Age, Growth, and Reproduction of the Striped Dolphin, Stenella coeruleoalba , Off the South‐East Coast of South Africa

The striped dolphin, Stenella coeruleoalba , is an oceanic species found worldwide in tropical to warm‐temperate waters. Globally, populations are threatened through direct fishing, bycatch, and pollution. Little is known about the life history of this species in South African waters, and an understanding of basic life history parameters is critical for conservation and management. Age and growth were determined for 61 animals stranded along the southeast coast of South Africa between 1972 and 2012 by counting the number of growth layer groups (GLGs) in longitudinal tooth sections. A von Bertalanffy growth curve was fitted to the data, indicating that physical maturity was reached around 231 cm and 21 years in males and 224 cm and 18 years in females. Analyses of the gonads of 48 individuals showed that males reached sexual maturity between 8 and 12 years of age and between 209 and 224 cm total body length, while females reached sexual maturity between 7 and 8 years and between 213 and 216 cm total body length. Maximum age estimates were 21 years for males and 20.2 years for females. Overall, the life history of the species off southeastern South Africa is similar to that reported for populations elsewhere, with minor geographic variations.