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

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D. Natural History of the Spectacled Eider Nomenclature and Description Sea ducks, waterfowl that spend at least part oftheir lives at sea, are a subgroup ofthe Subfamily Anatinae, Family Anatidae. Within the subfamily, taxonomists group the waterfowl species into tribes, but while Delacour and Mayr (1945) originally placed the eiders (Tribe Somaterini) in a separate tribe from other sea ducks (Tribe Mergini), Johnsgard (1960) and others have grouped them togetherunder Tribe Mergini. Many species ofMergini spend part or all oftheir lives in northern (arctic and subarctic) regions; these include King Eiders (Somateria spectabilis), Common Eiders (Somateria moiissima), Spectacled Eiders (Somaterzafischeri), and Steller’s Eiders (Polysticta stelleri). In Alaska, all four eider species breed along the arctic coastal plain or along the coast ofwestern Alaska and migrate south to wintering areas in the Bering Sea, Aleutian Islands and GulfofAlaska. The Spectacled Eider, a large-bodied sea duck, is one of three species in the genus Somatena. Originally, Common, King, and Spectacled Eiders were placed in three monotypic genera (Brandt 1847) before their close affinities resulted in their current placement in Somateria (Humphrey 1958; Johnsgard 19Mb; AOU 1983). The male Spectacled Eider has a green crown and nape with a long, sloping forehead, large and distinctive white eye patches, a charcoal-colored chest, and a white back (Palmer 1976). Body plumage of the male Spectacled Eider most closely resembles that of the larger Common Eider. Females of all three Somateria species have similar body plumage, with only slight differences in head coloration and shape. Juvenile and adult female Spectacled Eiders are barred and mottled brown with indistinct eye patches. The iris of both sexes is blue, and the bills of adult males and females are orange and bluish-grey, respectively. Distribution and Abundance Historically, Spectacled Eiders nested discontinuously from the Nushagak Peninsula of southwestern Alaska north to Barrow and east nearly to the Yukon Territory of Canada (Phillips 1922-1926; Bent 1925; Bailey 1948; Dau and Kistchinski 1977; Derksen et al. 1981; Gamer and Reynolds 1986; Johnson and Herter 1989) (Figure 1). They also have nested on St. Lawrence Island (Fay 1961). Along the arctic coast of Russia, Spectacled Eiders nested from the northern side of’the Chukotsk Peninsula west to the Lena River Delta and the Novosibirski Islands (Buturlin 1910; Dementev and Gladkov 1952; Portenko 1972; Kistchinski 1973). Today, primary nesting grounds of the Spectacled Eider are the YKD (Figure 4) and the NS 12
(Cape Simpson to the Sagavanirktok River) of Alaska (Figure 5), and in the Chaun Gulf and on the Kolyma, Indigirka, and Yana river deltas of AR (Figure 6). Breeding Spectacled Eiders were formerly common in small patches of suitable habitat in northwestern Alaska from Norton Sound to Kotzebue Sound (Nelson 1887; Bent 1925; Bailey 1948), where they now are rare or absent (Kessel 1989). Local residents report they can still be found nesting on St. Lawrence Island (J. Cochrane, pers. comm.) (Figure 1). The distribution of Spectacled Eiders during the 8-to-l0-month non-breeding season was poorly understood until recent studies combining satellite telemetry (Petersen et al. 1995) and aerial survey techniques, documented locations used by Spectacled Eiders during this period (Figure 7). Post-breeding flocks of staging and molting Spectacled Eiders were surveyed in Mechigmenan Bay, on the eastern coast of Russia’s Chukotsk Peninsula (W. Larned, pers. comm.); Alaska’s Ledyard Bay, southwest of Point Lay (W. Lamed, pers. comm.); Peard Bay (Laing and Platte 1994; W. Lamed, pers. comm.); Norton Sound (Lamed and McCaffery 1993; W. Lamed, pers. comm.), and 80 km south of St. Lawrence Island (W. Lamed, pers. comm.). Lamed (pers. comm.) has found eiders isolated in relatively small areas in both Ledyard Bay and Norton Sound. Preliminary information suggests males from the YKD and AR use all major molting/staging areas (M.R. Petersen, pers. comm.). Females from the YKD were found in Norton Sound (Petersen et al. 1995); females from the NS were found in the other major molting/staging areas (M.R. Petersen, pers. comm.). In March and April 1995, the combination of satellite telemetry (Petersen et al. 1995) and aerial survey techniques (W. Lamed, pers. comm.) helped biologists discover Spectacled Eiders in late winter. Information from a single satellite transmitter signal from a female Spectacled Eider directed biologists to an area 110 km NNE of St. Matthew Island in the north central Bering Sea. In March, they found large, dense flocks of Spectacled Eiders in small holes in the nearly-continuous sea ice. Spectacled Eiders were seen in the same vicinity in April, but observers had the impression that open water was more abundant and Spectacled Eiders were more sparsely distributed. Dau and Kistchinski (1977) estimated the world’s breeding population of Spectacled Eiders at about 100,000 pairs in the early 1970s. Because of a lack of data from most of the species’ breeding range, this preliminary estimate was derived by determining local densities at a few sites, and then extrapolating range-wide. In recent years, however, more quantitative estimates have been obtained in all 3 major breeding areas. Population estimates for the YKD, NS and AR have been calculated based on data from aerial surveys. On the YKD, the dramatic population decline over the last 2 decades (Stehn et al. 1993) has resulted in an uncorrected population estimate (i.e., not expanded by a visibility correction factor) of fewer than 3,000 breeding pairs in each of the last 4 years (Stehn et al. 1993; R. Platte, pets. comm.). In 1993, 1994, and 1995, a broad-scale fixed-wing survey yielded uncorrected estimates for the arctic coastal plain of greater than 9000, 7000, and 7000 total birds, respectively (Lamed and Balogh 1994; G. Balogh, pers.comm.). Data from 13
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 24 and 25: Figure 4. Yukon-Kuskokwim Delta loc
Page 26 and 27: DEL?A RUSSIA SPECTACLED EIDER RANGE
Page 28 and 29: helicopter surveys in the Prudhoe B
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
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. feasible if post-fledging staging
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presumed that their activities have
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contaminants within Spectacled Eide
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limited ability to withstand additi
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surface after a year and is no long
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. The reproductive stages (eggs, yo
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is inadequate to sustain “normal
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___________ 1967. The geese of the
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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
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________ P.R. Wade, R.A. Stehn, and
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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
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TASK I — [37 E12 EI.3 fTYU —PRI
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TASK PRIOR- Dj ITYU — — A12.3 2
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— TASK U — 135.2 PRIOR- TASK DE
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TASK U PRIOR- ITY U TASK DESCRIPTIO
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TASK PRIOR. U — DS.3 3 TASK DESCR
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The final risk factor is the effect
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This PVA will treat two population
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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
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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
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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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