Some Aspects of Reproduction and Age Structures in the Black Bear in North Carolina

Ages were assigned to 151 Nort h Carolina black bears (Ursus americanus) by canine cementum annuli count. Canine teeth collected during the 1969, 1970 and 1971 hunting seasons revealed average ages of 5.17,4.73 and 4.82 years, respectively. The average age increased in the coastal area but decreased in the mountain region. Ages ranged from 0.75 to 22.75 years. Yearlings, 1.75, represented 29 percent of the kill with a high incidence of males. Forty-eight female reproductive tracts indicated corpora lutea counts of 1.00, 2.71 and 2.81 per pregnant female over the 1969 to 1971 period. Active corpora lutea were found in 80 percent of the 3.75 year old females. Female breeding age ranged from 2.5 to 17.5 years. The sex ratio was established at 106 males: 100 females. Embryonic development was noted in only one instance. Egg migration between the horns of the uterus was noted in one instance.

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