Download - 1999 Exxon Valdez Oil Spill Injured Resources & Services Update

8/9/2019 1999 Exxon Valdez Oil Spill Injured Resources & Services Update

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Exxon Valdez Oil Spill Trustee Council

Ex x o n Va l d e z Oil Spil l Res t o r at io n Pl anUpdate on Injured Resources and Services

March 1999

Ex x o n Va l d ez Oil Spil l Tr u st ee Co u n c il645 G Street, Suite 401, Anchorage, AK 99501

907-278-8012 800-478-7745 (in Alaska) 800-283-7745 (outside Alaskas)


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UPDATE ONINJUREDRESOURCES ANDSERVICESINTRODUCTION

History and Purposes of the ListIn N ovember 1994, the Trustee Cou ncil adopted an offi

cial list of Injured Resources and Services Injured by th e Spillas part of the Restoration Plan . This list serves three mainpurposes:

1. It is representative of injuries caused by th e oil spill andcleanu p efforts and helps the Trustees and the pu blic track the statu s of imp ortant fish, wildlife, and other resourcesand services. The fish and wildlife on this list are thou ghtto have suffered population-level or sublethal injuries,but it d oes not includ e every species or resource that suffered some degree of injury. For example, carcasses of about 90 different species of oiled birds were recoveredin 1989, but only 10 species of birds are on the list of in

jured species.

2. It helps g uid e priorities for imp lementation of the Resto-ration Plan . This was especially impor tant in 1994 wh enthe p lan w as first adop ted, bu t the list still serves to highlight resources that are in need of attention. For examp le,wh at add itional work can be und ertaken to clarify thestatus of recovery-unknown resources, or what can bedone, if anything, to help move resources from not recovering to recovering or from recovering to recovered?

3. Finally, taken as a w hole, the list of injured resources help sthe Trustees and the p ublic track recovery of the overallecosystem and the functions and human services that itprovides. For examp le, neither the ecosystem nor the service of commercia l f i shing can be judged to haverecovered from the effects of the oil spill until keystoneresources, such as Pacific herring, are themselves fullyrecovered.

Chap ter 4 of the Restoration Plan indicates that the InjuredResources and Services list will be reviewed periodically

and up da ted to reflect wh at is learned from scientific studies and other sou rces of informa tion, such as from trad itionaland local know ledge. Each time the list is reviewed , aresources prog ress or lack of progress tow ard recovery isevaluated with reference to a recovery objective that is asconcrete and measu rable as possible. Sometimes the recovery objectives themselves are chan ged t o reflect new insigh ts

about the na ture of the injury and the best ways to evaluaterecovery status. The table on page 3 includes brief descriptions of what each recovery category means.

The Injured Resources and Services list w as first u pd atedin Septem ber 1996. A t that time, for examp le, the bald eaglewas u pgr aded from recovering to recovered. In 1999, 10years after the oil spill, several more changes have beenmad e. The river otter is now considered to be recovered,and five resourcesblack oystercatcher, clams, marbledmu rrelet, Pacific herring, sea otterare up grad ed to recovering. One resource, comm on loon, is moved from recoveryun know n to not recovering. Five resources remain as re

covery un know n. Four hum an services are classified asrecovering.

The Injured Resources and Services list can b e up datedat any time that new information becomes available. It islikely, how ever, that the n ext evaluation of chan ges in recovery status for all injured resources and lost or redu cedservices will be in 2001, 10 years after the 1991 settlementbetween the governments and Exxon and initiation of therestoration program.

Ecosystem Perspective and RecoveryThe List of Injured Resources consists mainly of single

species and resources, but, as noted above, it provides a basis for evalua ting the recovery of the overall ecosystem, itsfunctions, and th e services that it prov ides to peop le. Infact, through the Restoration Plan , the Trustee Counciladop ted an ecological app roach to restoration, and the studies and projects it sponsor s hav e been increasingly ecologicalin character.

Page 35 of the Restoration Plan defines ecosystem recovery as follows:

Full ecological recovery will have beenachieved when the population of flora andfauna are again p resent at former or p respill

abundances, healthy and productive, andthere is a full complement of age classes atthe level that wou ld have been p resent hadthe spill not occurred. A recovered ecosystem p rovides the same functions and servicesas would have been provided had the spillnot occurred.

U PDATE ON I NJURED R ESOURCES AND S ERVICES March 1999

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H UMAN SERVICESHuman services that depend on natural resources were also injured by the oil spill.These services are each considered to be recovering until the resources on which they depend are fully recovered.

Recreation & tourismCommercial fishing

Passive usesSubsistence

Cutthroat troutDesignated

RECOVERYU NKNOWN

Bald eagleRiver otter

Pacific herringPink salmonSea otterSediments

Sockeye salmonSubtidal communities

Common loonCormorants (3 spp.)

Harbor sealHarlequin duck

Killer whale (AB pod)Pigeon guillemot

Archaeological resourcesBlack oystercatcher

ClamsCommon murres

Intertidal communitiesMarbled murrelets

Mussels

Species are showing little or no clear improvement since spill injuries occurred.

Limited data on life history or extent of injury; current research inconclusive or not complete.

Substantive progress is being made toward recovery objective. The amount of progress and time needed to achieve recovery vary depending on the resource.

Recovery objectives have been met

Wilderness Areas

Rockfish

Resources in boldface have eachmoved on this Recovery Lineduring the most recent update(February 9, 1999)

RECOVERING RECOVERED

N OT RECOVERING

Photo by Roy Corral

Resources and Services Injured by

Dolly VardenKittlitzs murrelet

Using this d efinition, the coastal and m arine ecosystemin the oil-spill region has not recovered from the effects of the oil spill. Keystone sp ecies, such as Pacific herr ing andharbor seals, have not fully recovered, nor h as the composition of biological comm un ities, such as in intertid al habitats.Although full ecological recovery has not been achieved,

the spill-area ecosystem is still largely intact and functioning and on the way to recovery 10 years after the ExxonValdez .

It also is importan t to und erstand th at ecosystems are dynamic and w ould h ave changed even in the absence of theoil spill. Baseline d ata d escribing fish and wildlife pop ulations, to say nothing of complex intertidal and subtidal

commu nities, were generally poor. For this reason, it wasand is difficult to evaluate injury to individual resourcesand the ecosystem in general, and an inability to docum entinjury becau se of poor baseline data d oes not mean th at in

jury d oes not exist. It also is impor tant to note that as thetime since the oil spill grows longer, it is more and more

difficult to separ ate wh at ma y be lingering effects of the sp illfrom changes that are natu ral or caused by factors un relatedto the oil spill. In fact, wha t w e see is often an interactionbetween oil effects and natu ral changes, such as the effectsof the 1998 El Nio on common murres in the Barren Islands.


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Co n t en t sIn j u r e d R es o u r c e s

Ar ch aeo l og ical Resou r ces . . . . . . . . . . . .. . . . . . . . . . .. . . . . . . . . . . ..Bal d Eagl es . . . . . . . . . . .. . . . . . . . . . . .. . . . . . . . . . .. . . . . . . . . . .. . . . . . . . . . . .. . .Bl a ck Oyst er cat ch er s . . . . .. . . . . . . . . . .. . . . . . . . . . . .. . . . . . . . . . .. . . . .Common Lo on s . . . . . . . . . . .. . . . . . . . . . . .. . . . . . . . . . .. . . . . . . . . . . .. . . . . . . . .Cl ams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Common Mu r r es . . . . . . . . . . .. . . . . . . . . . . .. . . . . . . . . . .. . . . . . . . . . . .. . . . . . .Cor mor ant s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Cut t hr oa t Tr ou t . . . . . . . . . . . .. . . . . . . . . . .. . . . . . . . . . . .. . . . . . . . . . .. . . . .Design at ed Wil de r ness Ar eas . . . . . . . . . .. . . . . . . . . . . .. . . . . . . . . . .Dol l y Var den . . . . . . . . . . . .. . . . . . . . . . . .. . . . . . . . . . .. . . . . . . . . . .. . . . . . . . . . .Har l eq uin Duc ks . . . . . . . . . . . .. . . . . . . . . . .. . . . . . . . . . . .. . . . . . . . . . .. . . . .Har bo r Seal s . . . . .. . . . . . . . . . . .. . . . . . . . . . .. . . . . . . . . . . .. . . . . . . . . . .. . . . . . .Int er t idal co mmun it ies . . . . . . . . . . . . .. . . . . . . . . . .. . . . . . . . . . . .. . . . . .Kit t l i t zs M u r r el et s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Kil l er Wh al es . . . . . . . . . . .. . . . . . . . . . . .. . . . . . . . . . .. . . . . . . . . . . .. . . . . . . . .Mar bl ed Mu r r e l e t s . . . . . . . . . .. . . . . . . . . . . .. . . . . . . . . . .. . . . . . . . . . . .. .Mu ssel s . . . . . . . . . .. . . . . . . . . . . .. . . . . . . . . . .. . . . . . . . . . .. . . . . . . . . . . .. . . . . . . . . .Pacif ic Her r in g . . . . . .. . . . . . . . . . .. . . . . . . . . . . .. . . . . . . . . . .. . . . . . . . . . . .. .Pigeo n Guil l e mot s . . . . . . . . . . . .. . . . . . . . . . .. . . . . . . . . . . .. . . . . . . . . . .. . .Pink Sal mon . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . .. . . . . . . . . . .. . . . . . . . . . . .. . . .Riv er Ot t er s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Roc kf ish . . . . . . . . . .. . . . . . . . . . . .. . . . . . . . . . .. . . . . . . . . . . .. . . . . . . . . . .. . . . . . . .Sea Ot t er s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Sedimen t s . . . . . . . . . .. . . . . . . . . . . .. . . . . . . . . . .. . . . . . . . . . . .. . . . . . . . . . .. . . . . . .Soc keye Sal mon . . . . . . . . . . .. . . . . . . . . . . .. . . . . . . . . . .. . . . . . . . . . . .. . . . . . . .Subt idal Commun it ies . . . . . . . . . . . . . . . .. . . . . . . . . . . .. . . . . . . . . . .. . . . .

H u ma n S e r v i c e s

Commer cial Fishin g .. . . . . . . . . . .. . . . . . . . . . . .. . . . . . . . . . .. . . . . . . . . . . ..Passive Uses . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . .. . . . . . . . . . .. . . . . . . . . . . .. . . . .Recr eat ion an d To ur ism . . . . . . . . . . . . . . . . .. . . . . . . . . . .. . . . . . . . . . . ..Subsis t en ce . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . .. . . . . . . . . . .. . . . . . . . . . . .. . . . .

Photo by Roy Corral


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A RCHAEOLOGICAL R ESOURCES

Injury and RecoveryThe oil-spill area is believed to contain

more than 3,000 sites of archaeological andhistorical significance. Twenty-four archaeological sites on public lands are knownto have been adversely affected by cleanupactivities or looting and vandalism linkedto the oil spill. Additional sites on both public and private lands were probably injured,but damage assessment studies were limitedto public land and not designed to identifyall such sites.

Documented injuries include theft of surface artifacts, masking of subtle cluesused to identify and classify sites, violationof ancient burial sites, and destruction of

evidence in layered sediments. In addition,vegetation was disturbed, which exposedsites to accelerated erosion. The effect of oilon soil chemistry and organic remains mayreduce or eliminate the utility of radiocarbon dating in some sites.

Assessments of 14 sites in 1993 suggested that most of the archaeological vandalism that can be linked to the spill occurredearly in 1989, before adequate constraintswere put into place over the activities of oilspill clean-up personnel. Most vandalismtook the form of prospecting for high yield

sites. Once these problems were recognized,protective measures were implemented andsuccessfully limited additional injury. In1993, only two of the 14 sites visited showed

BBBBB A L DA L DA L DA L DA L D EEEEE AGLESAGLESAGLESAGLESAGLES

signs of continued vandalism. In 1996, therewas evidence of vandalism at five sites, butonly at one site in 1997. Natural erosion isthe major agent of degradation at the sites,and the erosion draws the attention of looters to the exposed artifacts. Nine years after the oil spill it is difficult to attribute therecent cases of vandalism to discovery of these sites at the time of the oil spill.

Oil was visible in the intertidal zonesof two of the 14 sites monitored in 1993,and hydrocarbon analysis has shown that theoil at one of the sites was from the ExxonValdez spill. Hydrocarbon concentrations atthe second site were not sufficient to permitidentification of the source or sources of the

oil. The presence of oil in sediment samplestaken from four sites in 1995 did not appearto have been the result of re-oiling by ExxonValdez oil.

In 1993, the Trustee Council providedpart of the construction costs for the AlutiiqArchaeological Repository in Kodiak. Thisfacility now houses Kodiak-area artifacts thatwere collected during the time of spill response. Artifacts recovered from injured sitesin lower Cook Inlet and Prince William Soundcurrently are stored at the University of Alaska Fairbanks or elsewhere. In 1999,

however, the Trustee Council approved funding for an archaeological repository and local display facilities for artifacts from PrinceWilliam Sound and lower Cook Inlet.

Two sites in Prince William Sound wereso badly damaged by oiling and erosion thatthey were partly documented, excavated,and stabilized by professional archaeologistsin 1994-1997. It appears that the two siteswere intermittently occupied for periods of 2,000 and 3,000 years. Most of the culturaldeposits are prehistoric in nature.

Starting in 1996, the Trustee Councilfunded a project to involve local residentsin monitoring and protecting vulnerable sitesin the Kenai, Homer, Seldovia, Kodiak, andChignik areas. This project was based onthe premise that successful long-term stewardship depends on community support andinvolvement. A report on this project is due

in 1999. Based on the apparently low rateof spill-related vandalism and progress inthe preservation of artificats and scientific data on archaeological sites and artifacts, archaeological resources are considered to be recovering.Recovery Objective

Archaeological resources are nonrenewable: they cannot recover in the samesense as biological resources. Archaeological resources will be considered to have recovered when spill-related injury ends, looting and vandalism are at or below prespill

levels, and the artifacts and scientific dataremaining in vandalized sites are preserved(e.g., through excavation, site stabilization,or other forms of documentation).

Injury and RecoveryThe bald eagle is an abundant resident

of marine and riverine shoreline throughoutthe oil-spill area. Following the oil spill, atotal of 151 eagle carcasses was recovered

from the spill area. Prince William Soundprovides year-round and seasonal habitat forabout 6,000 bald eagles, and within the soundit is estimated that about 250 bald eagles diedas a result of the spill. There were no estimates of mortality outside the sound, butthere were deaths throughout the spill area.

In addition to direct mortalities, productivity was reduced in oiled areas of PrinceWilliam Sound in 1989. Productivity wasback to normal in 1990 and 1991, and anaerial survey of adults in 1995 indicated that

the population had returned to or exceededits prespill level in the sound.In September 1996, the Trustee

Council classified the bald eagle as fullyrecovered from the effects of the oil spill.No additional work has been carried out specifically to assess the status of the bald eagle.

However, the bald eagle has benefited enormously from the habitat protection program,including the acquisition of more than 1,200miles of marine shoreline and 280 anadromous fish streams.

Recovery ObjectiveBald eagles will have recovered when

their population and productivity have returned to prespill levels.


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BBBBB LACKLACKLACKLACKLACK OOOOO YSTERCATCHERSYSTERCATCHERSYSTERCATCHERSYSTERCATCHERSYSTERCATCHERS

Injury and RecoveryBlack oystercatchers spend their entire

lives in or near intertidal habitats and are highlyvulnerable to oil pollution. It is estimated that1,500-2,000 oystercatchers breed in south-cen-tral Alaska. Only nine carcasses of adult oystercatchers were recovered following the spill,but the actual number of mortalities may havebeen considerably higher.

In addition to direct mortalities, breedingactivities were disrupted by the oil and cleanupactivities. When comparing 1989 with 1991,significantly fewer pairs occupied and maintained nests on oiled Green Island, while during the same two years the number of pairsand nests remained similar on unoiledMontague Island. Nest success on Green Island was significantly lower in 1989 than in1991, but Green Island nest success in 1989was not lower than on Montague Island. In1989, chicks disappeared from nests at a significantly greater rate on Green Island thanfrom nests on Montague Island. Disturbanceassociated with cleanup operations also reduced productivity on Green Island in 1990.In general, the overt effects of the spill andcleanup had dissipated by 1991, and in thatyear productivity on Green Island exceededthat on Montague Island.

From 1991-1993, the Trustee Councilsponsored a study to determine if there wereany persistent effects of the spill on breedingsuccess and feeding ecology of black oyster

catchers on Knight Island. Adult oystercatchers foraged in oiled mussel beds, but also obtained invertebrate prey at unoiled sites. Aslate as 1993, there was direct evidence of hydrocarbon exposure from fecal samples of chicks raised on persistently oiled shorelines,but areas of contamination were patchily distributed and relatively few adults and youngwere exposed. In 1989, chicks raised on oiledshorelines gained weight more slowly thanchicks reared on unoiled shores, but the slowerweight gain was not manifested in reducedfledging success. Surveys from 1991-1993 indicated that the population inhabitating KnightIsland was not increasing. Hydrocarbon exposure has not been tested since 1993.

Productivity and survival of black oystercatchers in Prince William Sound were notmonitored from 1993 through 1997. Boat-based surveys of marine birds in the sound didnot indicate recovery in numbers of oystercatchers in oiled areas through 1998, but thesesurveys were not specifically designed tomonitor oystercatchers.

In 1998 the Trustee Council sponsored astudy to reassess the status of this species inPrince William Sound. Only preliminary results are available, but these data indicate thatoystercatchers have fully reoccupied and are

nesting at oiled sites in the sound. The breeding phenology of nesting birds was relativelysynchronous in oiled and unoiled areas, andno oil-related differences in clutch size, egg

volume, or chick growth rates were detected.A high rate of nest failures on Green Islandprobably can be attributed to predation, not lingering effects of oil. Given general agreement between these new results and thoseof the earlier work, which indicated that theeffects of the spill had largely dissipated by1991, recovery of black oystercatchersclearly is underway.

Black oystercatchers nest on rockybeaches and have benefited enormously fromthe habitat protection program, including theacquisition of more than 1,200 miles of marine shoreline. In addition, introduced foxeswere eliminated from two of the ShumaginIslands (Simeonof and Chernabura) in thesouthwestern part of the spill area. Black oystercatchers were present in low densities onboth islands, and in higher densities on nearbyfox-free islands. Although the nesting birdshave not been surveyed since 1995, when thelast of the foxes was removed, the eliminationof the introduced predators should increasepopulations of nesting oystercatchers.Recovery Objective

Black oystercatchers will have recoveredwhen the population returns to prespill levelsand reproduction is within normal bounds. Anincreasing population trend and comparable

hatching success and growth rates of chicks inoiled and unoiled areas, after taking into account geographic differences, will indicate thatrecovery is underway.

CCCCC OMMONOMMONOMMONOMMONOMMON LLLLL OONSOONSOONSOONSOONS

Injury and RecoveryCarcasses of 395 loons of four species were

recovered following the spill, including at least216 common loons. Current population sizesin the spill area are not known for any of thesespecies. Common loons in the spill area may

number only a few thousand, including onlyhundreds in Prince William Sound. Commonloons injured by the spill probably included amixture of wintering and migrating birds. Thespecific breeding areas used by the loons affected by the spill are not known.

Boat-based surveys of marine birds in

Prince William Sound give at least some insight into the recovery status of the loons affected by the oil spill. These surveys indicated that the oil spill had a negative effecton numbers of loons (all species combined)in the oiled parts of the sound in 1991. Basedon the surveys carried out through 1998, thereis no indication of recovery. Further, a comparison of July 1984 versus July 1990-98survey data suggests that loons (all species)show a pattern of increasing densities inunoiled parts of the sound and essentiallystable densities in oiled parts of the sound.

This disparity is consistent with possible lack of recovery from an oil-spill effect. Thus,the common loon is considered to have notrecovered from the effects of the spill. Noadditional information on the status of common loons is available.

Recovery ObjectiveCommon loons will have recovered when

their population returns to prespill levels in theoil- spill area. An increasing population trendin Prince William Sound will indicate that recovery is underway.


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CCCCC LAMSLAMSLAMSLAMSLAMS

Injury and RecoveryThe magnitude of immediate impacts

on clam populations varied with the speciesof clam, degree of oiling, and location. Data

from the lower intertidal zone on shelteredbeaches suggested that littleneck clams and,to a lesser extent, butter clams were killedand suffered slower growth rates as a resultof the oil spill and cleanup activities.

Since the original damage assessmentwork on clams in 1989 and 1990, the TrusteeCouncil has not sponsored additional studies focused specifically on clam injury andrecovery. Some insights are available fromprojects carried out by the NOAA Hazardous Materials Division and others on intertidal and subtidal communities in relationto oil and shoreline treatments. In general,these studies indicate that intertidal faunadwelling in soft sediments, including various clam species, had rebounded withinone-three years after 1989 on oiled-but-un-

treated shorelines. On these shorelines,abundances or trends in abundance of intertidal fauna were parallel or similar to thoseat unoiled, untreated sites. One study docu

mented that concentrations of hydrocarbonsin littleneck clam tissues at oiled and unoiledsites were not significantly different by1993. These results indicate that recoveryis underway.

Clearly, however, full recovery has notbeen achieved, especially on shorelines thatwere oiled and treated by hot-water washes.For example, one study found that densitiesof littleneck and butter clams were depressedthrough 1996 on oiled, treated mixed-sedi-mentary shores where fine sediments hadbeen washed downslope during pressured

water treatments. Comparing oiled studysites on Knight Island with unoiled sites onMontague Island, researchers in theNearshore Vertebrate Predator project founda full range of size classes of clams at the

oiled sites, as well as more large clams.However, oiled sites also had fewer juvenile clams and lower numbers of severalspecies. Based on all of the evidence sum

marized above, clams are recovering, butare not yet fully recovered from the effects of the oil spill.

In communities on the Kenai Peninsula,Kodiak Island, the Alaska Peninsula and inPrince William Sound there are lingeringconcerns about the effects of the oil spill onclams. The Trustee Council sponsored aproject to help restore subsistence uses of clams (see subsistence).

Recovery objectiveClams will have recovered when popu

lations and productivity have returned tolevels that would have prevailed in the absence of the oil spill, based on comparisonsof oiled and unoiled sites.

CCCCC OMMONOMMONOMMONOMMONOMMON MMMMM URRESURRESURRESURRESURRES

Injury and RecoveryAbout 30,000 carcasses of oiled birds

were picked up in the first four months following the oil spill, and 74 percent of themwere common and thick-billed murres(mostly common murres). Many moremurres probably died than actually were recovered. Based on surveys of index breeding colonies at such locations as the BarrenIslands, Chiswell Islands, Triplet Islands,Puale Bay, and Ugiaushak Island, the spill-area population may have declined by about40 percent following the spill. In additionto direct losses of murres, there is evidencethat the timing of reproduction was disruptedand productivity reduced. Interpretation of

the effects of the spill, however, is complicated by incomplete prespill data and by indications that populations at some colonieswere in decline before the oil spill.

Postspill monitoring at the breeding colonies in the Barren Islands indicated that reproductive success was again within normal

bounds by 1993, and it has stayed within thesebounds each breeding season since then. During the period 1993-1997, the murres nested

progressively earlier by 2-5 days each year,suggesting that the age and experience of nesting birds was increasing, as might be expectedafter a mass mortality event. By 1997, numbers of murres at the Barren Islands had increased, probably because 3-and 4-year oldnonbreeding subadult birds that were hatchedthere in 1993 and 1994 were returning to theirnatal nesting colony. This information suggests that recovery is well underway, although the strong 1998 El Nio event apparently disrupted timing and synchronyof nesting at the Barren and Chiswell islands

and may, to some extent, have affected reproductive success. The Barren Islands colonies will be surveyed again in 1999.

Although Prince William Sound doesnot have a large summer population of murres, boat-based surveys of marine birdsbefore and after the oil spill indicated a nega

tive effect on numbers in the sound. Surveys carried out through 1998 have notshown any increase in murres since the spill.

The Alaska Predator Ecosystem Experiment (APEX project), funded by the TrusteeCouncil, is investigating the linkage betweenmurre populations and changes in the abundance of forage fish, such as Pacific herring,sand lance, and capelin. Historical trawl dataanalyzed as part of this project supported adecision by the North Pacific Fishery Management Council to limit bycatch of foragefish in commercial fisheries and to precludethe startup of fisheries targeting forage fish(not including herring).Recovery Objective

Common murres will have recoveredwhen populations at index colonies havereturned to prespill levels and when productivity is sustained within normal bounds.Increasing population trends at index colonies will be a further indication that recovery is underway.


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CCCCC ORMORANTSORMORANTSORMORANTSORMORANTSORMORANTS

Injury and RecoveryCormorants are large fish-eating birds

that spend much of their time on the wateror perched on rocks near the water. Threespecies typically are found within the oil-spill area.

Carcasses of 838 cormorants were recovered following the oil spill, including 418pelagic, 161 red-faced, 38 double-crested, and221 unidentified cormorants. Many morecormorants probably died as a result of thespill, but their carcasses were not found.

No regional population estimates areavailable for any of the cormorant speciesfound in the oil-spill area. In 1996, the U.S.Fish and Wildlife Service Alaska Seabird

CCCCC UTTHROATUTTHROATUTTHROATUTTHROATUTTHROAT TTTTT R O U TROUTR O U TROUTR O U T

Injury and RecoveryPrince William Sound is at the northwest

ern limit of the range of cutthroat trout. Localcutthroat trout populations are believed to besmall, and the fish have small home rangesand are geographically isolated. Cutthroattrout, therefore, are highly vulnerable to exploitation, habitat alteration, or pollution.

Following the oil spill, cutthroat trout ina small number of oiled index streams inPrince William Sound grew more slowly thanin unoiled streams. The apparent differencein growth rates persisted through 1991. Itwas hypothesized that the slower rate of growth in oiled streams was the result of reduced food supplies or exposure to oil, andthere was concern that reduced growth rateswould result in reduced survival.

Preliminary data from a Trustee Coun-cil-sponsored study of resident and anadromous forms of cutthroat trout in Prince William Sound suggest that there is significant

genetic variation among trout from different locations across the sound. These dataare consistent with the idea that cutthroatpopulations are small and isolated. Thiswork is being completed in FY 1999 andshould make possible insights into such issues as growth rates with respect to geo

oiled portion of Prince William Soundbased on pre- and postspill boat surveys inJuly 1972-73 compared to 1989-91. Morerecent surveys (through 1998) have not

shown an increasing population trendsince the oil spill, and for that reasonthese species are considered to be notrecovered.

Recovery ObjectivePelagic, red-faced, and double-crested

cormorants will have recovered when theirpopulations return to prespill levels in theoil-spill area. An increasing population trendin Prince William Sound will indicate thatrecovery is underway.

The TrusteeCouncil sponsored inventories of streamsin and around PrinceWilliam Sound toidentify cutthroattrout habitat and thepresence or absenceof this species. Information from these inventories has beenadded to the AlaskaDepartment of Fishand Games Anadro-

Photo by Roy Corral mous Waters Catalog,and this step brings to

bear additional legal protection under statelaw in regard to actions affecting thesestreams. Additional habitat for cutthroat trouthas been protected from among the more than280 anadromous fish streams that have beenacquired through the Trustee Councils habitat protection program.

Recovery ObjectiveCutthroat trout will have recovered

when growth rates within oiled areas aresimilar to those for unoiled areas, after taking into account geographic differences.

Colony Catalog, however, listed counts of 7,161 pelagic cormorants, 8,967 red-facedcormorants, and 1,558 double-crested cormorants in the oil-spill area. These are

direct counts at colonies, not overall population estimates, but they suggest thatpopulation sizes are small. In this context, it appears that injury to all three cormorant species was significant.

Counts on the outer Kenai Peninsulacoast suggested that the direct mortality of cormorants due to oil resulted in fewer birdsin this area in 1989 compared to 1986. Inaddition, there were statistically-significantdeclines in the estimated numbers of cormorants (all three species combined) in the

Cutthroat Trout

graphic variation. Pending this additionalwork, the recovery status of the cutthroattrout remains unknown.

Cutthroat trout have benefited from several other projects sponsored by the TrusteeCouncil. In 1991-93, in response to the early

evidence of injury to cutthroat trout, sportharvests were temporarily restricted in PrinceWilliam Sound. In 1994, out of concern aboutthe long-term conservation status of this species, the Alaska Board of Fisheries permanently closed sport harvests during the April15-June 15 spawning season in the sound.


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DDDDD ESIGNATEDESIGNATEDESIGNATEDESIGNATEDESIGNATED WWWWW ILDERNESSILDERNESSILDERNESSILDERNESSILDERNESS AAAAA REASREASREASREASREAS

Injury and RecoveryThe oil spill delivered oil in varying

quantities to the waters and tidelands adjoining eight areas designated as wilderness ar

eas and wilderness study areas by Congressor the Alaska State Legislature. Oil also wasdeposited above the mean high-tide line atthese locations. During the intense clean-upseasons of 1989 and 1990, thousands of workers and hundreds of pieces of equipment were at work in the spill zone. Thisactivity was an unprecedented imposition of people, noise, and activity on the areas undeveloped and normally sparsely occupiedlandscape. Although activity levels on thesewilderness shores have probably returned tonormal, at some locations there is still residual oil.

Among the affected areas were designated wilderness in the Katmai NationalPark, wilderness study areas in the ChugachNational Forest and Kenai Fjords NationalPark, and Kachemak Bay Wilderness State

DDDDD O L LYO L LYO L LYO L LYO L LY VVVVV ARDENARDENARDENARDENARDEN

Injury and RecoveryDolly Varden are widely distributed in

the spill area. In spring, anadromous formsof Dolly Varden migrate to the sea from thelakes and rivers where they spend the winter. Summers are spent feeding in nearshoremarine waters. Thus, some Dolly Varden inPrince William Sound and perhaps at otherlocations were exposed to Exxon Valdez oilin 1989 and possibly beyond. In fact, concentrations of hydrocarbons in the bile of Dolly Varden were some of the highest of any fish sampled in 1989. By 1990, theseconcentrations had dropped substantially.

Like the cutthroat trout, there is evidence from 1989-90 that Dolly Varden in a

small number of oiled index streams inPrince William Sound grew more slowlythan in unoiled streams. It was hypothesizedthat the slower rate of growth in oiledstreams was the result of reduced food supplies or exposure to oil, and there was concern that reduced growth rates would result

Photo by Roy CorralKenai Fjords National Park

Park. Six moderately to heavily oiled siteson the Kenai and Katmai coasts were lastsurveyed in 1994, at which time some oilmousse persisted in a remarkably unweathered state on boulder-armored beaches atfive sites. These sites will be visited againin 1999. Pending completion of these visits, and additional visits to oiled shorelines

in western Prince William Sound, the recovery status of designated wildernessremains unknown.Recovery Objective

Designated wilderness areas will haverecovered when oil is no longer encounteredin them and the public perceives them to berecovered from the spill.

in reduced survival. However, these growthdifferences did not persist into the 1990-91winter. No growth data have been gathered

since 1991.In a 1991 restoration study sponsoredby the Trustee Council, some tagged DollyVarden moved considerable distancesamong streams within Prince WilliamSound, suggesting that mixing of overwintering stocks takes place during the summersin saltwater. This hypothesis is supportedby preliminary data from another TrusteeCouncil-sponsored study, which indicatesthat Dolly Varden from different locationsacross the sound are genetically similar. Thefinal report on this genetics study is due in

1999, but if this preliminary conclusion isborn out, it would suggest that the DollyVarden population in the sound should havelittle difficulty in recovering from any initial growth-related effects. Pendingcompletion of the genetics work and absent additional growth data, however, it

is prudent to continue classifying theDolly Varden as recovery unknown.

The Trustee Council sponsored inventories of streams in and around Prince William Sound to identify Dolly Varden habitat and the presence or absence of this species. Information from these inventorieshas been added to the Alaska Departmentof Fish and Games Anadromous WatersCatalog, and this step brings to bear additional legal protection under state law inregard to actions affecting these streams.Additional habitat for Dolly Varden hasbeen protected from among the more than280 anadromous fish streams that havebeen acquired through the Trustee

Councils habitat protection program.

Recovery ObjectiveDolly Varden will have recovered when

growth rates within oiled streams are comparable to those in unoiled streams, aftertaking into account geographic differences.


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HHHHH ARLEQUINARLEQUINARLEQUINARLEQUINARLEQUIN DDDDD U C K SU C K SU C K SU C K SU C K S

Injury and RecoveryHarlequin ducks feed in intertidal and

shallow subtidal habitats where most of thespilled oil was initially stranded. More than200 harlequin ducks were found dead in1989, mostly in Prince William Sound.Many more than that number probably diedthroughout the spill area. Because the spilloccurred in early spring before winteringharlequins migrated from the sound to inland breeding sites, the initial effects of thespill were likely extended beyond the immediate spill zone. The geographic extentof these extended impacts is not known.

The current overwintering population of harlequin ducks in Prince William Sound ison the order of 18,000 ducks, while the summer population is about half that number.Fall boat surveys designed specifically tomonitor molting-wintering harlequin ducksindicate a significant declining trend in thewestern sound. Other boat surveys designedto monitor an entire suite of marine birds inthe sound have shown mixed results: an increasing trend in March but no increase inJuly through 1996. All three surveys, however, are consistent in that they show different or lower trends for harlequin ducks inoiled parts of the sound compared to unoiled

parts.Prespill data on harlequin populationsand reproductive success are limited anddifficult to interpret, but previously there wasconcern about poor reproductive success inthe western versus eastern parts of PrinceWilliam Sound. This concern was based onobservations of 7-15 broods in the easternsound and few-to-no reports of broods in thewestern sound when comparable numbersof streams were surveyed. Subsequent research does not indicate any differences inthe age- and sex-structure of harlequin popu

lations in the eastern and western parts of the sound, but it is clear that the breedinghabitat in the western sound is very limitedcompared to what is available in the easternsound. Some harlequins remain in the soundto nest, mostly on the eastern side, but it isnow suspected that most harlequins of breed

ing age and condition probably leave thesound altogether to nest in interior drainages.Thus, conclusions of reproductive failurebased on lack of broods in the oiled area donot now seem warranted.

Biopsies from samples of harlequinducks collected early in 1998 and fromBarrows goldeneye in the 1996-1997 winter continue to show differences in an enzyme indicative of exposure to hydrocarbons between birds from oiled versusunoiled parts of the sound. These differences are consistent with the possibility of continued exposure to hydrocarbons in theoiled western sound. The biological effectof this possible exposure has not been established, but three years of data (1995/96-97/98 winters) on overwintering survivalof adult female harlequins indicate significantly lower survival rates in oiled versusunoiled parts of the sound. This result cannot be attributed unequivocally to oil exposure, but there is reason for concernabout possible oil exposure and reducedsurvival for harlequin ducks in the westernsound. This information, coupled withindication of a possible on-going declinein numbers of molting harlequin ducksin the western sound, suggest that the

harlequin duck has not recovered fromthe effects of the oil spill.Recent Trustee Council-sponsored stud

ies give insight into prospects for recoveryof harlequin ducks. Although some harlequin ducks make major seasonal movements, they exhibit high site fidelity to summer breeding sites and to molting and wintering sites during nonbreedingseasons. Strong site fidelitymay limit population recoveryby immigration, but a geneticanalysis of harlequin ducks in

dicates that the spill-area population is homogeneous (i.e., verysimilar). Taken together, thesedata are consistent with a lowrate of dispersal, perhaps at thesubadult stage, or a rapid expansion of the population in recent

geological time. To the extent that there issubadult dispersal from adjacent expandingpopulations, such dispersal would enhancerecovery. It is likely, however, that recov

ery will largely depend on recruitment andsurvival from within injured populations.This recovery may be compromised if exposure to lingering hydrocarbons reducesfitness and survival of harlequin ducks

The Trustee Council has made a ma jor investment in harlequin ducks, studying the possibility of on-going oil-relatedeffects, gaining knowledge that will benefit long-term management and conservation, and protecting nesting and overwintering habitats. Harlequin ducks nest alonganadromous fish streams, typically underforest cover and at higher elevations. Someof the more than 280 anadromous fishstreams protected with the support of theTrustee Council provide nesting habitat forharlequin ducks. Molting and overwintering habitats are protected along the morethan 1,200 miles of marine shorelines acquired through the habitat protection program. As a result, the terrestrial portion of the habitat base for harlequin ducks in thespill area is now significantly more secure.

Recovery ObjectiveHarlequin ducks will have recoveredwhen breeding- and nonbreeding-seasondensities return to prespill levels. An increasing population and decreasing indications of exposure to hydrocarbons in oiledparts of Prince William Sound will indicatethat recovery is underway.

Harlequin Duck


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HHHHH ARBORARBORARBORARBORARBOR SSSSS EALSEALSEALSEALSEALS

Injury and RecoveryHarbor seal numbers were declining in

the Gulf of Alaska, including in Prince William Sound, before the oil spill. ExxonValdez oil affected harbor seal habitats, including key haul-out areas and adjacentwaters, in Prince William Sound and as faraway as Tugidak Island, near Kodiak. Estimated mortality as a direct result of the oilspill was about 300 seals in oiled parts of Prince William Sound. Based on aerial surveys conducted at trend-count haulout sitesin central Prince William Sound before(1988) and after (1989) the oil spill, seals inoiled areas declined by 43 percent, comparedto 11 percent in unoiled areas.

In a declining population deaths exceedbirths, and harbor seals in both oiled andunoiled parts of Prince William Sound havecontinued to decline since the spill. For theperiod 1989-1997, the average estimatedannual rate of decline was about 5 percent,and for that reason harbor seals continueto be considered not recovered. Environmental changes in the late 1970s may havereduced the amount or quality of prey resources, including such forage fishes as Pacific herring and capelin, available to harborseals in the northern Gulf of Alaska ecosys-

IIIII NTERTIDALNTERTIDALNTERTIDALNTERTIDALNTERTIDAL COMMUNITIESCOMMUNITIESCOMMUNITIESCOMMUNITIESCOMMUNITIES

Injury and RecoveryPortions of 1,300 miles of coastline

were oiled by the spill in Prince WilliamSound, on the Kenai and Alaska peninsulas,and in the Kodiak Archipelago. Both theoil and intensive clean-up activities had significant impacts on the flora and fauna of the intertidal zone, the area of beach betweenlow and high tides. Intertidal communities

are intrinsically important and are resourcesfor subsistence users, sea and river otters,and a variety of birds, including black oystercatchers, harlequin ducks, and pigeonguillemots.

Initial impacts to intertidal organismsoccurred at all tidal levels and in all types of

tem. These changesmay have been responsible for or contributed to the initialprespill harbor sealdecline, and the ecosystem may nowsupport fewer seals

Harbor Seal than it did prior tothe late 1970s. Recent studies, however, indicate that the seals in the sound, especiallypups and yearlings, are in very good condition and do not show evidence of nutritionalstress. On-going sources of mortality includekiller whale predation, subsistence hunting,and commercial fishery interactions (e.g.,

drowning in nets). Satellite tagging studiessponsored by the Trustee Council indicate thatharbor seals in the sound are largely residentthroughout the year, suggesting that recovery must come largely through recruitmentand survival within injured populations.

Harbor seals have been a major focusof research sponsored by the Trustee Council since the oil spill. This research includesdocumentation of population trends in thefield, improved statistical techniques for theanalysis of aerial survey data, and exploration of possible sources of mortality and lack

habitats throughout the oil-spill area. Manyspecies of algae and invertebrates were lessabundant at oiled sites than at unoiled reference sites. Some, more opportunistic species, including a small species of barnacle,oligochaete worms, and filamentous brownalgae, colonized shores affected by the oilspill and clean-up activities. The abundanceand reproductive potential of the common

seaweed, Fucus gardneri (known as rockweed or popweed), also was reduced following the spill.

In the lower and middle intertidalzones on oiled rocky shores, algal coverage and invertebrate abundances had returned by 1991 to coverages and abun

of recovery in the population, includinghealth and diet. One study quantified normal blood chemistry values for several hundred seals; this database serves as a valuable tool for evaluating the health status of other seals. Starting in 1998, several projectsexploring blood chemistry and other healthparameters in relation to diet are being carried out at the Alaska SeaLife Center.

Harbor seals have long been a key subsistence resource in the oil-spill area. Subsistence hunting is affected by the declining seal population, and fewer opportunities to hunt seals have changed the diets of subsistence users who traditionally reliedon these marine mammals. With partial

support from the Trustee Council, theAlaska Native Harbor Seal Commission isworking to involve Native hunters in research on and management of harbor seals.Alaska Native subsistence hunters havebeen helpful by providing seal researcherswith measurements and hard-to-obtain tissue samples from harvested seals.

Recovery ObjectiveHarbor seals will have recovered from

the effects of the oil spill when their population is stable or increasing.

dances similar to those observed in unoiledareas. However, large fluctuations in thealgal coverage took place through 1997 inthe oiled areas. This pattern is consistentwith continued instability due to the original spill impact and the subsequentcleanup.

On the sheltered, bedrock shores thatare common in Prince William Sound, fullrecovery of Fucus is crucial for the recovery of intertidal communities at these sites,since many invertebrate organisms dependon the cover provided by this seaweed. Fu- cus has not yet fully recovered in the upper intertidal zone on shores subjected todirect sunlight, but in many locations, re-


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covery of intertidal communities has beensubstantial. In other habitat types, such asestuaries and cobble beaches, many speciesdid not show signs of recovery when theywere last surveyed in 1991. In studies of theeffects of cleanup activities on beaches, in

vertebrate molluscs and annelid worms onoiled and washed beaches were still muchless abundant than on comparable unoiledbeaches through 1997.

Beyond describing the effects of the oilspill and cleanup operations, the TrusteeCouncils restoration program has benefitedintertidal communities in several respects.

KKKKK ITTLITZITTLITZITTLITZITTLITZITTLITZ SSSSS MMMMM URRELETSURRELETSURRELETSURRELETSURRELETS

Injury and RecoveryThe Kittlitzs murrelet is found only in

Alaska and portions of the Russian Far East.A large fraction of the world population,which may number only a few tens of thousands, breeds in Prince William Sound. TheKenai Peninsula coast and Kachemak Bay arealso important concentration areas for thisspecies. Very little is known about Kittlitzsmurrelets, but they are known to associateclosely with tidewater glaciers and nest onscree slopes and similar sites on the ground.

Seventy-two Kittlitzs murrelets were

positively identified among the bird carcassesrecovered after the oil spill. Nearly 450 more Brachyramphus murrelets were not identifiedto the species level, and it is reasonable toassume that some of these were Kittlitzs. Inaddition, many more murrelets probably werekilled by the oil than were actually recovered.

KKKKK ILLERILLERILLERILLERILLER WWWWW HALESHALESHALESHALESHALES

Injury and Recovery

More than 100 killer whales in six resident pods regularly use Prince WilliamSound as part of their ranges. Other whalesin transient groups are observed in thesound less frequently. There has been particular concern in the sound about the resident AB pod, which numbered 36 animals

Although most tidelands in the spill area arealready in state ownership, Trustee Councilfunds enabled the protection of sedge andmudflat habitats on the Homer Spit and enhanced protection of and access to rockyintertidal habitats at Kachemak Bay and at

Lowell Point near Seward. Research andmonitoring sponsored by the Trustee Council have greatly expanded knowledge of thedistribution and ecology of north Pacific intertidal organisms, such as sea stars, andhave provided models for statistically powerful sampling designs that can be incorporated into future injury assessments.

One published estimate places direct mortality of Kittlitzs murrelets from the oil spill ashigh as 1,000-2,000 individuals, which wouldrepresent a substantial fraction of the worldpopulation.

Because so little is known about this species, the Trustee Council funded an exploratory study on the ecology and distributionof the Kittlitizs murrelet in Prince WilliamSound starting in 1996. Final results fromthis project are not yet available, but preliminary data confirm this species affinity fortidewater glaciers in the four bays studied in

the northern and northwestern parts of thesound. It also appears that reproductive output in 1996 and 1997 was extremely low orabsent, and some Kittlitzs murrelets wereapparently paired with marbled murrelets.There appear to be about 1,200-1,400Kittlitzs murrelets during summer in the four

prior to the spill. Fourteen whales disap

peared from this pod in 1989 and 1990, during which time no young were recruited intothe population. During the period 1992-94,four calves were added to the pod, but fiveadditional adults were lost and presumeddead. During the most recent period, 199698, fives calves were recruited and only two

Recovery ObjectiveIntertidal communities will have recov

ered when community composition on oiledshorelines is similar to that which wouldhave prevailed in the absence of the spill.Indications of recovery are the reestablish

ment of important species, such as Fucus asheltered rocky sites, the convergence incommunity composition and organism abundance on oiled and unoiled shorelines, andthe provision of adequate, uncontaminatedfood supplies for top predators in intertidaland nearshore habitats.

bays studied in northern and northwesternsound. Other, more extensive marine birdboat surveys suggest a sound-wide summerpopulation of at least 3,400 murrelets. Theseestimates are consistent with what is believedto be a small Alaskan and world population.

The population data, indications of lowreproductive success, and affinity to tidewater glaciers (of which the lower elevation glaciers are receding rapidly) are reasons forconcern about the long-term conservation of Kittlitzs murrelets. Specifically with reference to the effects of the oil spill, however,the original extent of the injury and its recovery status are still unknown and maynever be resolved.

Recovery ObjectiveNo recovery objective can be identified

for Kittlitzs murrelet at this time.

adults were losta net gain of three individu

als since 1992. If the calves born since 1992survive and if additional calves are added tothe pod over the next two or more years, therequirements for recovery will have been satisfied. Pending evidence of sustained recruitment or at least stability, the kill whaleis still considered to be not recovering.


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The original link between the AB podlosses and the oil spill was circumstantial.The rate of disappearance and likely mortality of killer whales in this well-studied podin Prince William Sound following the spillfar exceeded rates observed for other pods in

British Columbia and Puget Sound over thelast 20 years. In addition to the effects of theoil spill, there had been concern about thepossible shooting of killer whales due to conflicts with long-line fisheries prior to the oilspill. There are no recent indications of suchconflicts.

Overall numbers within the major resident killer whale pods in Prince WilliamSound are at or exceed prespill levels, eventhough the AB pod may or may not regain itsformer size. There is concern, however, thata decline in resightings of individuals within

the AT1 group of transient killer whales hasaccelerated following the oil spill. Since 1990and 1991, 10 individuals have been missingfrom the AT group and are now almost certainly dead. During that same period therehas been no recruitment of calves into this

group of transients. Transient killer whaleslargely prey on marine mammals, and therehas been a 60 percent decline in the harborseal population in the sound over the last twodecades. Changes in the availability of suchan important prey species could influence

killer whale distribution and reproduction.Trustee Council-sponsored research oncontaminants in killer whales in Prince William Sound indicates that some whales arecarrying high concentrations of PCBs, DDT,and DDT metabolites in their blubber. Thepresence of such contaminants is not relatedto the oil spill. Contaminants are significantlyhigher in the mammal-eating transients thanin the fish-eating residents, consistent withthe fact that contaminants bioaccumulatethat is they are more concentrated at highertrophic levels. Concentrations are highest in

first-born calves, indicating that contaminantsare passed on by nursing females. The highconcentrations of contaminants found in thetransient whales, including those in the AT1group, are comparable to those found to causereproductive problems in other marine mam

mals, but there is no unequivocal evidenceof a link between contaminants and poor reproduction in the AT1 group.

Other work sponsored by the TrusteeCouncil includes a detailed genetic analysisthat has shown definitively that resident and

transient killer whales in Prince WilliamSound are genetically distinct. The TrusteeCouncil also has sponsored development of acoustic techniques for identifying and monitoring killer whales. Data on sightings andmovements of killer whales indicate that thearea around Knight Island and passages toKnight Island are among the most heavilyused parts of Prince William Sound by bothresident and transient killer whales. Use of the outer Kenai coast, including ResurrectionBay, appears to be increasing.

Recovery ObjectiveKiller whales in the AB pod will have

recovered when the number of individualsin the pod is stable or increasing relative tothe trends of other major resident pods inPrince William Sound.

Killer Whale


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MMMMM ARBLEDARBLEDARBLEDARBLEDARBLED MMMMM URRELETSURRELETSURRELETSURRELETSURRELETS

Injury and RecoveryThe northern Gulf of Alaska, including

Prince William Sound, is a key area of concentration in the distribution of marbledmurrelets. The marbled murrelet is federally listed as a threatened species in Washington, Oregon, and California; it also islisted as threatened in British Columbia.

The marbled murrelet population inPrince William Sound had declined beforethe oil spill. The causes of the prespill decline are not known for certain, but environmental changes in the late 1970s probably reduced the availability or quality of prey resources. There is, nonetheless, clearevidence that oil caused injury to marbledmurrelets in the sound. Carcasses of nearly

1,100 Brachyramphus murrelets were foundafter the spill, and about 90 percent of themurrelets that could be identified to the species level were marbled murrelets. Manymore murrelets probably were killed by theoil than were found, perhaps as much as 7percent of the spill area population.

The recovery of the marbled murreletpopulation in Prince William Sound is assessed primarily through standard marinebird boat surveys. Based on a recent analysis of data from boat surveys carried out inJuly for most years from 1989-1998, densi-

MMMMM USSELSUSSELSUSSELSUSSELSUSSELS

Injury and RecoveryMussels are an important prey species

in the nearshore ecosystem throughout thespill area and are locally important for subsistence. Beds of mussels provide physicalstability and habitat for other organisms inthe intertidal zone and were purposely leftalone during Exxon Valdez cleanup opera

tions.In 1991, high concentrations of relatively

unweathered oil were found in the musselsand in underlying byssal mats and sedimentsin certain dense mussel beds. The biologicalsignificance of mussel beds that are still oiledis not known precisely, but they are potential

ties of marbled murrelets increased substantially in oiled parts of the sound during 19901993, but declined again in 1996 and 1998.Densities of murrelets in unoiled parts of thesound also declined in 1996 and 1998, sothe reason for the recent declines in bothoiled and unoiled areas is probably due tosome factor other than the oil spill.

The Trustee Councils recovery objective requires a stable or increasing population for marbled murrelets; stable or increasing productivity would indicate that recovery is underway. The marbled murreletpopulation is not now stable nor increasing,but the increase in oiled areas from 19901993 is a positive sign. In addition, marbledmurrelet productivity, as measured by sur

veys of adults and juveniles on the water inPrince William Sound, appears to be withinnormal bounds. On these bases, it appearsthat the marbled murrelet is at least recovering from the effects of the oil spill.

Marbled murrelets have been a majorfocus of the Trustee Councils restorationprogram, including both habitat protectionand research and monitoring activities.Marbled murrelets are known to nest inlarge, mossy trees within stands of old-growth forest. Following the oil spill,Trustee Council researchers identified spe

pathways of oil contamination for local populations of harlequin ducks, black oystercatchers, river otters, and sea otters, all of whichfeed to some extent on mussels and other preyin and around mussel beds and which wereinjured by the oil spill. The Trustee CouncilsNearshore Vertebrate Predator project hasevidence of possible hydrocarbon exposure

in sea otters, river otters, harlequin ducks, andBarrows goldeneyes in oiled parts of PrinceWilliam Sound through 1996 or 1997, but thepathway of such exposure has not been established.

About 30 mussel beds in Prince William Sound still contained Exxon Valdez oil

cific habitat types and areas within the spillzone that are especially valuable to nestingmurrelets. Much of the 600,000 acres of habitat protected with Trustee Council fundsis forested, including significant habitat thatis suitable for and used by nesting murrelets(for example, on Afognak Island).

In the area of research and monitoring,the Trustee Councils Alaska Predator Ecosystem Experiment (APEX) project is investigating the relationship between marbledmurrelet declines and the availability andabundance of forage fish, such as Pacificherring, sand lance, and capelin. It appearsthat there is a direct correlation between theavailability of forage fish and production of young murrelets, based on the presence of

juvenile murrelets on the water in PrinceWilliam Sound. Historical trawl data analyzed as part of this project supported a decision by the North Pacific Fishery Management Council to limit bycatch of forage fishin commercial fisheries and to preclude thestartup of fisheries targeting forage fish (notincluding herring).Recovery Objective

Marbled murrelets will have recoveredwhen their populations are stable or increasing. Stable or increasing productivity willbe an indication that recovery is underway.

residue when last sampled in 1995. Twelveof these beds had been cleaned on an experimental basis in 1993 and 1994. In 1995, oilhydrocarbon concentrations in mussels at half the treated beds were lower than would havebeen expected if the beds had not beencleaned. In 1996, however, limited samplingindicated that several of the cleaned beds had

been recontaminated from surrounding orunderlying oil residue.Mussel beds along the outer Kenai Pen

insula coast, the Alaska Peninsula, andKodiak Archipelago were surveyed for thepresence of oil in 1992, 1993, and 1995. In1995, hydrocarbon concentrations in mussels


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and sediments at these Gulf of Alaska siteswere generally lower than for sites in PrinceWilliam Sound, but at some sites substantialconcentrations persist.

While several sites in Prince WilliamSound still contained high concentrations of

oil in 1995, over half the sites surveyed demonstrated significant natural declines that suggest background concentrations should bereached in the next few years. On this basis,

PPPPP ACIFICACIFICACIFICACIFICACIFIC HHHHH ERRINGERRINGERRINGERRINGERRING

Injury and RecoveryPacific herring spawned in intertidal

and subtidal habitats in Prince WilliamSound shortly after the oil spill. A significant portion of these spawning habitats aswell as herring staging areas in the soundwere contaminated by oil. Field studies conducted in 1989 and 1990 documented increased rates of egg mortality and larval deformities in oiled versus unoiled areas. Subsequent laboratory studies confirm that theseeffects can be caused by exposure to ExxonValdez oil, but the significance of these in

juries at a population level is not known.The 1988 prespill year-class of Pacific

herring was very strong in Prince WilliamSound, and, as a result, the estimated peak biomass of spawning adults in 1992 wasvery high. Despite the large spawning biomass in 1992, the population exhibited adensity-dependent reduction in size, and in1993 there was an unprecedented crash of the adult herring population. A viral diseaseand fungus were the probable immediateagents of mortality, but such other factorsas competition for food may have reducedherring fitness and survival. Laboratory investigations since the population crash haveshown that exposure to very low concentrations of Exxon Valdez oil can compromise

the immune systems of adult herring andlead to expression of the viral disease. Theextent to which the exposure to oil contributed to the 1993 disease outbreak is uncertain.

Numbers of spawning herring in PrinceWilliam Sound remained depressed through

mussels are considered to be recovering. Oilcontamination in mussels, however, willlikely persist for many years at certain sitesthat are well protected from wave action orwhere oil penetrated deeply into underlyingsediments.

In 1999, a series of oiled mussel bedswill be inspected and monitored to track therecovery of this resource. Comparison of mussel beds cleaned in 1994 to beds that were

the 1995 season. In 1997 and 1998 thespawning biomass was about double that of 1994, the season following the crash, andthere were limited commercial harvests forherring in the sound. , The increased biomasses in 1997 and 1998 are signs that recovery has begun. Unfortunately, the population has yet to recruit a highly successfulyear-class, which is fundamental to recovery of this species. Thus, a full recoveryhas not been achieved, and the Pacificherring can only be considered to be recovering.

Because the Pacific herring is extremelyimportant ecologically and commerciallyand for subsistence users, the Trustee Council has made a major investment in restoration projects that benefit herring. In the areaof habitat protection, Trustee Council fundshave acquired more than 1,200 miles of upland shorelines, some of which will helpprotect water quality in areas used by spawning herring. Research sponsored by theTrustee Council also has identified bays thatare important as herring nursery and overwintering areas, and this information will beuseful to natural resource managers for decisions about siting facilities or planningresponses to future oil spills.

The Trustee Councils Sound Ecosys

tem Assessment has resulted in new understanding of the importance of body condition in determining overwintering survivalof herring and in the influences of the Gulf of Alaska in herring productivity withinPrince William Sound. Techniques for improving stock and spawning biomass assess-

not cleaned should provide valuable information for planning responses to future oil spills.

Recovery ObjectiveMussels will have recovered when con

centrations of oil in the mussels and in the

sediments below mussel beds reach background levels, do not contaminate their predators, and do not affect subsistence uses.

ments through spawn deposition surveys andhydroacoustic and aerial surveys also havebeen supported by the Trustee Council. Ongoing research on herring disease in relation to commercial fishing practices, suchas the enclosed pound fisheries, have direct implications for management of theherring fishery. Improvements in knowledgeabout the biology and ecology of herring andin assessment and management tools willenhance conservation and management of this species over the long term.

Recovery ObjectivePacific herring will have recovered

when the next highly successful year classis recruited into the fishery and when other

indicators of population health are sustainedwithin normal bounds in Prince WilliamSound.

Pacific Herring


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PPPPP IGEONIGEONIGEONIGEONIGEON GGGGG UILLEMOTSUILLEMOTSUILLEMOTSUILLEMOTSUILLEMOTS

Injury and RecoveryAlthough pigeon guillemots are widely

distributed in the north Pacific region, nowheredo they occur in large concentrations. Becauseguillemots feed in shallow, nearshore waters,the guillemots and the fish on which they preyare vulnerable to oil pollution.

Like the marbled murrelet, there is evidence that the pigeon guillemot population inPrince William Sound declined before the oilspill. The causes of the prespill decline are notknown for certain, but environmental changesin the late 1970s probably reduced the availability or quality of prey resources. There is,nonetheless, clear evidence that oil caused in

jury to the guillemot population in the sound.An estimated 10-15 percent of the spill-areapopulation died immediately following thespill. Boat-based surveys of marine birds before (1984-85) and after the oil spill indicatedthat the guillemot population declined throughout the oiled portion of the sound. These samesurveys indicate that numbers of guillemots remain depressed along oiled shorelines

PPPPP I N KI N KI N KI N KI N K SSSSS ALMONALMONALMONALMONALMON

Injury and RecoveryCertain features of the life history of pink

salmon made this species highly vulnerable todamage from the oil spill. As much as 75 percent of wild pink salmon in Prince WilliamSound spawn in the intertidal portions of streams, where embryos deposited in the gravelcould be chronically exposed to hydrocarboncontamination in the water column or leaching from oil deposits on adjacent beaches.When juvenile pink salmon migrate to saltwater they spend several weeks foraging forfood in nearshore habitats. Thus, juvenilesalmon entering seawater from both wild and

hatchery sources could have been exposed tooil as they swam through oiled waters and fedalong oiled beaches. Trustee Council-spon-sored studies have documented two primarytypes of injury due to the exposure of theseearly life stages: First, growth rates in both wildand hatchery-reared juvenile pink salmon from

in the sound through 1998, and for this reason the pigeon guillemot is still consideredto have not recovered from the effects of the oil spill.

The Trustee Councils Alaska PredatorEcosystem Experiment (APEX) project is investigating the possible link between pigeonguillemot declines and the availability of high-quality forage fish, such as Pacific herring andsand lance. This work has revealed a strongconnection between the availability of certainprey fishes, especially sand lance, andguillemot chick growth rates, fledging weights,and nesting population size. Historical trawldata analyzed as part of this project supporteda decision by the North Pacific Fishery Management Council to limit bycatch of forage fishin commercial fisheries and to preclude thestartup of fisheries targeting forage fish (notincluding herring).

The Nearshore Vertebrate Predator (NVP)project, also sponsored by the Trustee Council,addresses the possibility that exposure to oil islimiting the guillemots recovery. Preliminary

oiled parts of the sound were reduced. Second, there was increased egg mortality in oiledversus unoiled streams.

In the years preceding the spill, returns of wild pink salmon in Prince William Sound varied from a maximum of 23.5 million fish in 1984to a minimum of 2.1 million in 1988. Since thespill, returns of wild pinks have varied from ahigh of about 12.7 million fish in 1990 to a lowof about 1.9 million in 1992. The decade preceding the oil spill was a time of very high productivity for pink salmon in the sound, and,given the tremendous natural variation in adultreturns, it is impractical to measure directly the

extent to which wild salmon returns since 1989were influenced by the oil spill. Based on intensive studies, including mathematical models, carried out following the spill, wild adultpink salmon returns to the sounds SouthwestDistrict in 1991 and 1992 were most likely reduced by a total of 11 percent.

biochemical data do not indicate that guillemotchicks are being exposed to hydrocarbons.

Pigeon guillemots nest in rock crevicesand under tree roots at the tops of rocky cliffs

and steep slopes. They have benefited greatlyfrom the habitat protection program, including the acquisition of more than 1,200 milesof marine shoreline. In addition, introducedfoxes were eliminated from two of theShumagin Islands (Simeonof andChernabura) in the southwestern part of thespill area. Pigeon guillemots were present inlow densities on both islands, but in higherdensities on nearby fox-free islands. Although the nesting birds have not been surveyed since the foxes were removed in 1995,the elimination of this introduced predatorshould result in a large increase in the population of nesting guillemots.Recovery Objective

Pigeon guillemots will have recoveredwhen their population is stable or increasing.Sustained productivity within normal boundswill be an indication that recovery is underway.

Reduced juvenile growth rates in PrinceWilliam Sound occurred only in the 1989 season, but higher egg mortality persisted in oiledcompared to unoiled streams through 1993.No statistically significant differences in eggmortalities in oiled and unoiled streams weredetected in 1994 through 1996, but in 1997there was again a difference. It is not clearwhether the 1997 difference was due to theeffects of lingering weathered oil, perhapsnewly exposed by storm-related disturbanceof adjacent beaches, or due to other factors.Patches of weathered oil still persist in or nearintertidal spawning habitats in a few of the

streams used by pink salmon in southwesternPrince William Sound. It is possible thatpatches of oil may be exposed as winter stormsshift stream beds back and forth and result inlocal episodes of increased pink salmon eggmortality. The duration, scale, and number of any such events now would be limited in com-


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parison to the situation that existed in the southwestern sound in 1989-1993. Therefore, thebiological impact of exposure to any such lingering oil is unlikely to limit pink salmonpopulations, assuming there are no drasticnegative changes in the quality of freshwater

habitats and ocean rearing conditions.Since the Trustee Councils recoveryobjective specifically requires a sequence of two years each of odd- and even-year runswithout differences in egg mortality, this recovery objective clearly has not been met.Thus, the Trustee Council continues to findthat pink salmon are recovering from theeffects of the oil spill, but that full recoveryhas not been achieved.

The Trustee Council has made a majorinvestment in studying the effects of the oilspill on pink salmon and in improving conser

vation and management of wild stocks inPrince William Sound. Studies on the effectsof oil on pink salmon have led to new insightsabout how oil can affect salmon, especially inregard to the toxicity of even very small concentrations of weathered oil on early life stages.This information will be useful in evaluatingwater quality standards for oil in water and incontingency planning for future oil spills.

The Trustee Council has sponsored several projects directed at improved management

RRRRR IVERIVERIVERIVERIVER OOOOO TTERSTTERSTTERSTTERSTTERS

Injury and RecoveryRiver otters have a low population den

sity in Prince William Sound. Twelve riverotter carcasses were found following the spill,but the actual total mortality is not known.Studies conducted during 1989-91 identifiedseveral differences between river otters inoiled and unoiled areas in Prince WilliamSound, including biochemical alterations,reduced diversity in prey species, reducedbody size (length-weight), and increased

home-range size. Because there were fewprespill data, it is not certain that these differences are the result of the oil spill. Althoughsome of the differences (e.g., in blood values) persisted through 1996, there were fewdifferences documented in 1997 and 1998.Thus, there are no indications of possible

of pink salmon. One of the most beneficialprojects sponsored by the Trustee Council wasdevelopment and implementation of a thermalmass marking project in Prince William Sound.This project, which is now being sustained bythe Alaska Department of Fish and Game and

the Prince William Sound Aquaculture Association, puts a unique mark on the otoliths (earbone) of hatchery-reared fry released in thesound. Technicians can readily identify thesefish when they are caught as returning adults.This information is used for in-season adjustments of harvests (times and areas) to betterprotect wild stocks and to more fully utilizehatchery stocks when doing so does not jeopardize wild stocks of pink salmon. Anotherproject sponsored by the Trustee Council characterized the genetic stock structure of pink salmon in the sound. The results of this project

will improve confidence that management actions are adequately protecting the genetic diversity of small wild stocks.

Throughout Alaska there is increasingrecognition of the importance of changes inmarine ecosystems on the growth and survivalof salmon. The Trustee Council has fundedthe Sound Ecosystem Assessment (SEA)project to explore oceanographic and ecological factors that influence production of pink salmon and Pacific herring in Prince William

lingering injury from the oil spill, and theTrustee Councils recovery objective hasbeen met.

The Trustee Councils habitat protectionprogram and research and monitoringprojects have benefited spill-area river otters. More than 1,200 miles of marine shoreline and more than 280 streams used byanadromous fish streams have been protected; much of this area provides high-valuehabitat for river otters.

Through the Nearshore VertebratePredator project and other studies, much information has been gathered that will improve long-term conservation and management of river otters. These breakthroughsinclude development of a new method forlive-trapping otters, which will improve the

Sound. These factors include such things asthe timing of spring plankton blooms andchanges in circulation patterns that link thesound to the Gulf of Alaska. These naturalfactors are likely to have the greatest influenceon year-to-year returns in both wild and hatch

ery stocks of pink salmon. A final report fromthe SEA Project is due at the end of FY 1999.Pink salmon have been major beneficia

ries of the Trustee Councils habitat protection program. The more than 600,000 acresof land protected through the Trustee Councilprogram include 280 streams with spawningand rearing habitat for salmon. Wild populations of pink salmon have been enhanced bycreating or providing access to additionalspawning habitat, such as the Port Dick spawning channel on the outer Kenai coast. Thisproject is expected to result in production of

additional pink salmon available for commercial harvest each year.

Recovery ObjectivePink salmon will have recovered when

population indicators, such as growth and survival, are within normal bounds and there areno statistically significant differences in eggmortalities in oiled and unoiled streams for twoyears each of odd- and even-year runs in PrinceWilliam Sound.

ability of wildlife managers to estimatepopulation sizes for this elusive species, andnew insights in the recycling of aquatic nutrients into forest ecosystems at otter latrinesites, which has important implications froma conservation standpoint. In addition, work in progress at the Alaska SeaLife Center onthe blood chemistry of river otters in relation to small doses of oil will aid interpretation of biochemical tests for exposure fromoil and other contaminants.

Recovery ObjectiveThe river otter will have recovered whenbiochemical indices of hydrocarbon exposureor other stresses and indices of habitat useare similar between oiled and unoiled areasof Prince William Sound, after taking intoaccount any geographic differences.


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RRRRR OCKFISHOCKFISHOCKFISHOCKFISHOCKFISH

Injury and RecoveryVery little is known about rockfish

populations (of several species) in the northern Gulf of Alaska. A small number of deadadult rockfish was recovered following theoil spill, and autopsies of five specimensindicated that oil ingestion was the cause of death. Analysis of other rockfish showedexposure to hydrocarbons and probable sublethal effects. In addition, closures to salmon

SSSSS E AE AE AE AE A OOOOO TTERSTTERSTTERSTTERSTTERS

Injury and RecoveryBy the late 1800s, sea otters had been

eliminated from most of their historicalrange in Alaska due to excessive harvesting by Russian and American fur traders.Surveys of sea otters in the 1970s and1980s, however, indicated a healthy and expanding population in most of Alaska, including Prince William Sound. Today theonly harvests of sea otters are for subsistence purposes.

About 1,000 sea otter carcasses wererecovered following the spill, and additional animals probably died but were notrecovered. In 1990 and 1991, higher-than-expected proportions of prime-age adult seaotters were found dead in western PrinceWilliam Sound, and there was evidence of higher mortality of recently weaned juveniles in oiled areas. By 1992-93, overwintering mortality rates for juveniles had decreased, but were still higher in oiled thanin unoiled parts of the sound.

Based on both aerial and boat surveysconducted in western Prince William Sound,there is statistically significant evidence of

a population increase following the oil spill(1993-98). Observations by local residentsbear out this general increase. However,within the most heavily oiled bays in thewestern sound, such as those on northernKnight Island, the aerial surveys indicate thatrecovery may not be complete.

fisheries apparently had the effect of increasing fishing pressures on rockfish, which, inturn, may have adversely affected local rockfish populations. However, the original extent of injury and the current recoverystatus of this species are unknown.

Because little is known about rockfishabundance and species composition in thespill area and because rockfish are harvestedcommercially, even basic information aboutthese species could provide a basis for im-

Photo by Robert Angell Sea Otter

The Trustee Councils Nearshore Vertebrate Predator project, which was startedin 1995, is addressing the lack of recoveryin sea otters in the heavily oiled bays of western Prince William Sound. The lack of recovery may reflect the extended timerequired for population growth for a long-lived mammal with a low reproductive rate,but it also could reflect the effects of continuing exposure to hydrocarbons or a combination of both factors. Through 1997,researchers have continued to find biochemical evidence of oil exposure in seaotters on northern Knight Island. Biochemical samples from 1998 are now being analyzed. An additional hypothesis isthat food supplies are limiting recovery, butpreliminary evidence does not fully support this idea.

It is clear that sea otter recovery isunderway for much of the spill-area, withthe exception of populations at the most

proved management or, at least, the identification of priorities for more targeted research.Accordingly, starting in FY 1998, the TrusteeCouncil sponsored a multi-year study of genetic stock structure in black, dusky, andyelloweye rockfish throughout the spill areaand the adjacent Gulf of Alaska. No resultsfrom this work are currently available.

Recovery ObjectiveNo recovery objective can be identified.

heavily oiled bays in western Prince Wil

liam Sound. Researchers sponsored by theTrustee Council continue to explore hypotheses for lack of recovery at these sites.

Sea otters have benefited from manyaspects of the Trustee Councils program.Sea otters are found along many miles of the more than 1,200 miles of marine shoreline that has been protected through thehabitat protection program. Results of research and monitoring projects have alsobeen valuable. For example, an aerial survey protocol is now being used more widelyto monitor sea otter populations, and an improved and validated technique for agingsea otters using their teeth will aid biologists and veterinarians wherever sea ottersare found. Another example is new information on age-specific reproductive rates,which is crucial for understanding the effects of subsistence harvests on sea otters.These new techniques and insights will aidsea otter conservation and managementover the long term.

Recovery Objective

Sea otters will have recovered whenthe population in oiled areas returns to itsprespill abundance and distribution. An increasing population trend and normal reproduction and age structure in westernPrince William Sound will indicate thatrecovery is underway.


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SSSSS EDIMENTSEDIMENTSEDIMENTSEDIMENTSEDIMENTS

Injury and Recovery Exxon Valdez oil penetrated deeply into

cobble and boulder beaches that are common on shorelines throughout the spill area,especially in sheltered habitats. Cleaningand natural degradation removed much of the oil from the intertidal zone, but visuallyidentifiable surface and subsurface oil persists at many locations.

The last comprehensive survey of shorelines in Prince William Sound, conducted in 1993, included 45 areas of shoreline known to have had the most significantoiling. The average location with surfaceoil residue, asphalt, or mousse was 160 m 2

in size. Based on that survey, it was estimated that heavy subsurface oil had decreased by 65 percent since 1991 and thatsurface oil had decreased by 50 percent overthe same time period.

The shorelines of the outer Kenai andAlaska Peninsula coasts get more wave action than most shorelines within Prince William Sound. These Gulf ofAlaska sites tendedto be contaminated with oil in the form of mousse, which can persist for long periods ina largely unweathered state. Five of six indexbeaches on the gulf coast have a heavy boulder armor, and were last visited in 1993 and

1994. At this time, surface and subsurface oilmousse persisted in a remarkably unweathered state in the armored beaches.

In 1995, a shoreline survey team vis-

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Injur

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