Reproductive Ecology of American Black Bears in the Alleghany Mountains of Virginia, USA

We studied reproduction of American black bears (Ursus americanus) in western Virginia from 1994 to 2003. We handled 326 ≥2‐year‐old female black bears 672 times during summer trapping and followed 176 of these individuals through 424 winter den seasons. We examined 183 litters consisting of 455 cubs. Primiparity occurred at mean and modal ages of 3.8 and 3 years, respectively. Composite mean litter size was 2.49 (SE = 0.06) cubs/litter; 3‐ and 4‐year‐olds had smaller litters than older bears. We tracked reproductive synchrony using 5 indices and documented a resetting of this synchrony, likely in response to hard‐mast failure. The amplitude of oscillations in synchrony indices dampened through time after the synchronizing events. Documentation and quantification of relationships between nutrient availability, reproduction and population dynamics can be used to inform population modeling efforts and more accurately forecast harvest.