American+Black+Bear+Reproduction

A Female Black Bear reaches breeding maturity at the age of three to four years. With enough nutrition source the female can breed every 2 years however in a non-fit habitat the bear may not mature until the age of five or will often skip breeding cycles if she does not feel healthy enough. There mating season is generally during summer starting approximately from mid-June to mid august. Embryonic diapause prevents the embryos to develop until the mother dens to hibernate through winter. Due this behavior gestation can be seven to eight months although actual development takes sixty days. It has been recorded over time if the mother does not have a sufficient amount of fat reserves the embryos will not develop.

The mating process can be divided into three distinct phases: courtship, mating and refractory period. Courtship can be defined by the act of letting a member of the opposite sex know that one is receptive to sexual advances. Mating refers to the actual act of sexual intercourse and the refractory period is the time in between sexual contact, either with the same partner or another. (Boone et al., 2003)

Initial courtship begins with an approach by the male, he then investigates the olfactory signals emitted by the genital region of the female bear. If the female is receptive she will assume the mating position, however, if unreceptive the female will walk away or in a few cases attack the male. There is also frequent urination. The courtship process culminates in the act of mating.(Boone et al., 2003).



There are several important factors that determine the reproductive success of male American black bears, including the ability to locate a mate, sperm quality and body size. We can see the importance of body size in relation to mating in many species. A larger male bear is more likely to gain access to a sexual receptive female if he is bigger and stronger than the competition. (Kovach & Powell, 2003.) Another important factor is the quality and competitiveness of the male bear's sperm, as females have been recorded with litters of mixed paternity.( Schenk & Kovacs, 1995)
 * Male reproductive success:**

Citations
 * Boone, W., Richardson, M. & Greer, J.,** 2003. Breeding behavior of the American black bear //Ursus americanus//. //Theriogenology// **60**, 289–297.

(Garshelis, D.L., Crider, D. & van Manen, F. (2008). [|//Ursus americanus//]. In: [|IUCN] 2008


 * Kovach, A., & Powell, R.,** 2003. Effects of body size on male mating tactics and paternity in black bears, //Ursus americanus//. //Canadian Journal of Zoology//. **81,** 1257–1268.

Macdonald, David (1984). //[|The Encyclopedia of Mammals:]//


 * Schenk, A., and Kovacs, K.M.** 1995. Multiple mating between black bears revealed by DNA fingerprinting. //Animal Behavior.// **50,** 1483–1490.

//Submitted by Hro//

This picture depicts the steps that take place in black bear mating. 1. the male and female find each other. 2. the male sniffs the female and confirms that she is oestrus. 3. the male mounts the female and conducts the pelvic thrusts. 4. the refractory period begins and they seperate, they may repeat this a few times, and the female may roll out of under the male. This was from the article from the website: [|(http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6TCM-47RJVXT-B&_user=925292&_rdoc=1&_fmt=&_orig=search&_sort=d&_docanchor=&view=c&_acct=C000048244&_version=1&_urlVersion=0&_userid=925292&md5=2313d7b3b7af6e90567d6f86539607ce]

Also: Mating usually happens in July, and both male and female may have more than one mate during the summer.