Gonad development and spawning of the Vulnerable commercial sea cucumber, Stichopus herrmanni, in the southern Great Barrier Reef

摘要: Despite the important ecological roles of commercial beche-de-mer holothuroids in coral reef ecosystems their reproductive biology is poorly studied, including on Great Barrier Reef (GBR). We investigated reproduction Stichopus herrmanni , a commercially species listed as Vulnerable, at One Tree Island, southern GBR. Gonad index, histology and spawning observations indicated an annual cycle with gamete release Austral spring summer (November–February), for populations this similar latitude New Caledonia. releases gametes episodically, multiple times during summer. Assimilation from OTI elsewhere along GBR tropical Pacific revealed that by S. influenced lunar cycle, taking place around new moon This aggregative spawner behavioural change to attain elevated positions dusk prior spawning. After season, remaining gonads are reabsorbed. Spent completely lacked gametes. There was quiescence gonad development winter absence some specimens, indicating aestivation-like period reproduction. By late-winter (August) recovery stage were distinguished initiation gametogenesis, which coincided increasing temperature day length. Our findings contribute understanding consideration future fisheries management protection Vulnerable species, especially respect global trade beche-de-mer.