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

presumed that their activities have minimal effects on bird populations. Yet data are lacking to
demonstrate that biological studies do not affect Spectacled Eider nesting propensity, clutch
size, nesting success, or bird survival. The effects of ground studies, aerial surveys, and
cumulative research-related activities on Spectacled Eiders should be investigated and
quantified. Quantifying the potential effects will also resolve issues of potential bias in
sampling design, guide mitigation measures to minimize investigator effects and permit an
assessment of whether further, intensive studies are appropriate. This information is also
important for addressing the hypothesis that human disturbance contributed to the Spectacled
Eider decline or is an obstacle to recovery (task CS.7).
C3. 1. Evaluate the effects of nasal markers. On-going marking studies include both nasal
markers and leg bands. Since birds are merely observed and not re-captured for marker
identification, nasal markers provide substantially more reliable re-sighting rates than do
less visible leg bands. Although nasal markers are widely used on waterfowl and are
presumed to have minimal adverse effects, data are lacking to demonstrate that marker
attachment does not affect survival, nesting propensity, clutch size, and nesting success. A
study sbould be conducted on the effects of nasal markers on birds that winter in subarctic,
marine environments, preferably using a similar species rather than Spectacled
Eiders. Quantifying the potential effects will resolve issues ofbias in the sample design
and permit an assessment of whether marking studies are appropriate.
C3.2. Evaluate the impacts of nesting studies. The study should determine an accurate,
unbiased estimate of change in predation or abandonment rates as a result of biologists
visiting nests and gathering information on eggs and hens during incubation. (Three year
study initiated on YKD in 1994).
C3.3. Convene a workshop to develop methods for evaluating other research-related
cff~is. 1. Presently, methods have not been developed that would provide an accurate and
unbiased estimate of the effects of aerial survey over-flights. In addition, the overall
impact of research activities needs to be investigated, including but not limited to camp
establishment and occupation, aircraft support, and, particularly, travel around a study area
not directed to specific nests. Methods for determining specific research effects, such as
increased predation or nest abandonment, need to be determined. Workshop participants
should include biologists with expertise in studying disturbance effects, statisticians, and
Native representatives who are concerned about this issue. Implementation ofadditional
impacts studies should be based on the results of this workshop.
C4. Refine the demographic model for Spectacled Eiders. Understanding the population
dynamics of this species will result in a more realistic assessment of various, potential causes
of decline and obstacles to recovery. An improved model could improve our ability to
determine the costs and benefits of reducing certain obstacles to recovery. The model in
Appendix HI should be refined based on data obtained from tasks under tasks Cl and C2. A
sensitivity analysis should be conducted to assess the effects of uncertainty and environmental
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