Second North American Sea Duck Conference - Patuxent Wildlife ...

More documents

Recommendations

Info

SECOND NORTH AMERICAN SEA DUCK CONFERENCE LARGE-SCALE MOVEMENTS AND HABITAT CHARACTERISTICS OF KING EIDERS THROUGHOUT THE NONBREEDING PERIOD Laura Phillips, Abby N. Powell, and Eric A. Rexstad USGS, AK Cooperative Fish and Wildlife Research Unit; fslmp@uaf.edu Alaskan-breeding king eiders (Somateria spectabilis) molt wing feathers and over winter in remote areas of the Bering Sea, precluding direct observation. To characterize timing of migration and habitat used by king eiders during the nonbreeding period, we collected location data of 60 individuals (27 females and 33 males) over three years (2002-2004) from satellite telemetry and obtained oceanographic information from remotely-sensed data. Mean date of dispersal from breeding areas and arrival at wing molt sites differed by sex and among years. Males and female eiders did not show any evidence of sexual segregation on wing molt sites. Male king eiders dispersed from breeding areas, arrived at wing molt sites, and dispersed from wing molt sites earlier than females in all years. King eider wing molt locations included areas along the Chukotsk, Kamchatka, and Alaska Peninsulas, as well as St. Lawrence Island, Anadyr, Olyutor, Karagin, Bristol and Kuskokwim Bays, the Beaufort Sea, and the coast of Russia near Khatyrka. For males, earlier arrival dates at wing molt sites were correlated with higher latitudes of these sites. Winter locations were found along the Chukotsk, Kamchatka, and Alaska Peninsulas, Olyutor and Bristol Bays, and the Gulf of Alaska. Female king eiders that wintered farther south returned to breeding areas earlier the following summer. Distributions of molt and winter locations did not differ by sex or among years. We suggest that of the variables considered for analysis, distance to shore, water depth, and salinity best describe king eider habitat throughout the nonbreeding period. King eiders were located closer to shore, in shallower water with lower salinity than random locations. During the winter, lower ice concentrations were also associated with king eider locations. This study provides some of the first large-scale descriptions of king eider migration and habitat outside the breeding season. 34 ANNAPOLIS, MARYLAND, USA NOV. 7-11, 2005
SECOND NORTH AMERICAN SEA DUCK CONFERENCE PACIFIC COMMON AND KING EIDER SPRING MIGRATION, SITE FIDELITY AND POPULATION STRUCTURE: INSIGHTS GAINED FROM LONGER-LASTING SATELLITE TRANSMITTERS Lynne Dickson¹, Tim Bowman², Andrea Hoover,¹ and Garnet Raven¹ ¹Canadian Wildlife Service, Room 200, 4999-98 Ave., Edmonton, Alberta, Canada T6B 2X3; lynne.dickson@ec.gc.ca ²USFWS, 1011 East Tudor Road, Anchorage, Alaska, USA, 99503 Satellite transmitters deployed on Pacific common (Somateria mollissima) and king eiders (Somateria spectabilis) on their breeding grounds in central arctic Canada in June 2003 lasted nearly twice as long on average as transmitters we had deployed in the previous six years. Nearly all transmitters from earlier years ceased functioning by the end of winter, whereas 21 of 28 transmitters deployed in 2003 lasted several more months, thus providing new information on timing and routes of spring migration, nesting and molting site fidelity, and population structure. For both species, all females returned to the same nesting area as in the previous year (n=9), whereas males all migrated to different locations to breed (n=11). However, despite breeding in a different area, 7 of 8 males returned to the same postbreeding molting area as in the previous year. In all years, we found that both male and female Pacific common eiders wintered in the same area off the southeastern Chukotsk Peninsula and St Lawrence Island. Therefore, the wide distribution of males during the second nesting season suggests that this wintering area is critical for Pacific common eiders throughout their entire breeding range in arctic Canada and northern Alaska. Spring migration occurred over a two-month period from mid April to mid June. Key staging areas for both species were Ledyard Bay and the polynia in southeastern Beaufort Sea. Daily locations obtained for six Pacific common eiders indicated birds heading for Canada to nest followed the shorefast ice edge rather than the Alaskan coast. They crossed the Alaskan Beaufort Sea in less than a day, although all but one stopped briefly at least once on the way. These data on spring migration have provided a better understanding of vulnerability of eiders to offshore oil and gas development in the Beaufort Sea. NOV. 7-11, 2005 ANNAPOLIS, MARYLAND, USA 35
Page 2: Many Thanks To:
Page 8 and 9: SECOND NORTH AMERICAN SEA DUCK CONF
Page 27 and 28: Daniel Rosenberg and Michael P. Pet
Page 31 and 32: John Reed and Paul L. Flint SECOND
Page 39: SECOND NORTH AMERICAN SEA DUCK CONF
Page 61 and 62: Benoît Bruneau and Magella Guillem
Page 85 and 86: Mark Desholm SECOND NORTH AMERICAN
Page 91 and 92:
Ian Gereg SECOND NORTH AMERICAN SEA
Page 93 and 94:
SECOND NORTH AMERICAN SEA DUCK CONF
Page 95 and 96:
Page 97 and 98:
David Kidwell and Matthew C. Perry
Page 99 and 100:
Page 101 and 102:
Page 103 and 104:
Page 105 and 106:
Katherine Mehl¹ and Mark Gloutney
Page 107 and 108:
Page 109 and 110:
Page 111 and 112:
Page 113 and 114:
Page 115 and 116:
Page 117 and 118:
Gregory J. Robertson SECOND NORTH A
Page 119 and 120:
Nora A. Rojek SECOND NORTH AMERICAN
Page 121 and 122:
Page 123 and 124:
Diana V. Solovieva SECOND NORTH AME
Page 125 and 126:
Page 127 and 128:
Page 129:
Allard, Karel 5, 62 Anderson, Eric
show all

Second North American Sea Duck Conference - Patuxent Wildlife ...

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?