Lagunitas Creek is one of the few places you can still find wild Coho salmon. At least for now.
"We're down the last couple hundred fish returning. At one time, there were thousands of fish," said Todd Steiner, Director at SPAWN - The Salmon Protection and Watershed Network.
The government has labeled them critically endangered and given grants to conservation groups for projects like this one.
"They're funneled into this net, then into this pipe, and into our trap box over here," Steiner said.
He's the head of a group called SPAWN that's counting and weighing the young salmon swimming downstream, then releasing them to see how many come back three years later to lay eggs. Or they were, until a few days ago.
"Someone basically came in, they smashed our net box over here into a million pieces, they pulled all the piping out of the way, they bent all the rebars, and they literally stole the net," Steiner said.
Over a thousand dollars in damage. And the whole thing was caught on camera. The only problem -- you can't see the vandal's face.
SPAWN is offering a $500 reward to whomever can point the finger at the culprit.
"This is someone who had a major axe to grind," Steiner said.
So who would want to ruin a project like this? Well, the answer could be a lot of people. You see, although SPAWN's mission may be a noble one, they've become hated by some of the landowners who want to build houses along this creek.
"This is one of several fliers that have been posted around the valley anonymously," Steiner said.
Steiner says he's been the target of threats and hate mail since his group started lobbying for restrictions on building near the creek.
"If we continue to develop right up to the edge of the stream, as we've done in the past, and continue to make these mistakes, there's no questions these fish are gonna go extinct," he said.
The research is back up and running with a major gap in the data.
"It really breaks up our sampling period, and it jeopardizes the results of the entire season," said SPAWN Conservation Science Director Alex Hearn.
But the vandal could pay for that. If endangered salmon were killed, that's a federal offense and could mean jail time.