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

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. AlS. Produce a handbook summarizing all information on identifying, ageing and sexing Spectacled Eiders This information, including plumage sequences and morphology, is needed to assist with ageing and sexing birds in the hand and during aerial, boat and ground surveys. B. Abundance and Distribution Bi. Delineate and monitor breeding populations Changes in listing status (Threatened to Endangered, Endangered to Threatened, Threatened to delisted) will be based on total numbers ofbreeding birds and changes in the numbers of breeding birds in the three breeding populations (YKD, NS, AR).. Breeding populations cannot be adequately monitored until the. major breeding areas are delineated. Presently only the YKD breeding area is thoroughly described and mapped; the geographic distribution and relative densities of breeding pairs on the NS and AR are currently being determined. Management actions to prevent extinction depend upon knowing whether a population is declining rapidly or has already declined to critically low numbers. Thus, population monitoring is critical for species recovery. Surveys for monitoring eider populations must be efficient and affordable to be maintained over extended periods. Aerial surveys appear to offer the greatest potential for cost-efficient, long-term surveys over the breeding range of the species. If surveys indicated that all three populations were declining, a common causative problem or problems would be indicated. In contrast, different trends among populations would suggest that the primary causes of observed declines occurred on the breeding grounds or on distinct at-sea ranges. Trend and abundance information will assist in setting priorities for tasks to identify obstacles to recovery and causes of decline. Trends and abundance estimates should be of sufficient accuracy and precision to satisfy the Recovery Criteria. Bi. 1. Determine the breeding range and relative abundance of Spectacled Eiders on the Ni Experimental surveys initiated in 1992 defined the geographic limits and relative abundance of this breeding population. (See task B1.4.2.4 for long-term monitoring on NS). Completed. Bl .2. Determine the breeding range and relative abundance ofSpectacled Eiders in AR The distribution and relative abundance of the AR population is poorly defined. Bi .2.1. Complete geographically extensive surveys across AR. The Service has attempted waterfowl breeding pair surveys in AR for a few years; survey results from 1993 and 1994 permitted gross delineation of Spectacled Eider breeding areas and relative numbers in AR. Analysis and mapping of general range were completed in 1995. B1.2.2. Quantify breeding population size on the Indigirka River Delta, AR. An intensive survey for breeding pairs on the Indigirka in 1994 was completed. 54
. B1.3. Determine the breeding range and relative abundance of Spectacled Eiders on St Lawrence Island. Residents of St. Lawrence Island report that Spectacled Eiders are still nesting on the island and they believe nesting numbers may be substantial. The possibility that a viable nesting population is extant on St. Lawrence Island should be investigated, either with aerial or ground-based surveys. BI.4. Monitor trends and generate breeding pair abundance estimates for the three breeding populations. At present, aerial ‘surveys are the only technique known to be feasible for monitoring very wide ranging populations such as on the NS and AR. The effectiveness of current surveys (NS and YKD coastal breeding pair aerial survey) should - be evaluated in light of the Recovery Criteria. If precision requirements in the Recovery Criteria can not be met with current methods then survey design should be re-evaluated and modified. Power analyses to determine the magnitude ofpopulation change detectable on current surveys should guide decisions on survey effort and frequency. Results of Bi. 1. and B1.2. will define the geographic range and relative abundance of NS and AR populations in order to design appropriate surveys for these regions. B1.4. 1. Develop methods for determining visibility correction factors. Visibility correction factors with associated inter-annual variances are necessary to provide population size estimates from surveys. Biologists generally agree that habitats differ significantly between the arctic (NS, AR) and subarctic (YKD), and that waterfowl visibility differs between the regions even when aerial survey methods are the same. Hence, methods for determining visibility correction factors may need to be specific for each region. The relative merits of various methods for developing correction factors should be assessed, including ground and aerial methods at different frequencies (e.g., annual or less frequently). Once developed, these methods will be incorporated into the surveys in task Bl .4.2. Following two years of experimental assessments on the YKD (tasks BL.4.1.l and BL.4.1.4), the relative utility ofaerial and ground surveys for monitoring Spectacled Eider breeding populations should be re-evaluated. B1.4. 1.1. Develop visibility correction factor methods for the YKD aerial survey This task may be possible using existing data from air and ground surveys, although these data sets are not directly comparable. Experimental use of helicopters or expanded fixed-wing surveys may require prior coordination with local communities (following task A4. 1.1). BL.4.1.2. Develop visibility correction factor methods for the NS aerial survey Recent helicopter:fixed-wing survey comparisons completed by industry contract biologists should be evaluated to determine whether they provide valid methods for calculating visibility correction factors on the NS. If not, then alternative methods should be designed and implemented. 55
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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
Page 10 and 11:
LIST OF FIGURES Figure 1. Breeding
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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 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 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
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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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