| Popis: |
We studied migration of a female and male Red-tailed Hawk (Buteo jamaicensis) from southern California with satellite telemetry over 9.3 and 6.7 yr, respectively. Previous research suggested the migratory fraction of southern California's Red-tailed Hawk population was limited to juveniles and young adults, and that these hawks ceased migrating once they acquired a territory and mate, usually at 3 yr of age. Both hawks in this study ceased migrating at 3 yr of age, the year they both first nested, and did not migrate for the next 4 and 3 yr, respectively. However, both hawks resumed migrating in 2014, the year with the lowest recorded precipitation in California history. The male did not migrate in 2015, the last year we were able to track his movements, while the female switched between migrating (2015 and 2017) and residency (2016) over the next 3 yr. To our knowledge, our study is the first to document individual raptors displaying such switching behavior. |
