Maladaptive Habitat Use of a North American Woodpecker in Population Decline



Barbara Frei, Department of Natural Resource Sciences, McGill University, Macdonald Campus, Ste.-Anne-de-Bellevue, Quebec H9X 3V9, Canada.



Rapid anthropogenic habitat changes can lead to non-ideal habitat use by animals, often resulting in lower fitness and population declines. An extreme case of use and fitness mismatch is an ecological trap where habitat quality cues are disjointed from the true quality of the habitat. Species primarily associated with anthropogenically altered habitat, such as red-headed woodpeckers (Melanerpes erythrocephalus), may be especially vulnerable to use and fitness mismatch as they encounter novel environmental challenges. We investigated multi-scale habitat use and nesting success of red-headed woodpeckers to assess their vulnerability to mismatches between use and fitness as a result of non-ideal habitat use across multiple scales. We found that habitat characteristics that promote feeding potential such as canopy openness and greater dead limb length appeared paramount and were consistent in use across several spatial scales although reproductive fitness suffered. This contrasts with the assumption that habitat use by nesting birds should instead favor predation avoidance at smaller scales to improve reproductive fitness and suggests that maladaptive, food-based habitat use by red-headed woodpeckers in southern Ontario may result in ecological traps for the species. Whether due to poor habitat choices or costly ones in favor of feeding potential, it is vital to consider this behavior in conservation and management plans for this and similar species. We suggest multi-scale habitat use studies that consider fitness outcomes are critical for species-at-risk in human-modified landscapes.