Reproductive seasonality of the nyala Tragelaphus angasi; The interaction of light, vegetation phenology, feeding style and reproductive physiology

Abstract

AbstractIn Ndumu Game Reserve, South Africa, it was found that nyala males exhibited no seasonal sexual cycle. Although conceptions occurred throughout the year, there was a bimodal pattern of conceptions with the peaks in autumn and spring.After referring to other African bovids which also have bimodal patterns of reproductive activity, it was concluded that the cues for the two peaks are as yet unknown but must be provided by light or photoperiod. The factors which ultimately decide the amplitude of the peaks are vegetation phenology and feeding style of the animal. In nyala, peaks are masked by the occurrence of post‐partum oestrous cycles and a gestation period of approximately 7 months.