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

populations. The presence of“unique” alleles within specific populations is also important, as
• certain populations may harbor a greater proportion ofthe total species genetic diversity than
might otherwise be expected based on total population size alone. Genetic samples should be
taken from more than one area within each geographically defined nesting population and from
peripheral areas including St. Lawrence Island and the Seward Peninsula. Sampling was initiated
in 1993.
112. Assess evidence for ecological and genetic distinctness ofthe YKD NS. and AR
pjjj~n~ Ifpopulation segments are reproductively isolated, they may exhibit heritable
distinguishing characteristics that warrant special management consideration. Hence, it is
important to evaluate evidence for ecological and genetic distinctness between populations. To
the extent possible, this assessment must carefully sort out differences that are likely heritable
from those that are largely influenced by environmental factors. Direct genetic studies (e.g.
electrophoresis, DNA analysis) may be inconclusive, but adaptive, heritable differences may be
indicated indirectly from examination of other characteristics. Phenotypic and life history traits
and habitat characteristics should be evaluated for each population. Once protocols for incidental
data collection are set up, data for this task can be obtained as part ofother tasks (e.g., birds
handled for banding or at museums).
Nuclear DNA studies completed in 1995 suggested the presence ofone panmictic Spectacled
Eider population. However, heritable differences in suspected female-philopatric species such as
Spectacled Eiders would likely be more evident in mitochondrial DNA. Studies will be initiated in
1996.
113. Determine genetic variability within each ofthree nesting populations. Genotype
frequencies and measures ofgenetic variability obtained from nuclear and mitochondrial DNA
markers can be used to assess within-population breeding structure (i.e., potential inbreeding) and
to compare population measures of genetic diversity with known aspects ofeach populations’
ecology (e.g., recruitment and breeding population size). Comparisons should be made between
present population levels ofgenetic diversity- and estimates based on samples obtained from
museum specimens collected from the same areas prior to population declines (see data obtained
for task Hi). The magnitude ofchange in genetic diversity and population gene frequency should
be used to evaluate the potential effects ofdeclines in effective breeding population size and
degree ofisolation from other nesting populations.
I. Diseases. Parasites. and Physiological Condition
Il. Screen eiders for diseases and parasites. Disease and parasite screening should be completed
on all eiders salvaged or collected for other purposes; collecting birds specifically for disease or
parasite screening is not warranted at this time.
12. Investigate physiological condition ofSpectacled Eiders Whether caused by poor food
supplies, chronic oiling, metal contamination, or other factors, poor physiological condition could
result in unsustainable mortality levels. Determining whether body condition in Spectacled Eiders
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