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Annual Survival Of Southern Breeding Female Hooded
Mergansers
DUGGER, KATIE M. Gaylord Memorial
Laboratory, School of Natural Resources, Univ. of Missouri, Columbia,
65211
DUGGER, BRUCE D. Gaylord Memorial Laboratory, School of Natural Resources,
Univ. of Missouri, Columbia, 65211
FREDRICKSON, LEIGH H. Gaylord Memorial Laboratory, School of Natural
Resources, Puxico, MO 63960
Because of their relative unimportance to recreational hunters, almost
nothing is known about the population dynamics of waterfowl in the tribe
Mergini in North America. Species-specific annual survival estimates are
important to ecologists and managers both for understanding the evolution
of life histories and for implementation of management plans. Using
capture-recapture methodology, we estimated annual survival of female
Hooded Mergansers breeding in man-made nest boxes in southeast Missouri
from 1987 - 1995. Survival averaged 0.74 + 0.045 (95% confidence limits -
0.652 - 0.828), and analysis suggested lower annual survival in two years.
Annual survival was not correlated with composite winter temperature or
total rainfall variables for the Mississippi Alluvial Valley. Mean
survival was higher than for female Wood Ducks using the same population
of boxes during the same years. Results are consistent with the
characterization of sea ducks as long-lived relative to dabbling ducks.
Annual differences in survival suggested here emphasize the need for
research identifying both the timing and sources of Hooded Merganser
mortality.
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