▁a ▁result ▁of ▁an ▁accident al ▁introduction ▁in ▁ 1 9 9 5 ▁when ▁an ▁aqu arium ▁population ▁was ▁liber ated ▁into ▁the ▁sea ▁at ▁Wood bridge ▁due ▁to ▁a ▁concern ▁over ▁their ▁care ▁during ▁a ▁hol iday ▁period . ▁It ▁is ▁found ▁on ▁rock , ▁hiding ▁under ▁stones ▁and ▁in ▁cre v ices , ▁in ▁the ▁inter tid al ▁zone ▁and ▁in ▁very ▁shall ow ▁water ▁( under ▁ ▁deep ). ▁ ▁E col ogy ▁This ▁star fish ▁fe eds ▁on ▁the ▁micro b ial ▁and ▁alg al ▁film ▁found ▁on ▁the ▁surface ▁of ▁rocks . ▁It ▁does ▁this ▁by ▁ever ting ▁( push ing ▁out ) ▁its ▁st om ach ▁through ▁its ▁mouth , ▁and ▁dig est ing ▁the ▁film ▁in ▁situ . ▁It ▁fe eds ▁at ▁night ▁and ▁on ▁over cast ▁days . ▁ ▁P . ▁viv ip ara ▁is ▁a ▁herm aph rod ite , ▁each ▁individual ▁typically ▁having ▁six ▁to ▁eight ▁female ▁g on ads ▁and ▁a ▁single ▁male - type ▁g on ad . ▁The ▁se ast ars ▁mostly ▁self - fer til ise , ▁but ▁it ▁is ▁likely ▁that ▁some ▁cross ▁fert il isation ▁occurs . ▁The ▁emb ry os ▁and ▁ju ven iles ▁are ▁bro oded ▁within ▁the ▁mother ' s ▁body ▁cav ity . ▁They ▁are ▁present ▁in ▁various ▁sizes , ▁and ▁usually ▁leave ▁the ▁protect ive ▁environment ▁to ▁live ▁independently ▁by ▁the ▁time ▁they ▁are ▁ 3 0 % ▁of ▁the ▁parent ' s ▁diameter . ▁They ▁emer ge ▁through ▁g on op