David Wolfson
John Fieberg
David E. Andersen
William J. Severud
2022
<p><span>Age-structured population models require reliable estimates of cohort-specific survival rates, yet vital rates of younger age classes are often difficult to estimate because of the logistical challenges of monitoring young animals. As part of a study of sandhill cranes </span><i>Antigone canadensis</i><span> in the zone of contact between breeding distributions of the Eastern Population and Midcontinent Population in Minnesota, we monitored first summer survival of 34 sandhill cranes (hereafter colts) by using very-high-frequency and global positioning system–global system for mobile communications transmitters. We estimated daily survival probabilities from 19 to 120 d posthatch by using a generalized linear model accounting for interval censoring, resulting in an estimated period survival rate of 0.52 (90% CI, 0.36–0.71) over summer (100 d). Estimated daily probabilities of survival increased as colts became older and fledged (at 70–75 d posthatch), when they presumably became less vulnerable to predation. Causes of mortality were mostly unknown aside from one case of a collision with a vehicle. There is a scarcity of published colt survival rate estimates for sandhill cranes, and what is available varies widely by study site. Region-specific sandhill crane colt survival rate estimates can inform future management efforts and inform population dynamics research and overall natural history knowledge of sandhill cranes.</span></p>
application/pdf
10.3996/jfwm-21-097
en
Allen Press
Sandhill crane colt survival in Minnesota
article