Young Pete seemed too small to be mating with his older Aunt Juliet, and he was lucky not to have been run off by a larger male. Both are daughters of Shadow, the year-old matriarch of the clan in the Eagles Nest Township area. On May 31, Juliet separated from her male yearlings Luke and Skywalker in preparation for mating.
The yearlings, on their own for the first time and weighing 51 and 61 pounds, spent much of the next several days up trees. Yearling Luke came down and approached Juliet making plaintive sounds that showed he wanted contact. She scrambled after him and ran him back up the tree. She shortly moved on with Pete close behind. Researchers realized they had an unusual opportunity to videotape a male-female pair. Both bears had been studied for years and had learned to ignore researchers.
The pair foraged on ant pupae for a few minutes. Pete tried three times to mount Juliet. At PM, he remained mounted until PM. During the final 21 minutes, Pete made fluttering thrusts that researchers believe indicate intromission and ejaculation. Black bear females are thought to be induced ovulators.
Consistent with that, black bears copulate for long periods, and the male has a penis bone called a baculum. Copulation is vigorous and apparently exhausting for the male, which helps explain the 20 percent weight loss mature males undergo during late May and June.
The coastal population of bears in North Carolina includes the world record for largest black bear ever recorded. It was pounds and legally harvested, or hunted, in in Craven County, North Carolina. We were taken aback at first because we realized these young bears were pretty big. Some of the yearling male bears we captured and released weighed in excess of pounds, and some of the yearling female bears weighed more than pounds. A healthy rural bear is typically between 40 to 75 pounds.
That led us to examine whether these young females in particular were able to breed at 1 and a half years of age, and then sustain the pregnancy to give birth to cubs that would recruit into the population. As part of our study, we determined that young female bears in the Asheville area were twice as heavy as the rural bears involved in the study.
At the three forested rural sites one in North Carolina and two in Virginia , the average weights for yearling female bears were about 23 kilograms, or approximately 50 pounds. The urban bears in the study were twice as heavy; they averaged 45 kilograms, or just about pounds. Gould : As we pull all these data together, hopefully we can help the N. Females come into estrus as early as late May and as late as August with the peak of breeding taking place in July.
Females will remain in estrus until they breed or until ovarian follicles begin to degenerate. Dominant males may mate with several females in an area. A dominance hierarchy determines access to females with older, larger males displacing younger males.
Black bears exhibit what is called delayed implantation. During mating, the male and female become almost inseparable, mating repeatedly in the ensuing days. Copulation normally lasts 20 to 30 minutes, but may last up to one hour or more. Estrus females are frequently pursued by more than one male. If another male arrives during the courting ritual, the males may challenge one another for dominance or they may fight if they appear evenly matched. Infanticide among bears is natural but rare.
Boars that encounter sows with cubs will sometimes kill the cubs to initiate estrus and breeding. Sows, especially grizzlies, are very protective of their young and will fight back fiercely. In This Section. What People Are Saying. The soul is the same in all living creatures, although the body of each is different.
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