jp
a buffalo produces buffalo and a bison produces a bison.

Skechers
Female bison are ready to mate when they are two to three years old. Males aren't ready to mate until they are about six. Mating season begins in July and can run through September. When mating season begins, male bison move into female groups and select a female. They then "tend" the female. Males tend a female by staying between her and the rest of the herd. Tending can last for a few minutes or for several days. If a female isn't interested in a male, she will walk away. Males will threaten and sometimes attack other males that try to get too close to a female he is tending. Fights between males can involve headbutting, shoving, or locking horns. The female gives birth to one calf after about nine months. She will go to an isolated area to give birth. Newborn bison are reddish brown and can stand shortly after birth. The mother and her calf will stay isolated from the herd for a couple of days. At about two months, the calf will begin to develop shoulder humps and horns. The calf is usually weaned by the time it is seven months old. Female Buffalos have their first calves at age 4 or 5. They usually calve only once every two years. Although young may be born throughout the year, most births occur in the rainy season when abundant grass improves the nutritional level for the females when they are pregnant or nursing. The female and her offspring have an unusually intense and prolonged relationship. Calves are suckled for as long as a year and during this time are completely dependent on their mothers. Female offspring usually stay in the natal herd, but males leave when they are about 4 years old.

The Cheshire
No they are not the same animal. It is just that some people in the states happen to call bison a buffalo by mistake. There are no wild buffalo living in the US. As far as genetics go, there are different species but the closest they get is their Family which is Bovidae. With reproduction here are the most common two species. Bison (Bison bison) -females mature around 2-3 years old, males mature around 6 or when they are large enough to compete with other males -breeding season: june-sept -gestation: about 280-290 days -calves born: one -females care for young for about one year, dad has no part in the process African Buffalo (Syncerus caffer) -females mature around 5 years old, males mature around 8-9 years old -breeding season: all year but usually at the end of the first rain (june) -gestation: about 340 days -calves born: one -females care for male calf for about two years, females remain with mom until their first calf and even then sometimes stays The water buffalo (Bubalus bubalis) is also different but most people when talking about buffalo are talking about the African ones. Usually you can see them roaming with wildabeast and zebra.