Social monogamy is a common reproductive strategy in birds and is present in Western Burrowing Owls. However, differences between behaviorally observed and genetically determined parent-offspring relationships are noted in many socially monogamous species. Genetic mismatches between nestlings and caregivers arise in at least two ways: extra-pair fertilization (EPF) and conspecific brood parasitism (CBP). CBP is expected to occur in species nesting in high density, where nesting sites are limited, and host nests are available for extended periods of time. Indeed, Burrowing Owls fit these criteria. Previous studies of parentage (e.g., Johnson 1997) in a declining California population of Burrowing Owls report that EPF resulted in 5-10% of offspring and that CBP possibly occurred as well. We aimed to determine parentage patterns in a Burrowing Owl population of southern Idaho and to compare our results with Johnson’s (1997). We isolated DNA from blood and used microsatellite regions to detect genetic mismatches between nestlings and their caregivers. Our poster reports initial results and discusses ecological correlates of EPC and CBP in southern Idaho Burrowing Owls.
Jarod Armenta, ’15
Sponsor: Marty Condon