176 saving the eastern loggerhead shrike

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ONTARIO BIRDS DECEMBER 2008

IntroductionThe Loggerhead Shrike Lanius ludovi-cianus (Figure 1) is both a songbird and abird of prey, a combination unique toshrikes. Because it lacks strong talons tograsp its prey, the black-masked birdimpales its meals on thorns and barbedwire, earning the nickname of “butcherbird” (Figure 2).

A little smaller than an AmericanRobin (Turdus mig ra tor ius), the EasternLoggerhead Shrike (L.l.migrans) is one of11 subspecies of Loggerhead Shrike

found in North Ameri-ca (Miller 1931).

Saving the EasternLoggerhead ShrikeFifteen Years of Recovery SuccessElaine Williams and Jessica Steiner

Figure 2. Shrike preyimpaled on a hawthorn. Photo: Mark Wiercinski

Figure 1. An adult Loggerhead Shrike in the wild.Photo: Ethan Meleg

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However, recentwork recognizes only9 subspecies (Yosef1996). It was once acommon sight acrosslarge areas of Manito-ba, Ontario, Que bec,and the eastern Unit-ed States, inhabitingcattle pastures andshortgrass prairies,where it could easilyfind the mice, crick-ets, and snakes thatform its diet.

Like most NorthAmer ican grassland bird populations,however, shrike numbers have beendeclining steadily. Over the past 40 years,Loggerhead Shrike populations shrunkby 70% (Butcher and Niven 2007), withthe eastern subspecies showing the steep-est drop. Since 1970, breeding popula-tions in Canada and the northeasternStates have been nearly extirpated (Pruitt2000).

As a result, Eastern LoggerheadShrikes have been listed as endangeredboth federally (Migratory Birds Conven-tion Act 1994, Species at Risk Act 2003)and in several provinces, including Ont -ario (Endangered Species Act 2008).According to 2008 estimates, there arecurrently fewer than 40 known breedingpairs across the country (K. De Smetpers. comm., Wildlife Preservation Can -ada unpublished data). Most are concen-trated on the limestone alvars of Cardenand Napanee in southern Ontario (Fig-ure 3), with a few elsewhere in Ontarioand Manitoba.

What lies behind the dramatic drop?A number of factors have been suggested,including habitat fragmentation, pesti-cides, predation, availability of prey, climate change, and collisions with vehi-cles (Pruitt 2000, Environment Canada2006). To date, no “smoking gun” hasbeen identified, although more researchis required into mortality factors on theas yet unknown migration routes andoverwintering grounds (Smith 2001).

Figure 3. Map of the core breedingrange in southern Ontario.

Present corebreeding areas

LakeHuron

Lake Erie

Lake Ontario

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A Strategy for RecoveryIn the face of plummeting shrike num-bers, a National Recovery Plan for Log-gerhead Shrike was published by Johns etal. (1994). Its goal was to maintain or enhance wild populations of Logger-head Shrike nesting in Canada to thepoint they could be removed fromCOSEWIC’s list of threatened or endan-gered species (Smith 2001).

Despite very limited funding bet ween1994 and 2000, the multi-agency Recov-ery Team charged with implementing thePlan succeeded in achieving an impres-sive number of the measures it called for.These included: monitoring the remain-ing wild population, establishing a cap-tive breeding program, assessing thegenetic make-up of the wild and captivebirds, and launching a habitat steward-ship and restoration program to protectdisappearing cattle pasture (Smith2001).

The financial picture brightened in2000/01 when the program secured sig-nificant funding from the newly estab-lished federal Habitat Stewardship Pro-gram, as well as additional funding forother recovery activities. Then, in 2003,Wildlife Preservation Canada (WPC)signed a five-year Conservation Agree-ment with Environment Canada-Ont -ario Region, under Section 11 of theSpecies at Risk Act, making WPC thelead non-governmental agency responsi-ble for coordinating all aspects of therecovery effort in Ontario on behalf ofEnvironment Canada.

The five-year agreement ensured apredictable flow of cash that allowed usto plan our work strategically. This paidoff with strong results, particularly fromthe captive breeding and release program.

Captive Breeding: Breaking New GroundOne of the priorities of the NationalRecovery Plan was to establish a captivepopulation of the eastern subspecies, butthe cost for such a program made it con-troversial. However, when the wild popu-lation hit a low of only 18 pairs in 1997,the recovery team decided it couldn’tsimply stand by and watch a species dis-appear without taking steps to save it (J. McCracken, pers.comm.).

Thus, in 1997 and 1998, a total of 43wild nestlings was collected to create acaptive breeding program with the goalof protecting the genetic diversity of thepopulation and, if possible, augmentingthe wild population by releasing captive-bred birds.

At the time, little was known abouthow to raise shrikes in captivity, and nocaptive breeding and release program hadbeen attempted at this scale for a migra-tory songbird. Not surprisingly, perhaps,the number of fledglings hatched in cap-tivity at McGill University and theToronto Zoo during the first five yearswas equaled by the number of deaths.

A switch in Ontario to field breedingin 2001 proved much more successful.This approach allowed captive shrikes toraise their young in large wood and wire

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mesh enclosures (Figure 4)sited in traditional shrikehabitat: cattle-grazed fieldsseparated by patches ofmixed forest and nativeshort grass land.

The fledglings pro-duced by field breeding areextremely fit (Figure 5).The young shrikes developstrong flight skills andpredator avoidance skills.They are also good hun -ters: as well as feeding onthe live crickets and meal-worms and thawed mice provided twice aday, they are frequently seen hawkinginsects in midair and catching frogs andsnakes that make their way into theenclosure.

Currently we have 24 field-breed-ing/re lease enclosures at two field sites insouthern Ontario: 10 in Dyer’s Bay on

the Bruce Peninsula,where shrikes have beenrecently extirpated; 14on the Carden Alvar,where a breeding popu-lation continues to existin the wild. Five addi-tional field-breeding en -closures are at an Inger-soll facility.

We also built a newoverwintering facility in2003 to improve the fit-ness of our captivebirds, which were suf-

fering from cramped winter quarters atthe Toronto Zoo. The new Ingersollfacility provides large indoor/outdoorflights for 47 birds, and freed up space atthe Zoo for more large enclosures withoutdoor access, reducing stress and im -proving muscle tone and body conditionfor the birds housed there.

Figure 5. Captive-bred young birds.Photo: Andrew Smart.

Figure 4. A field breeding enclosure.Photo: Pete Read.

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Releases: Achieving Precedent-Setting ResultsThe combination of field breeding andbetter winter accommodation greatlyincreased the number of fledglings pro-duced annually (Figure 6). In some yearsthe captive-bred pairs were more produc-tive than wild pairs, and double clutcheswere frequent. In 2001, the captive pop-ulation reached approximately 100 birds— large enough to begin releasing cap-tive-bred shrikes — and by 2006, pro-ductivity was high enough that we couldrelease approximately 100 fledglingseach season.

Because mortality rates are high formigratory songbirds, releasing thesekinds of numbers is essential if we are toboost the size of the wild population.Band results for juvenile Loggerhead

Shrikes in North America reveal returnrates between 0 and 4.7%, depending onthe pop ulation (Okines and McCracken2003).

To make the transition to the wild assmooth as possible, we use a soft-releasetechnique that starts with separatingfledglings from their parents between theages of 37 and 49 days and transferringthem to larger groups of mixed broods ina release enclosure. This mimics shrikebehaviour in the wild, where young fromdifferent nests travel together (Pruitt2000, Chabot et al. 2001a).

Once we have ensured the youngshrikes are successfully hunting the livemice we provide, they are ready to bereleased. Post-release, we provide supple-mental food until the birds are self-suffi-cient.

Figure 6. Productivity of field propagated pairs and number of fledglings produced between 2001 and 2008.

Year 2001 2002 2003 2004 2005 2006 2007 2008

120

100

80

60

40

20

0

Young released

Field breeding enclosures

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To maintain a captive population of120 adults, we keep back the most genet-ically important young each year. Using adetailed studbook that tracks kinshipcoefficients, inbreeding coefficients, andprevious breeding history, the best pair-ings are determined to maximize bothproductivity and genetic diversity. Todate, we succeeded in maintaining 97.1%of the genetic diversity of the wildfounders, well over the program’s goal of90% (Carnio 2007).

The real test of the success of our cap-tive breeding and release program is pro-ducing young that could survive in thewild, migrate, and return to breed. Ourbig breakthrough came in 2005 when acaptive-bred shrike was spotted on theCarden Alvar, where it subsequently bredwith wild a male and successfully fledgedfive young (Nichols and Steiner 2006).

Since then, we have seen more returnseach year (Figure 7). In the 2008 season,eight captive-bred birds were sighted inthe wild, including two released in 2006— the first time we have had release birds

return to breed in consecutive years. At6.4%, this year’s return rate was signifi-cantly higher than that of wild juveniles.In total, almost a quarter (22.2%) of wildpairs confirmed in Ontario this year con-tained a release bird.

Home on the Range: Habitat Stewardship EffortsOntario’s shrike habitat is shrinking;nearly all of the original grassland andsavannahs in the province have beenplowed under or paved over. At the sametime, much of the cattle pasture that pro-vided a substitute has been abandoned inrecent years. Meanwhile, increasingdevelopment is fragmenting much of theremaining habitat. Thus, habitat steward-ship was identified as an important com-ponent of the shrike recovery effort.

Early work focused on documentingcurrent and past nesting sites in Ontario,Quebec, and Manitoba (Smith 2001).Criteria for “suitable” and “restorable”habitat were developed, traditional corenesting areas were mapped in Ontario

and Quebec, andthe information wasrecorded in GIS-based mapping sys-tems (Smith 2001).

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Figure 7. Number of captive-bred releasebirds returning tobreeding grounds

* 2 birds returning in 2008 had beenreleased in 2006

Year 2005 2006 2007 2008

*

9

8

7

6

5

4

3

2

1

0

Numbe

r of b

irds

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One of the key challenges of shrikehabitat stewardship is the fact that muchof the habitat lies on private land.Thanks to personal contact, media cov-erage and public outreach (see “Commu-nity Outreach”), we have developed asolid base of landowner support for therecovery effort. In 2008, more than 80%of the landowners we contacted weresupportive and allowed staff on theirland for shrike monitoring and site eval-uation. Between 2001 and 2008, morethan 50 voluntary stewardship agree-ments and conservation agreements weresigned with landowners in core shrikeareas to protect, restore, or improveshrike habitat.

Under the federally funded Habitat

Stewardship Program, launched in2000/01, many landowners have receiv -ed advice and grants to make their prop-erty more attractive to shrikes. In manycases this involved installing fencing sothat abandoned pastures could be grazed(Figure 8) — a winning situation forboth farmers and shrikes.

Where needed, we removed en -croach ing cedars, thined overgrowngrasslands, planted nest/perch trees andshrubs, enhanced water sources for live-stock, and installed cattle oilers. In total,since 2001, we have worked with land -owners and volunteers to restore orimprove more than 4,600 hectares of keyshrike habitat (Table 1).

Figure 8. Fencing constructed to allow cows to pasture. Photo: Kyra Howes

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Shrike numbers are shrinking fasterthan would be expected based on habitatavailability on the summer range (Smith2001), implying other factors are causingthe population decline.However, it is clear thathabitat restoration work ismaking an impact. Today,more than half the wildpopulation is nesting onproperties that wereenhanced or restoredthrough the stewardshipprogram.

Wild Population: Mixed TrendsTo measure the success ofthe recovery effort, tracking wild num-bers is essential — no easy task with sucha small population, where overlookingonly a few pairs means missing a substan-tial percentage of the breeding population(Smith 2001). Since 1994, we have also

monitored productivity, mortality, andsurvivorship, although variations in thesampling effort in different years make itdifficult to compare figures.

Between 1999 and2006, more than 1,000adults and nestlingswere colour-banded,thus identifying eachbird, the year of band-ing, and whether cap-tive- or wild-bred birds.This gave us importantinformation on returnrates for juveniles andadults, immigrationand dispersal, demo-graphic make-up, and

population estimates of the wild shrikepopulation.

This year, nearly all the wild adults inOnt ario were captured for assessment,revealing that some returning birds hadlost their colour bands. Not only does this

make individualidentificationnearly impossi-ble in the field,it means thatcaptive returnrates in previousyears were likelyunderestimated.

2001 862

2002 350

2003 115

2004 680

2005 900

2006 207

2007 1575

TOTAL 4689

Table 1. Hectares of shrike habitatrestored or improved 2001-2007

Year Area (ha)

Figure 9. Numberof wild breedingpairs of EasternLoggerhead Shrikein Ontario, 1991-2008.

Know

n bree

ding

pair

s

60

50

40

30

20

10

0Year 1991 1993 1995 1997 1999 2001 2003 2005 2007

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While the level of the wild populationhas fluctuated considerably over the pastdecade, the last few years have seen anupswing (Figure 9). This year, 27 pairswere confirmed in Ontario — the high-est number since 2004, and significantlyhigher than the 18 pairs found in 1997.Other positive developments include thesighting of pairs in the historic breedingareas of Renfrew and Smiths Falls thisyear (three fledglings were also observedin Renfrew later in the season), and theoccupation of new territories in Carden.

Preliminary genetic, stable isotope,and banding data from across NorthAmerica, indicate that individuals fromother shrike populations join the Ont -ario population each year (Chabot andLougheed 2005), increasing genetic div -er sity and helping to maintain shrikenumbers here.

In turn, the Ontario populations mayfeed more southerly populations,although the extent of gene flow isunknown (A.A. Chabot pers. comm.).Further research is being done to deter-mine how important dispersal is for thesustainability of the Ontario population.

The Mystery of MigrationThe evidence that a considerable amountof breeding habitat is unoccupied(Chabot et al. 2001b, Jobin et al. 2005)and that wild pairs generally have highfledgling success (Chabot et al. 2001a)suggests the main causes of decline maylie outside Ontario. However, the migra-tory routes and location of the overwin-tering grounds for Ontario shrikes

remain unclear. To date, two of our cap-tive-bred shrikes have been sighted atLong Point during fall migration (J.McCracken and C. Wood pers. comm.),while one was sighted in Ohio in March2007 (P. Whan pers. comm.)— the firstwinter band recovery for this subspecies.

Preliminary results from stable iso-tope analysis of tail feathers from shrikesacross North America suggest that Ont -ario shrikes may not have a specific over-wintering ground. Instead, they likelyoverwinter throughout the winteringrange for this subspecies, as far south asFlorida (Chabot et al. 2006).

We hope to learn more about migra-tion patterns from a radio-tracking pro-gram where captive-bred shrikes are fit-ted with tiny radio-transmitters, with asignal radius of a few kilometres, thatallow researchers to track the birds by caror airplane. The transmitters, whichweigh only 1.4 grams, are attached to theback of the bird using a figure-8 leg-loopharness (Rappole and Tipton 1991),leaving visible only a fine, thread-likeantenna extending from the bird’s tail(Figure 10).

Trials were conducted on captiveshrikes in 2006/07 to test different har-ness designs (Steiner 2006). In a pilotstudy in 2007, 18 juvenile birds werereleased in Carden with live radio-trans-mitters, after first being tested with a“dummy” tag to ensure they had nophysical or behavioural effects on thebirds. This proved it was feasible to trackshrikes using a combination of groundand aerial telemetry.

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Our 2008 study, involving 20 radio-tagged birds showed that most stayednear the Carden site for several daysbefore dispersing. Individual shrikeswere tracked to Beaverton, Duclos Point(near the south end of Lake Simcoe), Vir-ginia Corners (about half-way to Toron-to) and near Hamilton. Through thetelemetry studies we learned that thepost-release survival rate for the captivebred/ released shrikes, prior to leavingCanada on mig ration, was between75%-77%.

This winter we areexploring the use of geolo-cators, which have justrecently been made lightenough to put on smallsongbirds.

Attached in the samemanner as radiotags, theycontinuously measure lightlevels. Because day lengthon a particular date varieswith latitude, and timingof sunrise or sunset varieswith longitude, this infor-mation will let us deter-mine the timing and routesof migration and locationof wintering grounds. Inorder to collect theselogged data, the birds willneed to be recaptured, butthe impressive return ratesseen with our captive juve-niles in the last few yearsmake this a real possibility.

Community OutreachBecause so much shrike habitat lies onprivate land, local landowner participa-tion is crucial to the success of the shrikerecovery effort. To build strong levels ofsupport and avoid the conflicts that canarise between property rights and theneeds of endangered species, we have puta strong emphasis on community out-reach over the past 15 years. Some of ourefforts have directly targeted landowners,including personal contact, a landowner

Figure 10. Shrike withradio-telemetery harness.Photo: Joe Crowley

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handbook, factsheets, and a series ofvideos providing an overview of shrikesand the recovery effort, habitat restora-tion, and the captive breeding and releaseprogram.

We have also created Recovery ActionGroups in core shrike areas to coordinatecommunity actions, working with land -owners and often bringing in volunteersto help with habitat stewardship andother activities. A newsletter keeps sup-porters updated on recovery efforts, whileannual landowner appreciation dinnersin Carden, Napanee, and Dyer’s Bayacknowledge the vital contribution oflandowners, volunteers, and donors toshrike recovery.

To heighten public awareness, we reg-ularly have displays at local events, whilemedia releases have garnered significantpress coverage. We have also created pub-lic service announcements for radio andTV, asking the public to report shrikesightings, while road signs warningmotorists to slow down have been erectedin nesting areas.

Most recently, we have helped tolaunch the Integrated Carden Conserva-tion Strategy (ICCS), a multi-stakeholderinitiative aimed to benefit a number ofspecies at risk, integrate recovery actionswith habitat conservation and steward-ship programs, and guide broader ecosys-tem-based land stewardship. Through aprocess that has earned kudos from par-ticipants, the ICCS has brought togethernaturalists, government representatives,farmers and ranchers, aggregate produc-ers, and private landowners to resolve

mistrust and conflict and develop a work-able conservation strategy for the CardenAlvar.

Summary: A Pioneering Model for RecoveryWhen the field breeding and release pro-gram was launched in 2001, it was envi-sioned as an experiment that would pro-duce new knowledge and insights (Smith2001). We have achieved that and more.While most captive breeding and releaseprograms typically take more than 10years to achieve their first successes, ourfirst captive-bred birds returned to breedjust 4 years after the first releases. Com-parisons with other captive breeding pro-grams for endangered birds also reveal ourprogram is extremely cost-effective — lessthan one-tenth the per-bird costs of theSan Clemente Loggerhead Shrike pro-gram in California, for example (Kleimanand Lynch 2008).

It takes a minimum of 15 years beforemost captive breeding and release pro-grams have impact on wild populations(Kleiman and Lynch 2008). While it isstill too early for our program to createsustained increases in wild populationlevels, it has generated many positiveeffects. We have restored grassland habitatthat will benefit other species in decline,including Bobolinks (Dolichonyx ory -zivorus), Upland Sandpipers (Bartramialongicauda), and Henslow’s Sparrows(Ammodramus henslowii). We have raisedawareness about endangered speciesthrough extensive public outreach. Most

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importantly, we have pioneered anapproach to captive breeding and releasethat generates fit, healthy young; a modelthat can be used by other recovery pro-grams for migratory passerines aroundthe world.

In May of 2007, WPC was told thatdue to severe budget cuts, EnvironmentCanada would not be able to fulfill itsfunding commitments under the conser-vation Agreement, and it would not berenewing the Agreement in March 2008.WPC managed to patch together enoughfunding from private donors and provin-cial and federal government sources tomaintain the captive population andother recovery activities in both 2007and 2008 . It is thanks to the contribu-tions from Boisset Family Estates (mak-ers of French Rabbit wines) that WPCwas able to launch the successful 2008field season, since federal and provincialfunding commitments were made onlyvery late into the field season.

However, with no ConservationAgree ment in place, and no multi-yearcommitments from either the federal orprovincial governments, funding for therecovery effort will again be uncertainand piecemeal, making it difficult to planor work in any strategic fashion. Despitethe success of the program, and themoney and time spent on recovery, thewhole program faced the prospect ofbeing shut down when funding was cutin 2007/2008. That is still a possibility if funding cannot be found in the com-ing year.

AcknowledgementsEnvironment Canada, through the HabitatStewardship Program and grants and contri-butions, has been the lead funder of the shrikerecovery efforts. In 2007 and 2008 theOntario Species at Risk Stewardship Fundalso provided significant funding support.Boisset Family Estates is the single largest private sector supporter of recovery effort. In addition to Environment Canada and theprovinces of Ontario, Manitoba and Quebec,we would like to acknowledge our otherrecovery partners: Avian Science and Conser-vation Centre of McGill University, BirdStudies Canada, Canadian Cattlemen’s Asso-ciation, Canadian Association of Zoos andAquariums, Canadian Cooperative WildlifeHealth Centre, Toronto Zoo, Queen’s Uni-versity, and many landowners. A big thankyou as well to the many landowners, volun-teers, interns, researchers, and field staff whohave contributed to the recovery effort overthe years. We also thank free-lance writer,Julie Staffer, for pulling this article together.

Further details of the recovery programare available from Wildlife PreservationCanada at www.wildlifepreservation.ca or 1-800-956-6608, and contributions to therecovery program would be welcomed.

Literature CitedButcher G.S. and D.K. Niven. 2007. Combining data from the Christmas BirdCount and the Breeding Bird Survey to determine the continental status and trends of North American birds. Audubon Societytechnical report.

Carnio, J. 2007. Eastern Loggerhead Shrikestudbook report 2006/2007. Unpublishedreport to Eastern Loggerhead Shrike RecoveryTeam, Ken Tuininga (Canadian Wildlife Serv-ice – Ontario),Chair. Toronto, Ontario. 7 pp.

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Chabot, A.A. and S.C. Lougheed. 2005. His-toric and present day apportionment of geneticdiversity in the eastern subspecies of LoggerheadShrike (Lanius ludovicianus migrans): interde-partmental recovery fund final report 2005.Unpublished report for Canadian Wildlife Serv-ice, Ontario Region. Kingston, Ontario. 37 pp.

Chabot, A.A., D.M. Bird and R.D. Titman.2001a. Breeding biology and nest success ofLoggerhead Shrikes in Ontario. Wilson Bulletin113:285-289.

Chabot, A.A., R.D. Titman and D.M. Bird.2001b. Habitat use by Loggerhead Shrikes inOntario and Quebec. Canadian Journal of Zool-ogy 79:916-925.

Chabot, A., K. Hobson and S.C. Lougheed.2006. Wintering movements of LoggerheadShrikes from Ontario: results from stable isotope analysis of feather samples 2001-2005.Unpublished report prepared for the Endanger -ed Species Research Fund. Kingston, Ontario.

Environment Canada. 2006. Recovery strategyfor the Loggerhead Shrike, migrans subspecies(Lanius ludovicianus migrans), in Canada [proposed]. Species at Risk Act Recovery Strategy Series. Environment Canada, Ottawa. vi + 25 pp.

Jobin, B., M. Grenier and P. Laporte. 2005.Using satellite imagery to assess breeding habitatavailability of the endangered Loggerhead Shrikein Quebec. Biodiversity and Conservation14:81-95.

Johns, B., E. Tefler, M. Cadman, D. Bird,R. Bjorge, K. DeSmet, W. Harris, D. Hjertas,P. Laporte and R. Pittaway. 1994. Nationalrecovery plan for the Loggerhead Shrike. Recov-ery of Nationally Endangered Wildlife Commit-tee Report number 7, Ottawa, Ontario. 32pp.

Kleiman, D.G. and C. Lynch. 2008. Finalreport: Results and recommendations for thecaptive breeding/release program for the easternloggerhead shrike. Zoo-Logic, Limited LiabilityCompany. Chevy Chase, Maryland, U.S.A.

Miller, A.H. 1931. Systematic revision and natural history of the American shrikes (Lanius).University of California Publications in Zoolo-gy. 38:11-242.

Nichols, R. and J. Steiner. 2006. Eastern Log-gerhead Shrike in Ontario end of season report2005: field monitoring and experimental captive breeding and release programs. Unpub-lished report to Canadian Wildlife Service,Ontario Region. Guelph, Ontario. 162 pp.

Okines, D. and J. McCracken. 2003. Logger-head Shrike banding in Ontario: report on the2003 field season. Unpublished report to Cana-dian Wildlife Service and Wildlife PreservationTrust Canada. Port Rowan, Ontario.

Pruitt, L. 2000. Loggerhead Shrike statusassessment. U.S. Fish and Wildlife Service.Bloomington, Indiana. 169 pp.

Rappole J.H. and A.R. Tipton. 1991. New har-ness design for attachment of radio transmittersto small passerines. Journal of Field Ornithology62:335-337.

Smith, M.C. 2001. Eastern Loggerhead Shrikeprogram review 1994 to March 31, 2000. Environment Canada, Canadian Wildlife Service. Acton, Ontario. 54 pp.

Steiner, J. 2006. A trial of “dummy” radiotrans-mitters on juvenile captive-born Eastern Loggerhead Shrike. Wildlife Preservation Canada, Guelph, Ontario. 13 pp.

Yosef, R. 1996. Loggerhead Shrike (Laniusludo vicianus). In The Birds of North America,No. 231 (A. Poole and F. Gill, eds.). The Acade-my of Natural Sciences, Philadelphia, and TheAmer ican Ornithologists' Union, Washington,D.C.

Elaine Williams, Wildlife Preservation Canada,R.R. #5, 5420 Hwy. 6 North, Guelph, OntarioN1H 6J2.

Jessica Steiner, Wildlife Preservation Canada,R.R. #5, 5420 Hwy. 6 North, Guelph, OntarioN1H 6J2.

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