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

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contaminants within Spectacled Eider marine and breeding ranges needs to be compiled and evaluated to identify which contaminants may be adversely affecting Spectacled Eider populations (see task Dl). The summary should: (1) deseribe contaminant concentrations recorded in eiders, other marine birds and marine mammals; (2) interpret inter-population variability in contaminant levels; and (3) compare contaminant levels to concentrations found in other species and to levels known to cause physiological or behavioral effects in waterfowl and marine birds (toxic and chronic effects) (initiated 1994). CS.2. Prepare summary report about competition for food and loss of food supplies due to benthic disturbance. The potential relationships between competition and the observed historical declines and recovery should be evaluated and summarized in a report. Population trends, long-term distribution, and food habits of potential competitors including other marine birds, walrus, and Gray Whales should be examined and compared with these traits for Spectacled Eiders (see task El). The spatial and temporal overlap of Spectacled Eiders with potential competitors should be compiled in a GIS data base. All available data on benthic fauna for at-sea Spectacled Eider habitat should be compiled. In addition to direct competition, food supplies may be inadequate due to benthic damage caused by Gray Whales displacing benthic substrates while they feed. Thus indirect competition through benthic disturbance should be included as part of this hypothesis testing. The levels of resource use overlap, niche breadths, competitor abundance, and benthic disturbance should be evaluated (this task may overlap with tasks CS.5 and C5.9). CS.3. Prepare summary report about harvest. The potential relationships between harvest and the observed historical declines and recovery should be evaluated and summarized in a report. Historical subsistence harvest survey data, where available, and anecdotal data should be collected and examined for comparatibility and potentially for use in examining historical changes in magnitude and distribution of harvest. Historical sport harvest data should be derived from ADF&G and Service harvest surveys and anecdotal data. Factors that may have contributed to historical changes in the subsistence and sport harvests should be identified. C5.4. Prepare summary report about predation. The potential relationships between predation on eggs, ducklings, and adults and the observed historical declines and recOveryshould be evaluated and summarized. The evaluation should consider: (1) gull population trends, and foraging behavior and diets (task G3); (2) correlations between gull and eider densities and changes in those densities on the YKD; (3) changes in fox populations on both the YKD and the NS, and effects of fox control on waterfowl predation (task Gi); and (4) population-level trends for other fox and gull prey species compared with Spectacled Eider population trends. CS.5. Prepare summary report about Bering Sea Fisheries. The potential relationships between fisheries activities and the observed historical declines and recovery should be evaluated and summarized. Ifpreliminary assessment points to potential interaction 66
etween Spectacled Eiders and fishery activities, the spatio-ternporal patterns of Bering Sea fishery activities, both seasonally and across years, should be summarized in a GIS data base. Any available fishery data should be assessed to determine whether these fisheries: (1) impact eider foraging ecology through competition; (2) result in substantial mortality from colliding with lighted boats during periods of darkness or drowning in nets (task A11.4.); (3) disturb benthic substrates where eiders feed; and (4) coincide with the time frame of the eiders’ decline (this task may overlap with tasks CS.2 and CS.9). C5.6. Prepare summary report about industrial development on the NS. The potential relationships between industrial development and the possible declines and recovery should be evaluated and summarized. This summary should incorporate data on the impacts on nesting success, brood success, duckling survival, hen survival, and nesting distribution. The potential effects of any planned expansions or changes of facilities, roads, and other structures or changes in activity levels on recovery should also be evaluated (this task may overlap with task C5.7). CS.7. Prepare summary report about human disturbance. The potential relationships between human disturbance and the observed historical declines and recovery should be evaluated and summarized. Variables such as increases in the local human population, changes in human presence on the breeding grounds (including local residents and biologists), and changes in amount of vehicular disturbance (snow machines, outboard boats, off-road vehicles, aircraft) on the breeding grounds should be considered. C5.8. Prepare summary report about changes in long-term weather patterns and current ±b~izpan~rns.The potential relationships between weather changes and the observed historical declines and recovery should be evaluated and summarized. Long-term changes as well as brief, potentially catastrophic events should be considered. Changes in local (breeding ground) and large scale (Bering Sea) weather conditions should be compared to declines in Spectacled Eiders. Critical periods in the eiders’ annual cycle such as hatch, fledging, transition of young to marine environment, and winter conditions should be examined to identify plausible links between potential or identified weather changes and the eider decline. Information on weather-related changes in primary production, carbon flux to the benthos, standing stocks of benthic biomass, and abundance or species composition~ of eider prey stock may be beneficial. CS.9 Prepare summary report about chronic oiling from bilge pumping in Spectacled Eider wintering habitat. The potential relationships between bilge discharges and the observed historical declines and recovery should be evaluated and summarized. Vessels traveling in the Bering and Chukchi seas may be incidentally contaminating the marine environment by pumping bilge water containing petroleum products. In cold waters, oil degrades very slowly and may pose a persistent hazard to marine animals. Exposure to even small quantities of oil may be harmful or fatal to sea ducks including eiders, especially during severe winter weather. Sea ducks that winter in cold waters likely have 67
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SPECTACLED EIDER RECOVERY PLAN Team
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LITERATURE CITATION U.S. Fish and W
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EXECUTIVE SUMMARY OF THE RECOVERY P
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TABLE OF CONTENTS DISCLAIMER PAGE 1
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LIST OF FIGURES Figure 1. Breeding
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A. Status of the Spectacled Eider R
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) a) j~ 25000 0 2 220000 C ~15000 ~
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B. Causes for Decline and Obstacles
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Increasing interest in avicultural
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Other conservation measures include
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D. Natural History of the Spectacle
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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
Page 72 and 73: . feasible if post-fledging staging
Page 74 and 75: presumed that their activities have
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
Page 86 and 87: ___________ 1967. The geese of the
Page 88 and 89: Dementev, G.P., and N.A. Gladkov (e
Page 90 and 91: ___________ 1 964a. Observations on
Page 92 and 93: 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
Page 98 and 99: KEY Task Duration and Costs TBD - T
Page 100 and 101: 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
Page 106 and 107: — 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
Page 118 and 119: 0.2 0.15 -j i 4 0.1 0 -I 0.05 0.08
Page 120 and 121: emaining before the population reac
Page 122 and 123: ) critical population size; and (2)
Page 124 and 125: 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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