Toward sustainable ecosystem services from the Aleutian Archipelago

15 Pages·2005·0.2 MB·English

FISHERIES OCEANOGRAPHY Fish. Oceanogr. 14(Suppl. 1),277–291,2005
GUEST EDITORIAL
Toward sustainable ecosystem services from the Aleutian
Archipelago
J. D. SCHUMACHER (a.k.a. TWO CROW)1,* coordinate with a broad stakeholder community
AND GORDON H. KRUSE2 involving sectors of commercial and recreational fish-
1Two CrowEnvironmental, Inc., PO Box345, Gila, NM ing,subsistence,conservation,oilandgasdevelopment,
coastaldevelopment,shipping,tourism,andothers.
88038, USA
2Juneau Centre,School ofFisheries andOcean Sciences,
Key words: Aleutian Islands, climate change, eco-
University ofAlaska Fairbanks, 11120Glacier Highway,
system services, human use, integrative management
Juneau,AK 99801, USA
approach
ABSTRACT
INTRODUCTION
The new research reported in this special issue of
Fisheries Oceanography expands our understanding of The purpose of this supplement is to report results of
the Aleutian Archipelago ecosystem. Yet our know- recent research on aspects of the Aleutian Archipel-
ledge remains very limited, while the use of this eco- ago ecosystem, where field studies were conducted
system for commercial activities, recreation and other mainly between Samalga and Tanaga Passes (Fig. 1).
purposes expands. Given this situation, how can we In this Guest Editorial we integrate these results into
sustaintheecosystemservices(food,fuel,fibersaswell the framework of existing knowledge as a basis for
as spiritual, recreational, educational and other non- suggestingactionsleadingtosustainabilityofAleutian
materialbenefitstosociety)ofthisregion?Theregion ecosystem services. The term ecosystem services is
has a mixed history; healthy populations of many increasingly appearing in ecological literature (e.g.
speciesexist,butsodospeciesextinctions(e.g.Steller Anon., 2003; Palmer et al., 2004) in place of natural
sea cow, Hydrodamalis gigas) and population deple- resources, and is defined as food, fuels and fibers that
tions, including the sea otter (Enhydra lutris), Steller also provide spiritual, recreational, educational and
sea lion (Eumetopias jubatus), whiskered auklets numerous other non-material benefits to people.
(Aethiapygmaea),Pacificoceanperch(Sebastesalutus), We first discuss selected aspects of the Aleutian
and red king crabs (Paralithodes camtschaticus), associ- ecosystem, highlighting contributions appearing in
atedwith humanimpacts.Thesolutiontoourlimited this supplement, and then describe the circumstances
knowledge in this poorly studied region is increased thatresultedinavailabilityoffundingfortheresearch.
fundingforecosystemresearch,includingitsresponses The heart of this paper is a discussion of maintaining
to climate change and human impacts. Knowledge is sustainability ofecosystem services, which brings with
not sufficient, however; a change in management it research challenges and management issues. We
approach is also needed. We emphasize the need to conclude with a discussion of tools to attain sustain-
maintainabroadersetofecosystemservicesobjectives able ecosystem services in the Aleutian Archipelago.
rather than the traditional narrower focus on com-
mercial fishery yields. To do so, we recommend the
THEALEUTIANARCHIPELAGOECOSYSTEM
development of an integrated ecosystem services
management plan for the Aleutian Islands. Such a Topography
planrequiresthatstateandfederalregulatoryagencies TheAleutiansareachainofislandsforminganarcin
the northern North Pacific (NP) Ocean. The name
possibly originated from the Chukchi word ‘aliat’ for
*Correspondence. e-mail: [email protected] island (Wikipedia, 2005). The U.S. portion of this
Received 10June2005 archipelagoextendsmorethan2200 kmwestwardfrom
Revised version accepted 28June 2005 thewesternmarginoftheAlaskapeninsula(FalsePass)
(cid:1)2005Blackwell Publishing Ltd. 277
278 J.D. Schumacherand G.H.Kruse
Figure 1. Map of the Aleutian and
Commander Islands. The 200-m isobath
is shown as a thin line (after Hunt and
Stabeno,2005).
to Attu Island. The islands were formed by volcanic 2003), and the Northern Annular Mode (e.g. Over-
activity associated with the ongoing collision of the land et al., 1999; a.k.a. Arctic Oscillation). Rodionov
PacificandNorthAmericantectonicplates;thesetec- et al. (2005b) examined in depth the regional clima-
tonics also created a very narrow continental shelf, tology resulting from the interactions of the larger
(cid:1)80 kmatitswidestintheeasternAleutians.Across scale atmospheric features. The primary regional fea-
section of all the passes and the mean circulation fea- ture, the Aleutian Low, is a statistical feature that
turesareshowninStabenoet al.(2005).Followingthe results from frequent migration of storms eastward
nomenclatureofLaddet al.(2005a),theregioneastof along the archipelago (Schumacher et al., 2003). It is
SamalgaPass(justwestofUmnakIsland)istheeastern a prominent atmospheric centre of action in winter
Aleutian Islands, which are separated by relatively but practically disappears in summer (Rodionov et al.,
shallow (<100 m), narrow (<20 km) passes. The cen- 2005a,b). Rodionov et al. (2005b) identified a clima-
tral Aleutians extend from Samalga Pass west to Am- tological transition zone (at (cid:1)170(cid:2)W) between the
chitkaPass(eastofAmchitkaIsland);thesepassesare eastern and the central and western Aleutians. There
relatively deep (>400 m) and wide (>100 km). The aredifferencesininterannualandlong-termsurfaceair
western Aleutians lie between Amchitka and Attu Is- temperature patterns such that the eastern Aleutians
land on the eastern side of Kamchatka Strait. As we experienced two regime shifts in the past three dec-
discusslater,thetopographyoftheAleutianArchipe- ades, whereas in the central and western Aleutians
lagostronglyinfluencesbiophysicalprocessesandhence these were much less pronounced (Rodionov et al.,
regionalecosystemfunctionandform. 2005b). The NP index provides a measure of the
strength ofthe Aleutian Low (Trenberth and Hurrell,
Atmospheric features
1994);ithasundergoneabrupt‘regimeshifts’in1976/
Paleoclimate data demonstrated that large regional to 77 and 1988/89. A regime may be defined as a per-
global-scale climate changes have occurred with sistent (decades) state in climate (i.e. the state of
periods from years to decades (e.g. Higgins and Vel- atmosphere and ocean over periods longer than a
linga, 2004). Analyses of lake sediment samples col- season) and biological systems (Beamish et al., 2004).
lected in southwestern Alaska (near the Bering Sea) A regime is thus a quasi-stable ecosystem state that
revealed that variations occurred in climate and can shift with climate change. This has occurred in
ecosystem during the Holocene (Hu et al., 2003). In the NP Ocean, where changes in indices of atmo-
the Aleutians, more recent analyses (Causey et al., spheric and oceanic features (i.e. climate) were con-
2005) substantiate the earlier findings with respect to comitant with changes in biota (e.g. Hare and
variations in climate (alternating periods of warm- Mantua, 2000; Hollowed et al., 2001).
wet and cold-dry conditions) forcing changes in the
Oceanic features
ecosystem, as manifested in changes in marine bird
populations. The oceanic component of the Aleutian ecosystem
Regionalatmosphericcharacteristicsareconnected consists of two major currents, each with their own
to global- and hemispheric-scale phenomena (e.g. water properties, chemistry and biology. Mean north-
NPRB, in press; Stabeno et al., in press). Among the ward transport occurs through the eastern and central
majoratmosphericclimatefeatures(i.e.thoseontime passes (Schumacher and Stabeno, 1998; Stabeno
scales of seasons and longer) influencing the NP and et al.,1999).Waterflowingthroughtheeasternpasses
BeringSea,aretheElNin˜o/SouthernOscillation(e.g. includes the Alaska Coastal Current, connecting the
Overlandet al.,2001),atmospheric-relatedpatternsin Gulf of Alaska and eastern Bering Sea continental
sea surface temperature, such as the Pacific Decadal shelves. Oceanic (Alaskan Stream) waters of the NP
Oscillation and the Victoria Pattern (e.g. Bond et al., flow into the Bering Sea through the central passes.
(cid:1)2005Blackwell Publishing Ltd,Fish. Oceanogr.,14(Suppl. 1),277–291.
Towardsustainable ecosystem services 279
This exchange fuels the rich ecosystem of the eastern birdsmostabundantintheeastern(short-tailedshear-
BeringSea(e.g.BEST,2004;PICES,2004)anditalso waters Puffinus tenuirostris and tufted puffins Fratercula
feedsthebottom-upenergyflowthroughtheAleutian cirrhata) versus the central passes (northern fulmars
ecosystem. This supplement reports significant Fulmarus glacialis and some shearwaters) owing to the
progress to understand the nature of physical differencesinphysicalprocess(Jahnckeet al.,2005).It
phenomena themselves and also on how they influ- appears that the lack of physical features in some for-
ence biological components of this ecosystem. As was agingregions(i.e.asobservedinthedeepercentraland
presentedinthepalaeoecological(Causeyet al.,2005) westernpasses)likelyaffectsthetransferofenergyfrom
and atmospheric climate (Rodionov et al., 2005b) lowertohighertrophiclevels.Notonlydothedeeper
studies,theexaminationofcurrentsindicatesaneast– passeshavelessprimaryproduction,butalsothetransfer
west transition that is centred at Samalga Pass (Ladd of that production to higher trophic levels may be
et al., 2005a). Also, the processes of tidal current constrained(Laddet al.,2005b).
mixing within passes and subsequent re-establishment
Fish and crabs
ofverticalstructureresultinanorth–southtransition;
the northern side of the Aleutian archipelago (par- Although not part of the directed funding, consider-
ticularly in the lee of the islands) is more productive ationsoftheimpactofcommercialfisheriesarecrucial
(Ladd et al., 2005a). Tidal mixing contributes to the toward understanding ecosystem dynamics. We pro-
nutrient flux into the Bering Sea from the shallower videabriefaccountofthecommercialfisheries inthe
eastern passes (Stabeno et al., 2005). The volume Aleutian Archipelago [based on information from the
transport through Amukta Pass appears to be five Stock Assessment and Fishery Evaluation (SAFE)
times greater than previously estimated (Stabeno report (NPFMC, 2004a) unless otherwise noted]. The
et al., 2005). Thus, the contribution of this nutrient- primary groundfish fisheries in the Aleutian Archi-
rich flow through Amukta Pass to formation of the pelago are Pacific ocean perch Sebastes alutus, walleye
Aleutian North Slope Current is far greater than pollock Theragra chalcogramma, Atka mackerel Pleur-
previously thought. Importantly, variations in volume ogrammus monopterygius and Pacific cod Gadus macro-
transportat longer (>1 month)time scales are related cephalus (NRC, 2003). A marked impact of
to the position and strength of the Alaskan Stream commercial fishing occurred in the 1960s and early
(Stabeno et al., 2005). 1970s when the foreign trawl fishery depleted Pacific
Volumetransport,tidalmixing,presenceofoceanic ocean perch stocks, with the greatest landings of
and shelf waters, and fronts all have impacts on the 109 100 metric tonnes (t) in 1965. The current
nutrient–phytoplankton–zooplankton sequence and domestic fishery is managed under a rebuilding plan
highertrophic level dynamics.Nutrient dataand esti- that constrains landings to sustainable levels, such as
mates of the volume transport (Stabeno et al., 2005) 10 331 mt in 2004. Estimates of total Pacific ocean
indicate that flow through Amukta Pass accounts for perch biomass from the 1991–2004 triennial trawl
more than 75% of the total nutrient flux between surveysshowthat,onaverage,45%ofthebiomasswas
UnimakandTanagaPasses(Mordyet al.,2005).These in the western Aleutians; the central and eastern
authorsalsonotethatduetothevigoroustidalmixing,it Aleutians each have (cid:1)27% of the total. Although
appearsthatnewprimaryproductionisinhibitedwithin pollockaretheprincipalfooditemformanyspeciesin
the passes, but substantial blooms occur downstream the eastern Bering Sea food web, including humans
after stratification occurs. A zooplankton community (Livingston, 1995), they are less important in the
consistingofoceanicgeneraexistedinthecentralpas- Aleutian Island ecosystem. A small fishery began in
ses, whereas the eastern passes contained a mixture of the late 1970s, primarily in the eastern Aleutian
oceanicandneriticzooplanktonspecies(Coyle,2005). Islands and over the basin westward to (cid:1)180(cid:2)W
Theinteractionoftidalcurrentswithtopographicfea- (Bowers Ridge); from 1989 to 1998, the fishery was
tures results in fronts, regions with strong horizontal more dispersed along the entire chain. This fishery
gradients ofocean properties that separate well-mixed peaked at 98 604 mt in 1991 and declined thereafter.
and stratified regions (Ladd et al., 2005b). These au- The North Pacific Fishery Management Council
thors noted that depending on feeding strategies (e.g. (NPFMC) applied a precautionary management
picking prey at the surface, subsurface foraging or approach when it closed the fishery after 1998 to
plunge-diving deep feeding), seabird concentrations eliminate a possible impediment to recovery of the
wereassociatedwitheitherfrontsorconvergencezones endangered western stock (west of 144(cid:2)W) of Steller
in the mixed water. As with other elements of the sea lions (Eumetopias jubatus). By legislative fiat,
ecosystem, there was a differentiation in the types of however, a pollock fishery will be opened in the
(cid:1)2005Blackwell Publishing Ltd,Fish. Oceanogr., 14(Suppl.1), 277–291.
280 J.D. Schumacherand G.H.Kruse
Aleutians starting in 2005 (see section, ‘Sustaining fulmars, and tufted puffins are extremely abundant
ecosystem services: improving management’). The species in the Aleutians (Piatt and Springer, 2003).
former foreign fishery for Atka mackerel became an Physical features ofthe ecosystem provide factors that
entirelydomesticfisheryin1990.Itwasthelargest(by affect distribution of seabirds. The interaction of
weight) groundfish fishery in the Aleutian Islands in strong currents with bathymetric features results in
the1990s(NRC,2003);in1996,over100 000 twere zones of vertical currents, mixing and convergences
caught. The biomass distribution among the western, that make island passes attractive foraging regions
centralandeasternAleutiansvariesamongsurveys;in (Ladd et al., 2005b). For instance, whiskered auklets
2004, it was 30%, 42% and 28%, respectively. Steller (Aethia pygmaea) concentrate at sites where there are
sea lion predation was the third largest identifiable strong tidal currents and forage exclusively on
source of Atka mackerel mortality based on estimates zooplankton concentrated in tiderips, swirls, tidal
during 1990–94. Since the early 1990s, Pacific cod pumps and fronts and other areas of strong upwelling
contributed an increasing proportion of the total near islands or offshore reefs (Williams et al., 2003).
commercial catch in the Aleutian Islands. From 2000 The distribution and abundance of auklets in the
and2003,thecatchaveraged34 250 t.Pacificcodare Aleutian Islands has been regulated by the introduct-
the greatest source of mortality of Atka mackerel, ion of non-native Arctic foxes (Alopex lagopus) in the
accounting for nearly 10% more than do Steller sea 18thto20thcenturiesforfurfarming(Williamset al.,
lions and 4% more than commercial fishing. 2003). Whiskered auklets have been designated as a
Commercially exploited crabs also provide an United States Fish and Wildlife Service (USFWS)
important commercial ecosystem service in the Bird of Conservation Concern in the Alaska Region
Aleutian Archipelago. Species harvested include red duetoconcernsoveritslocalizedbreedingdistribution
kingcrab(Paralithodescamtschaticus),goldenkingcrab onBuldirIsland(USFWS,2002).AsnotedbyDragoo
(Lithodes aequispinus), scarlet king crab (L. couesi), et al.(2004),theproductivity(chicksfledgedpernest)
Tannercrab(Chionoecetesbairdi),triangleTannercrab of several key species showed spatial variation, e.g.
(C. angulatus), and grooved Tanner crab (C. tanneri, black-legged kittiwakes (Rissa tridactyla, surface fish-
NPFMC, 2004c). Some of these stocks are not sur- feeders) had high (1.26) productivity on Bogoslof
veyed, and others are only surveyed on a limited basis Island (eastern Aleutians), moderately high (0.8)
so that population trends are not known. Red king productivity on Koniuji Island (central Aleutians),
crab fisheries began in the western Aleutians in the and low productivity (0.07) on Buldir Island (western
early 1960s, collapsed in the early 1970s, and did not Aleutians) in 2002. The percentage of maximum
recover(Orensanzet al.,1998).Redkingcrabharvests number of birds, however, has been steady (1996–
in the eastern Aleutians began in the late 1960s, 2002)at(cid:1)80%onBuldir,whereasithasgonefroman
declined in the late 1970s, increased in 1980–81, and average of (cid:1)90% (1996–98) to <50% (2002) on
collapsed in 1982. The demise of the red king crab Koniuji Island. Likewise, for thick-billed murres (Uria
fisheries throughout Alaska caused disastrous social lomvia), productivity on Buldir Island has been relat-
and economic consequences, which are well docu- ivelyconstantsince1987atameanof(cid:1)0.70,whilein
mented(Wooster,1992).Afterthecollapseofthered the central region (Kasatochi Island) productivity
king crab fisheries, fishermen began to target golden declined rapidly between 1997 and 1998 ((cid:1)0.40 to
king crab in the eastern ((cid:1)22% of the total Alaskan <0.01), and it has remained at that level. Numbers of
catch) and western (70% of the total Alaskan catch) Glaucous-winged gulls (Larus glaucescens, surface fish-
managementareasoftheAleutianIslandsintheearly feeders) have declined significantly at Buldir Island.
1980s. Directed fisheries presently exist for triangle
Mammals
Tanner crab (0.05–0.2 million pounds guideline har-
vest level) in the eastern Aleutian Islands and golden The Aleutian Islands have no native terrestrial
king crab (5.7 million pounds guideline harvest level) mammals west of Umnak Island (Bailey, 1993). Sea
for which harvests are roughly split equally between otter populations in southwestern Alaska and the
the areas east and west of 174(cid:2)W. Aleutians, once the home of more than half of the
world’s sea otters (Enhydra lutris), declined by an
Seabirds average of 58% over 1965–92 (Estes et al., 1998).
In the Aleutian Islands there are 144 bird colonies, Morerecently,datashowthattheAleutianportionof
including three with breeding populations over 1 the southwestern Alaska stock contains 22% of the
million birds and two with over 3 million birds total and is declining, with the greatest decreases
(NPFMC, 2004b). Short-tailed shearwaters, northern occurringinthecentralAleutians(AnglissandLodge,
(cid:1)2005Blackwell Publishing Ltd,Fish. Oceanogr.,14(Suppl. 1),277–291.
Towardsustainable ecosystem services 281
2004). The total uncorrected count for the area in Economic Zone (EEZ),1 the commercial groundfish
2000 was 2442 animals, indicating that sea otter catch off Alaska totalled 2.2 million mt. Pollock
populations had declined 70% between 1992 and accounted for 71% and Pacific cod for 12.1% of the
2000. total landings, and the gross value of the catch after
The Aleutian Archipelago is also home to the primary processing was approximately $1.5 billion
Steller sea lion. In 1960 there were 99 000 in the (F.O.B.Alaska).Byweight,abouthalfthecommercial
region, accounting for 40%of the total western stock; fish and shellfish harvest of the entire United States
by 1989 there had been a decrease of (cid:1)81%, and the occurs in Alaska. At one time, these heavily fished
Aleutians accounted for only 22% of the total (NRC, waters were home to vast populations of marine
2003). Based on counts from 2000 and 2002 (Eber- mammals. Commercial exploitation of ecosystem ser-
hardt et al., in press), population trends inthe central vices began after Vitus Bering’s voyage in 1741, and
Aleutians appear to have leveled off and may be overthenexttwocenturies,thatexploitationbrought
slightly increasing, while trends in the eastern theSteller’sseacow(Hydrodamalisgigas)toextinction
Aleutians have been erratic. Counts in the western and the sea otter, northern fur seal, walrus and bow-
Aleutians continue to decline at (cid:1)10% per year. head whale nearly to extinction (Fay, 1981). In the
Concern over the potential role of commercial fish- case of the Steller sea lion, after a steep (>15% per
eries in the decline provided impetus and funds for a year)populationdeclineinthe1980s,theywerelisted
greatly expanded research programme. A summary of as threatened under the U.S. Endangered Species Act
these results includes: (1) diet studies of Steller sea in 1990 (Ferrero and Fritz, 2002). In 1997, the popu-
lions revealed a strong prevalence of Atka mackerel, lation was split into western (west of 144(cid:2)W) and
pollock, and Pacific cod (all targeted by groundfish eastern (east of 144(cid:2)W) stocks, and the western stock
fisheries);(2) size ranges of fish consumed by sea lions was re-listed as endangered due to a continuing
and those targeted by fisheries overlapped consider- decline, e.g. in non-pups at trend sites between 1990
ably, as did the depths and geographic locations used and2002of4.3%peryear(AnglissandLodge,2004).
by both fisheries and sea lions; (3) while these results The eastern stock remained classified as threatened,
suggested the potential for competition for prey; and despite a steady increase in total population counts
(4) other analyses of the distribution of the Atka since the 1980s. Believing that the fishery competed
mackerel and pollock fisheries also indicated that with the Steller sea lion for prey (groundfish), envi-
there was likelihood they could affect survival and/or ronmental organizations led by Greenpeace chal-
recovery of Steller sea lion populations (Ferrero and lenged the U.S. National Marine Fisheries Service
Fritz, 2002). (NMFS)infederaldistrictcourt.FromApril1998,the
AtkamackerelisamajoriteminthedietofSteller time of filing of the suit, Greenpeace versus National
sea lions in the central and western Aleutian Islands Marine Fisheries Service, until March 2003, the court
(Sinclair and Zeppelin, 2002; Zeppelin et al., 2004). (andJudgeThomasS.Zilly)wastheeffectivemanager
The Atka mackerel fishery used to concentrate in of the NP commons (McBeath, 2004).
several locations, most of which were adjacent to Having the court as ‘manager’ ofthe fisheries,with
Steller sea lion haulouts and rookeries and inside thepotentialthatfisheriesmightbeclosed,concerned
critical habitat. Lowe and Fritz (1996) presented evi- commercial and other interests. Senator Ted Stevens
dence of localized depletion of Atka mackerel based was instrumental in having legislation passed so that
on reductions in catch per unit effort over the course in fiscal year 2001, NOAA received supplemental
of the fishing season. Between 1999 and 2002, regu- funding to augment the scientific bases for manage-
lations were put into effect that reduced the catches mentdecisionsregardingfisheriesandmarinemammal
from critical habitat and addressed the temporal interactions in Alaska. In the Announcement of
compression problem, thus reducing the likelihood of Opportunity for these funds, it was stated that…
creatinglocalizeddepletionsofsealionprey(NPFMC, ‘Thereareseveralpossiblefactorscausingthisdecline.
2004a). One of these factors is commercial fishing in habitat
SOURCE OF FUNDS
1In1976,theUnitedStatesassertedjurisdictionoverfishery
The eastern Bering Sea, Aleutian Islands and Gulf of resources within 200 nautical miles from its shores
Alaska together support the world’s largest ground- (MSFCMA). In 1982, the United Nations Convention on
fish fisheries. In the most recent (2003) economic theLawoftheSeacreatedEEZsextendinggenerallyoutto
assessment (Hiatt et al., 2004) of the U.S. Exclusive 200nautical miles fromthe shores ofall coastal states.
(cid:1)2005Blackwell Publishing Ltd,Fish. Oceanogr., 14(Suppl.1), 277–291.
282 J.D. Schumacherand G.H.Kruse
critical to the Steller sea lion, thought to cause a species and the environments in which they live.
harmful reduction in Steller sea lion prey availability. Applying this principle will require defining relevant
To determine if other factors might be important in geographic management areas based on ecosystem,
the decline of the western Steller sea lion population, rather than political, boundaries.’
NOAA was directed to conduct research focused on Thepresentsurgeofinterestinthehealthofmarine
two of the other hypothesized factors, namely impacts ecosystem services needs to be put into action. The
of ocean climate regime shifts, and changes in pred- path toward attaining management that follows eco-
ator/prey relationships’ (e.g. http://www.pmel.noaa.- system-based principles and policies (Fluharty et al.,
gov/steller/ssl_goals.shtml, June 2005). 1999) requires a combination of research to improve
the‘bestscientificinformationavailable’standard(e.g.
NRC, 2004a), as well as the development and appli-
EMPHASIS ON SUSTAINABILITY OF
cation of improved management strategies. To attain
ECOSYSTEM SERVICES
sustainable ecosystem services, we must develop a
Recognizing the necessity of maintaining ecosystem better understanding of how natural forcing (e.g. cli-
services in the context of a broader (e.g. including matechange,diseaseepidemics)andhumaninfluences
quality of life) set of management objectives rather (e.g. fisheries harvest, direct and indirect fishing im-
than the traditional sole focus on commercial fishery pacts to habitat, hazardous material spills) affect eco-
‘resources’isconsistentwiththeintentandwordingof system function and structure. Science is a necessary,
theobjectivesoftheNOAAFisheries(a.k.a.National but not sufficient basis for environmental decision-
Marine Fisheries Service, NMFS). According to making (Bryant, 2005) that can lead to sustainability;
NMFS (2005), adaptive management strategies (e.g. Walters, 1996)
that take into account ecological, economic and
As a steward, NOAA Fisheries conserves, protects,
sociological factorsalso need tobe employed.
and manages living marine resources in a way that
ensures their continuation as functioning compo-
Resilience and sustainability
nents of marine ecosystems, affords economic
Ecosystemsexistinquasi-stablestatesinwhichforcing
opportunities, and enhances the quality of life for
or ‘shocks’ can shift them into another regime of
the American public.
behaviour, i.e. to another quasi-stable state (Holling,
Ecosystem-based management and sustainability 1973). Resilience is measured by the magnitude of
are also objectives of the NPFMC (Witherell et al., disturbance that can be absorbed before the system
2000; NPFMC, 2002), which was established by the redefines its structure by changing the variables and
Magnuson Fishery Conservation and Management processes that control behaviour (Gunderson et al.,
Act of 1976 (and revised in 1996 as the Magnuson- 2002). Ecosystems experiencing diminished resilience
Stevens Fishery Conservation and Management Act, (e.g. due to excessive human pressure on a resource),
MSFCMA). Recent reports on the status of our na- which are then subjected to a shock (e.g. disease, cli-
tion’s oceans also support ecosystem-based fisheries matechange),canbepushedbeyondacriticalthresh-
management with the goal of sustainable services and old (NRC, 2004b) and shifted into a new, potentially
ecosystem-wide health (POC, 2003; USCOP, 2004). less desirable state with a reduced capacity for life-
The Pew Oceans Commission’s (hereafter ‘the Com- supportingservicesforsociety(Schefferet al.,2001).
mission’) report emphasizes the importance of the
connection between healthy ecosystems and com-
SUSTAINING ECOSYSTEM SERVICES:
mercial interests in its Executive Summary:
RESEARCH CHALLENGES
The fundamental conclusion of the Pew Oceans
While much has been elucidated in this supplement,
Commission is that this nation needs to ensure
our present knowledge of the Aleutian ecosystem
healthy, productive, and resilient marine ecosys-
functionandstructureisstillrudimentaryandneedsto
temsforpresentandfuturegenerations.Inthelong
be improved. Improvement is necessary if we are to
term, economic sustainability depends on ecologi-
have a chance to distinguish natural from human
cal sustainability.
forcing, thereby putting boundaries on the issues that
TheUSCOP(2004)identifiedaguidingprinciplethat managers must address. Sustainable use of ecosystem
‘… U.S. ocean and coastal resources should be man- services is unlikely without a more comprehensive
aged to reflect the relationships among all ecosystem understandingofthecapacityofecosystemstoprovide
components, including humans and non-human thoseservices(GundersonandHolling,2002)andthe
(cid:1)2005Blackwell Publishing Ltd,Fish. Oceanogr.,14(Suppl. 1),277–291.
Towardsustainable ecosystem services 283
development of ecologically sound management poli- stock assessments for more than a decade, the devel-
cies. The overarching question is: what is the resili- opmentofsuchmodelsforthe AleutianIslandsbegan
ence of the Aleutian ecosystem? in 2003 only (Barbeaux et al., 2003). The assessment
scientists are well aware of potential pitfalls of this
Limited knowledge of biota
assessment,including:(1)theassumptionthatpollock
A basic hurdle toward answering this question is the are homogenously available during the ‘depletion’
present limited state of knowledge, particularly of period can confound results; (2) paucity and inconsis-
biota. The limited state of knowledge is clearly illus- tencyofavailabledata;and(3)substantialuncertainty
trated by the fact that huge changes in ecosystem inthestockstructure.Thus,fisherymanagementofone
components (e.g. marine mammals, crabs) have ofthemostimportantandnumerousfishspeciesinthe
occurred in the Aleutian Islands region and, with just Aleutian Islands region is severely hampered by large
a few exceptions (e.g. Steller’s sea cow), their causes uncertainty. Development of ecosystem models (e.g.
remain equivocal. Cold-water corals provide another Aydin, 2002) provides some promise for a more com-
example of both the limited nature of our knowledge plete understanding of the ecosystem, but for model
and uncertain management actions in light of this simulations to approach reality, improved and expan-
reality. It is only in the last few years that the extent ded data collection isrequired.
and potential importance of cold-water corals in the
Aleutian Islands has been recognized. The Aleutian Limited knowledge of the impact of climate change
Islands may harbour the highest diversity and abun- Research issues also exist regarding the phys-
dance of cold-water corals in the world, and these ical components of the ecosystem, namely how the
communities likely provide important habitat for a atmospheric and oceanic components of the NP
variety of fish and invertebrates (Heifetz et al., 2005). ecosystem will respond to global climate change (e.g.
The NPFMC recognized the need to protect the coral Hollowed, 1996; Schumacher and Alexander, 1999;
gardens because of their uniqueness and contribution Schumacher et al., 2003). Two potential changes
to biodiversity and fish habitat. In February 2005, to with relevance to the Aleutian Archipelago are:
protect Essential Fish Habitat, the Council voted to (1) storms are expected to become less severe but
ban bottom-trawling everywhere in the Aleutians, more frequent and be warmer and wetter than pre-
except in the relatively small areas where commercial sent, and (2) the volume flux of the Alaskan Stream
fishingalreadyexists(minusafewcoral-richareasthat into the Bering Sea will decrease. At the same time,
already are off limits). Both fishermen and environ- the Alaska Coastal Current will likely increase due to
mental groups applauded this act by the Council enhanced precipitation in the Gulf of Alaska and
(Welch, 2005). It must be noted, however, that adjacent coastal areas. The warmer, wetter scenario
longlines and crab pots also damage corals and other has occurred before and had consequences on biota
benthic habitats, and these methods have not been (Hu et al., 2003; Causey et al., 2005). Further, as
restricted, except in a small subset of areas designated surface air temperatures rise, physiological rates of
as Habitats of Particular Concern, where all bottom biota will also be affected. The change in volume
contact gear is banned. flux, and associated nutrients and plankton, has a
Stock assessment provides yet another example of direct influence on primary and secondary production
our limited knowledge and the potential resultant and possibly on the transfer of energy to higher
pitfalls.The mostuseful and essential elements ofany trophic levels. As shelf and oceanic waters become
management scheme or examination of ecosystem warmer, the flora and fauna will likely also change to
dynamics are the estimates of species (e.g. fish, shell- a more temperate species composition. The increase
fish, marine mammals and birds) abundance. This in water temperatures throughout the upper 250 m of
information is provided by routine trawl and hydro- the water column has already been accompanied by a
acoustic surveys and observer data collected on both decrease in salinity (Royer, 2005). In this supplement
agency-operated and chartered fishing vessels, as well (Stabeno et al., 2005), the strength of the Alaskan
ascountsofseabirdsandmarinemammalsbyfieldcrew Stream flow through Amukta Pass was shown to be a
deployments.Foraparticularexample,intheAleutian function of the stream’s location and strength. How
Islandecosystemthree‘management’stocksofpollock will these characteristics change with the changing
havebeenidentified,whichprobablyhavesomedegree atmospheric climate? We know that eddies can block
of genetic exchange (NPFMC, 2004a). Although pol- or even reverse northward flow through the passes
lockstocksintheGulfofAlaskaandBeringSeahave (Reed and Stabeno, 1993). If the strength of the
beenassessedbycomplexmathematicalage-structured Alaskan stream decreases (Hollowed, 1996), will
(cid:1)2005Blackwell Publishing Ltd,Fish. Oceanogr., 14(Suppl.1), 277–291.
284 J.D. Schumacherand G.H.Kruse
eddies become more frequent and severely impact resolveongoingandfutureecosystemissuesrequiresthe
volume transport through the Aleutian passes? melding of well-focused research and expanding some
of the present management policies, especially those
Solution: increased funding
that are precautionary in the face of uncertainty. In
How do we best address the questions presented addition,strategiesneedtobedevelopedforimproving
above? One part of the answer is to increase funding the use of the best scientific information by manage-
for integrated (both biotic and abiotic) ecosystem ment (NRC, 2004a). Even with such strategies, how-
research. As noted in recent ocean commission ever, value and policy judgments must also be made.
reports,managementdecisionsneedtobebasedonthe Managementneedstoconsiderexploringnewapproa-
bestpossiblescience.Thatbodyofknowledgeispoorly chesthatcouldmoreeffectivelyincorporateestablished
funded at present: ecosystem-based principles and policies (e.g. Fluharty
et al.,1999;Witherellet al.,2000;NPFMC,2002).
The nation must increase investment in ocean
scienceandresearch,particularlybroaderecological
Balancing economic with ecosystem considerations
monitoring programmes and investigations. To
In a recent action by the U.S. Congress (in an
support this endeavour, the Commission recom-
attachment to an appropriations bill), the NPFMC
mends that Congress at least double funding
(NPFMC News, 2004) was instructed to apportion a
for basic ocean science to 1.5 billion dollars
quota(upto40 000 mt)totheAleutCorporation(an
annually... (POC, 2003)
Alaskan Native organization) for a directed pollock
The USCOP (2004) had a similar recommendation fishery in the Aleutian Islands. (The pollock fishery
(#25–1):‘Congressshoulddoublethefederaloceanand had been closed by the NPFMC since the end of the
coastalresearchbudgetoverthenextfiveyears,fromthe 1998seasonasaprecautionarymeasurewithrespectto
2004levelofapproximately$650millionto$1.3billion Steller sea lions.) The intent of the legislation is to
per year.’ Environmental organizations have an estab- provide for economic development in the community
lished track record of using email campaigns to lobby of Adak and through the Aleut Corporation. The
legislators and thereby impact decision-making. This reestablishment of Aleut presence in the Aleutian
methodandotherscouldbeusedtosupportincreasesin Archipelago has been an ongoing process; the
funding for ecosystem monitoring and research. The Departmentofthe Interiortransferred 47 291acres of
National Research Council (NRC, 2004b) and North land on Adak Island, including the former Adak
Pacific Research Board (NPRB) have identified integ- Naval Air Facility, to the Aleut Corporation. Adak is
ratedecosystemstudiesasacentraltheme;NPRBpre- in the middle of one of the world’s richest fishing
sentsonefortheAleutians(NPRB,2005).TheAlaska regions and existing facilities make it economically
Ocean Observing System (AOOS: http://www.aoo- possible to handle primary processing on the fishing
s.org,June2005)identifiedpulsepointsformonitoring grounds and deliver higher quality seafood to
in Alaskan waters, including volume transport and demanding European consumers (http://www.alaska.
waterpropertiesinAmuktaPass. net/(cid:1)vwadak/, June 2005). Currently cod, crab, hali-
but and other groundfish are being processed.
In response to a request from the Aleut Corpora-
SUSTAINING ECOSYSTEM SERVICES:
tion, the State of Alaska is currently exploring open-
IMPROVING MANAGEMENT
ing a small-boat (<60 feet) pollock fishery in state
ThecurrentstateoftheAleutianArchipelagoecosys- waters (£3 miles from shore), which could impact
tem is a result of its history that includes substantial recovery of Steller sea lion populations. This high-
human and natural forcings that operate on various lights the issue of mixed-agency management of an
time and space scales. Overfishing of Pacific ocean ecosystem – a state fishery within areas closed by
perch in the 1960s, the collapse of the red king crab federal agencies – as fish do not obey political
fisheries,thedecliningpopulationofrougheyerockfish boundaries.Ontheotherhand,suchafisheryprovides
(Sebastes aleutianus,(cid:1)50%declineinestimatesofbio- an opportunity to conduct an adaptive management
mass between 1980 and 2005, NPFMC, 2004a) all experimentcomparingopenversusclosedfishingareas
demonstrate that such forcings have impacted main- around rookeries to estimate the impact of fishing on
tenance of ecosystem services. The intersection of Stellersealions(e.g.Bowenet al.,2001;NRC,2003).
naturalandhumanforcingaffectstheresilienceofthe The objective of such an experiment would be to
Aleutian Islands ecosystem. Will ecosystem services determine whether commercial fishing (e.g. reduction
remain as available as they are now? The strategy to in local fish abundance, dispersion of fish schools) is
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Towardsustainable ecosystem services 285
energetically costly to foraging Steller sea lions. The routine oil and gas development and transport have
timing and location of fisheries relative to foraging had a direct impact on the southwestern Alaska sea
patterns of marine mammals may prove to be a more otter stock. Other potential threats to sea otter pop-
relevant management concern than total removals. ulationsincludenaturalfluctuations,suchasdiseaseor
Sinclair and Zeppelin (2002) identified another predation, and indirect effects of other human activ-
potential effect of fishing by demonstrating that, for ities. Disease, starvation and contaminants are not
thewesternstockofStellersealions,dietdiversitywas presently indicated in the Aleutians, however further
highest where the populationtrendswere moststable. evaluation of these factors is warranted along with
In addition to identifying data and monitoring additionalinvestigationofthepredationhypothesisto
requirements to include in adaptive management better elucidate the cause(s)of the decline. Seaotters
options, the NRC (2003) recommended several such play an important role in maintaining the coastal
alternatives, identifying that the one that offered the ecosystems they inhabit. In nearshore kelp beds, sea
greatest benefits with regard to increasing under- otters function as keystone species, strongly influen-
standing of the effects of fisheries on Steller sea lions cing ecosystem functions. In the Aleutian Archipel-
was to use replicated open and closed rookeries to ago, sea urchins are a dominant herbivore and an
experimentally evaluate localized fishing impact. important food source for sea otters (Estes et al.,
Naturalforcing,throughanarrayofprocesses,hasalso 1998). In areas of reduced sea otter abundance, sea
beenhypothesizedastheprimaryfactorinthechanges urchinpopulationsarereleasedfromthecontrolofsea
in the Steller population. The NRC (2003) suggested otterpredation,andurchinsovergrazethekelpforests,
that bottom-up processes invoking nutritional stress creating so-called urchin barrens. As detached kelp is
are unlikely to be the primary threat to recovery, swept away, fish and invertebrates lose protective
leaving direct mortality by predation as the mostly cover,andanimportantsourceoforganicsislostfrom
likely candidate. If a state fishery is developed for the nearshore areas (Estes et al., 1998).
pollockintheAleutians,itisimperativetoestablisha
research and monitoring programme so as not to Threats to seabirds
squander this potential adaptive management oppor- Seabird foraging success may be key to overall health
tunity to shed light on the question of potential of species and colonies. Among the primary factors
competition between the fishery and Steller sea lions. affectingfoodavailabilityare:(1)spatialandtemporal
changes in forage fish availability due to ecosystem
Declines of sea otters
effects, (2) commercial fishery removals of forage
PopulationstudiesintheAleutianIslandsindicatethat fish, either through directed catch or bycatch,
observeddeclinesinseaotterabundancearetheresult (3) enhancements to forage fish stock and availability
ofincreasedadultmortality(AnglissandLodge,2004). due to commercial fishery removal of predators, and
One current theory proposes that predation by tran- (4) provisioning of food to seabirds through discard
sient killer whales may be a leading cause of the pop- andoffal from commercial fisheries(NPFMC,2004b).
ulation decline (Estes et al., 1998). Estes et al. (1998) Localseabirdreproductionwillfailiffoodsuppliesare
support thiswith observationsofasignificant increase reduced below the amount needed to generate and
in killer whale attacks on sea otters during the 1990s, incubate eggs, or if the specific species or size of prey
scarcity of beach-cast otter carcasses, and markedly needed to feed chicks is unavailable (Hunt et al.,
lowermortalityratesforseaottersinashelteredlagoon 1996). Other fishery interactions occur through inci-
(where killer whales cannot go) compared with an dentalcatchofseabirdsinlonglineandtrawlfisheries.
adjacent exposed bay. The NRC (2003) notes that a In addition, the introduction of invasive species to
switch of fewer than four killer whales to feeding the Aleutians has greatly affected bird populations
exclusively on sea otters could account for the addi- through predation of eggs and young chicks. Rats
tionalannualmortalityinthecentralAleutiansduring invaded several islands as recently as World War II,
the rapiddecline ofthe sea otter population. foxes were stocked (for fur ranching) on islands with
Angliss and Lodge (2004) noted that sea otter birdcoloniesaslateas1945,andcaribouwerereleased
abundance in southwestern Alaska is not likely to be on Adak Island in the late 1950s (Ebbert and Byrd,
significantly affected by commercial fishery interac- 2002). Although most rat and mouse introductions
tionsatpresent;thereisvirtuallynofishingactivityfor wereaccidental,otherrodents(deermice,arcticground
their primary invertebrate prey in the region. While squirrels,volesandshrews)wereintentionallystocked
thecatastrophicreleaseofoilhasthepotentialtotake byfoxranchersasalternateprey(http://alaska.fws.gov/
large numbers of sea otters, there is no evidence that nwr/akmar/whatwedo/bioprojects/restorebiodiversity/
(cid:1)2005Blackwell Publishing Ltd,Fish. Oceanogr., 14(Suppl.1), 277–291.
286 J.D. Schumacherand G.H.Kruse
historical.htm,June2005).Ratsextirpatemostspecies knowledge (i.e. uncertainty) is necessary for man-
of burrow-nesting seabirds, and they probably reduce agement. As Goodman et al. (2002) noted, given
populations of shorebirds and other ground-nesting scientific uncertainty, there is merit in approaching
species. The formerly endangered Aleutian Canada ecosystem management in the spirit of cautious
goose provides an example. Listed as endangered in experimentation. Further, they asserted that embra-
1967 because of predation by Arctic foxes, these birds cinguncertaintyandavoidingfalseprecisioninfishery
wereparticularlyvulnerabletosuchanunprecedented management may require us to forgo the hope of
land predator (Bailey, 1993). Removal of foxes, precise and finely tuned management plans, opting
reintroduction of the geese, and protection of many instead for a series of indicators that can be broadly
breeding locations reestablished the Aleutian popula- categorized. Indicators or reference points are specific
tionsoftheAleutiangeese,aremarkablesuccessstory valuesofmeasurablepropertiesofsystems–ecological,
intheAleutians. social, or economic – used as benchmarks for man-
agement and scientific advice. Ecosystems are com-
Contaminants and shipping
plex,adaptivesystemsthatrequireflexiblegovernance
The Aleutian ecosystem faces other challenges from withtheabilitytorespondtoenvironmentalfeedback
human forcing. Studies show that sea otters and bald (Olsson et al., 2004). So, the institutional and organ-
eagleeggsfromthewesternAleutianscarrypotentially izational landscape should be approached as carefully
harmful levels of DDT and other contaminants (Estes as the biophysical if management is to successfully
et al., 1997). Although the researchers cannot pin- attain reference points and standards. In their syn-
point the sources of the pollutants, their distribution thesis of adaptive management techniques, Sabine
patternsyieldsomeclues.PCBsmaycomefromformer et al.(2004)concludedthatthebestoutcomesrequire
military activity on some of the islands; the DDT a rigorous and formalized approached to planning,
could be windborne or waterborne contamination collaboration, modeling (based on appropriate mon-
from agricultural use in Asia. With increasing indus- itoring for inputs) and evaluation. Finally, simulating
trialization in China, further impacts (e.g. acid rain potential outcomes (i.e. developing a set of narratives
and other pollutants) are likely to occur in the Aleu- of most likely scenarios) of an adaptive management
tians.Finally,UnimakPassisonthegreatcircleroute cycle in the presence of existing uncertainty can help
between the western U.S. and Canada and the Asian identify strategies that are mostlikely to succeed with
portion of the Pacific Rim, so it is a frequently used respect to clearly stated goals. As one concrete
shipping traffic lane. Thus, accidents will occur, such example,iftheStateofAlaskaopensapollockfishery
as the M/V Selendang Ayu, which ran aground and within State waters, then the opportunity would exist
spilled hundreds of thousands of gallons of oil near to apply this iterative process to the question of how
UnalaskaIslandbetweenSkanBayandSprayCapein fishinginthevicinityofarookeryimpactsmortalityof
2004.Thisregionisespeciallyvulnerable,asitishome Steller sea lions in the Aleutians.
tomanyspeciesoffish,marinemammals,andseabirds,
Integrative management – a tool for attaining sustainable
including several species of special concern, such as
ecosystem services
theSteller’seider(threatened),seaotters(threatened)
and Steller sea lions (endangered). The Ecosystem Principles Advisory Panel to Congress
(Fluharty et al., 1999) recognized that ecosystems are
likely to have thresholds which, when exceeded, may
TOOLS FOR SUSTAINABLE ECOSYSTEM
cause the system to shift to a new, potentially irre-
MANAGEMENT
versible state. Defining these levels for ecosystems,
Adaptive management – a tool suited to the task however,ismoredifficultthanforsinglespeciesdueto
the complex interactions and greater uncertainties
Goals of adaptive management are to improve man-
associated with larger numbers of parameters, and the
agement by ‘learning by doing’ and to understand the
impactofincompleteknowledge(Sabineet al.,2004). ability to predict ecosystem behaviour is limited. This
This approach is particularly relevant to managing suggests that traditional reductionist disciplinary sci-
ence andexpertpredictions, the basis for much ofthe
ecosystem services. ‘Learning by doing’ is an appro-
advice given to managers, have limited applicability
priate approach given the inherent complexity of
(Kay et al., 1999).
ecosystem function and dynamics. Our knowledge of
Better results may be obtained through a more
the Aleutian Islands ecosystem is rudimentary at
integrative ecosystems approach. The heart of this
best. Understanding the consequences of incomplete
(cid:1)2005Blackwell Publishing Ltd,Fish. Oceanogr.,14(Suppl. 1),277–291.