ance ▁where ▁they ▁were ▁turned ▁into ▁l ighth ouse ▁stations , ▁or , ▁in ▁the ▁case ▁of ▁Al cat raz , ▁a ▁prison . ▁ ▁Western ▁g ull s ▁are ▁very ▁ag gress ive ▁when ▁def ending ▁their ▁territ ories ▁and ▁consequ ently ▁were ▁per sec uted ▁by ▁some ▁as ▁a ▁men ace . ▁The ▁autom ation ▁of ▁l ighth ouses ▁and ▁the ▁closing ▁of ▁Al cat raz ▁Pr ison ▁allowed ▁the ▁species ▁to ▁rec laim ▁parts ▁of ▁its ▁range . ▁They ▁are ▁currently ▁vulner able ▁to ▁clim atic ▁events ▁like ▁El ▁Ni ño ▁events ▁and ▁oil ▁sp ills . ▁ ▁Western ▁g ull s ▁have ▁become ▁a ▁serious ▁n uis ance ▁to ▁the ▁San ▁Francisco ▁Gi ants ▁baseball ▁team . ▁Th ous ands ▁of ▁g ull s ▁fly ▁over ▁AT & T ▁Park ▁in ▁San ▁Francisco ▁during ▁late ▁inn ings ▁of ▁games . ▁They ▁sw arm ▁the ▁field , ▁def ec ate ▁on ▁fans , ▁and ▁after ▁games ▁eat ▁le f to vers ▁of ▁stad ium ▁food ▁in ▁the ▁seats ; ▁how ▁the ▁birds ▁know ▁when ▁games ▁are ▁about ▁to ▁end ▁is ▁unknown . ▁The ▁g ull s ▁left ▁while ▁a ▁red - ta iled ▁ha w k ▁visited ▁the ▁park ▁in ▁late ▁ 2 0 1 1 , ▁but ▁returned ▁after ▁the ▁ha w k ▁disappeared . ▁Federal ▁law ▁prohib its ▁shooting ▁the ▁birds , ▁and ▁h iring ▁a ▁fal con er ▁would ▁cost ▁the ▁Gi ants ▁$ 8 0 0 0 ▁a ▁game . ▁ ▁In ▁media ▁The ▁western ▁g