANAN 15

B. TABLES: HERRING GULl.S Differences in Breeding Success in Herring Gulls 18 Movements of Herring Gulls among Breeding Islands Changes in Numbers of Gulls and Terns Man and Medric

C. ISLANDS .REPORTED TO BE NESTING SITES FOR TERNS 23 Summary List of Maine Islands Maine Islands Reported as Nesting Sites by Norton 1880-1920 30

D. SUGGESTIONS FOR FIElD PARTIES 44 -Recommended Procedures For Censusing Terns Recommended Proce\Jures ForMeasuring Breeding Success \

E.MANAGEMENTPROCEDURES 48

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PREFACE

In the early years of European settlemen~ seabirds were freely exploited in New England and Atlantic Canada, and by the mid-nineteenth century this pressure had resulted in the extirpation of several species from the coast and the drastic reduction in numbers of many more. At the end of the nineteenth century plume hunting for the millinary trade nearly delivered the coup de &race. Terns were almost complete­ly eliminated from much of the eastern seaboard, including remote parts of the Maine coast.

Growing public concern led to a number of local initiatives to preserve the small populations that remained. In 1916, the U.S. signed the Migratory Birds Convention with Mexico· and Great Britain, on behalf of Canada, with the purpose "of saving from indiscriminate slaughter and of insuring the preservation of such migratory birds as are either useful to man or are harmless." The Migratory Bird Treaty Act of 1918, implemented the Conventions, establishing Federal responsibility for protec­tion of migratory birds. Since then, many species of seabirds which had previously been over-exploited, ·have increased in numbers. During the last several decades, however, tern numbers have d~crease~ and several private orgamzatfons and publ\c agencies have ta.ken steps to halt the decline. .

Gulls and terns, like seaducks on the bays and the songbirds in tlte spruce trees, are important symbols or the natural environment or the G~lf or Maine. Visiting touris~ see landscapes and seascapes in terms or movement, as gulls Dy aner a lobsterboat or terns hover over a riptide. Many or the tourists have a highly sophis­ticated appreciation for the state's nying wildlire, and any diminution or these ele­ments would degrade their experience. Tourism contributes importantly to the economic survival Qf island communities, making it possible Cor many families to stay on the coast who would otherwise have to move inland or to cities to find work.

Because many readers of this management plan will not be familiar with terns and "tern problems," we include a description of the species and a brief history of major features of the population changes iii the Gulf of Maine.

This plan was prepared by members of the Gulf of Maine Tern Working Group, including representatives of Audubon Society of New Hampshire, Canadian Wildlife Service, College of the Atlantic, Island Institute, Maine Audubon Society, Maine

-Department of Inl~nd Fisheries & Wildlife, National Audubon Society, U.S. Fish & Wildlife Service.

The plan includes contributions by the following biologists: John Anderson. - Ralph Andrews, Jane Arbuckle, Tom Goettel, Anthony Lock, Sephen Kress.

The report was prepar~d and edited by William Drury and Scott Melvin.

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NATURAL HISTORY OF TERN SPECIES BREEDING IN THE GULF OF MAINE

Gulls and terns, together, form the family Laridae within the order Charadrijfor­m.cs.. Terns are slender, short-legged birds with long-pointed wings. The sexes are alike and the adults are white with grey wings and back. The beak and legs are usual-ly red, orange or yellow. They feed by diving from the air to catch small fish or crus­taceans near the surface. Terns lay one to three eggs, characteristically in rudimentary nests on shingle, sand or matted vegetation. The incubation period of

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the Maine species is between three and four weeks and chicks fledge at about one month. They typically reach breeding age at two or three years but do no t reach peak . • breeding success until they are more than five years old (1.C.T. Nisbet; pers comm.). Adult mortality is low and they have a long reproductive life, up to 15 to 25 years.

Five species of terns breed in Maine. The Black Tern (Cblidonjas nj~er) breeds only on fresh water, and its status is not known. The Least Tern (Sterna albifroos) -breeds on sandy beaches in southwestern Maine, where it is especially vulnerable to disturbance by bathers, picnickers and their pets. The Maine Audubon Society has undertaken a program to protect all the nesting sites of this species in Maine. The species is widespread and-numerous ~n the sandy shores of Massachusetts and fur- \ ther south.

The three species of marine terns include Arctic Tern (Sterna 'paradjsea) and Common Tern (Sterna bjrundo), which are widespread, ancl ·Roseate Tern (Sterna dou~am) which breeds in small numbers at a few sites. -

ARCTIC TERNS breed as far north as 80 degrees North Latitude and as far south as Massachusetts. They are the most pelagic of our nesting terns, migrating far out to sea, crossing the Atlantic in the autumn, towards the Azores and Cape Verde Islands, and wintering along the edge of the ice pack in the A!_ltarctic. In the north­ern parts of their range Arctic Terns nest in small numbers, often only a few pairs together, or solitarily at inland lakes, ponds anaon the shingle Qn deltas of arctic rivers. In the subarctic part of their nesting range,' they breed, often in large num­bers, in mixed colonies with other terns. They place their nests among rocky out­crops where fescue grass is short enough to allow this bird with very short legs to move about. or on shingle or sand beaches. Their clutch size is one or tWo eggs, sel­dom three, laid in late May or early June. The chicks are flying by late July and migrate directly offshore in early to mid August.

Arctic Terns nest in large numbers on outer islands in eastern Maine as far west as Matinicus Rock, where the cold water flowing out of the Bay of Fundy turns off­shore. They nest in much smaller numbers on islands further west. like Eastern Egg Rock in Muscongus Bay and Stratton Island in Saco Bay.

During the last 75 years the major colonies of nesting terns have been on islands with lighthouses manned by keepers ·and their families: Machias Seal. South Libby, Petit M:s:nan, and Matinicus Rock. The lighthouse keepers kept marauding gulls away froiii the nesting terns. Where there were no lighthouses or keepers, as on is­lands like Metinic Green in the Approaches to Penobscot Bay, gulls drove terns off

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by the 1920s. Herring Gulls moved in and terns soon abandoned the island after the lighthouses on South Libby and Petit Manan were abandoned.

Arctic Terns have more slender and relatively longer wings than Common or

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Roseate Terns. ·Their head protrudes only a short way in front of their wings and ___ _ _ their long tail streams behind. When hovering over an intruder they "face yo~ head on," as if using binocular vision, unlike the other species. Their light flight is suitable for skimming and clipping small items of food, such as yearling herring (Brit), white hake and crustacea, from the surface or close under the surface.

COMMON TERNS breed from North Carolina north to Hamilton Inlet, Labrador. They are less tied to the sea than are Arctic Terns, breeding on many fresh water rakes, including the Great Lakes and as far northwest as Great Slave Lake. Common Terns may breed in small colonies or solitarily on inland lakes, while their marine colonies may be very large. In Maine Common Terns nest in large num­bers on Petit Manan, (and have done so periodically on Metinic, Large Green and Eastern Egg Rock), but mostly in small numbers on islands near the mainland shore: Stratton Island, North Sugar Loaf, Killick Stone, The Brothers at Port Clyde, Tommy Island in Muscle Ridge, Thrumcap in Broo~lle, and Smultynose between Blue Hill and Jericho Bay. Their wings are broader than those of Arctic Terns. 1)ieir protrud­ing head and longer bill seem to suit them for diving after larger fish than those sought by Arctic Terns. .

Their relatively long legs allow them to move around in taller grasses found on the middle and inner islands in mid-coast Maine. They prefer to nest in bare patches in relatively thick stands of grass. They lay a clutch of two or three eggs, which is con­sistent with their commuting relatively short distances for food and having access to relatively .large prey. They lay in late May and early June and the southward migra­tion begins in early September. Common Terns migrate southward close to shore toward their wintering range from Florida and the Caribbean Sea south to Brazil.

The populations of Arctic Terns and Common Terns in Maine are not in danger of extirpation at present; they are classified as Species of Special Concern in Maine by the MDIF&W, but that of Roseate Terns is.

ROSEATE TERNS have a wide breeding distribution across temperate and tropical r~ions, including northwest Europe and southeast Australia Everywhere they occur it is in small numbers. Maine is near the northern limit of their breeding range. Most Maine birds nest at Petit Manan. though they have nested in the past in numbers at North Sugarloaf in the mouth of the Kennebec River, and at Stratton Is­land in Saco Bay: They nest in colonies of other terns, primarily Common Terns.

Their relatively short wings, long tail and fast, steady flight allow them to com­mute long distances (up ·10 15 or 20 miles) to feed. Their wings make it difficult for them to liover over their prey as long as Common and Arctic Terns. They dive espe­cially deep from higher in the air than do the other species. They feed over tide rips or places where fast currents flow over over shallow bars, making small fish vul-

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nerable. They appear to be limited to places that have bars like those between Petit Manan and Petit Manan Point, between Bar-Trumpet-Ship islands and between Great Gott and Mount Desert islands in lower Blue Hill Bay. The lack of suitable, shallow bars elsewhere in Maine may be a rcasonJhat..Ro.seate Terns arc rare.

Their relatively long legs facilitate their moving around in coarse vegetation, under which they prefer to.·nest, e.g. Seaside Goldenrod (Solida~o sempervirens), coarse Umbellifers (Seaside Angelica (Coelopleurum lucidum), Scotch Lovage (Lj~sticum scothicum), and Beach Pea (Lathyrus maritjmus). They lay two eggs and seldom raise more than one chick, which is consistent with their commuting rather long distances to forage. - - •

Roseate Terns practice piracy. Such birds "hang on," like a hunting Peregrine, flying back and forth at about 30 feet above the milling terns flying to and from a temery. The pirates dive on a tern flying in with a fish or on a parent just feeding a chick, surprising the victim, and fly off with the fish to their own young.

They winter on the Atlantic coasts of the Caribbean Sea south to Brazil. They are nowhere numerous, and the recent decline has resulted in their being officially listed as an Endangered Species by both the U.S. Fish & Wildlige Service and the

' Maine Department offnland Fisheries and Wildlife.

JUSTIFICATION FORA TERN MANAGEMENT PLAN

In contrast to many other seabirds, terns were apparently not seriously reduced untill the last quarter of the nineteenth centu.ry, when gunners found a market for the wings and whole skins of gulls and terns in the millinery trade. Thk led to a cam­paign of shooting adults on nesting islands between Saco Bay and Isle au Haut.

Once terns breeding in North America were prote~~~ under the Migratory Bird Treaty Act, they responded quickly to protection. The terns-nesting in Maine, for ex­ample, are estimated to have increased by 2:5 times, from al?out 6,500 pairs at the end of the nineteenth century (Dutcher, 1905) to nearly 16,000 pairs in the 1940's (Palmer, 1948). For the entire New England Coast, the increase was from about 22,000 of all three species about 1900 to about 58,000 in the 1940s (Nisbet, 1973). In the same period, gulls in New England increased by 10 times, from 10,000 to 100,000 breeding pairs (Drury, 1973-74).

The population explosion of Herring and Great Black-backed Gulls seems to have been caused by human activities, primarily large-scale disposal of garbage at urban dumps and gurry thrown over the side from fishing vessels. The increase in gull numbers triggered a second important decline in tern numbers starting in the· · 1940s.

Gulls compete with terns for desirable breeding habitat and they prey on tern eggs and chicks. The effects of gull predation caused comment by Arthur Norton as early as )_924 (Maine Naturalist, 1925). From an estimated 8,000 Common Terns (including·1700 pairs at Isles of Shoals) and 8,000 Arctic Terns (including ~00 pairs at Machias Seal Island) in the mid 1940s in Maine and nearby waters, numbers fell to

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2,100 Common Terns (none at Isles of Shoals) and 3,250 Arctic Terns (1,600 at Machias Seal Island) in 1977. Private groups undertook to stop the decline in 1984. Yet the 1989 estimate of 2, 700 Common Terns (Kress and Borzik, 1989) (within the probable sampling error of previous cenuses) indicates that there has l>een_littlej{. any recovery in the past 12 years, despite a large increase south of Cape Cod. Moreover, 85% of the surviving terns nested on four islands (Machias Seal, Petit Manan, Matinicus Rock and Eastern Egg Rock) and nearly all successful reproduc­tion took place on these four islands. While Arctic Terns occurred in large numbers on all four islands, Common Terns occurred in large numbers on only two. The small numbers of Roseate Terns were similarly restricted to two islands. This situation makes them .especially vulnerable to disturbance.

Recently, convenient and powerful outboard motors have given people summer access to islets where terns formerly bred. The disturbance by visitors may displace terns to less desirable breeding sites, or facilitate predation by gulls. The loss of any of these remaining breeding sites to predators and incompatible coastal development could seriously reduce the promise of their long-term survival. We believe there is an immediate . need to supply additional island breeding sites, because several b\mdred pairs of terns have been moving-among ndting islands during the last five years, chivied off by predatory gulls. Meanwhile their breeding attemp~ have failed.

Preservation of Viable Populations of Terns will Require 1) regular monitoring of tern and other seabird numbers; 2) long-term active management · to ensure the availability of predator-free is­

lands having suitable nesting habitat Ecological requirements for successful reproduction indicate that these must be distributed near to or on the islands that were major centers of tern nesting when terns were free to nest where they preferred (see Table 1 & Map 1);

3) research assessing the efficacy of monitoring and management techniques, and­evaluating the suitability of nesting sites and habitats available on islands that might possibly be occupied by terns.

Tern Populations and Population Changes

Census Methods The numbers of colonial nesting seabirds are usually easily estimated when they

are concentrated at nesting sites. Terns persistantly nest at some islands over many years so that the birds at some substantial colonies can be readily counted, which makes the task easier. But the task may be made harder by the behavior of birds that nest at many small colonies or as isolated pairs. The unpredictable movements of some of thc . ..;e birds from one colony to another may cause large annual variations in the size of small colonies, independent of overall population changes.

Beca315e terns exhibit both extremes, strong colony site fidelity and readiness to move, cerlsuses of sample colonies may not reflect the tru~ changes in numbers. H numbers arc increasing and colonies proliferate rather than individual colonies in-

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creasing in size, or if numbers are decreasing because sub-optimal colonies disap­pear, spot censuses will miss important data on general population trends. This is likely to happen because larger colonies appear to be tolerant of disturbance, and persist despite it. Small ~oJo~~,_p~cularly, may persist for only a few years and if they are disturbed early in the breeding season the birds may abandon the site and move to another island. Tern populations can be monitored with confidence only by visiting all potential nesting sites in the area.

Causes of Population Declines •

a. Problems on the Breeding Range The two most important negative effe~ on terns during the 'breeding season are

gull competition & predation, and human disturbance.

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As gull populations increase, nesting birds displace terns fr.om some breeding sites because the gulls settle on the breeding sites earlier than do terns, and preempt desirable habitat. During range expansion gulls often settle first on outer islands and then abandon those (see Appendix B, Drury in press) to move onto islands close to the ·Ifiainland coast, where they suffer from predation by Raccoons, Foxes,Minks, Crows, Great Homed Owls and Black-crowned Night Herons. The predators not only kill adults and chicks but also cause incubating adults to abandoI1 their nests at --­night, leading to reproductive failure as the tern eggs and c~cks die of exposure. Meanwhile the movements of gulls away from outer islands leaves a small number of

- gulls excluding terns from nesting on what were important tern-nesting islands. The effects of gulls are not confined to displacement from desirable nesting sites.

Gulls also prey on tern eggs and chicks, and occasionally on adult terns. Human disturbance of nesting islands exposes the eggs and young to intolerable

heat on hot days or to chilling on cold, rainy days. The most damagi.ng effects of human disturbance of tern colonies may be making them subject to increased gull predation because some gulls are attracted to the disturbance and will take ad-vantage of the absence of the parents. ·

b. Problems on the winter range Common Terns and Roseate Terns breeding in New England and Atlantic

Canada migrate along the coast to wintering grounds in the Caribbean Sea and coasts of Central and South America. In these regions they are exposed to market hunting and chemical contamination (Nisbet 1981, 1984 and pers comm., Andrews, et al. 1989). Human predation has been identified as an important factor in the decline of Roseate Terns and it is probably important for Common Terns aISo (Nisbet 1981, 1984). There are some indications that terns wintering in the tropics occasionally find that food is in short supply.

Arctic Terns, in contrast, migrate off shore, to the upwellings off the West African Coast (R.G.B. Brown, pers. comm.) where they may occasionally be snared by fisherifien (S. Kress, pers. comm.). Thence they migrate southward over the productive Benguela Current to winter along the edge of the Antarctic icepack,

where, according to D. Parmelee's and D. Ainley's studies on the Antarctic Ice-front, they have access to abundant food.

The populations of Common Terns and Arctic Terns arc not in imminent danger of extirpation in Maine at present, but four problem5-are-iiilmediately pressing:

i. eighty-five percent of the terns nest in 4 colonies; ii. two-thirds of the Maine population of the nationally

endangered Roseate Tern nest on one island; iii. 600-900 pairs of Common Terns in the mid-coast region have

repeatedly suffered breeding failure due to lack of a suitable nesting island.

iv . no significant reproductive success has b~en reported from any tern colony between Muscongus Bay and Cape Ann, Massachusetts.

The following management plan provides an outline of the tasks proposed to re­store tern numbers to levels approximating those reached during the last period of populati~n growth. We know thatrecovery will not happen ~y itself. During a short period of hands-off protection in the late 1970s, gulls overran the terns nesting at Petit Manan. The terns promptly responded to our intervention by returning to the island. We also know that the mere presence of terns nesting on an island is not enough; our measurements show that the terns nesting on al.inost all islands that are not being managed suffer almost total breeding failure.

These objectives include Machias Seal Island in the Grand Manan Archipelago, through the cooperation of the Canadian Wildlife Service.

References

Andrews, R., G. Atwell, B.G. Blodget, l.C.T. Nisbet, M. Scheibe!. 1989. Roseate Tern Recovery Plan, Northeast Population. Unpubl. Report, Region 5, U.S. Fish & Wildlife Service, Newton Comer, Ma. 02158.

Drury, W.H. 1973-74. Population Changes in New England Seabirds. -Bird Banding 44: 267-313; 45: 1-15.

Nisbet, I.C.T. 1973. Terns in Massachusetts: present numbers and historical chan­ges. Bird Banding, 44: 27-55.

Nisbet. I.C.T. 1981. Biological characteristics of the roseate tern Sterna dou2allij in North America and the Caribbean. Unpublished report to the U.S. Fish & Wildlife Service, Newton Comer, Ma.

Nisbet, l.C.T. 1984. Migration and winter quarters of North American roseate terns as shown by banding recoveries. J. Field-Omithol. 55:1-17.

Palmer, R.S. 1948 The Birds of Maine. Museum of Comp Zool. Cambridge, Mass. :-:-::.

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GULF OF MAINE TERN MANAGEMENT PLAN for the Gulf of Maine Tern Working Group

GOALS: Increase the Abundance and Expand the DistribuUon of Terns

MANAGEMENT OUTLINE··

I. MONITOR ABUNDANCE, DISTRIBUilON AND PRODUCTIVITY. 1. Monitor numbers oftems at known nesting islands;

·- - 2. Estimate breeding success at major colonies (200 or more pairs).

II. PIAN AND IMPLEMENT MANAGEMENT ACTIONS:

OBJECTIVE 1)-Restore populations oftems to the levels of the 1930s Arctic Terns: 8,000 pairs, including 2,300 pairs on Machias Seal Is. Common Terns: 8,000 pairs, including 1,700 pairs on Isles of Shoals Roseate Terns; T/5 pairs.

1. Contpiue current intensive manag~ment to maintain an~ increase -----­numbers at existing succe~stul colonies;

2. Manage vegetation and mineral soil to create suitable nesting sites. 3. Mitigate factors negatively affecting tern numbers, distribution or

reproduction. _ · 4. Discontinue management if criteria indicate.

OBJECTIVE 2) Expand the number or islands available tor terns to nest using historical records of former geographic distnbution:

Arctic Terns: 10 colonies; Common Terns: 25 colonies; Roseate Terns: 3 colonies. (Appendix A: Table 1, Appendix C., & Map 1)

Identify additional islands to be intensively managed. 1. Insure adequate regional distribution. 2. Use criteria in choosing specific islands.

ill. CONDUCT STUDIES TO GUIDE MANAGEMENT PROGRAMS: 1. Investigate the effects of predators and competitors at the major tern

nesting sites; 2. Investigatefactors·arrecting the numbers and distribution of small

colonies, and the causes otrailure where breeding fails chronically; 3. Refine survey techniques; 4. Investigate techniques for manipulating vegetation; S. Make general studies or breeding biology; 6. Survey the distribution and abundance of Gulls.

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Purposes of the Management Plan:

Our intention is to reverse population declines that occurred between 1950 and 1980. This dec~e ~ prllI!_arily the result of human-induced environmental effects · resulting in the increase of Herring and Great Black-backed Gulls. Our recent ex­perience indicates that the decline reflected breeding failures caused by gull preda­tion on adults, eggs and chicks. Many terns in this period moved about among several islands in groups of 50-300 birds, occasionally having some temporary breed­ing success, but mostly failing annually (See Appendix A; Table 3).

Palmer (using Norton and Allen, 1931, and additional information from 1936) reported: Common Terns - 8,899 hll:ds. in 25 colonies;

Arctic Terns - 11,940 birds.in 10 colonies; Roseate Terns - 553 hlrds in 3 colonies. In 1972, Drury, using additional information pr.ovided by Ralph Palmer, es-

timated that the total in the early 1940s was about: Common Terns - 8,000 p.air,s. (including 1,700 at Isles of Shoals), Arctic Terns - 8,000 pairs (including 2,300 at Machias Seal Is.), Roseate Terns '\275 pairs. (Appendix A; Table 2). \

We believe that to ensure healthy populations for the future it is imi)ortant to re­store a more dispersed geographic distribution or terns as well as increasing the population levels. Currently 85% or successful tem nesting oc~rs on just four is­lands. A dispersed geographic distribution and redundancy of suitable nesting sites will minimize the possibility or either continuing attrition, or a single catastrophe eliminating a major population from the coasL We believe that we have suitable sources of information for this part of the management program in the islands listed by Arthur Norton as occupied between 1880 and 1916, together with the list reported by Robert Allen and Arthur ~arton (1931 ).

The proposed task ·under Objective 2., to establish a dispersed distribution of nesting islands implies maintaining one or more colonies in the following regions (Appendix A & C. and Table 1.), listed by Norton and Allen.

a. southern Maine (Isles of Shoals, to Saco Bay and Cape Elizabeth); b. Casco Bay; -c. Small's Point to Damariscove Is., including the Kennebec River mouth; d. Muscongus Bay; - . _ _ ______ _ e. The Approaches to Penobscot Bay (including islands in the

·Muscle Ridge Channe4 Matinicus Rock. Wooden Ball and Seal Island); f. northeastern Penobscot Bay; g. islands in the approaches to Jericho Bay and Swans Island; b. upper Jericho Bay and lower Blue Hill Bay;

· -· -- --i. .Petit Manan j . Machias Bay.

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The species and population sizes in these regions will vary according to the area of foraging grounds, and quantity and quality of food resources. The food resources will vary from year to year.

MANAGEMENT PLAN ..

I. MONITOR ABUNDANCE, DISTRIBUTION AND PRODUCTIVITY Identify and Enhance Positive Factors Affecting the Species Numbers;

1~ Moii'itor numbers or terns at known nesting islands;

Estimate numbers present between 12-22 June. a use mark-recapture method to get an index of nests at major colonies

(those with more than 200 pairs or those occupied by field party). b. estimate numbers of birds in the air or count nests at small colonies. c. estimate the percentage of Arctic to Common Terns by taking

repeated samples of the identity of b~ds in the air in several parts of the nC$ting area. . . ..

. \ . \ . Coordinate plans for these surveys at pre-season meetings (February/March);

compile results and review findings of the effectiveness of management with field workers at post-season meeting (August). Consult suggested census techniques in AppendixD. ·

2. Estimate breeding success at major colonies(> 200 pairs). a . Where possible, determine fledging success (to the age of 15 days)

of marked nests, (identified to species) in sample plots each including 10-15 nests so that 5-10% of the total in the colony are sampled. Plots should be dispersed over the nesting area and monitored annually. •(Pens/exclosures that control the·movements of chicks may be appropriate at some colonies but not at others. See m page 9) Studies are needed to determine the effectiveness of enclosures in measuring breeding success.

b. Alternatively, i. estimate the numbers_of_pairs present in June. ii. estimate the proportion of Common and Arctic terns and count the Roseate Terns presenL iii: visit the island in mid- to late July to count the chicks that gather on the beaches either from a boat or from the beach. In some cases a telescope will.be needed to collect this information.

Absence of either adults or young on a July visit is evidence of breeding failure.

See suggested methods of measuring breeding success in Appendix D.

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II. PLAN AND IMPLEMENI' MANAGEMENT ACilONS

OBJEcnvE 1. Restore Populations of Terns to the Levels of the 1930s: . Arctjc Terns: 8,000 pairs, including 2,300 pairs on Machias Seal Is. Common Terns: 8,000 pairs, including 1,700 pairs on Isles of Shoals Roseate Tern; 275 pairs.

1. Continue current in~ensive management to maintain and increase the numbers of birds nesting at existing successful colonies: at Petit Manan, MatinicliSRoCk, EaStem Egg Rock;

2. Manage vegetation and mineral soil to create suitable nesting sites. a. to provide babi~t that encourages successful reproduction; b. to increase the number of birds nesting;

3. Mitigate Factors (predator~ and competitors) Negatively Affecting Tern Numbers, Distnbution or Reproduction.

4. Discontinue management if the following criteria indicate that ·management is ineffective, not cost-efJ'ective or undesirable. a. productivity is low e~ery year for more than 5 years; \ b. the numbers of nesting pairs shows serious and continuing decline;· c. management actions have negative effects on desireable-species.

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OBJECTIVE -2. Expand the number of islands available.. for terns to nest in the former geographic distribution, based on historical records:

Arctic Terns: 10 colonies; Common Terns: 25 colonies; Roseate Terns: 3 colonies.

(Appendix A: Table 1, Appendix C: Map 1.)

Identify Additional Islands to be Managed Intensively. 1. Insure adequate regional distribution. · . . Recognize that the distributions of the three species differ. Most Common Terns

prefer to nest on inner islands, some quite close to the mainland shore, and histori­cally their numbers were scattered along the entire coast. Arctic Terns were most numerous on outer islands in eastern Maine and their numbers drop off sharply west of Matinicus Rock, where the westward flow of cola water out of_th~_BaY- of Fundy turns offshore. Roseate Terns nest among Common Terns and forage where strong currents carry small fish over shallow sand or gravel bars .

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The three species will be differentially involved in rebuilding historical colonies according to geography.

a. Islands near the mainland will attract primarily Common and Roseate Terns, vis. Trumpet/Ship Island in lower Blue Hill Bay; islands in inner Jericho Bay, in upper Penobscot Bay and the Muscle Ridge:

b. Some islands will attract all three species, vis. Petit Manan, Two Bush, Eastern Egg Rock and North Sugar Loaf .

c. Outer islands will attract primarily Arctic Terns, vis.-Scal Island, Matinicus.

2. Use tlie following criteria to identify specific islands to be intensively managed within the regional guidelines (above):

a. bird§ are nesting currently; b. evidence that predation by mammals or raptors is not a concern, or

that it can be controlled; c. location is consistent with needs for geographic dispersion; d. the existence of a populous (lolony in the region in the

past indicates that adequate food resources are available, though fish prey are notorious for fluctuating in numbers;

e. suitable nesting substrate is present; f. the island's location and topography make it practical to

camp and to maintain a field party from mid-May to the first of August;

g. owners are interested and will allow a field party; h. the present or potential leve_ls of pollution are not

considered prohibitive; i. special measures may be necessary where Roseate Terns nest.

ill. CONDUCT STUDIES TO GUIDE MANAGEMENT PROGRAMS.

1. Investigate the effects of predators and competitors at the major tern nesting sites;

2. Investigate when, where and why tern populations may be vulnerable or are decreasing; . __ When and where possible, identify factors affecting the numbers and distribution of small colonies, and find the causes of failure where breeding fails chronically.

3. Refine survey techniques for censusibg tern populations. Several survey methods should be tested at the colonies with resident field parties in order to refine techniques co·ntinuously: a. estimation of numbers of birds in the air over nesting area; b. mark-recapture index of nests .

\

., ,

•

•

•

13

We need to develop techniques that provide extensive as well as intensive census coverage, because in some years major numbers of failed breeders transfer between islands in late June and early July. We need to test repeatedly the relation between the _m.~!1_1J,ers of birds in the air and the numbers of nests to provide an index for quick assessment on the many small colonies. We need to know how the reliability of these techniques varies with individuals and with the calender. We need to know the importance of taking replicate samples on the same or successive days; we need to know what techniques provide accuracy at the level of significant figures, and yet do not take so much time and group effort that they are impractical at small, dis-persed colonies. ·- ·--- ·-----· ·

We need to establish the average reliability of the several methods of measuring productivity: Some workers, for example, find that the use of exclosures is not suitable on their nesting habitats, some mistrust the use of estimates of the birds in the air as an index of nests present, and some mistrust the use of nest counts, because capture/recapture studies show that they are usually low. We need to identify methods to be used under different circumstances, even though they may provide dif­ferent levels of significance.

We should test the mark-recapture meµiod regularly for its reliability as an index of nests.

4. Investigate techniques or manipulating vegetation so as: a. to attract terns to nest at the site; b. to measure effects of different habitats on breeding success.

Habitat characteristics influence where birds settle, but it is not clear whether habitat quality per se influences breeding success. Some doubt that habitat altera­tion is a practical method of achieving our objectives.

Techniques for manipulating vegetation should be tested, for example: mowing, burning, use of herbicides or rock salt, and soaking with sea water. The management tests-should be designed so that results can be used to improve quality and quantity of nesting habitat on existing and potential nesting islands.

In nearly all colonies of mixed species composition, differences in habitat affect where the species settle. It may be prudent to increase the area of habitats on some islands to encourage one species or another, e.g. large areas of Beach Pea, Angelica and Scotch Lovage may expand the numbers of Roseate Terns.

5. Make General studies or breeding biology These stuaies do not contribute directly to the management program as no

amount of information garnered will allow- us to affect the age and experience of breeding birds, or the food supply available.

a. Estimate survival rates, establish age at first breeding and changes in breeding performance with age; estimate the effects of inter-island movements on calculating survivorship.

It may be practical to color-band terns at some sites to measure lifetime breeding performance, but this is a very labor-intensive study that must be continued over at

- ·····- - --------14

least a decade to achieve results. H such studies are proposed the group should get advice on the validity of the premises, the practicality of the plans, the sample sizes, and the methods of sampling needed to avoid being superficial.

Some have expressed doubt that the current color-banding to estimate site­fidelity and inter-island movements should be continued, unless a coordinated plan including the taking of larger and consistent samples in Maine is agreed upon. All banding must be under permit from the Banding Office of the U.S. Fish & Wildlife Service and the Maine Department of Inland Fisheries and Wildlife.

b. Study feeding ecology and annual differences in feeding rates and weight-gain ---·- ---- - ln temchtcks.

Establish.standardized techniques for examining the occurrence and frequency of prey species in chick diets, feeding rates and weight gain in chicks. Accompany these studies, where possible, with surveys of the distribution of foraging adult terns and stocks of important fish prey (White Hake, Herring, Sand Launce). This information provides indices of current food availability and can be used to track reasons for an­nual differences in nesting success and numbers settling on the colonies.

. .

\ 6. Survey the distribution and abundance Jr Herring and Great Black.:backeO--Gulls.

We need to understand changes in distnl>Ution and numbers in the populations of the large gulls to understand the effects of gulls on the number of islands available for terns and on tew breeding success.

HAP 1

~ ... '

·. ,. ,_, ; . •• i.~

. i: '" , ,. Iii

. hi •:

. I

;:1· ; l '! ~<·:;

·. : ,: .

i : :~ " •

I :. ' J •...• .' \.:;·: ~

.:'. .W 'rt-' I -! ·

. ·-·-~---·---~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Sugar Loaves i

I

..

••

•

i . I

.-::--

Cr:mJ lt.tnan ,,

J.:cnt ls \nnchfos Sc.1 l

This map shows the major bays on the coast of Haine and important tern nesting islands referred to in the text and tables.

• MAP 2

• I .,

Brewer • •

Belfast

pectacle Barred A!J1

Smuttjpoa - ~ ' -

"'11_\J·'· . . \ -· .,r,~ Egg Rock 0• ~ ~ ~.. FRENCHMAN BAY • ,.. ca •

'.' .~-;,".-'; ~\#/" B~UE HILL BAY

• • ~ ~~ . Q ,.,. ,.'2W4/f, •· • o JI'\ ,Ship & Tr . .-. . fJW: .. . •f '~"":'' · , . • o J'\..(I umpet

• PENOBSCOT BA;., • • .. .. . Three Bush l~Cow Pen ~Great Spoon

Little & Large Green

• ;.· , No Mans

.,, Seal ' Wooden Ball

J Little Spoo ERICHO BAY

?""

I I

• •• •

1 Matinicus Rock ! This map· shows islands repeatedly occupied by terns

I in mid-coast and eastern Maine. Terns hav~ repeatedly colonized and then abandoned them after su~fering heavy predation from Herring and Great Black-bac~ed Gulls.

.. ::.

The distance from Eastern Egg Rock to Petit Manan is

shout 140 kilometers . ---1---·; -----_

I

•

•

•

15

APPENDIX As CENSUSES OF TERNS NESTING ON THE MAINE COAST <~old 12) \

TABLE 1. TERNS NESTIN6 IN "AINE IN 1931 <Nuabers are of pairs, Robert P. Allen and Arthur H. Norton, unpubl i shed repo~t to .~he National Association of Audubon Societies>

Stratton Is., <Saco Bay) The Sugar Loaves, <Kennebec Ri ver>

_Garden Is '-~fenobscot Bay) Two Bush Is, <Penobscot Bayl 11etinic Is, <Penobscot Bayl Little Grel?n Is, <Penobscot Bay) Hatinicus Rock, <Penobscot Bay) Bri11stone Is . 1 (Jericho B·ay) Tru11pet I s,- <Blue Hi 11 Bay> Ship Is, !Blue Hill Bay> Petit Hanan Egg Rock, <oH Jonesport) Foster ' s Is. , <Mac~ ias Bay> 1'1achias Seal Island, <Srand ttananl

800 Co••on Terns, a few Roseates. 550 Coa11on 1 150 Roseate Terns 500 Co••on Terns <many young) 100 Co•aon Terns <150 young dead> 150 Arctic and Coamon Terns 300 Coamon Terns 500 Arctic Terns 150 Co1111on Terns 500 Co••on Terns 300 Co1111on Terns 400 Co•aon and Arctic Terns 300 Co••on Terns 600 Co••on, soae Arc~ic Terns

2 1 000 Arctic and soae Oo••on Terns

TABLE 2. CHANGES IN NUMBERS OF TERNS NESTING ON THE GULF OF HAINE COAST

. Couon "te-;::ns- Roseate Arct i c Terns Arctic Terns Terns at Machin Seal

- ·---- 1900-1905 4,000 2,500 100 1930-1935 5,000 I 19 is. 75 l l 5,250 16 3,500

6,000 125 i!5. 1940 s,ooo /25 is. 5,500 2,300 1972 2,600 /18 is. 85 /2 3,000 2, 100 1977 2, 100 /24 is. 80 /3 1, 650 / 9 1t600 1984 2,550 /28 is. 76 /8 1, 720 /18 1, 350 1988 3,100 /14 is. 75 /9 2,oso 17 1I900

The nu11ber s before 1940 are ba sed on es ti ~ates fro• several sources. Co un t s were aade on di fferent sect ior. s of the coas t, and often in different ye ar s . The authors did not eake clear whether t he nu~bers are of b i rds or pa i rs. The nuabers after 1940~~• of pairs; t hose for 1972 and after are ba s ed on surveys of kno~n , potential nest i ng i ~ l a nds .

•

•

16

TABLE 3. INTER-ISLAND HOVEHENTS OF COHHON TERNS OF HID-COAST HAINE <PAIRS>

ISLAND 1972

Petit Hanan 300

No. Penobscot Thru•cap Barred Spectacle

!!i'..

Blue Hill ~ John's · Ruu1e 1 Cove Indian Point

125 2SO

so 25

~Jericho Flye/Sand S•uttynose Southern ~ark Conary Hubble

~ 10

2SO 20

Lo•er "Jericho ~ 6reen Island SO Hason Ledge Gooseberry 70 Great Spoon Litt 1 e Spoon CoNp•n 15 Threebush

loNer Penobscot •H•tinicus Rocle large Green Hetinic Two Bush Brother>

1'1uscon3:.!s ~ Eastern Eqg Ric Killicxstone

Totals :

!!t. s

12S s

75 30

1280

1977

700 .. 300 .

3

25 25

~ =~ ··-20

1984

410

?

7S

20 20

---==---....o

so

BO

1220

60

so 10

180

330 50

1150

198S

7SO

60+

120+

20 30

480

110

1986

750

120+

200

10 10

630

fff

1987

700

130

30

10

__ 20_ 90 70H

270

1320

1988 1989

650 925

BO

150 130

35

12 60

so

40 so 400 100

600 900 so

1450- 2330

• 411 nests of 3 eggs were assu•ed to be Co••on Tern on Matinicus Rock. ·~ In 19B7, several hundred Co••on Terns ca•e into Hetinic Island in

late r ~ 1 and •oved onto Large Green in late June, after the census was taken. ••• In 1986, few terns nested at Eastern- Eqg Rock. No nest count. 7r.is table shows how groups of terns have •oved around, settled

te•por~rily and •oved on in the •id-coast region •

··- ·

APPENDIX B. TABLES OF BIOLOGICAL lNFOR"ATION ON HERRING .GULLS \

17

This infor•ation can be uaed in ••king decisions about ta tern ·•1n1ge--- ­•ent, as ls the reprint of •"•n and "edrlc,• <Island Journal, 1989. Yolu•e six:ll-15). The reprint· offers I brief historical review of the increase of the gull population and how gulls displaced tern• fro• traditional nesting is­land.

Gulls have aoved about a•ong the islands al ong the coasts of th~ Gulf of "aine, even Mhile they were expanding their range to the sou~h. After the decline of .•arket hunting and egging, gull nu•bers decreased on the outer is­l ands where they nested during the first decades of this century. They aoved to nest on inner islands nearer to human sources of food.

"OYEMENTS OF HERRING GULLS A"ON6 BREEDING ISLANDS IN MID- COAST "AINE <Birds, not pairs, unpublished data fro• A.H. Norton and A. O. Gross>

Outer Islands: Great Duck.,-L..u.tl e

Duck •••••••••••• No "•n's Land,

H1tinicus ••••••• "etinic Green •••••• Big Spoon •• ~ •••••

Inner Islandsi Fisheraan's .••• • • • • Western Egg •• ••••• Colt Head, Barred •• Schoodic •••• • • ~ .

. 1920 \

s;ooo

.5 t 000 5,000 1,000

300 50 0 0

1930 1940 -· - . - -- - - ----

4,300

1,000 1,200 1,000

500 500 . so 25

3,300

900 - - - BOO

550

1,500 2,250 1,350 2' 140

This table shows ho" the nuabers of Herring Gulls increased for sev~ral decades on eajor offshore nesting islands. Then, about aid-century, their nuabers began to decrease steadily.

. ... ·······----

••

18

TABLE OF CHANGES IN NUMBERS OF GULLS • TERNS NESTING ON OUTER ISLANDS Fro• Drury, N.H. Gull Increase, ~erns, and Gull Control in New England, USA, (in press> sub•itted to Biological Conservati"1>ftn-.~~~~

l'fUSKEGET ISLAND KENT ISLAND HERR I NG -GULL

~ ISLES OF SHOALS HERRING GR'T .BLK-BK TERNS LAUGHING 6. HERRING GULL

1880s 1890s 1900s 1910s 1921 1920s 1931 1930s 1937 1940 1941 1945 1947 1949 1951 1954 1961 1963 1965 1967 1972 1973 1975 1979 1990 1999

20,000 16,000

* * * * * .. * ..

( 1) * (2) ..

*

500

2,700

3,750 25,000- <3>-•---30,000 (4) 4

17 '000 (5) •

• * io,ooo __ tb>- •-

7 ,500 (6) f

B,350 <7> • 8~000 (6) f

4, 000 <Bl t I

4,560 (9) •

5,000 (10) 4

? ..

4,900

S,900

7,000

4,650

4,000 2,500

0

3

16 ~ so

120

725

1, 1 so

1,300

2,oso 2,500

* f

* * * • f

f

f

f

- · . * f

• • * * • t t .. f

f

• -----~-

•

4,000

9,ooo 13,000

20,000

eso

0

- 0

0

0

45 650

i,ooo

1,500

20,000

5,000

700

400

0

0 0

150

200 400

13,000

20,000 16 ,ooo 13,000 10,000

B,500

0 ·····- 2«>_0 ___ 3,500

o- - 0

~ 0 0 - 0

... 900 700 100

- ·

Data for Kent Island show the decline .at an island of •ajor i~port•nce early in the 20th century. (1) Pettingill 1939; (2) Crystal 1941; (3) Cauron 1945; (4) Gross 1947; <Sl Pialott 1952; (6) Drury, air est.; (7} Ainley 1967J (81 Drury, sudace est.; (9) Lock 1983; (10) Cannell and Maddox 1983.

Data for Isles of Shoals show the increase of Herring Gulls and their decline after "Earth Day,• ~hile Great Black-backed Gulls have been steadily increasing. Palmer <1949>, Drury (1973/74> and Borror <1990, pers. co•• . >.

Data for Muskeget Island <see Drury 1973/19741 -~fio~ the replace•ent of terns by Laughing Gulls, then Laughing Gulls by the larger Herring Gulls. In the late 1980s the island was sparcely occupied, pri•arily by Great Black­backed Gulls, as the Herring Gulls had •oved to "onoaoy Island near the aain­land •

, . •• ..

'

•

. ----··------ --

19

An ieportant feature of the population biology of Herring Gulls is that they do not reproduc~ equally well on all nesting islands. In fact, the birds nesting on aost of the outer islands, where gulls are harassing terns, produce·-­very few young, and their nuabers appear to be aaintained by iaaigration of young gulls er.eluded froe breeding at the larger nesting islands. Thus 9 these islands play little part in aaintaining the coast "s gull population, which is such an important part of the Gulf of Haine.

BREEDING SUCCESS ON 6ULLERIES OF DIFFERENT SIZES BETWEEN LONG ISLAND AND GRAND MANAN

Islands with Islands with Islands with over 400 pairs 40-400 pairs less than 40 pairs

number I nu ab er l nucnber x

Study Colonies ••. . 1 t 25% 34 75% ..... .. Chicks fledged . . . . 26,871 B!\l S,285 16X ....... Total colonies 76 321

\ 311 551 31 131 .... .

Tohl Nests -·~,,...,.-104, 700 BU 23,600 181 ... 840 0.61

Ave. Production <chicks per nest extrapolated from study islands) 1.15 0.95 0.70 .... .

Total Chicks fledged - (nuaber of nests x average production.) 120,000 841 . .. 22,000 151 •.• 600 ••• 0.4%

<Fro• Drury, W.H., and I .C .T. Nisbet, 1972 . The iaportance of "oveaents in the biology of Herring Gulls in New England. in Population Ecology of Higratory Birds: a Sy•posiua. U.S. Dept. of Interior Wildlife Research Report 2. 27Bp. l

I .· :·· · ~ . . · ·-'

·-- ,. . '.~·· • 1 •

fdAN &MEDRIC Historical Biology of Gulls & Terns

T 11t 1·111·11-\11<>:-:,11ra11.,..·al11nl,on

1111· t·11.1''' 111 tht• :S11rth A1lan1ic­h,I\ 1· c h :111gc-cl rc·markahh 11\'t·r 1 ht· 1 ..... 1 :\Oii H·.11,_ I lll'rt" 1~ no t"\'i­

cl1·1u 1· 1h:11 thi' i11,1ahilit\ '' 111·,,· or 1h:11 C"h:111g ..... 11c· 111l1r1c 1111' -h:icl,- h11111c 0 \1°rllw­

h-" \\I" hlllll.lll\ h.1n· I 1111\Hkrt·cl -.!IOlt'

d1,111~1 ·, l<I h.1\1 hcTll '"·

I )111111g 1111· l.111 · 1><111 and all .,1 tlll' l!hh

ct'11111". rlw .'.c ·" l-.11g l.1111l-~l .11 i111111•, rc·gi1111 wa.' ,1, 111111h :1c1·1111·1 11l 1·r1111111nic clc·\c•lnJ> llll"llf ,)\~,1le • 11t , f\Cl\11111, :\,1111111 kt0 l. l'hil,11Jd­pf11,1, 111 ( :ti.11 ln11111. \hip' l1111h .111!1 ,,1ikcl ..,, t re·'" lr<1111 \l.11111· and 1he· ~f.iri1i111c·'

plwrl 1111· '1 '. I i.1111'\ 111 \\111 lrl e lllllllll'rc'e'. :'\11rrli1-.1''' · ·111• 1 .. uf 11111·111.1111111.1l 1r.11l1·"1·rc· (11,11111pnl11.111 \\Iulo 11111< It 111 1111" fl''' 111 <~111.1d.1 .111111111 I \ h.1111111h 11·1 e·111h 1..-,·11 'l<'ll l<t l Ji, I" ·''-1::1 111 11111;!1.1111' I \1tl1 ·111,. 111

""' I .111 lu " .... Ill rlw '·"I 111.11 If 111111. 1111111 1'1~7 !11f t lu , ,,,., •• t \l.111u &• • rt ·;.:.1111 tlu· p111111 l.1111111 I•'' 11 h .111111 rite l)(Ktf,

I 11 I he· I \II 11 • , 111 :1" . 1111· e 11,1,1 .11ul 1,l,11111\ 11( Ille" ,,." l-11::t.111d·\l.1n111111·, \\l"rt' 11("(11·

pie e I I" ,,..,'I''' , , • "', fc·d 11111 • 1 he· 11·11tc·r, nl c1111 11 : :1 11 • ·. "11111 1i-l1<·111u·11 .111d llw1r l.11ni-

h1·, , .1,..._.i ••1ll .• '"'"'''·""'" ll\111i.:1111 m:11n of lhe· 111 .. rc· rc·11111..- 1,l.11111, and u1111·r 111.L'L'. The·' n111H·cl 1lll' 1r l.11111ht·' lu 1lw 1,l,11111, in tlw 'Pl 111g 1u Ix 111·.11 tht· lhl1111g grounib.

lxt.111~· 1lw ~.111t11i.: ''""P' I ru111 "ht ch 1hcy d1cl 1h1·ir da, . r.,11111Jt. ,,e·rt· 111 ce111.,..·n-;Jti\e dt•,ig11 :.111cl ,1 .. ,, .. ~

F.11niht'!I i11 1h1· c-~1mp' and ~m.111 M·lllt' m t'llu u .... ·cl" h.11n 1·1 111• "I "~t,a\:1il.1hll·. Tht·' all" ~·.1hird l·g,.:' .. 111el -.1ltt·cl c-hicl' lnr hait in tht· 1 ncl li~hl·n . ·1 h1· Mll:Jll hirtb., li l..1· l..t·.ich 's p<·111·1, .111cl 1l11•w :h.11 11n11·d 111 111("1. 1 rn· in·, lil..1· p11lli11' .111 tl hl.11 I.. ,.:11ille·111111,. \\l'rt'

V\1 I L L I A M H. D R U R Y

Sl'fLshorf' nnd sm birds gn to~lhf'T" in our psyrhl'. Whm WI' see the onl'

111,. l'XjJPrt ti" other, must pnrticuu1rlJ · J:rUlls n_nd Inns, th,. designated

l{fllf'kf'1'f>n3 nnd rrsidrnt rnlmainrn

of i'ilnnd f'Xpnimrf'. Thf'Sf' nrl' fhl' jmJpU. 'J birds; llu otlurs ar,. in 11i,. am of birdwatchn-s. Al lhal, ii is rhillin~ lo think lhnl herring f:rUlls

wrrP nmr~\' 111ifml oul mrZ-r in thi.\ rm/111), mui lhnl /n71s nrf' md1111g""' in uur m1m timP.

Omitl/fJ/ngisl lo !hi' is/nnd.s, Prof. \\ llllfl 111 I Jn tr;; wriff'\ ef n 11'T')·body ·, 11•/iitr hirds 011 !hi' ran.sf of .\lni11I'.

l..illnl II\ p1·1 du,.:' .11111 C:Jh. or 1r;1p1x·d in ll\·111111: 11e·1, \l"t oH·r j uml>kd l>1111lckr... at 111gh1. B' 1h1· nuclc!k or the 19th ccntu~. t·1gh1 ~pt·n1·, ul <t:ahirds. including gr('"at Jttl..' .111<1 l~hr.idur ducl...s. had l>c.·l·n l ilkd o0 .1long thc ~\'\\' l::ngland CO:l.SI. and tht· n111111>c.·r~ or 1h1· remainder were seriously rt·cluc-ed.

Then a nC\\· 1hrea1 emerged-fashion de­mamlcd 1ha1 lac!ics should wear fcoithers on thl·ir ha as. ThiHfrmand produced two great c:impai~1<or shoot.inggulls. tems.and t:gTets for 1 heir kathers in I Ri6 and 1896. Arthur H. :Sunon. i.Ti1ing in the early 1930·s from hh em-n l·xpcrit-nce . told of the -fe:uher campaign!\- and listed 15 islands in ~faine·s

~lu"'ongus and Penobscot bays from " ·hich 1cm~ wen· ex11·nnm:11ed in 1hc late 1880's, and Imm C;l'I<!• Bay i,Jands in IAA9 to Jlt90.

:-;o ct.:'u.c; OR SHAGS

l::dward Sturtcvanl, C0·3uthor or Birdc n Rhnb Island and a onc--timc market gianm·; told me thaf tht'rt· ,,·,·re thrt't' yt·ar.\ d11ri11) 1lw late IH70's wht·n ht· did not ~·<.·a 'inglc sc.·:i gull. At the tum or tht· n ·ntun . ~11rt111

;uul l>utcht·r r<'poru·d that tht·ir "'"'"'' 11 the · COil.\t of ~!aim· ,1111wt'd 1111 nntin~ ~rt·a1

black-backt'd gull~ or douhlt'<n'M<'d cormo r.mts, and tht· prt:st·nn· of only fin· fl-malt eidl•n. and ti.·u pair:. oJ ,\tl:in1ic puffin, (1111 ~l :uinicm Rud..) .

.\1-tlw ..:mw tinu·. \\'<.·nddl Tu~ll'l.01HI r<'· pum·d ahout :»o lt-111al1· dch·r... and ;\o pul· fi11, aro1111<1 ( ;r;uul ~lan:in . I krrin~ ~11lh

ne·,rc-d 1111 a ft-w ul 1lw 1111tl"r i,l.11111' 111 c·.l\t· e·m ~taint·. a ncl till' :S.11ional A'">eia1t1111 of \11el11hrn1 Sc>ei1·1in hirt·d w;irclt·n' In pr11tl'l 1

:111·111 from tht· 1lt-pn·cl.1111m' or lilt' p l11111c-11111111·r,.

I 1·r11' 1,1·n· n111li11<.·cl 111 11t·,1111g 1111 Blull hl.111cl -.i1111h orl111rtl.111d, 1w11 b l.111cl ' Ill llllll"r \h1 \C11ngm Ba~. thrn· n·m1111· j,Jand' in 1h1· .1ppr11ach1·s 111 Penoh'C"ul an cl J1·nc-h11 h:I\ '· ,m,111 islands in uppc:r P1·n11h'<"lll 8.1'. :.11111 "11 du· 11111cr island' in 1·:"11·n1m11'1 ~l:11n1·.

Tlw exceptions ~·t·r{' the island) on ~hi ch lighthou5e.-s were mainuined. For SC"\C'r.:11 c ritic:il decades. ligh1ho o<.e opc·r.uors and 1hdr families from ~lachias Seal . l..ibb~ ls-1..tnd, Petit ~fan.an, Great Duck, Grc-;it Spoon. aud ~latinicus Rock kepi orTbolh lh<' preda­l•>f) rearher-huntenand thC' prC'd:lton·PJllS. l 'nfonunately their family pcu. dogs. and cal' dt."\<blatcd the nesting populations or somcsmallscabirds.lilu: lr.u:h'sstonn petrel and black guillemou.

All St"ahirds ha,·c incrl'3S<'9 sincc- th<'n, .. ncl rive of the ~pccic~ that had l>c.·cn eMir-

' ·'""'" I:\

------- - ---:-. -.-.. ····--... .. ............ ... .... ...... . ---~11rmorJ111.s., l(rc:u curmor;im~. l(rt'Olt black­

h;ackc.-ct l{Ulls. r.v.urhills. ;and common mur­re~. Mu!ll species h;n-r incrc-;L~d sll':idily'. anct so rapidly 3.\ 111 suggest colonization from rdugc:~ in thl· ~laritime Prminces. So. it ~"t'm\ prohahlC' that rC'chmdan~· or geo­graphic;ally rc:motc gnctuaries pla\·ed an impo~nt pan in tht"le spccies

0

l"1c;apc from extinction. This m<>'·cment of scabircb among several g~raphic area.\ has, pre­sumably. allowed thc:m to persist in habit.al\ th:u ha\T repcatedl~· changed in space and time in the pa.\t.

GL'LLS !~CR.EASE A!'() EXPA..'\D :-;onon n·porn·dlliac h1· I~ 11 hl·rring gull\ had occupil·<l small i.\lanch l"l.'I of ~orth Haven in inner Pcnoh\Cot Bayancl th(' Spoon hlanch in jl·richo l\a~-. forcing the tnm 111 !>e:l'I• othl·r plan·s to Ol'\I. Ry I !I:! I ht·rring gull' had c11l11ni1ccl hlanc" Iii) mik'I 111 thl· '-('\ t uf their prc:\i ou\ limit ancl Tuwn\Cnc! rl'p<>rll"Ci about 20.000 gull:i nc:sting in the: Grand ~fanan archipelago. ~kam1·hik. the.- numben of gulls nl'.\ting

on thl' outt·r i'lanch in ~t.1inl' ckcn:a'l<·cl 3.\ ..C<t\-:mging hirds muwct clo!l<'r 111 the: main· land ancl to islancb m·ar fi sh planL\. Many summer fish camps "·ere ;ahandonC'd to the gulls and flocks of maroonc:d sheep.

--RAP~ID R£COVERY OF TERSS :"onon rC'p<>rted that tt•rn\ had n·occupicd mam· islands h., 1903, with fi,500 common and Arctic tern~ nesting on 18 islancls. Terns ·ncrn..scd rapidly and n-achrd JX'ilk num­

rs in"lhe late 193()',. Thi' inrr<'a.\«" may a\·e been a rc:Co\'c:ry of prl"lillUS numhcrs,

or it may h:wt" hn-n a phrnom<'non of a 'f>C'cial pc'riod "ith sped.ii a<h-.1111"'gc:s for Jc:rns ~ K""ining suddt"n access 10 a large number of islands traditionally occupiC'd by gull\.

By the early 1930'sthctcrnsin Main<' were cluing '- t·ll. anri fort11na11 ·h· thdr numbers '-l'rt: CC'O\U\Cd. The cli,trihution:o; or the three: 'P'-"cin d ifTl·r. ~lm1 common terns were found on inn<"r.hl.inds, somC' quite clo'C' to the main shore' . and their numhcrs Wl·rt· C' l·nh· spread :ilnnl{ the cna.\I . Arrtir 1t·rn11 -.·rn· mc"t n11m1·r1111 ' 1111 0111c:r illlancl:o; in l".L~tl·ri1\fai1w ancl1hl·1 r n umher\clrup111T ,h,1rph '-t•\t of ~l;11m1c11 ' Rock. whl·rc: the Wl'~l'A<irr! IJow of cold .... ;i1rr tJ UI of the (l:l\' of Fund\ 111rn:o; ofT,hnrt'.

CAPE CO O SHIFTS Th(' sh;I• •!•f~rm1p\11ftt·m, ... ,.,-.i,· from tr.icli­iion:il -p· •pulous - i.J:inch h.u been l"lidcnt many tin '°"' in the I&~ drc .Kies as gulls ha\"C occupiec: , one after another, the major tradition .1 nesting iJ:.and• Jlong the coast of f'\cw Eng :ind. Mo11t recC'111lnJhr tC'mll n<'sl· ing at Pi:tit Manan . cas1 uf '1ount Desert lsl:md,11t- >Wed ·malai~-ahout 1978.a.,~llll

Jr.In tt• •rOll(Wrt th<' i~l.11ul .mcl 10 inrrC'3.'<' cla11o11 pn·~'un· 011tlw1c·ms.

111 I 9'i> :ipµrmtim:1u·h·: . Hiii pair.ioftl·m~ h:1cl tl<"'tr Inn rl·tit M.111 .111 "'hile about l!'lO p;1ir.1 o f I! lb nc~tecl 1111 11• 1..:'i boring CrC'en

_ bland. Jt :inli111< 1u.Jnt·n1• Ii.itch. AflC'rth<' lit( hi hul I"' t • U l•t•I i1 ~· ·· • • •• • · ••••••u ... • 11 ... t : ••

• ., • - · ,, "" .u 1 l'!\lt1t·nt 111<·0 the: re tur ~·\·l·r;,al

years. and lhl·n the i11land hccame \""ac;mt. (!ull numhc:rs increased to aoout 350 pain on Grt·cn bl.inti and 10 pairs had ~ult"<! on Petit ~fanan in 19i7. according to \.;irl Korschgcn. By 19i8 terns and laughing gulls hl-g;.in to <lc:crl·ax. and by 19t!'.l the te)"lls had ahancinncd the island.

In 1984 sc1mC' of m~· studc:nu looked into what was happening to the displaced tl·rns. some of ~·hich settled on Ffat Island and :"-lash Island about 10 mil~ to the eait of Petit Manan anct nth<'n on Egg Rock in Frenchm;,an &~.about I:! milC's to thC' west. Those campccl on Flat and :'\:L'h i\land' n.-pon('cl that gulls, after 11ix da1·\ of fog which clt·nil·cl thl·m arCC":\.\ 11> tht·ir usual food acquiH·d follo,.,ing loh,tcr hoaL\. be· l(all to hunt in thl· tern nesting arc:a and 111

dean 1111t .ill the \·1111ng rhick.\. Th e '11uk11t' at F.gg Rock n·pc•nl·cl gulb pc11111ri11~ 1111

incuhatilll( adult laughing 1(1111~ ;11111 tl'"" fro m the air. and c:ating thc:m ali\l'.

Al this same time. StC"·e Kress of the: ~a­

tional Audubon Society began to u~ dl·co~' and tape recording' of ll'rn ralls to a11r.1rt tc:m\ 10 n·turn to ~:a.,tl·rn E~g Ruck in ~'"'· COnJ..'US Bay. ahout x;, miks lU thl· "'"'" Hc:rring gulls had displaced terns from 1ha1 island by J920. according-10 Anhur :"ono::; In earlyjuly in 1980, well after the usual time: to scnlc 10 brttd, ~mt' RO pain of common terns sculed in. S1e1·e re:uonc:d that thellC first colonisL\ were fail<"d hrC'cdt•rJI from otht·r tC'rnc:ries. In 19HI anothc:r XO pair.i arri\-cd in late June and earl~·July, and by late Augwl 198U24 pairs " ·ere nesting: 400 pairs of common te'rns an<l 20 pairs of Ar« tit: terns. A5 StC\T said:

"Since ~lainc tt>rn n>lonic:\ ha\·c bcc.-n de­clin in)( for ;,approximatr1'·40)Tan. and there has t>cen considerable inter<olony mo\-c• ment during this period, there is no way to be certain of the specific sourcc(s) for the

l::gg Ruck wrn population. l luwc.-vl·r, tht• WXO brc;ikup of the larKe tern colony at Pl·tit M:man bland, looted approximately 14."l KM ca..\t of [gg Rock. is a likely source.

1'hc 1rmpor.1ry· incre:i.'IC in numlx·rs of terns nesting on mam· islands made it diffi­cult lu comince the people on those islands that the tc:m population "'"-' in trouble. From their n:irrnw \iMo-, the tc.-rns were in . good shape. This point emphasizes the nc.-ed to keep Jrack....of terns o\·er a long stretch of coast, :md tu rc:-.. li.ce that subpopu· l:itions arc: stronl(ly innuc:nced by immigra· ti on and emigr.ition ....

HOW Gl ' I.IS C:Ol.0~17.F. !'F.W ISl.A.'\DS Thr incrc:L"I' in thl· E.ut C.:o:L\I herring gull pc1p11lat io11 rt•nt'Ctt·cl r.ipici and continuing i'lancl colu11i1ing. Thi' meant that many '"""lo: hin" '("llh-11 1111 : 111 i\l:111ci at some cfi,1.111n· "Imm h11111t-. - L' '"ally among \t'a· hirch. '"""J.: lurd' .1n· ' 1ru11gk ;111r.iCtl'ri to l'St;1hlishl-cl citil·\ ancl ;irl' hcsit.anl to nest alonl'. So young bircl\. m ·wl\' recruited to the hrccding pc1pula1iun. are auracted 10 fulh 11ccupil·d "1.md,, l'\'l'n though m<in~·

11tht·r hi.mets may be t·mpt~-. This efTc:ct mually i11hihi1.' the: );rc>Wth of scahird num­hcl'"\.

Thcgro"-ih of the herring gull population and south"'-ard extension or their breeding range continuc:d during the 1950's, to \.on· n<"cticut, f'\ew'Je~y. :md Maryland. The lirst herring gull colonists reached !'lonh C<trolina about 1960. and the colonies south of~t"'ft· York continued lo grow in the I 970's and 1980's.

AJ1hn11gh thC" numt>cr or herring gulls nnting in Maine did not inereascagain after the control prclj(r.un of the 1940·~. gulls continued to shift around among the is­lands.

Once an area is colonized only a relatively small number of gulleries · is needed to

Gulf of Maine Tern Working Group The poet Kathleen IUine refers to terns as ·1he signature.- of the sea.· Few would dis­agree that the sight of a pair of terns locked in a couruhip night over an outer island is one of the rare treasures on the Maine coast. But what will it taltc to guan.n~ the long­tcnn preservation of thnc fragile popula­tions? This question i.s at the core of the threc-ycar<>ld Culfof~ne Tern Work.ing Croup.

The working group lus approximately 20 mcmbc:nwith rcprc-scntativnfrom the U.S. fo.h aJfOWildrtfe Scnicc. the- Canadian Wildlife Service, the National Audubon Society, The Maine Audubon Society, the Maine Dcpanmenloflnbnd Ft.Sh and Wild­life, and the bbnd hulitut.e. Memben gather In late summer to aharc census chta collected at all the temerlcs in the Gulf of Maine. The 1988 meeting waa held In lat.c August at the National Audubon Society Camp on HO!{ Island In Bremen, Maine. ·

When the dust settled members 'ttportcd terns nesting on only 19 of the 3.000.plw islands in the Gulf of Maine. Some 6,853 pairs of terns were found nesting on these islands. The br:caltdown by species was as follows. 2,955 pairs of common terns. 3,824 pairs of Arctic terns. and 74 pairs of the re­cently endangered roseate tern. On 9CVCral islands the productivity ·or the terns was measured and averaged approxi.matdy one , fledgling per nesting pair. The Cate of the . Gulf of Maine terns ii inti.nutcly dcd to the ·'E ·. fate of the 19 islands that suppon thcin. In -... :·:. 1977, 25 islands supported 5,.521. pain of .. ':-~ terns. So in the Wt decade -we haw: ac:tualty : \ .; ~ned 1,500 pain but Josi iiJc ·nCldng· i..~~ land.a. At one time or another c:iYer the Wt"­-400 years 37 different Gulf of M2lne Islands an: known to have supported a maximum of 11.000 pairs of tcrnL The big plcwn: b that . · ~ It ap~ the region b loosing·~ tc.m•~~~­and u:m nesting islands. What actiona lhouJd -. -

~,-pruchu·c• tlu· roUlll( hi1 cl:i th:ll kl•t•p the p11pul.11 i1111 K""''" RqJnHl11cuu11 u11 other hl:tn<h b not importanc.

Thi' 1111·a11' 1wu thini.t': lif'\t, that l'limi-11.11111i.: i.:1111' lr11111a1111111h1·r or 1111tt·r islaml:i "hi·n- tc·rns might nl·~I will have 1111dfrrt1111 ·rl·clut ing the· gull population.• Scc1111ct, that 1111r conn·rn for terns must IM: focused

011 tho"W: i~lancls wh1·rc parent.s produce cnouj(h >«>11111{ to export. These colunie~will he ahk to mainuain the population, but kccpinj( tems nesting on islands where par­cnu fail. provides a population sink. To 111.1n:tgr a trrn pop11l:ttion we• necci to m:tke )llr<' "hrn we· attrnct hircts It> a noting isl a net 1h.11 they hrccd succes.srully.

n.tc:IJ-:Rl~G TERS WINCSAlTRACTCUU..S , ~·\l'r.11 hiol11g1slS in Scandinavia have po11111·d out the impon~nce of groups of i.:1111, alrt'aciy in rcsictcnce as a · signal" lo hml' pn>)fJl'Cling for nesting territories. The ,..,,,·nt.' or the 1960's suggest that nesting ht·rring gulls serve this "ethological signal runrtion. • noi o nly for o ther herring gulls. 11111 .11 ... • f, 1rn1l11ni1ingcl1111hlc·<rc:-11·ct cunno-1 .111h. t·ickr~. and great black-backed gulls.

L' nlurtunatcl}'. nesting terns pro\ide ·)1gnal \'alue· for thif ethological function and altract herring gulls. We saw gulls ·a1-1r.ic1ed to tems at Large Green Island, Wuodt'n Ball. and Petit Manan, and at Tern hlanct and Monomoy Island on Cape Cod.

(;L't.1.S AS A!': ·omClAI.' PROBLEM Ouri11g the Cr~! Depression in ·downcast• ~laine. farmers used sea herring and ale­""'''' 10 ft·nili11· their fields. The rcacfy '"f>f>h of fi,h . ~pread out as ir for them, .111r.ined J;Ulls lo lhe uplands and to the an-11m-.:ince o f fanncrs. The good times had ,ucfdl·nly comc for the gulls. But beginning in l!J:H thl· Biological Survey of the t;.S. lkpanmcn t of Agriculture (now the Fish &

l>c• t.1lr11 lO insuH· the long-tenn \iability or 1c ''"~ At the H·n least the islands that • 11rT1·111h )Uppon t.hc majorityofternsshould hc guarantct'd protection. And t.he best way to do this is to pcxt tern wardens. Of the 19 <'UITcntly activc 1cm islands. 10 of them "llppon 90% ol inc terns found in t.he re­gion. From cast •() west these islands are; ~bchlas Seal, Pt :.i t M2nan, Indian Point. Eastern Cowpcn , , ~arinicw Rock, Large ween, Ea.stem Lgg Rock. Str.atton Island. Pond lsbnd, anJ \\'~t Goose Rods. The ownenh i p pa u.e:-:1 of~ islands i.s varied. r.anging from Cai~~ed. U.S. owned, st:at.e owned. and :tj_vatc)y owned. Qorly we need to look lc:i~ and hard to sec ift.hesc isbnc:U afford lon~cnn protection. One eolution would b- '" incorporate these i> bnw into a dis;;· · · -;d Tern SanctU21')' Sy. ltm where protc< uon and monitoring by ltSK!cnt tern waro("nscould be a continuing and coordin:11~• -f".,n .

Wiltllill-St·rvicc) ancl the Maine l>cpitrH11e111 ufSca anti Shore Fi.'lhcric:i bcKall a program to n·<lucc th<' l(rnwing gull population.

l\v l!J'10 &he M;iinc nt'!lting i.'lland., Wl' rt' uncln IH'avy pre.'l."ll't' hy t'~K~prJyinl( rrc'W!I l><"nt 1111 haltini; gull hrt·t'cling. C:lt>!ll' 111 350,00CJ l'JOt.'I were .'lprJy1·d in l!J40-19'14. 111 194!'1 it w;L~ cleoir 1h:.1t the numbers of bird:1 nesting in Maine were dt:crea,ing, hut thl· numhc:rs nc~tinK in Mu'4!chuscus were in· crca.'ling rapidly.

The population of gulls nesting in Maine · grewonlyslowlyduring the I 950's, and some . ran argu<' that the- program wa.'I working. The- population in ~:.1 ine hautayc:d ·conM:r­vativc" since the program was ended, and it seems likely that the effect is the same as that of the gulls moving from outer islands to the inner islands in the 1930's and 1940's.

LETHAL COl'ITROL Between 1967 and 1973, we worked with Biological Scrvicesagentsjohn Peterson and Frank Gramlich of the Fish and \\'ildlife Scnice to conduct control experiments at i~lancb wht·rc gull' were cncruachini; un terns.

We tried Alpha...(;hloraJosc at Tern Island in Chatham on Cape Cod, where we were

1 allempting 10 restore a formerly import.ant Lem nesting site t.ha1 had been taken over by gulls in the early J 960' s. The poison worked when used massively for a shon period, as it • had in Europe.

Thi.'1 exerciM: I.Al ugh 1 u.nhat as we removed the nesting birds a number of gulls. espe­cially immatures, replaced them. Killing gull~on Tern blancf wa.' not hcingsuccessful because we had to "'bleed down· the surplus of young gulls interested in, but excluded from, breeding.

SUCCESSFUL lllITERVE.'l'TION IS MAISF­Ourexpericnce at Matinicus Rock in the late 1960' s illustrated h<>"· it could come together, even though many doctrinaire protection­ists were still opposed. Carl and Francis Buchheister (former President of the Sa­tional Audubon Society) spent \-acations in a camp on Matinicus Rock m lhC' 1960"s. \\'i1h a long-1cnn agenda m mind. J suggestC'd to Carl that hc w:uch ror indications that the ht'rring gulls new I~ sculed on the Roel were disturbing tern ncsu...

I think theywcrC' alrC'ad~·awarc. because at the end orthc first summC'r. C:irl and Francis both commented t.ha1 they had seen gulls Laking tern chick.sand had found 5c:'·e ral or the bands t.h~· had put on 1cms in gull nests on the nonh end oft.he" Rock. Carl endorsed a prograp to rcmO\"C the new gulh:olonisl.S.. and Frank Gramlich or lhc Di\ision of Bi~ logical Services tolled them to bread, poi­soncd with 1339, thrown out behind a ~l circling t.he island. The terns enjoyed an. other ten years of successful reproduction.

StC""C Krns embarked on a similar pr~ grJm in 1974 a1 Ea.stem Egg Rock. and r<'poncd thC' events:

• ... Well-established gull populations art• not likt·ly to decline unles.s the-re is rq;eHl'l l .11:<1 ' r:-•, .. ,. ~r1· ~·~in~ f:1 ilur1-. i111·n·a"·cl mnr1;1l 11v .ind C'migr.ttion for .11

l1·a~1 1hrn• 11m11111t'l'11. Ew11 ah1·r thi11 pl·riucl ofcontrol, cu111i11m·rl tkMruc1ion of dutches late in lnruha1io11 will IK' tll'C'('S.'l:lry to k1·c-p 1(1111 pop11la1i1111~ Imm 1111i<'kly rcho1111cli111(. •

1•1111.osor1 lll:AI. QUt'.STIONS Some people han· n·ro1111111·nded th;u the emirl' l(Ull J'l1p11t.11i1111 ura rqtional .IK.'l(mt:nt Ix· reduced. Th<' rt':llity of the reproductive potential of gull11 ;met the lluidity of &he populalionssugg(.'Sl that thisisa much larger unden:aking than its pmponents rt"al ize. It is a prajcct that would require the coopera­tion ol operator!\ all m•rr mn.,t of the c-a.'t CllJ.'t hcrrin~ gull rani.:c. ;ind it is unlikely that such cooperation would he given. lfthc numbers or gull~ were seriously reduced, they would probahly first become scarce in remote places. hc:cawc mo~ gulh are at· tracted to food around towns and ci ties. h is more reasonablt" and erTccti\'e to remove the auractions where gulls gather and hc:come pests..

The problem ofJ.rullsisimportanl in places where fnrcesstronglyauract-a relati\'elysmall 1111111her of gulb. That i.\ "'hat we are dealing wilh at vulnerable tern colonies. But reduc­ing the problems to a small number of areas and a minimum number of gulls is not good enough for some commiued ide11ists. ~any people with whom I must debate

killing gulls prefer to deny tha t any need exists. Some argue against killing o n hu­manitarian grounds. I agree; k.illing is not a prcuy or enjoyable activity. But gulls eating living tern chicks is not a preny sight. nor is the sight of a herring gull pecking at the bleeding head or a li\ing laughing gull that was just recently incubating it.s eggs.

J think that the philosophical question of killing one species to fa\'Oranothcr"-as made and accepted ~·~me early agriculturalists who pulled up plants that inhibited the growth of their crop~ - they weeded the garden. A biologist can argue that it is

· pn·cious and !ie:lf~ning to make a phi lo· sophical scpar.uioa of plants from animals, or ·1o"·cr animals· rmm \·cnebrates. or us. Why should fish he placed ·he)'Ond the pale:­When we find nJlncrahlc speciC'S that " e thinl arc important. and "-ant to encourage· them, we may ha,·e to seed the garden.

As to the philosophical i~ue of nature·, order and "pla~ing God.· we now k.now that la~z-fairc ecol<>ID·· like lais.scz-faire eco­nomics. dunn'l lcad tu balanced S\":ltcms. 11

leads to monopolies. Some species "ill i.alc ovcr and .uscrt an order fa,'Orable to them. whether whitc spruce or starfish or herring gulls. L'nlcu we bclil"\·e that there is a natu­ral order C'Sl3hlishcd at the creation, we should acltnowledgl' that when "'~ won't pla~· God. someone else will.

WiUja,. H. Drvry, Ph.D., is a Pro/ns.ur of Evolu­tionary Biolbr:J and C,,,,U,,, a I IM C,olJ,,gr of tJv Atlantic. F1V111 lii1 fiM bau on Crrm 's Island off \.i11nlhavrn, Drury luu brm JIUdJing IN f'CfllogJ of Mnin' V<1bi1t/J for 1111" J hradrs.

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APPENDIX C. "AINE ISLANDS HISTORICALLY RECORDED AS TERN NESTING SITES - .. ----------------

The following list includes those islands which Arthur Norton identified as supporting. nu•bers of nesting terns between 1880 and 1920. It is the best infor~ation available on where terns should do well. The list also includes those islands to which terns •oved when they were driven off the preferred nesting sites. We should probably not attract terns to the secondary islands, as they •ay not have access to food or they 5ay be vulnerable to predation. Terns nesting at such places •ay act as a population sink.

Probably the earliest and most iaportant list of traditional nest­ing sites is Arthur Norton's hand-written aanuscript in the archives of the University of Maine at Orono, discovered by Ralph Palaer.

•in 1885 terns occupied numerous, long-established, often populous colonies on aany, the following islands. Fro~ west to east, Bluff Island, Casco Bay. The Outer, Inner Green Islands and Junk of Pork, Western Brown Cow, Western _Hark Islands, White ~ull, and E\stern Brown_Cow-1.JL..C.asco Bay. In this bay ~ven the Upper Green Islands, were occupied for a nu•ber of years\

East of Saall Point, the Heron Islands, and Egg Rock, off Popha• Beach, Black Rock in Sheepscot Bay, Da•ariscov~ Island, the adjacent Pumpkin Knob, Thru•cap, were regular breeding places.

In l'luscongus_ Bay Sharie Rock, Eastern and ' We_s_tern Egg Rocks, and aaong the Georges Islands, Shag Ledges and the Sisters, af­forded breeding places for colonies of from one to several hundred of pairs.

Penobscot Bay Mas the hoae of nuaerous colonies, aany--o·f --­thea very populous. These included "etinic Green Island, Big and Little Green Island, Wooden Ball and Matinicus Seal Island, Matinicus Rock . Big ho Bush, the Claa Ledges, Litt-le-Hurricane, Garden Island, Harble Head and Fisheraan's Islands, Rbbinson's Rock and Mouse Island several seall rocks· or islets- north a11d northeast of the Fox Islands, Roberts Island and Little Briastone southeast of there . In Blue Hill Bay Tinkers, Tru•pet, Ship and the two seall Barge Islands.

In Jericho Bay, the two Spoon Islands, Southern Hark Is- -lands, supported populous colonies, with Halibut Rocks, and Saddleback Ledges with several s~aller ones were large enough to attract the shooters when the larger ones were broken up.

Further east, Petit Hanan Islands, the Egg Rock, Pot Rock, Cru11ple Island Egg Rock, Hason '- s Ledge, North ··L+bby Ishnd, Halifax and Hachias Seal Island.•

<The spaces were left in Norton's list. Mason's Ledge is probably that southwest of Swan ' s Island.)

Norton was occasionally inconsistent- in his use of na•es for is­lands. -For instance there is a Lower Harle Island in eastern Sheepscot Bay, an~ that •ay have been the one Norton eeant when he referred to

· terns re~ccupying Outer Green, -Lower Mark and Eastern Brown Cow by 1911. · · All of these are in Casco Bay. In another place he r~fers to ~Lower

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24

Hark in association with the •two Spoon Islands,• Halibut Rocks and Saddleback Ledges, which are all in Jericho Bay. The island referred to in Jericho Bay eust be Southern "ark, which he referred to in the li.s '-----~~~ for 1985. Again, Norton did not •ake it clear whether the •sri•stone Island• referred to is ip Isle au Haut Bay off Vinal Haven (where he reported terns nesting on. the three Little Briastones_ur near Swan's Island in Jericho Bay (where· terns have nested repeatedly in recent years>. It see~s clear that the Big Two Bush Norton referred to several times is in Huscle Ridge Channel, not in the Hatinicus group or in east

-Casco Bay, because in the above list, he listed Garden Island and Fishermans with it, and in another place he noted Coamon Terns. The presence of'Common Terns suggests inner islands, not the Matinicus group •

•••••••••••••••••••••••••••••• Norton's list of nesting islands for CO"MON TERNS, grouped by

bays, as Norton did, and arranged geographically fro• southwest to northeast.

The followin~ pre.fixes to supply additional in.for.aati.oa ... r....---­·1 11eans that' Arthur Norton 1 is ted the island as having b ~en used

as a tern_ Qesting island several ti•es between 1880 and 1921. + eeans that the island was tisted as occupied in 193t by

Robert Allen and Arthur Norton in their repGrt to the National Association of Audubon Societies •

* aeans that the i s·land has been occupied recent! Y.~- __

BIDDEFORD TO KITTERY Bu•pkin Is. Kittery foraerly i•portant * Beach Is. Biddeford 1 West Soose Rocks SACO BAY I Bluff Isl and +•Stratton Is.- Saco Bay (+ 11 600 Co••on, a few Roseates>

owned by National Audubon Society. WEST CASCO BAY I Outer Green I Inner Green I Junk o ' Pork I Western Hark * Clapboard l~~..J:..!!dge Faleouth Foreside • Nubbins - Yareouth EAST CASCO BAY A Lower Hark I White Bull I Eastern Brown -co;--

Turnip • Pond SBEEPSCOT I ·Reron I Egg Rocle

- HarpsNell

BAY TO S"ALL'S POINT

off Popha• Beach

• - -·

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I Bl .ck Rocks + Sugir Loives - Phippsburg (+ 1,100 Coa•on)

·· (+ 150 Rosute> BOOTH BAY/JOHN'S BAY Di•iri scove

I Pu11pkin Knob Thruac;ap Cuckholds - Southport 11USCONGUS BAY

Shark Rock I Western Egg Rock I• E~stern Egg Rock *Killick Stone

owned by Nat. Audubon Soc.

Crotch in Broad Sound, Breaen Nubbins in Friendship GEORGE ' S ISLANDS

Shag Ledges Sisters

Brothers MUSCLE RIDGE - PE~OBSCOT BAY I Clu Ledges_ I+ Garden <~ 1 1 000 Coa•on) I 11;arblehead I Fisher•ans l+Big TNo Bush <+ 200 CoHon> APPROACHES TO PENOBSCOT BAY I Metinic Green

H "etinic I+• Little 6r~en

(+ 300 Arctic ;and Co•aon) (+ 600 CoHon>

<• L;arge Green - te•por;ary> I Nooden Ball I Platinicus Seal · owned by Fish Ir Wildlife Service I+• Platinicus Rock <+ 1 ,000 Arctic) . owned by USF&rW Service. WEST PENOBSCOT BAY I Goose Rock I Robinson Rock I 11ou se Is land

Hardhead EA ST PENOBSCOT BAY I Nor th _Hay~.n._E_gg Rock I Sloop Island Ledges

Co11pass Island Gr;ass Ledge Spoon Ledge ...

Barred in Deer Is l e Thru•cap in Brooksville ISLE AU HAUT BAY -"edrick Rock :-3Jreen Ledges

---- ·· ·-Green:.. Isl and - -- --'---- -Little Hurricane · ..

25

\

•

'

.--..

.. --·- -·-------- ---

26

Hay lshnd I Robert's Island I Little Briastones (3) JERICHO BAY - ---------I Southern Hark (populous) I Little Spoon <populous) I• Big Spoon <populous>

Popplestone Green Islands Green Ledge

I Halibut Rocks I Saddleback Ledges #+t Briastone (+ 300 Common> (unlikely to be off Vinalhaven> Mason ' s Ledge

* The Cow Pen BLUE HILL BAY Tinkers

I+ Trucapet ( + 1,000 Coaaon> I+ Ship (+ 600 Coaeo~) I two saall Barge Is Saiu tt ynose/F-Ly.e__ Brook Jin * Hub Is - Haunt Desert Runnell Cove - Trvaont FRENCHMAN'S BAY Egg Roc:k tu PETIT HANAN

Green Isl and WESTERN BAY

C~ 800 Coaaon and Arctic - owned by USF~NLS> (owned by HOIFish ~ Wildlife)

t+ Egg Rocle by_ Cruapl e Is. (+ 600 CoHon> I Freeaan ' s Rock Ladle=Nash - Addison Flat

JONESPORT REGION Pot Rock

I Egg Rock HACHIAS BAY/ENGLISHMAN BAY t North Libb y Is. I+ Foster - Roque Bluffs ( + 1200 Common and Arctic> I Halifax fff fffff ff****~~··············

· : - -----··--·· ----·-·--"'----

\

'

•

• ••

27

Norton's hand-written list of nesting islands for ARCTIC TERNS, .rranged in his usual ge_o_2raphical order, as followsr

- ·

1873-1889-1916, 1917-1918. 1928 1897, leave

Junk of Pork Heron Id. Black Rocks 1897 = 16 <Means they--1.2ft

1924· -in 1919?)

Inner Sugar Loaf Egg Rock Popha• Daaari scove Id. Pu111pkin Knob Near Bristol Muscongus Bay

E. W. Lit Egg

1895 - 1897, leave - 1884

1888 - 1890 -•

I

1884 - 1897 1898

1895

<May aean Eastern, Shark

Western and Little Egg/Mosquito>

Little 6reen Id. - 1885-1886 - 19 Metinic Green 1aa3 -Matinicus Rocle · 1865 -Ship 189~ ---- -·· ---Barge • Truape Jonesport Egg P102 Freeaan's Rock Foster's Id. 1905 1931 Gliby Ishnd "achias Seal Id. 1879 - 1939

.

The lists should not be taken as indicating discrete populations of terns nesting at _these eany places. They suggest, instead, that good tern habitat exists in these places, as terns have bred successfully there over several years. Studies of gulls and terns suggest strongly that birds steadily exchange across regional •borders,• and once they leave an island they aay •ove a long distan~e.

Probably the •ost promising places for intervention on behalf of Roseate Terns are at the Sugar Loaves in the aouth of the Kennebec River <where all three species of terns ~ested until recently>, and at Ship and Truapet Islands in lower Blue Hill Bay which were successful terneries until the 1940s.

There is less_p,ro•ise of quick returns of Coaaon and Arctic Terns to the following places, but at least as •uch need:

a. eastern Casco ~ay; b. the Junk o ' Pork, Outer Green Islands area in southwest

Casco Bay; ___ . _ _ c the region bet~een Biddeford and Kittery d. the Isles of Sh~als <The Audubon Society of New Ha•pshire

has undertaken a project there.> · ---------·~;: Mac~ias Bay at Halifax, Foster, or Libby Islands.

·-·- --- ·- --·-- --

'

. ·/; . .. . ,.,. .·'

• I

..:.

-/

•

l.: _ _ .E/£.fe_1..J.,.OAJ1N_f, .- 'P;49~s AR~ t4RTl4u~ f!Jo r-fon1s No-:r~ .. . .:l

~ ~·:rkd,o44 ~I~· ·~·~.(~ f.. ·-1U~ ·~ .. ~".: . ~ .. ·.·. . ~--~ ' " \ .

:Bluff ioland •.

. . .~ . . ... ,., . ' . .

MAINE TERN COLONIES Ill 1885. . . ... ~ -..

Saco :Bay. . .=.:· ... :·, ·. . . . . . .. . . :- . . .. ·;,. -:~·:"'.:. ~ . . : .. ·.. . ,,

• · ... ·_.:: • ·: .. 7 ... : .:·: · -:: ~.:<.: . _. ....

Case~ Bay.

.. . . ·. .. ; . .

.·· . . · .. · . :·;" -

• . . -·:,-~_' .. _/- .~,> .. ·.-~.:-=:.:~ . . . ... } ~-.. :.: . . . - ... . . . -· : : . · .. :

Uppe r Green Islands.(2) • -· · .-:.7es t Brown Cow

Lower Mark Island

Inner Green Island

Outer Green Island

Jttnk-o:f-pork \

V/hi te l3u1l •

Zastern l3rown Cow.

Heron Islands

. \ -· -·------ -

Phippsburgh.

3 Egg Rock.

' I

• 7 -

Black Aock

(D:ima.s cove .1 sland )

Pumpki n Enob

F~ocrites.

T:ta.rumbcap

Shark Rock

Sheepaoot ~ and .Tolm's B~.

Dr.T.K.:Brewer reported a colony on this island (1884,Watre Birds N • .Am II,~02).

~-congus ::Bal".

Eaate~ E~ ·. Rock . :~ .. ·.·:.: . . : ._ . - .. .

Western Egg Rock · .· .: ·

Li tUe Egg Rock .

. . - .. ... ,• - .- . , . .. Shag Ledg~s

Si stars.

. . .. :+ .,,,, ..

••• ltetinio Green l3lmid

Little Green Ioland

lUs Green Island

ll:ut Pezaobscot Eq . . : . .

::-· .. ·.

. -. - •. · ..... . .. . ... . .~. -~:. ··.~· .. -~:·. :·; ·. ·. ·.: .... .. .

. · ... :· _: : ..... . : ~ .. .... . . .. . ... '· . ..

- -·~.··. :: ::: .. . · ...

. .. - · .. .. :::.····

, .:.-.,,· .... · ... . . . ... . ·::·· .. ·.

, .. ' . '.-- .

. . - - - .-· --:~--:-::.: . ·. :.' • .·. ';

.. .. ----:Sig Two :Bush

•

CJ.run -~edges

Go.rden Island

Fiohe-ri:an•a Island

Little Hurricane.

Fox ~Islands; ·

(Ceased about 1ea~ )

., Jledrick Rock

Green Ledges

-Green Island ~

Egg Rock

Compass Island

Grass Ledge

Sloop Island Ledges

Spoon Ledge

Robinson's Rock

Goose Island

l!ouae Inland

~ .

I Rardheag

"lla'finiaus Islands

".:: ·:,·

) .

--

· ·-- -· -----Ray Isl~d

Robert' a~· Island ..

-~ittl.e :Srimstonea,(3)

. ~ . . . '

'

• ,.

·' .. · (:.

. :~~\_ .. , '

'•

\ .., Little S~oon Island

Big ~oon Island

.... ' · . . :

IS-S'S- ... ~- ' .... .. . ... · :·· . . . ·:·. . . . . . . ·. ... . . ... .

Jericho l3ay.

· . . . ,· -_:· ;·_ :,.:-- .. ~ :. ·:. ·. ··.

:. ·.· •!· .. . ... \ .

· Green Ledge · · · · ·· . ;· ' : ·."-:." :.·· .. . ·· ·, _.:f~ ~<: .: .. -....·. ': ·. · .. . .. ··.··:. North Popplestone

Southern 'Uark Island

F.:\.libUt~Rocks~~­r

rl

! Saddlebnc!c Lcd~o

Tinker's Island

Trumpet Island

Ship Ialkd

The :Sarges (2).

• Gre~n Islands~ Ee.e Rocle

Fot i-toclc

Ladle

Egg Rock

...

:Bluehill :Bay

Petit Kanan ..tiegion

Jonesport Region ..

'Jlii11'Pi'1 /¥11¢?' Free~' s Rock

' '

·: ..

·Englishman' e :Bq, (or •Jlachias l3q•)

l'orth Li.bby Island

. . . . .

1 -

31 ..t

, ·A : i

'

• Dltri?ie; the ye~rs of 1886 and 1007 a wholesale slauizhter of terns was . . .

co.rried on in uusconBU·~ .. :Say", -. Pen~bsc~·t :se.Y·. · lfat1n.1cus SeaJ. Ieland and

· --·-·-··-t_h_e_ V_o_o_d_e_n\ Ball~ Blue Rill an~ Jerich~ :saY:J.

populous colonies were anihilated.

Severa1 of the most

·- - --·----

•

· .. , . .

•••

A chance in "fas hi on" in milline~, and the I>O.SSSBe of a la\1 for the

protection of terns-1n--:-ua1ne~a~eed by the legislature of lei!> caused

a ~ause in the destruction of these birds.

Survivors from the persecuted colonies joined other established

colonies and some of these bece.me. populous a«a.in.

were kno\711 at the following places. \ .

...

In 1890 colonies

. ..

· · · · :· ·: · ·· ~.· ·' :··:·:: ,. : ., '··~"'~~~~~~~if J.l~H~·;:~l~t~~":· ·. :.:~ · :·:· ·<I~;°~( .. .. ·. . · · · <_: ... ·~ .. ..... . · .. :~~::~/::+~~~r-;i4i~~~::~~: . ·:.::·.·:: .:~~~ : : . · .~ · .... .. ~~-!:·;_\,-. .

. . . .. •,'

'

... •· .. . 1 ;: .

?· .... .I ,, .'\..

·.,.: .. . . ' .::· :.~: .... ::.£~-:·.:-':::-~- . -.. -.... -.--~~--~-~ ... -: -: ,-.. ~:-~· ·.-. _-; .. -.. -.. -,·- .. ---.. --.' ... -.... ·.-.. -.-.· .. ~ .. -.... ·. __ .·· .·.·.: _ ~.,:·:.·.;.·: .·.~ .: .• :· .. ;..~_ · ... :.: ... '.·.·.··.~ .. -.-... ~··.:.·_ ;.. .. · •. · .. : ~.-~ . -. ..< ....... .. · .. :·:·~~· ~:~~~; .. ~:?r~: __ :· ~l:'.t:\~ ... \!· .-~· : .. : - .: . .-: . . "' ... ~

.. V.aine Tern Colonies ·in 1890~

·, ..

I \

Bluff Island

so.co '.Bay .... '.".: • .:.: .. ~: ... ,~: .. -.. ,._ .. : . ...... .. . . · . .

. .. :' . . . : ''.:-./: :>~ · :~:'.!\:.:Jtfa~:.·.;:;)_~~~>.::;.·~:~·<· .. :~:.::~~.~ ::'.· ,; .. _: • • .. .... : . . .. ... ·. ; • . • • I'.•:. • • • • • • • •• ·

Junk-of-pork Outer Green Xaland

enoco __ 'Bay .:·~:·~~.:~·:=~i-?~~-:~??~:).~=:~~::~r~::/~:y:·:.- "' ... . , ·

Lo\7er ltark Island- _ -·-· . \lhi t e Bull.

Eeron Islands

·::, EGG Rock

--

:Slaclc Rocle

. Pumpkin Knob

Thrumb Cap (?)

Eastern Ege Rock

Westwrn Egg Rock

Phippsburg.

Sheepscot and J9lm's :Bays.

Kuscongua :B~

Penobscot :Bay

Uetinic Green Island

ratinicus Rock

i~c:.rblehead Island

Fisherman'~ l6land I ~ Fox Islands,

Saddleback Ledge Green Ledse

•

·, ... ·.·· ._ ~ \ . -Green .. Islar.di .•

..

. . · .. . , ; . .

. . : .... ·.··· ..... . • -

'

... •

\

Trumpet. Inland

---Ship

., ., The :Barges • • ! ~

..

:Blue Hill :Bay - ... .. . • •• •t

. '! :" :: . . ,·. . -... · :· . ·\ .. . •. . .

.. ... .,,. .. .

·.· ;.:!: .. . ~ · ..

.-.:.

Petit .Kanan to Cutler.

Green . ..±s1nnds. ---- -· Ecc Rock, (Crumple

.. }:s~and)

Freemants Rock

North Libby Island

Uachias Seal Island.

Gull Rock

-:. · · .~ ..... :' ... , ··..: . :' .~:~·~ . :

. . , .. '. ~ : · • . • I • ••,.

. -. ... '·.·: E . .... -

. : . -..

\ .

..

. . .

· ...

. ' ... . . .. · .. ·

-: . -: ..

• .

.· : . .

.... , .... 1· f • • ' • ... ' . :

. . . . . . . . ···· . •. .. ~ · .

• ·.~ ~·· -· " '

·~ I( •'\.

' \

.. . . . .. ·.

\

' , . .. . ' 1 · .

The demand for plu.mace · was revived,a.nd the swnmer of 1899 saw the

colonies \lo~ Outer Green Islnnd, .the Phil'psburg colonies and Pwnpkin · . \

Knob swept out of eXistence -r·or a · number of years. the · · ·

---- ---Pumpkin Xnob,t.bd

Phi~Dsbura colonies were p~rmanently destroyed; Outer Green Is~nnd wac

after a fe~ yeo.rs slowly repopulated,but throueh severa1 causes led a ------ - --··--·

fluctuatin~ ·existerrce until a few years subsequent to 1918,when the

Iola."lcl nas ta.ken full posession of by the herring BUlls.

The summer of 1900 showed the following colonies of terns on the

coast o"f Maine.

\ '

•

:·- ._ .... :..;.: ... . ,. ...... ., ... .. . .. · ·•

1; ·:;,~··. · ·, 'f~~i'tj~;:: ~:';&~}~~[~,;.·:: .. '' ·.:7f 7;\''t · .-,~~~: :: • '.:~"·~~;::~~~~~;:''· ·. '.

. .. .. . . . . . . . . .. " . . . . . .. ·~ . . .. . .. . - .- . _... . . . . ... . -. . · : -: .... : ......

.. . ·'- J • ... • • •

. . . · . . .._. . .. ....... ··.·-.. . .... . ·:\~~i·:.> ·:· .. - ~~\~·~~. /~:~_: ... :::,: .. .... :;.~ .. t::-.:<~.~-': ·:: -. - . '

I

:J ~ .... :) .· · . ... . . · .... ..

llaine Tern Colonies in 1900. . . .

\ · .. ... ·· "-t•.~· ': ·.·· .... · ... ·~ ... :;;.. .. ·· ... · \ .... . ·· . ':: ,. ,1 •

\ Bluff Inland.

Casco Ba;y

Lower Mark Island

... - 7lfil•te Bull

MusconBUs l3ay

Eastern Eee Rock

Western EBB Rock

Penobscot Bay

\ Uetinic Green Island

Matinicus Rock

•

, l.!a.rblehead Island

Fisherman's Island

Fox Islands ,

Eas Rock

(?)

(?)

....

sioop Island Ledges

Jericho l3a;y

Green Ledge

Popple stone

Saddleback Ledge ·~­

Ha.J.ibut, Rocke

Blue ·-ru.11 Bay

\ . ~· : ...

..... , ... ·. ' ·. , .

·.

... ·- . ·.. . ~~.

,.

.: . ,

.. · .

I

' · .. '.

.·

• :·· # :.

'

~~~~ !.--:;.~. ~~~-~- ~ i•. t.·· . .. . . ';-" , .-... ~)qoo .-· -.

• ,,.~~ ..

\ '

'Liiffs<I lltlttsl Freeman's Rock

North Libby Ie;Land · . ·. . ', ;·· .: ·.. . . : . .

). . .. . :· . . ... :, ·: : ' . : ... ·.: .

\ "

~chias Seel Island·. ' . .. : ·. . : . . . . .

. ·. ·-: .... :·· .. . . .- _.. · .. ; .. _ ~-:· :._: '-: . ~ ~ .

Gll:.11 Rock .

. : : :' · .. : .. ··.:. :.". ·.: . .. . . . . . ·······.'.

\ ," . ·: . .. : .. ' ·' .. :.. _·~.·'..'.- -7--.-__,:....,._ __ _;_ __ . . ·.. . .. . :·

' ' • ' . ·.,'I: • ·' ' '"" ' " • . :. · . ..... ·: . .. . . . ·-:" :

From the year of 1900 terns were little molested .by man,having been

protected throuch the Thayer tund,which shortly gave rise to the

iraticnaJ. Asooci~tion of Audubon Societies. . This or~anization. \ . . . '

throue}l the employment of local guardians attended to the enforcement • . •.

of the "model :Bird Law" enacted by the lta:i:ne legis.la ture of l~Ol.

Gulls shared the benefits of "tlrl:~ care,and by 191~ had increased­

the extent where beginning ot their extension ot range was noticed.

Ha.vine reached this state ot abundance,their extension of colonies

vas rapid,and their encroachment and replacement of the colonies of

terns continual. The expelled terns bagan to occupy smaller . .

islands and ledgee,,whiQh were frequently unsuited to their need,for

variuus reasons.

The f ollowine i&lands and ledges were known to be occupird by terns i

in 1911~ -·-

.. ·

. .. : ._ . : .. .-:- ...... ·. . · ·~·-. . ...

... . . , f • .:.::·:~

'· \

:Bluff" Isl:md

4V •

::: ·· .. . · .=·i·_ ... :-: .. ·•·· :_ '\\ .. : .... ;:L"~/~L~~;c: ·.:_:~'.-~t:tr.~>>::-::,~: ......... : .. ;: ::~::~ ~· · Coloni~3 8ocupied in 1911

Sacd1 :Sey. ' . • > .. . ·.· ...

: .: . \ . ,;:·. ~ . . . -· Caeoo :Bay .. ' · } ... :.: ·:: : . .. _: . ::~.:-. : .

. ~ :

.., 7

: ~-· · : .

. .. ... . •.:· ' .· ; :: : ·:· ·•

• ! •• Cuter Green· Island· .:

(~o ·record in 1911; occupied 1914,unsuccesa~u lly).

-·- - ---------- -· ~ Loi•:er j.!~ rk Island.

XuscoriBUs :Say.

Eas tern E~ Rock

dcstern E33 Roe~

Penobscot :Bay and ilatinicus. \ ···· - -- · .. \ ' ...

l!etinic Green Island

l!:!tinicus Rock

l!a.rblehead Island

Fishernmn•s Island

P.obinson•s Roe~

Goose Island

rouse Island

Slopp Island Ledees

C~nel. Rock

-·-·sou·the:-r. Mark Island

S:id ~lle~ack Ledee

(No record)

(No record)

. , .•

. ~ ·

(No record 1911; occupied 1914).

(No record 1911; occupied 1914)~

(No record 1911; occupied 1914)-;- .

jericho Bay

• p--, i ibu ~ Rock ~

The :Ba::-ges

·-

i~ t! 'I

·· .. ;; ~· :: ·: . .. .. . ....

·.~. . · 1 .. ~

··. ·: · ... : ..

--· .........

.. Po tit Kanan to

\

Ecc Rock,Crumple I3land

Frcem.an•s \

Rocle

I . . ' ~ .

. . .• •' .. : : ... :: .. : North Libby Island··._ ~ach1ae ~eal lele.nd

Gull Rock

;

\

.. · .. · . · .· ...... ..

",' :: -~-:.-::.. ~ .

·.· : . . . .. . .. ... . :..' ;;. ..

: .. , .... ·'. .. ::. < fJ/-~x~~ ~i r~~t~~:~:·~

V o I '

.., ·• ··;;,r ."·~ ... :> . , "' .. .. ; \o ••• • • • ..

~: ... . .. ,, . . :. ;.~ ·.·.- . . .. . . . ·~· .. · .. · . . .

Cutler.

.. :·· ..... ...

.. .. : ~ ·. . . .. '.

... ··-·-----=-----'---~ .;., . '"' .. .

··:.,:-~::~. :·,·.,.; . . ··

\

·-· • .. .. ·\ . . · .. ::· .. . _,. ... ::

•.

-·

,•I • ,t• •.• ~.-.. .. ·:· ... . .

•

.... .. .,.t:_. .. ·:·· .

.. ... .· .. .

... --- -=-

'· ...

..... , · .. ~r· .· ···

· ·:

. .. ·.:

\

Stratton Isle.rid

- Casco :Say.

Pri~ce•s Point Ledee

. ·- ... - --{ffshe rmen -- - - ··----- - --= reported a col~ny on Flae ~d.).

Lo:.1er J..!.3.rk Island

Pond Island

. Phippsburs • ~

U:pper ~uaa.rloa:f' •.

Lower Susa.rloaf

Penobscot ~~

!.:e tinic Islnnd

?~atinicus Rock ,

Garden Island

Little Green Island

Jericho Bay Reeion

Eclibut Rock

T;:o :aush

'E ri.:ns tllne

:Blue Hill Bay ::

Tru!:Ipet island .• ...

" .1:: . . Shlp Isl.o.."ld

Weste;~· :ad~· _: ·· ·· · ~- d~'.>~Vl~~~t-~~t0?!:i~'.;J:tt .;::.-., 1f!f ;J~;;-:,\t~'. Green Island

Petit Hanan ·to · Cuti'ir~--:-;~~"7{ :. · · .... · ·

:. ::.~f~:s~f~~~:{f?.#~~f:t~t>::·. < - ~-~w~r _::· · -:::f~;::.'i>: .. ) .· :·.-_;: ... ~..t. ·~ · ·~-c~~ ,v.,J.. -~ w....{-~ • . :E~ Rock, (Crtimple · .Id.)

. :·. o •, I

. "i --.-. •· w•. ~-_.. ... '.· . . : ' . "(~ •.. ~-· .. . . . ·.i· . ·.·,.. ..

~·, q 3} . ·. -.. :<· ·' · \ ..

. . •. :r. :' • .. :

-•

. . ::·.

·~~~ · !::~~ ·

\ Frccm:::.n' Ef \Rock.

::s'ooter~s

Jl~chias

·, . ·,

Island \

Seal l3land .

Gull Rock • .

. . . .. (Petit Jkl.nan-Cutlor,Continued)

·'·' • : •. J • . • • • •

-.· - - ,--......:.._, · •. ·.;. :·.·.:. .: ... ~.~-·~ .· .. ... · .~ .-:: · .... . ·. .r .~ · ·: ·.. ·· .. . :J:' , ... :: .. ·· . ."· ~"'.'.· . • :.~~ . ... . :,:.:.· .~ .... .: .... ... • , •••• , ... • :. •••• · ·:. ;: •• • • - • • t • • • ••• · .- .·~~.:· ••• • -.: •• ·., .-:: •• : : : :_ ••

t • • • • • : ... ~:: : :'· .. =~.··.: .. ·.. . . . : " t • • • • • • • ·~. . • • .. • •• .. · . ~. : . . . . • • • .. . ··t ----. -,~ .. - . -• • --·."".-~.-. --'-"".-••• •• • • •• • • ··~ ·~:. : ·.·· · : :·, ... • ••

·.~-== .... : .. ; .... ·.·.: .. ·.:·.·.:· ~.·.:··.·· .. _; ,· ... 1:•-1.· :.i:~··, : ~·= •;· ............ - ::.- ·:.:·· : .. : .. : .... .:. .. ~::':':.: .•• ~:'.,· .. ·~~: •. · .. :;·_~·.··~ ·'. ,. :: .. :···--·: ~~_,s·:~=·-\;~:-~ :.· ... ; -~_:: ~.·. :. ~·· .. ::. . · . . ·. ;-~~-' . .. .... ··· .. h~- - ; ...

-------~ ---------·

..

. ..

. '£i~~~~k;'.~;J_~,~~~. ::: ~ Jt. ·:C · .....

.. . . . · ..

·..;

41

APPENDIX D. SUGGESTIONS FOR FIELD PARTIES

STANDARDIZED TECHNIQUES FDR CENSUSING-AND-HEASU~ING BREEDING SUCCESS

Dur •anageaent plans have two objectives within the goal of •aintaining and increasing the populations of terns nesting in Maines

a. to keep track of the health of the populations and the success of our efforts at protection, by aeasuring reproductive success at is-l ands Nhere we have resident work . pa_rti_e_~i _ _ _ ·- •

b. to keep track of changes in the population as a whole fro• year to year, by censusing nuabers at all tern nesting .islands.

Detailed Studies to be made at Islands with Resident-Nork Parties. Unless observers intend to •ake repeated visits to individually

•arked nests, they should aake only one, careful toaplete count. Sub-·-­sequent counts aay confuse the issue as during the course of the season, soae pairs abandon when their nests fail. In addition:

a. new nests will appear belon~ing to inexperienced birds breeding for the first -- iiae,..-.in..d · ~

b. if the ternery has been disturbed, repeat nestings aay appear through aost of June and into July. If the new nests are counted as they appear, they will tally up to a very i•pressive, but not very help­ful total.

'

Sugges~e-~ Prq_!:eed.ures for Counting Nests. 1. Esti•ate the nuabers of birds flying over the nesting area

<see te~hniques proposed below) and conduct a coaplete nest count. 2. Nest counts are best •ade by at least tNo people--WaT~ing

abreast at aras length systeaatically aaking sNaths through the nesting area. Plan routes ahead of tiae so that you avoid duplication and gaps. The census tea• should aake as aany passes as nece~ary to cover all nesting habitat coapletely. ~ne_. p~rs~.n should _record- data while the others count. Avoid making counts on rainy or cold day~, which would have negative effects on nesting success.

3. Make counts just before eggs hatch, during an annually agreed upon ten-day period between June 10 and 2S. Counts conducted after this period are likely to be inflated. If birds start at one island, but are disturbed, they ~ay •ove to another in late June <as they apparently did at Metinic in 1987 and Large Green in 1988>.

4. For colonies over SO nests, conduct a N•ark and recapture• sa•ple of the nests. The technique adds only a little extra work, and can provide a check on the accur·acy of both the ITT!st counts and the estiaates of birds in the air.

Mark each nest as it is counted <to avoid counting a nest •ore than once>. Use substantial earkers, like tongue depressors or flower pot •arkers. Don't worry about possible subtle effects of having your eye drawn to aarked nests , ·-and--do Norry about putting saal 1 objects in the nests as aarkers. Terns Nill re•ove soae •foreign objects,• such as your i~onspicuous aarkers, and you Nill get an inflated count.

After you have coaplet~d a count-and-aark survey, - search a sNath or transect running diagonally across the nesting area, recording the

•

•

42

nu•ber of nests found aar.ked and the nu•ber found ~n•arked (aissed in the first search>. Use these nu•bers to calculate an index for the to­tal nueber of nests, called a Peterson or Lincoln index, as followsa

Say you found 86 nests on the •ain search, and 18 •arked nests and 4 uneark.ed on the transect. Divide 22 <the total> by 18

__ <the nu•ber aarked>; this gives you 1.2. Multiply Sb by 1.2 giving the index total of 103. Re•e•ber that because you • issed sose, the correction is upwards and the correct •ultiplier will be 11ore than 1.

- ·-- -- - - --· ··---· Estimating Reproductive Success.

Ian Nisbet and I <1972. •"easuring Breeding Success in Comaon and Roseate Terns . • Bird Banding 43(2):97-106) found "that we could establish the nu~ber of chicks per nest by either:

a. putting up a blind and count ing the chicks visible at each - of several sa•ples of nests.

b. setting up fences around several samples of about twent y nests each, 11arking and counting the nests within the fences and later banding chicks, or.~-~~

\ a. USING BLINDS - Good data on reproductive success can be ob­

tained with relatively little disturbance, by setting up a blind at each of several places fro• which 10 - 20 nests can be see11 clearly. Nests can be urked with tal 1 ~takes during the.. incubation' stage and then eoach nest ... sU_e repeatedly checked fro• the blind for the number of chicks loitering at it. · Twenty to forty well-•onitored nests will give good data on chicks produced per nest.

b. USING FENCED PLOTS - Fence selected ··areas; cOUrltand mark the nests . When the eggs have hatched search the area very carefully, band­ing chicks <record the band-nu•bers). A couple of doays later repeoat the search, recording band-nu•bers of tall banded- chicks and band and record any chicks found unhanded • .. _Again a •Peter:son/Lfncoln Index• gives a total of the chicks surviving to the ti•e of the first banding trip.

Co1111ents. You should wait until nests are being incubated before putting up

the fences . Otherwise the birds recognize the differen£e between •in­side" and •outside" and lay their eggs in scrapes outside the fence. Make sure that the wire mesh will not allow a chick to get part way through and not be able to get back. Be sure that the botto• of the fence is free of places for tiny chicks to slip through and not be able to get back. The parents aay not have senset!nough to feed the• outside the fence . Avoid having the fences run through dense vegetation, be-~ cause chicks press theaselves under the •thatch. • These chicks are very hard to find and it is distressing to step on one that you haven't seen.

Another •ore detailed-body of infor•ation can be got by •arking chicks ~s they hatch (banding or putting a s•all, biodegradable tag on one wiriq:.and banding the• later). Then at regular intervals Ctwice weekly (s adequate) we igh- and •easure the chicks - the length of the--­•hand-plus- priaary-feathers. • These ••asureaents give ta growth-rate,

• 43

which provides a high-grade •easure of the qual i ty of the local f~eding grounds - or the parents • co•petance.

We need to have banded, known-aged adults for this study.

Censusing the Many Islands not Subject to Detailed Studies. In any year in whi~h we run a coastwise census, we eust estieate .

. _J\u•bers on all occupied islands to follow trends in the tern populat i on, because the birds •ove around so •uch. As shown by •odels tested by bio•etrician Willia• Bossert of Harvard, we can use data wi th as •uch as 30% "error" to identify population t r end~ ove~ se_~[al_ d~ca~~~.Ne can gather data co•parable in accuracy to nest counts by •aking careful esti•ates of the numbers of birds flying up over a nesting area.

Esti~ating the nuabers of birds in the air over a nesting area is the •Ost practical way Of keeping track of nu•bers over a large portion of the coast. Obs ervers should record the details of their eethods.

Esti•ating the Nuaber of Birds over a Ternery. In • i d June, <when •ost of the birds are i ncubating>, observers

should go into the nesting -area as soon as they land, and put the birds . up; -dao1-t~ l will fl ~ up. Once they are up, set about estiutin«i the nuabers of birds fl ying carefully and quickly, counting by groups of . •tens• or "fifties.• It is i aportant to avoid dallying , because those that go up soon begin to settle and drift away. Don't let so•eone dis­tract you by calling your attention to so•e rare species.

You should esti•at~ the nueber; of bi rds loafing in flocks on the ~shJ>re separately. These are non-breeders and failed breeders.

Observers should test the•selves to establish whether their estiaates of birds in the air are equal to the nuaber of nests, higher or lower - and by how auch. Observers can calibrate their estieates by coaparing the percentage of the air estiaates with the estieates of nests on the island. It is also helpful to spread differing nuebers of gra i ns of rice on a black piece of paper -.md "fix• the nuaber (gestalt> in your eind's eye. Many pe~e can . l ear.n this trade easily Nhile others can ' t.

Experience, Nhich is priaarily paying attention, and practice will help to refine accuracy and cons i stency. Kost i•portant, consider what it is that you are tr ying to learn and what level of precision is neces­sary to l ear n that. The difference between lS and 25 is iaportant, but t hat be tween 75 and 95 is nuch less i mportant, as is the difference be­t ween 650 and 675 . That is one aeani ng of logarithaic fun c tion.

A quick way to •eas ure breedi ng success r equires two visits, one i n ai d-June to e s tiaate birds over the nest i ng area (appro xi•ate nu•ber of nes t s >, and one i n l ate July t o s ee-vhether the te r ns are still pres­e nt and to count fledg i ng chicks. Chicks ga t her at th e shore sooA-after fledg i ng. The nu•ber of terns over the island on t he s econd visit r eflect the n u~ber of pa i rs tha t have chicks, as failed birds leave.

These data allow you to es tiaate whether the breed i ng season was a disaster (no chicks ~,---poor <•aybe 10-20% success>, or good. This is useful, _because breed i ng atteapts at •ost unsuper vised islands in "aine have ru~~f roa 0 to 20% success .

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.. - . ···------------ -

44

APPENDIX E. HANASEMENT PROCEDURES

The following •anage•ent activities are intended to i•prove condi­tions for successful .. breedi..ng at the colonies chosen for intensive •an­age•ent.

1. Breaking eggs and shooting will not be effective in driving gulls fro• a nesting island once they have bred there for several years. Managers •ust poison adults · and if gulls are to be poisoned, they should not be disturbed beforehand.

Re•ove nesting Herring and 6reat Black-backed Gulls fro• the - - .. island by poisoning. Success •ay require 2 poisonings per year for·two years.

Support the poisoning progra• by shooting adults and breaking eggs in nests found after the po'isoning to prevent resettling.

As aany as l excursions per week •ay be needed during nesting season to shoot gulls and break eggs.

2. Re•ove any •am•alian predators such as rats and feral cats. If •ink repeatedly gain access to the island, the island •ay not be suitable for •anage•ent. ~ .

l. "aintain a field party ca•ping on the island wherever possible ' and post the nesting area to li•it visitor .iccess. No .icces's for visitors with dogs even on a leash can be .illowed during th& nesting season, Hay 15 to August 15. Other visitors •ust be supervised .ind stay on •arked access routes.

4. If the island has ~een overgrown by bushes ~Baybirry, Cherries .ind Raspberry> or grass, it •ay be necesury to •ow., burn repeatedly and apply herbicides to create openings. Chicks need so•e cover for shelter fro• sun and rain, but no shelter will provide protection fro• preda­tion.

~. Use of decoys and recordings of calls has been successful in attracting terns to e•pty islands, but these are probably superfluous where a feN terns have settled.·· -

6. For the long ter•, il ~ill - be helpful to take political action to keep •second-holle··h""ousing develop•ent off existing or potential tern nesting islands. This involves seeing that all tern-nesting islands receive special consideration during the environ•ental reviews by state agencies such as the Department of Environ•ental Protection <DEP> and the Department of Inland Fisheries and Wikllife <OIFW>. Citizens can insure that local ~uniciple governments and plann i ng boards are aware of the nesting sites of seabirds and waterfowl within their jurisdiction.

7. The •ost effective protection is provided by owning or obtain- . ing conservation easeeents or eanageeent agree•ents for nesting islands.

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