Habitat Characteristics and Nesting Success of the Western Burrowing Owl in a Suburban Landscape

Articles | By Kerrie Anne T. Loyd and Rhiannon T. Watkins | Accepted February 01, 2019
Abstract:

Burrowing Owls (Athene cunicularia) are a species of conservation concern in most western states. In Lake Havasu City, Arizona, owls are common in desert washes in developed suburban and urban locations. These vegetated and steeply sloping washes host dozens of breeding pairs of owls. Suburban wash habitats may offer benefits such as a larger and more diverse prey base (due to additional and varied vegetation), perch sites, and existing burrows. However, suburban owl populations are susceptible to secondary poisoning, predation, and disturbance from construction. This project examined habitat preferences and reproductive success of Burrowing Owls in Lake Havasu City. We monitored 112 active nests within the Lake Havasu City limits over a 5-year period. We surveyed microhabitat characteristics, including vegetation diversity and cover, wash slope and elevation, burrow characteristics, and presence/absence of predators. Nest success averaged 70% from 2014-2018 and the average number of juveniles produced was 4.1. To date, we have not identified any significant predictors of urban/suburban owl nest success or productivity. A primary cause of owl mortality during this study period was secondary poisoning through exposure to second-generation anticoagulant rodenticides. This research provides baseline data on our local population and will help biologists and managers understand the owls’ urban/suburban habitat preferences.