Hunting habitat use and selection patterns of barn owl (Tyto alba) in the urban-agricultural setting of a prominent wine grape growing region of California
Large scale conversion of uncultivated land to agriculture threatens wildlife and can diminish ecosystem services provided by nature. Understanding how wildlife provision ecosystem services may incentivize wildlife conservation in agricultural landscapes. Attracting barn owls (Tyto alba) to nest on farms for pest management has been documented worldwide, but has not been thoroughly evaluated in vineyard agroecosystems. Napa Valley, California is a renowned winegrape growing region, and viticulturists encourage barn owl occupancy to help minimize plant damage from pocket gophers (Thomomys bottae) and voles (Microtus spp.). This study aimed to establish a basis for revealing the abilities of a predator to provide an ecosystem service to farmers by modelling space and time use of selected habitats. I constructed intensity of use and home range-movement maps using a Time Local Convex Hull (T-LoCoH) analysis from location data obtained from nesting owls. I found that barn owls selected uncultivated habitats when hunting, some of which were relatively rare on the landscape. Though owls did not use them in proportion to their availability, approximately one third of barn owl hunting locations occurred in vineyards. A final analysis showed that the owls’ use of vineyards increased with decreasing amount of preferred uncultivated habitat in the landscape. However, as reported by a previous study, occupancy of nest boxes in vineyards increases with uncultivated habitats nearby. Future research should model landscape composition to determine the amount of preferred habitat necessary to support occupancy as well as hunting in vineyards
