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

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Criteria for Delisting from Threatened Status A population will be considered for delisting from threatened status when the five factors for listing under the Endangered Species Act are reviewed for evidence of threats to the population and when (1) The population is increasing as judged by the following statistical measures: - the over-protection loss exceeds the under-protection loss, which is calculated using trend data [basedon at least 10 years (1 survey/year) of data but not exceeding a 15 year period] and where loss functions symmetrical around r = 0 with a zero loss for both functions when r 0 (see Appendix II, Figure 11-1); AND - the minimum estimated population size is =6,000breeding pairs; (2) the minimum estimated population size is =10,000breeding pairs over =3surveys (1 survey/year, with surveys preferably being consecutive) or the minimum estimate of abundance exceeds 25,000 breeding pairs in any survey. OR Note that the criteria for delisting a population from threatened status are independent, in that either criterion may be met for delisting to occur. Once recovery has begun, the evidence should be strong that a population is either large, or increasing, self-sustaining, and no longer in foreseeable danger of extinction. Toward achieving the recovery objectives outlined above, this plan establishes intermediate objectives to: (1) identify and, ifpossible, eliminate the cause(s) of the decline; and (2) identify and, ifpossible, eliminate any obstacle(s) to recovery (see Narrative Outline). Achieving these intermediate objectives will almost certainly be required to halt the current population decline(s) and to allow recovery. Substantially increasing our understanding of causes and obstacles as they relate to recovery is not, in and of itself, the primary objective of this recovery plan. For example, the species may recover without the Service ever determining the actual cause for the original decline. Under such circumstances, delisting should proceed if the population has increased to desired levels and appears to be in no danger ofextinction. Estimated date for completion of recovery The estimated date for recovery of the world population of Spectacled Eiders is unknown, for several reasons. First, the cause(s) ofthe decline are unknown. Second, some obstacle(s) to 38
ecovery are unknown or poorly understood. Third, even if all cause(s) and obstacle(s) are identified, it is possible that they are caused by factors that cannot be eliminated or altered sufficiently to allow recovery. As more information becomes available, the recovery date will be estimated in subsequent revisions ofthis plan. B. Strategies for Recovery In “Policy Guidelines for Planning and Coordinating Recovery of Endangered and Threatened Species” (TJSFWS 1990), recovery teams are directed to enumerate actions that address threats to the species ofconcern. In the Narrative Outline, all tasks necessary to achieve full recovery of the species are to be specified. Such an approach is premature for Spectacled Eiders, however. Causes of the dramatic decline of this species, as well as current obstacles to recovery, have yet to be determined. Basic information about the distribution and abundance of Spectacled Eiders throughout the year is fragmentary, as is our understanding of the demography and population dynamics of this species. Whether the nesting populations of Spectacled Eiders in the three primary geographic areas are genetically or demographically distinct is unknown, yet specific recovery actions and priorities may hinge on such a determination. In light of these significant data gaps, an exhaustive list of tasks required to achieve recovery cannot yet be presented. Instead, interim recovery efforts are recommended that proceed simultaneously along three fronts: (1) preliminary management actions targeting known sources of mortality; (2) exploratory data collection and analysis; and (3) hypothesistestlng. The first aspect of this plan’s approach to Spectacled Eider recovery includes management actions: those tasks that typically are identified in the Narrative Outline of a recovery plan to effect a species’ recovery. Management actions to eliminate the threats to a species (be they causes of the decline or obstacles to recovery) can proceed most constructively when those threats have been identified and their effects quantified. Management actions, however, should not be set aside until exploratory data collection has been completed. When possible, managers should strive to eliminate sources of mortality, even if such sources are unlikely to be responsible for the initial decline of the species. Early, effective efforts to reduce mortality and increase productivity will provide additional time for the eiders until researchers have confirmed or identified the actual causes of decline and the most serious threats to the birds’ future. The second aspect of recovery activity--exploratory data collection and analysis--should be a continuation and refinement of the research and survey efforts that were initiated in 1991 after the petition to list this species. To address the many topics in need of elucidation, these efforts will have to be expanded significantly in the immediate future. Truly exploratory data collection probably will continue for at least four more years. 39
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 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 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
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
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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
Page 128 and 129:
Hilborn, R. and C.J. Walters. 1992.
Page 130 and 131:
APPENDIX II TECHNICAL DETAILS OF TH
Page 132 and 133:
The likelihood function for the par
Page 134 and 135:
initial sample. Then the O~ were re
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LU ~0.8 z -J ~0.6 I-ET1 w107 480 m1
Page 138 and 139:
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
Page 152 and 153:
LITERATURE CITED APPENDIX In Bailli
Page 154 and 155:
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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