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

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. The reproductive stages (eggs, young, adults) where fox predation is most serious should be determined, to guide possible control activities (task A13. 1). Inter-annual variation in fox predation and the role ofbuffer species should be evaluated. 02. Evaluate Spectacled Eider population-wide control offoxes as a means to improve reproductive success of Spectacled Eiders. On islands where foxes can be completely eliminated, fox control has been implemented to increase local waterfowl production (also see task A13. 1). Previous experiments with fox control on the YKD, however, indicate that attempts to control fox predation rates by reducing fox numbers with the experimental methods will not be successful on awide scale. Yet, since predator control is one ofthe few tools currently available with any - hope ofaffecting Spectacled Eider survival, further assessment ofthe feasibility and effectiveness ofwidespread fox control for boosting Spectacled Eider survival is warranted. The impacts of fox removal on eider productivity, and adult survival, iffeasible, should be studied at two or more ecologically similar, non-island sites (i.e., control and removal areas). The feasibility ofwidespread control offoxes should then be evaluated. 03. Determine gull foraging patterns and population trends on the YKD. These ongoing studies are designed to assess: (1) gull population size and historical trends in gull numbers on the YKD; (2) correlations between gull densities and eider densities and correl~tions between gull densities and changes in eider densities; and (3) gull food habits and foraging behavior. Summary results from this study will contribute to task C5.4 by assessing the importance ofavian predation within the YKD eider population. Based on this assessment, expanded studies ofregional gull populations and overwinter survival rates may be warranted. The gull food habits study was concluded in 1995. Spectacled Eider ducklings were not consumed by any ofthe Glaucous Gulls sampled in the Hazen Bay area in 1994. 04. Evaluate population-wide control ofgulls as a means to improve reproductive success 01 Spta~1~d..Ejd~r~. Gull populations are thought to have increased in coastal habitats in recent decades due to increased availability of waste food supplies. If gull predation on young eiders is determined to be an obstacle to recovery (tasks G3 and C5.4), the potential means for reducing predation by controlling gulls should be identified, then the feasibility and effectiveness ofguil control should be investigated. A study to assess the impacts ofgull removal on Spectacled Eider productivity should then be implemented. The study should be conducted on at least two ecologically similar, control and removal areas. The feasibility ofwide-spread control of gulls should be considered. Control measures may include eliminating gull colonies through reducing gull food supplies (e.g., improving landfill management and changing fishery waste disposal methods) or repetitive nest destruction (see also tasks Al 1.1, A13.2 and A13.3). H. L~n~ti~a Hl. Determine population structure and gene flow between the major breeding populations The magnitude ofvariation in gene frequency among nesting populations is a function ofthe rate ofinter-populationgene flow and effective breeding population size. Nuclear and mitochondrial DNA gene frequencies can be used to assess the degree ofreproductive isolation among nesting 72
populations. The presence of“unique” alleles within specific populations is also important, as • certain populations may harbor a greater proportion ofthe total species genetic diversity than might otherwise be expected based on total population size alone. Genetic samples should be taken from more than one area within each geographically defined nesting population and from peripheral areas including St. Lawrence Island and the Seward Peninsula. Sampling was initiated in 1993. 112. Assess evidence for ecological and genetic distinctness ofthe YKD NS. and AR pjjj~n~ Ifpopulation segments are reproductively isolated, they may exhibit heritable distinguishing characteristics that warrant special management consideration. Hence, it is important to evaluate evidence for ecological and genetic distinctness between populations. To the extent possible, this assessment must carefully sort out differences that are likely heritable from those that are largely influenced by environmental factors. Direct genetic studies (e.g. electrophoresis, DNA analysis) may be inconclusive, but adaptive, heritable differences may be indicated indirectly from examination of other characteristics. Phenotypic and life history traits and habitat characteristics should be evaluated for each population. Once protocols for incidental data collection are set up, data for this task can be obtained as part ofother tasks (e.g., birds handled for banding or at museums). Nuclear DNA studies completed in 1995 suggested the presence ofone panmictic Spectacled Eider population. However, heritable differences in suspected female-philopatric species such as Spectacled Eiders would likely be more evident in mitochondrial DNA. Studies will be initiated in 1996. 113. Determine genetic variability within each ofthree nesting populations. Genotype frequencies and measures ofgenetic variability obtained from nuclear and mitochondrial DNA markers can be used to assess within-population breeding structure (i.e., potential inbreeding) and to compare population measures of genetic diversity with known aspects ofeach populations’ ecology (e.g., recruitment and breeding population size). Comparisons should be made between present population levels ofgenetic diversity- and estimates based on samples obtained from museum specimens collected from the same areas prior to population declines (see data obtained for task Hi). The magnitude ofchange in genetic diversity and population gene frequency should be used to evaluate the potential effects ofdeclines in effective breeding population size and degree ofisolation from other nesting populations. I. Diseases. Parasites. and Physiological Condition Il. Screen eiders for diseases and parasites. Disease and parasite screening should be completed on all eiders salvaged or collected for other purposes; collecting birds specifically for disease or parasite screening is not warranted at this time. 12. Investigate physiological condition ofSpectacled Eiders Whether caused by poor food supplies, chronic oiling, metal contamination, or other factors, poor physiological condition could result in unsustainable mortality levels. Determining whether body condition in Spectacled Eiders 73
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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
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DEL?A RUSSIA SPECTACLED EIDER RANGE
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helicopter surveys in the Prudhoe B
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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 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
Page 126 and 127: Table 1-2. Results of simulation wh
Page 128 and 129: Hilborn, R. and C.J. Walters. 1992.
Page 130 and 131: 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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