brought back to California State University Long Beach. These rays
were then remeasured, weighed, and euthanized via immersion in
seawater ice slurry for 30 min, in accordance with approved CSULB
Animal Welfare Board protocol #212. Blood samples were taken
through cardiac puncture, and blood was placed into heparinized vials
and centrifuged for 5 min at 5000 g. The plasma was removed and
stored at −85 °C until assayed. Testes were removed, weighed, and
placed into 10% neutral buffered formalin for 9 d and transferred to
70% ethanol until paraffin embedding. Seasonal photoperiod was
determined based on sunrise/sunset times for Seal Beach on each
sampling date. Sea surface water temperatures were collected from
the National Data Buoy Center (NDBC) buoy 46230 off of Huntington
Beach (33 °37′23″ N 118 °00′43″ W) and station OHBC1-9410660 off of
San Pedro, CA (33 °43′12″ N 118 °16′18″ W).