Regional population inferences for the American woodcock

T.J. Dwyer; J.D. Nichols

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USGS · 5210369

Regional population inferences for the American woodcock

T.J. Dwyer·J.D. Nichols

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Abstract

Woodcock (Philohela minor) bandings and recoveries from 1967 to 1977 were analyzed from two large banding reference areas corresponding to existing Eastern and Central harvest units. We examined temporal, age-specific, sex-specific, and geographic variation in both survival and recovery rates, using recently developed stochastic models. Survival rate estimates for females were higher than those for males, and higher for adults than for young. There was no significant difference in recovery rates between young and adults. Recovery rates of Eastern unit birds were higher, and overall survival rates were lower than those of Central unit birds. Survival rate estimates were used with crude production rate estimates in a simple modeling effort, and resulting rates of population increase were 1.2 to 1.3 times higher in the Central reference area.

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T.J. Dwyer, J.D. Nichols. 1982. Regional population inferences for the American woodcock. https://pubs.usgs.gov/publication/5210369

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