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

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. Bl.4. 1.3. Develop visibility correction factor methods for the AR aerial survey Since aircraft used in Russian aerial surveys typically differ from those used in Alaska, eider visibility is likely to differ as well. Hence, visibility correction factors are needed specific to this region and the aircraft or observation platform used. Bl.4. 1.4. Develop nest detection correction factor methods for the YKD ground ~ With an unbiased correction-factor for nest detection rates the ground plot data may provide the best annual estimate ofabsolute breeding pair abundance. Present survey design assumes that some nests are missed during these mid’incubation surveys, but the proportion missed is relatively constant between years. Further, it is assumed that Spectacled Eiders nest synchronously and never or rarely re-nest if nests are destroyed after incubation is initiated. Yet these assumptions may not be valid and need to be tested. Detection rates may vary due to differences in habitat, observer training or survey timing; hence, detection or visibility correction factors are needed to provide more accurate abundance and trend estimates. Bl .4.2. Monitor trends in the three populations. Either existing or newly developed surveys should be implemented as soon as acceptable methods incorporating visibility correction factor methods are developed (task Bi .4.1). To meet the recovery criteria, both absolute abundance and population trend data must be monitored in each population. B1.4.2.1. Analyze existing YKD aerial and ground survey data to refine survey m~ibQds.~. Both aerial and ground survey population estimates may be improved by re-stratifying the sample design or re-allocating ground survey effort. Data sets are presently being analyzed to determine whether precision can be improved with changes in the survey design. If re-allocation of effort is warranted, survey methods should be revised accordingly. Additional analyses should: 1) evaluate the effects ofbreeding phenology on results obtained from eider breeding pairs surveys as they are currently conducted on the Yukon Delta, and 2) examine bias associated with extrapolating eider estimates outside of sampled areas as is currently done for~ the Yukon Delta surveys. Potentially, a separate survey for Spectacled Eiders may be i~eeded since the existing surveys were designed primarily for geese and optimization for Spectacled Eiders may be incompatible with objectives for other species. This effort is ongoing. Bl .4.2.2. Continue the YKD coastal breeding pair survey or implement alternative Spectacled Eider survey as determined in Bl .4.2.1. The current aerial survey method incorporates fixed-wing, systematic strip plots over extensive geographic areas. Single birds, breeding pairs, and flocks are enumerated separately to generate estimates of total breeding birds. If task BL.4.1.1 results in 56
. recommendations for expanded surveys, particularly using helicopters, then local villages and the Waterfowl Conservation Committee of the Association of Village Council Presidents should be informed and consulted (see task A4. 1.1). B1.4.2.3. Continue YKD ground plot survey. The ground plot survey provides the only estimate of actual nest numbers. Trends in nest abundance provide critical information about population dynamics. If non-breeding birds return to nesting grounds and are counted on aerial surveys, those surveys may not detect population changes while actual nest numbers or total productivity are declining. In addition, ground plot surveys may assist in evaluating visibility bias on aerial surveys. BL.4.2.4. Design and implement a NS survey. Results of exploratory surveys (tasks B1.1 and B1.4.1.2) should be used to design a survey program for the NS; either continuing or revising the current survey protocol. B1.4.2.5. Design and implement an AR survey. The option of dividing the AR range into two or more survey areas to be surveyed in successive years, with an index area to be surveyed annually, should be investigated. The logistical and economic feasibility of alternate approaches, either an American-led cooperative survey or training Russian pilots and biologists to assume. survey responsibilities for• AR population, should be investigated. The results ofjoint venture surveys with U.S. and Russian biologists, and both Service and Russian aircraft (tasks Bl.2. 1 and B1.4. 1.3), should be helpful in determining the feasibility and quantitative comparability of a Russian-led survey. B2. Delineate at-sea range and relative abundance of Spectacled Eiders by breeding p~pulali~n,. Spectacled Eider distribution away from the breeding grounds is poorly known. Since eiders spend most of their lives at sea, understanding at-sea distribution will be critical to determining and addressing threats to the populations. Identifying the location(s) and timing where annual mortality is greatest would be especially useful for directing research and recovery actions. Other factors that may be influencing population trends, such as marine food abundance and contamination, can only be investigated if at-sea feeding areas are known. Further, it is important to determine whether, where, and when the three breeding populations~ share habitats away from nesting grounds. Such information may reveal differences between the poPulations and their trends. Hence, Spectacled Eider movements and habitats during nonbreeding should be determined for each ofthe three populations. B2. 1. Delineate non-breeding distributions of Spectacled Biders with satellite telemetry Preferably, satellite telemetry would be implemented simultaneously in the three populations to clarify intra-annual range overlap. Due to logistical and cost constraints, however, the three populations were proposed in sequence. In 1995, however, transmitters were implanted in birds from all three populations. 57
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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 ~
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 64 and 65: . AlS. Produce a handbook summarizi
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
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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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