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

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. feasible if post-fledging staging areas have been identified (task B2.2.3) and may also provide new information about post-fledging areas ifjuveniles are detected coincidentally with other surveys. Presumed high mortality rates for juveniles make this approach less favorable. The best methods should be determined through preliminary studies. These studies should evaluate juvenile mortality beginning after day 45, when the ducklings are fully feathered with full wings, but before they migrate to the coast. Follow-up surveys of post-fledging habitats should be incorporated in project plans (see task B2.2). C2.3.1. Implement juvenile post-fledging mortality study on the YKD C2.3.2. Implement juvenile post-fledging mortality study on the NS C2.3.3. Implement juvenile post-fledging mortality study in AR C2.4. Quantify duckling mortality. High nesting success may not correlate with high fledging success if ducklings suffer high mortality rates. Further, since predation and lead poisoning are suspected obstacles to recovery, data are needed on duckling survival and fledging rates. Sampling design should account for local and annual variation in duckling survival, which may be substantial. Hence, studies should be conducted at more than one site per breeding population; optimally at the same sites as those used to determine egg production, recruitment, and adult mortality. C2.4. 1. Assess and modify methods for radio-tracking hens on the YKD to monitor bro&.znQlIality.. Studies on duckling mortality should be continued at Hock Slough until sufficient data are available to evaluate variability in duckling survival. Study protocols, which presently are unable to adequately monitor mortality during the first two weeks post-hatch, should be assessed and modified if feasible. Mortality immediately post-hatch and while broods are moving from nesting to initial broodrearing habitats--a presumed period of high mortality--might be detected with more intensive monitoring. Project was initiated in 1993. C2.4.2. Implement radio-tracking of hens on the MS to monitor brood mortality Comparable data on brood mortality are needed from both developed and undevelopedsites on the MS to address the hypothesis that industrial development has adversely affected local populations. Further, this information is needed to interpret comparisons between NS and other populations. Current studies within the MS oil fields could be duplicated in ecologically similar, undeveloped sites. • C2.4.3. Implement radio-tracking of hens in AR to monitor brood mortality C2.5. Monitor brood production. Brood surveys would provide the most direct evidence ofannual breeding success prior to fledging. Production data collected thus far primarily have been very local in nature (associated with research projects) and may not be 62
. representative of the breeding populations as a whole. Surveys should be designed to be representative of the breeding populations. C2.5. 1. Monitor brood production on the YKD C2.5.2. Monitor brood production on the NS C2.5.3. Monitor brood production in AR~ C2.6. Quantify clutch sizes and nest and egg survival rates. Based on current data and preliminary modeling (Appendix III), low production is not suspected to have caused the observed population declines. Yet for detailed demographic modeling to be accurate, annual production data should be gathered in conjunction with duckling and adult survivorship data. At least two study sites should- be sampled for each of the three populations. Sampling should include clutch size and hatching success. Studies within each population should be conducted concurrently so that data are statistically comparable. Identifying the proximate causes ofegg mortality (e.g., infertility, dead embryos, predation) may illuminate potential obstacles to population recovery. Changes in clutch size and hatching success should be compared among years as well as locations. Some previous studies may provide data for comparison with on-going studies and these data sets should be evaluated. C2.6. 1. Monitor nesting success on the YKD. Reproductive success data have been gathered at the Hock Slough and Kigigak Island study sites since 1992, providing preliminary input for modeling. Although a low priority by itself, annual reproductive success data should continue to be gathered at these sites coincidentally with the ongoing survivorship studies (task C2. 1.1), if feasible, so that site-specific population dynamics can be assessed. Further, indications of high frequency of egg addling rates on the YKD need to be investigated to determine if addling has increased and what effect it may have on total production. C2.6.2. Monitor nesting success on the NS. Comparable data on nesting from both developed and undeveloped sites on the NS may be useful for addressing the hypothesis that industrial development has adversely affected local populations. Further, this information is needed to interpret comparisons between NS and other populations. Current studies within the NS oil fields could be duplicated in ecologically similar, undeveloped sites. Reproductive success data could be obtained coincident with survivorship studies (task C2. 1.2) or section 7-related evaluations. C2.6.3. Monitor nesting success in AR C3. Evaluate the impact ofbiological studies on eider hatching success and brood survival Based on studies of other species on the YKD and incidental observations, researchers have 63
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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
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 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 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
Page 120 and 121: 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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