Balancing ecological costs and benefits of fire for population viability of disturbance-dependent butterflies

Disturbance is a fundamental ecological process and driver of population dynamics. Ecologists seek to understand the effects of disturbance on ecological systems and to use disturbance to modify habitats degraded by anthropogenic change. Demographic responses by plants to disturbance are often well described, but demographic responses by animals are less understood. This limits development of applied strategies that leverage disturbance to augment animal populations.
We estimated demographic and behavioural responses of an endangered butterfly, Fender's blue, Plebejus icarioides fenderi, to experimental burning in Oregon, USA. We monitored butterfly vital rates for four years post-fire.
Prescribed fire killed Fender's blue larvae. However, fecundity was higher relative to reference/unburned areas for two years after the burn and overwinter larval survivorship was higher for a year after the burn. Fire treatments did not influence adult movement behaviour.
We used matrix models to pro...