Asian elephant chemical signals musth

Scott, N.L. and Rasmussen, L.E.L. (2005) Chemical communication of musth in captive Asian elephants, Elephas maximus. In R.T. Mason, M.R LeMaster and D. Miiller-Schwarze (Eds.), Chemical Signals in Vertebrates 10. Springer Press, New York, pp. 118-127. 

To begin the assessment of possible chemical messages between male Asian elephants, responses of captive males to conspecific musth and nonmusth urine were measured. Some obvious disadvantages of captive studies are substantially offret by some real advantages (1) close, accurate behavioral observations in a limited-size enclosure, (2) precise placement of test samples on substrate free of conflicting signals, (3) safe collection of test samples of elephant origin from males whose hormonal status can subsequently be determined. 

Results from the relative time spent investigating each sample demonstrate that the captive male Asian elephants in this study used chemical signals in urine to distinguish between musth and nonmusth urine. The males spent more time investigating the musth urine samples, perhaps to assess the relative dominance of the donor and status as a potential competitor for mates. Olfactory investigation of nonmusth urine shows that there are additional chemical signals other than those related to musth state present in excretions. 

This paper focuses on the ecological and biochemical constraints imposed on such chemical communication. Our analysis of these constraints and their relationship to chemical communication will include (1) the evolution of chemical signals in elephants (2) the operational levels of chemical signals within elephant society (behavioral and/or physiological conditions of the emitters and responders are important constraints) and (3) the types of chemicals available as potential chemical signals. We will focus on two specific chemical signals to illustrate these constraints (1) volatile emissions from male Asian elephants in musth, and (2) (Z)-7-dodecenyl acetate, a female preovulatory pheromone. 

Table II. Temporal properties and chemical identities of potential chemical signals from temporal gland secretions of Asian male elephants in musth...

Rasmussen, L.E.L., Gunawardena, R.A. Rasmussen, R.A. 1997b. Do Asian elephants, especially males in musth, chemically signal via volatiles in breath Chem. Senses, 22, 775. 

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