A. Status of the Spectacled Eider - U.S. Fish and Wildlife Service

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helicopter surveys in the Prudhoe Bay region, expanded to the entire arctic coastal plain yielded an uncorrected estimate of 16,000 total birds in 1993; this is an underestimate of total birds because the density of Spectacled Eiders is lower in Prudhoe Bay than in other areas of the arctic coastal plain (TERA 1993). Aerial surveys of the eider’s entire current breeding range along the arctic coast of eastern Russia were conducted in late June 1993 and 1994. Combining data from these surveys between the Kolyma River and Kolychin Bay (1993)and-Kolyma and Lena River deltas (1994) suggests that there may be > 140,000 birds in AR (Hodges and Eldridge 1994, 1995). Life History and Ecology Life history characteristics include survivorship, fecundity, age at first reproduction, frequency of reproduction, and lifespan. These traits vary with changes in populations and their environments. A suite oflife history characteristics can be referred to as a life history strategy. Important influences on life history strategies of northern sea ducks are the extreme environmental conditions in both breeding and non-breeding environments and the high degree ofvariability both within and between these environments. The timing, length and climate ofthe breeding season varies from year to year in northern regions. Life cycles ofnorthern marine birds (timing of arrival on breeding grounds, reproductive cycle, and migration) are directly affected by seasonal changes in the hydrological and hydrobiological conditions (Uspenskii 1984). The timing ofsnow melt, and the break up ofseasonal ice in marine waters along migration routes and in freshwater ponds on breeding grounds can vary by several weeks from year to year. This increases the potential for delayed availability of nesting habitat, reduced clutch sizes, and non-breeding (Barry 1960, 1967; Cooch 1965; Ryder 1967; Kistchinski and Flint 1974). Sea ducks must be adapted to life at sea and on land, and to both marine and freshwater environments. Different strategies for foraging, locomotion, water balance, and thermoregulation are required in each ofthese environments. Furthermore, life in northern regions requires specialized adaptations to extreme temperatures and to large variations in weather and temperature. For example, a northern sea duck must be able to maintain its body temperature in temperatures from 600F) during the summer. Basic life history information is lacking for many ofthe sea duck species. The available information indicates that sea ducks are long-lived, annual adult survival is high (in a healthy population), annual recruitment to breeding age is low, annual breeding rates and success is variable, clutch size is small, and sexual maturity is deferred (Goudie et al. 1994). Ecologists refer to species with this suite ofcharacteristics as “K-selected” (Wilson 1980). This type of strategy minimizes the importance ofannual investment in reproduction and maximizes the importance ofannual survival; population stability is dependent on high adult survival and a few successful years of reproduction (ibid.). 18
Summer in northern regions can be highly productive because oflong hours ofsunlight. Although the length ofthe arctic summer can vary from year to year, it is relatively short. Ducklings must be ready to leave the breeding grounds, transition to the marine environment, and undertake migrations by the end ofthis short season. Ifnest initiation is late in a given year because of climatic conditions, the likelihood ofreproductive success is low. Therefore, there is a greater likelihood offailed breeding occurring in any given year, as a result ofdelayed onset ofbreeding, than there would be at more southeriy latitudes. A life history strategy that favors adult survival and a longer lifespan (“K-selected”) rather than high productivity and a short lifespan (“r-selected strategy”) may result in greater total lifetime productivity (Goudie et al. 1994). Management for recovery ofdeclining eider populations is difficult because K-selected life history waits may limit the rate ofrecovery. Small clutch size, low rates ofannual reproduction and low annual recruitment to breeding population may result in slow population growth even in the absence ofthreats. Information about life history characteristics can guide researchers in testing hypotheses about causes ofpopulation declines. Our knowledge of the life history and ecology of the Spectacled Eider comes from anecdotal accounts in early years (Turner 1886; Nelson 1887; Dufresne 1924; Murie 1924; Conover 1926; Gillham 1941, 1942; Brandt 1943; Bailey 1948; Johnsgard 1964a; Portenko 1972) and formal studies in recent years (Dau 1974; Kistchinski and Flint 1974; Mickelson 1975; Harwood and Moran 1991; Kondratev and Zadorina 1992; Warnock and Troy 1992; Harwood and Moran 1993; TERA 1993; Anderson and Cooper 1994; Moran and Harwood 1994; Smith et al. 1994; Anderson et al. 1995; Johnson 1995; Moran 1995; TERA 1995; J. B. Grand, pers. comm.). On the YKD, Spectacled Eiders are primarily dispersed nesters, often associated with other waterbird species (Dau 1974; Strang 1976). Johnsgard (1964a), however, found Spectacled Eider nests clumped at some sites on the YKD, suggesting a degree of “incipient colonialism.” Nests are susceptible to both avian and mammalian predation, which varies both annually and geographically on the basis of predator and prey densities (Kistchinski and Flint 1974; C. Harwood, pers. comm.; T. Moran, pers. comm.; J.B. Grand, pers. comm.). On the Indigirka and Chaun River deltas in AR, most Spectacled Eiders nest semi-colonially in association with gull or tern colonies; they nest less often as dispersed single birds (Kistchinski and Flint 1974; Kondratev and Zadorina 1992). As on the YKD, they nest near water and are vulnerable to predation (Kistchinski and Flint 1974). On the NS, Spectacled Eiders are dispersed, low-density nesters (Derksen et al. 1981; Warnock and Troy 1992) and are not associated with gull or tern colonies. At least some female Spectacled Eiders exhibit strong fidelity for nesting areas (Dau 1974). On the YKD, females nested within 1.5 km from their previous nest sites (Dau 1974; Harwood and Moran 1993; Moran and Harwood 1994; Moran 1995; Moran 1996). If characteristic, this tendency has important implications for protecting and recovering specific 19
Page 2 and 3: SPECTACLED EIDER RECOVERY PLAN Team
Page 4 and 5: LITERATURE CITATION U.S. Fish and W
Page 6 and 7: EXECUTIVE SUMMARY OF THE RECOVERY P
Page 8 and 9: TABLE OF CONTENTS DISCLAIMER PAGE 1
Page 10 and 11: LIST OF FIGURES Figure 1. Breeding
Page 12 and 13: A. Status of the Spectacled Eider R
Page 14 and 15: ) a) j~ 25000 0 2 220000 C ~15000 ~
Page 16 and 17: B. Causes for Decline and Obstacles
Page 18 and 19: Increasing interest in avicultural
Page 20 and 21: Other conservation measures include
Page 22 and 23: D. Natural History of the Spectacle
Page 24 and 25: Figure 4. Yukon-Kuskokwim Delta loc
Page 26 and 27: DEL?A RUSSIA SPECTACLED EIDER RANGE
Page 30 and 31: geographic populations, because imm
Page 32 and 33: Figure 8. Study sites and land stat
Page 34 and 35: their diseases (e.g., Schiller 1954
Page 36 and 37: E. Distinct Population Segments The
Page 38 and 39: A final consideration involves info
Page 40 and 41: Trend data are analyzed to inform w
Page 42 and 43: Figure 10. A hypothetical posterior
Page 44 and 45: thresholds are not “magic numbers
Page 46 and 47: Criteria for Reclassifying from Thr
Page 48 and 49: Criteria for Delisting from Threate
Page 50 and 51: The final aspect ofSpectacled Eider
Page 52 and 53: concordance in their descriptions o
Page 54 and 55: data on both levels and effects oft
Page 56 and 57: implicated. In the absence of histo
Page 58 and 59: . - currently small size of the YKD
Page 60 and 61: implementation of the Memoranda ofA
Page 62 and 63: . take of Spectacled Eiders. In add
Page 64 and 65: . AlS. Produce a handbook summarizi
Page 66 and 67: . Bl.4. 1.3. Develop visibility cor
Page 68 and 69: B2. 1.1. Implement YKD satellite tr
Page 70 and 71: . Appendix Ill). Since epidermal ag
Page 72 and 73: . feasible if post-fledging staging
Page 74 and 75: presumed that their activities have
Page 76 and 77: contaminants within Spectacled Eide
Page 78 and 79:
limited ability to withstand additi
Page 80 and 81:
surface after a year and is no long
Page 82 and 83:
. The reproductive stages (eggs, yo
Page 84 and 85:
is inadequate to sustain “normal
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___________ 1967. The geese of the
Page 88 and 89:
Dementev, G.P., and N.A. Gladkov (e
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___________ 1 964a. Observations on
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Nelson, E.W: 1887. Report upon natu
Page 94 and 95:
________ P.R. Wade, R.A. Stehn, and
Page 96 and 97:
Robert M. Platte, Migratory Bird Ma
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KEY Task Duration and Costs TBD - T
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TASK 324.2 I 12.4.1 .2 PRIOR- — 2
Page 102 and 103:
TASK I — [37 E12 EI.3 fTYU —PRI
Page 104 and 105:
TASK PRIOR- Dj ITYU — — A12.3 2
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— TASK U — 135.2 PRIOR- TASK DE
Page 108 and 109:
TASK U PRIOR- ITY U TASK DESCRIPTIO
Page 110 and 111:
TASK PRIOR. U — DS.3 3 TASK DESCR
Page 112 and 113:
The final risk factor is the effect
Page 114 and 115:
This PVA will treat two population
Page 116 and 117:
Both aerial surveys are conducted a
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0.2 0.15 -j i 4 0.1 0 -I 0.05 0.08
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emaining before the population reac
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) critical population size; and (2)
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40%. The population growth rate cri
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Table 1-2. Results of simulation wh
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Hilborn, R. and C.J. Walters. 1992.
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APPENDIX II TECHNICAL DETAILS OF TH
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The likelihood function for the par
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initial sample. Then the O~ were re
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LU ~0.8 z -J ~0.6 I-ET1 w107 480 m1
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LITERATURE CITED APPENDIX LI De la
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where x = age. The fertility rate i
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of older females: (1) older females
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RESULTS Solutions for single cause
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0.1 0.08 ~0.06 4 0 0.04 0. 0.02 0 0
Page 148 and 149:
growth rate. Perhaps this can be mo
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decline, by far the fastest way to
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LITERATURE CITED APPENDIX In Bailli
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APPENDIX IV SPECTACLED EIDER RECOVE
Page 156 and 157:
APPENDIX V COMMENTS RECEIVED ON DRA
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A. Status of the Spectacled Eider - U.S. Fish and Wildlife Service

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