but as reporter dan brekke found, relief may be temporary. >> reporter: the first big rains of the season draw coho salmon back to lagunitas creek. with only a few hundred adult coho returning here annual to spawn these fish are fighting for survival. now they face a new threat, california's drought. to find out how the fish are doing i met up with greg andrew, a fish biologist with the marin municipal water district, and his intern rosa albanese. >> we've got waders for you. you can put these on, keep you dry. >> they let me join them on a survey to track fresh spawning activity in lagunitas creek, one of the last strongholds for wild coho salmon on the central coast. >> right away we've got two nest sites where the female has laid her eggs and the male has fertilized those. >> i gave greg a hand measuring the spawning nest site. >> that's good. doesn't have to be exactly there but pretty close. 7.2. >> normally the coho in the lagunitas watershed finish spawning in mid-january. but the drought has changed the fish's behavior pushing the spawning season well into february. >> what that t