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Spectacled Eiders on Yukon Delta NWR
Melissa Gabrielson
Wildlife Biologist
Yukon Delta NWR
February 15, 2011
The Quest for Recovery Continues - Yukon Delta NWR – February 15, 2011
1
A Threatened Species
 Listed
as threatened in 1993
 Breeding pair numbers declined by 96%
The Quest for Recovery - Yukon Delta NWR - February 15, 2011
2
A Threatened Species
 Factors
affecting
Spectacled Eider
population
 Lead poisoning
 Predation
 Human activity
The Quest for Recovery - Yukon Delta NWR - February 15, 2011
3
A Threatened Species
 Conservation
measures
 Lead shot banned
 Hunting and egging prohibited
 Research
efforts
The Quest for Recovery - Yukon Delta NWR - February 15, 2011
4
Meet the Spectacled Eider
 Long-lived
 High
adult survival
 Small clutch size
 Delayed sexual
maturity
 Extensive parental
care
The Quest for Recovery - Yukon Delta NWR - February 15, 2011
5
Meet the Spectacled Eider
 Adapted
to marine and freshwater
environments
 Salt glands
 Adapted
to extreme temperatures
 Decrease daily maintenance costs
 Use energy reserves
The Quest for Recovery - Yukon Delta NWR - February 15, 2011
6
Where Can You Find Eiders?
Figure from Petersen et al. 1999. At-sea distribution of spectacled eiders: A 120 year-old mystery resolved. Auk 116:
1009-1020
The Quest for Recovery - Yukon Delta NWR - February 15, 2011
7
They Winter Where?
Figure from Peterson, M. R. and D. C. Douglas. 2004
and population change. The Condor 106: 79-94
. Winter ecology of spectacled eiders: Environmental characteristics
The Quest for Recovery - Yukon Delta NWR - February 15, 2011
8
They Winter Where?
 Found
in open water
between ice packs
 Benefits
○ Decrease energy costs
○ Reduce effect of storms
 Obstacles
○ Restricted feeding
○ Extreme weather
The Quest for Recovery - Yukon Delta NWR - February 15, 2011
9
Finding a Place to Call Home
 Selecting
nest site
 Small islands
 Peninsulas
 Pond shorelines
 Constructing
nest
The Quest for Recovery - Yukon Delta NWR - February 15, 2011
10
Eggs
 Oval
Shape
 Light olive green color
 Total eggs 1-11
 Lay one egg every 24 hr
 Incubation lasts 24 days
The Quest for Recovery - Yukon Delta NWR - February 15, 2011
11
Ducklings
Fully covered with down
 Capable of walking,
swimming, and feeding
 Move to marine habitat
 Do not return for 2-3
years

The Quest for Recovery - Yukon Delta NWR - February 15, 2011
12
Who Would Want to Eat an Eider?
 Arctic
fox, red fox, gulls, and jaegers
The Quest for Recovery - Yukon Delta NWR - February 15, 2011
13
Where Does the Research Happen?
 Kigigak
Island
Bering Sea
The Quest for Recovery - Yukon Delta NWR - February 15, 2011
14
Past and Present Research
 Monitor
spectacled eider population
 Adult female annual survival
 Nest success
 Duckling survival
 Recruitment
 Search
plots
The Quest for Recovery - Yukon Delta NWR - February 15, 2011
15
I Found One!!
 Initial
visit
 Identify marked females
 Mark nests
 Number and age eggs
 Subsequent
visits
 Identify marked females
 Nest status
 Egg status
The Quest for Recovery - Yukon Delta NWR - February 15, 2011
16
Got Ya!
 Females
trapped
 Mist nests
 Bow-net traps
 Banding
 U.S. Fish & Wildlife metal
band
 Tarsal Band
 Nasal Disc
The Quest for Recovery - Yukon Delta NWR - February 15, 2011
17
What Have We Found??
Tables taken from: Fischer, J. B., R. A. Stehn, and G. Walters. 2010. Nest population size and potential production of geese and spectacled eiders on the
Yukon-Kuskokwim Delta, Alaska, 2009. Unpubl. Rep., U.S. Fish and Wildlife Service, Anchorage, AK.
The Quest for Recovery - Yukon Delta NWR - February 15, 2011
18
Take Home Message
 Population
is increasing
 More to learn
 On the road to recovery???
The Quest for Recovery - Yukon Delta NWR - February 15, 2011
19
Thank–You
The Quest for Recovery - Yukon Delta NWR - February 15, 2011
20
Additional Slides
 The
following slides were not included
in the slide show
 They contain more details on some of
the methods that we use on Kigigak
Island
The Quest for Recovery - Yukon Delta NWR – February 15, 2011
21
Finding Spectacled Eiders
 Search
designated plots
The Quest for Recovery - Yukon Delta NWR - February 15, 2011
22
Aging Eggs
 Floating
Technique
The Quest for Recovery - Yukon Delta NWR – February 15, 2011
23
Aging Eggs
 Candling
Technique
The Quest for Recovery - Yukon Delta NWR – February 15, 2011
24
Trapping Techniques
 Mist
net
The Quest for Recovery - Yukon Delta NWR – February 15, 2011
25
Trapping Techniques
 Bow-trap
The Quest for Recovery - Yukon Delta NWR – February 15, 2011
26