Copulatory pattern and behavior in a semi-captive population of Eld’s deer

Male copulatory patterns, female multiple copulation and male post-copulatory guarding were studied in Eld’s deer Cervus eldi in Datian National Nature Reserve, China. Mating behavior in 18 females and 11 males from a group of 61 semi-captive Eld’s deer were observed. The majority (55.8%) of copulations occurred between 15:00–19:00 h. The ejaculatory mount was preceded by an average of 5.1 prior mounts. Successful copulation consisted of a single thrust with ejaculation during one intromission, with no lock. This copulatory pattern is classified as pattern No. 15 (no lock, no intravaginal thrusting, single intromission, and multiple ejaculation) and No. 16 (no lock, no intravaginal thrusting, single intromission, and single ejaculation) under Dewsbury’s scheme (1972) and as No. 16 (no lock, no thrusting, single and brief intromission) under Dixson’s classification (1998). Copulation frequency was 1.5 ± 0.9 times for males/ females with the same female/male per day. The duration of the final mount, which included ejaculation, was brief (3.4 ± 1.3 s), and ejaculation usually terminated copulation. Eleven females copulated more than once in this study: three of them copulated with several males (multi-male copulations) and the remainder copulated with a single male (repeated copulations). Our results indicate that some female Eld’s deer may seek multiple copulations to be a strategy to improve the genetic quality of their offspring or to avoid harassment. Post-copulatory guarding of females by males followed all copulations, with dominant males guarding for significantly longer than subordinate males. Dominant males appear to be more effective at post-copulatory guarding than subordinate males. Subordinate males engaged in a quicker pre-copulatory phase to improve their chances of finishing copulation before being forced to accede to dominant males.