The pre­miere of “Into the Deep with Ele­phant Seals,” a QUEST TV pro­gram, fol­lows UC Santa Cruz marine biol­o­gist Dan Costa as he uncov­ers how north­ern ele­phant seals behave at sea. Every win­ter, the seals migrate to the NRS’s Año Nuevo Island Reserve and adja­cent beaches on the San Mateo County shore to breed. Costa and col­leagues take advan­tage of their brief time on land to glue GPS track­ing tags and other instru­ments to the seals’ fur. The result­ing infor­ma­tion has lit­er­ally rewrit­ten the book on these ath­letes of the ocean, which can hold their breath for two hours and dive a mile below the surface.

Watch QUEST TV this Wednes­day, May 4 at 7:30 pm on KQED 9 & KQED HD on Com­cast 709.

Or, watch it online.

Read more about Dan Costa’s work track­ing marine ani­mals with satel­lite tags.