Reproductive Season of the Scalloped Spiny Lobster Panulirus homarus Along the Coast of Oman: Management Implications

Abstract

The spiny lobster Panulirus homarus is widely distributed in the Indo-West Pacific. Along  the coast of Oman it supports an artisanal fishery using traps and tangle nets. The egg-bearing incidence of females  caught between 1989 and 2006 were analysed relative to month, lobster size and location of capture. The smallest female with external eggs had a carapace length (CL) of 54.6 mm, but only 9–18% of females of 60–69 mm CL carried eggs. This percentage increased significantly above 70 mm CL, and on average, 63% of individuals >90 mm carried eggs. Egg-bearing increased seasonally at the onset of the SW monsoon in May and June, when wind-driven upwelling reduces inshore water temperatures and increases primary productivity. The reproductive season extended over a 9-month period up to  January, with a pause in February to April. No geographical gradient in egg-bearing seasonality was  observed. The prolonged breeding season with multiple broods in large females conforms with the  typical pattern of   tropical palinurids. The 2-month open fishing season (15th October to 15th December) falls within the breeding season, and may be more optimally placed in February to April.