IMPACT OF WILDFIRES ON BARN OWL (TYTO ALBA) HABITAT SELECTION IN A VINEYARD AGROECOSYSTEM IN NAPA VALLEY.
Allison Huysman; Humboldt State University; 1 Harpst St., Arcata, CA, 95521; (516) 587-3602; aeh86@humboldt.edu; Matt Johnson
In the world-renowned wine growing region of Napa Valley, California, wine producers install nest boxes to attract barn owls (Tyto alba) which may reduce rodent crop damage. Annual monitoring of 297 nest boxes began in 2015, and devastating wildfires burned over 60,000 hectares in the region in 2017. The fires burned homes and businesses, as well as some vineyards and uncultivated habitat. Little is known about how barn owls respond to drastic landscape changes such as wildfires and this study addresses that gap. Occupancy surveys and GPS tagging before and after these wildfires reveal changes in habitat selection at the nest and hunting scales in a Before-After-Control-Impact study design. Owls were found breeding in recently burned areas that were previously unoccupied, suggesting that wildfires may change the landscape in a way that encourages nest box occupancy. Data from GPS transmitters provide further insight into the effects of the fires on hunting habitat selection. These results have implications for the potential of barn owls to provide rodent pest control as vineyard owners increasingly install nest boxes and as wildfires increase in the western United States.
Wildfire and Wildlife   Student Paper