Musth and Communication
Biology 342 Fall 2010
Musth and Reproduction
The reproductive behavior of elephants is relatively unique (Hollister-Smith 2007). Their reproductive strategies are highly influenced by their social structure (Rasmussen. L. E. L 2005). In both African elephants (Loxodonta africana) and Asian elephants (Elephas maximus) females remain with their natal herd, while males are forcibly ejected from their natal herd when they begin to mature, at around 14 years of age (Ganswindt 2010), after which they generally live in bachelor herds (Druce, Schulte 1999). Elephant mating season is less defined than it is in other ungulates (Poole 1987). While the majority of female African elephants are fertile during and after the rainy season, out-of-season breeding is not uncommon (Poole 1987). Females are fertile for a short period of time, only 3-6 days every 3-9 years in African elephants (Hollister-Smith 2007). To overcome this, males must have a highly effective method of seeking out receptive females in order to reproduce.
Male elephants undergo a phenomenon similar to rut (Poole 1987, Eisenberg). This phenomenon, known as ‘musth’ from the Urdu word for ‘intoxication’ (Sukumar 101). Originally thought to exist only in Asian elephants, it has now been identified in African elephants as well (Ganswindt 2005). Males in musth will leave their bachelor herd to seek out females in estrus, and return when they drop out of musth (Druce). Musth males are known to display heightened aggression, attacking both elephants and non-elephants at higher rates (Rasmussen, H. B. 2008). While in musth, males utilize intricate chemical signals to communicate their state to females and other males.
Musth is accompanied by numerous physiological changes in bulls. The key indicators of musth are near-constant urine dribbling, often resulting in algae growth on the penis, swelling of the temporal glands, and characteristic temporal gland secretions, (O’Connell 7). While both male and female African elephants produce temporal gland secretions, the secretions of musth males is markedly different from that of females and nonmusth males (Sukumar 154-155).
Figure 1: Temporal gland secretions