학술논문

Survival and Growth of Northern Bobwhite Chicks in Western Oklahoma.
Document Type
Article
Source
American Midland Naturalist. Apr2005, Vol. 153 Issue 2, p389-395. 7p. 2 Graphs.
Subject
*NORTHERN bobwhite
*CHICKS
*POPULATION biology
*ECOLOGY
Language
ISSN
0003-0031
Abstract
Knowledge of chick ecology is essential for understanding and managing populations of northern bobwhites (Colinus virginianus). We report on chick survival and growth western Oklahoma during 1997-2002. We used Cox proportional hazard models to estimate chick survival rate. Covariates included mass at time of capture, Julian day of capture and year. Chick mass was the only significant covariate in the model. Survival depended on time since capture because survival increased with chick mass, which concomitantly increased with time since hatch. Because of the dependence of survival on chick mass, we modeled chick growth as a function of age using a logistic model (r² = 0.98). Growth-rate was highest at day 35 post-hatch, which was around the mean capture-to-death survival time for chicks (30.0 ± 4.4 d SE). Our results suggest that the 30-35-d period post-hatching is a critical period in chicks' lives. [ABSTRACT FROM AUTHOR]