JOHANNESBURG Zoo has announced its intention to breed a baby gorilla using artificial insemination. Despite encouragement the zoo's two adult gorillas, Max and Lisa, have not produced any offspring. The gorillas, both aged 30, do not have a particularly close relationship; add to this Max's low sperm count and the fact that gorilla babies are born only once every three to four years and the chances of adding to the zoo's gorilla population have been slim.
The zoo has tried artificial insemination once before but the attempt was unsuccessful. According to the curator of primates, Philip Cronje, insemination is not an exact science. Gorillas must be inseminated when they are ovulating, and because there are other variables there is no certainty of success.
Hope springs eternal, though, and now the zoo is to try again. As with the previous bid, semen is to be supplied by the Henry Doorly Zoo in Omaha, Nebraska, USA. Once Lisa has been sedated, the injecting of the semen will be overseen by Nada Wskatoff, an expert on artificial insemination from Henry Dooly Zoo, assisted by local gynaecologists.
According to Cronje, although gorillas come from Africa there are only four in African zoos - two in Johannesburg, one in Pretoria and one in Cairo. Another gorilla in Johannesburg would make the city the proud owner of 60% of gorillas in zoos on the continent.
Weighing between nine and 14 kilograms at birth, gorillas grow up to become massive creatures. Males stand about 1.67 metres tall when grown and can weigh anything from 135 to 228 kilograms. They also have long arms, with one male's "wingspan" measured at 2.8 metres. Gorillas identify each other by their facial and body shapes. While human beings have unique fingerprints, for gorillas it is the nose print that is unique.
Gorillas, particularly the mountain variety, are an endangered species, and Cronje admits there has been resistance from foreign zoos to Johannesburg's efforts to acquire more of the primates. However, zoos have a role to play in the fight against the extinction of the primates: "We are looking at zoos breeding gorillas and then introducing them back into the wild," Cronje revealed.
Of the three subspecies of gorillas, there are no mountain gorillas in captivity and only 620 in the wild. Eastern gorillas number about 4 000 and there are approximately 20 in captivity. Western gorillas are a little better off, numbering between 10 000 and 35 000 and there are 550 in captivity around the world. Max and Lisa are Lowland Western Gorillas.
Max became a household name in 1997 when he was shot by a criminal on the run from police. The man entered the gorillas' enclosure in his efforts to escape and was attacked by Max, who interpreted his presence as a threat to Lisa. The man shot Max twice, but not before the 180kg primate had done some damage. The criminal and the gorilla were hospitalised and both survived the encounter.
