California's third year of drought has worsened the already dire outlook for endangered coho salmon, as coastal creeks used for spawning dwindle into disconnected pools where fish get trapped and die.
On a hot summer afternoon about 40 miles north of San Francisco, a group armed with fishing nets and buckets was on a rescue mission. They slogged through muddy pools, the last vestiges of once-flowing Arroyo Creek, trying to find stranded coho and threatened steelhead trout.
So far this summer, these fish rescuers in Marin County have found no coho, an ominous sign for a species struggling to survive on the West Coast.
"Every year it's like ahhh! Where are they?," said biologist Chris Pincetich, who organizes the rescues for the Salmon Protection and Watershed Network, or SPAWN.
California's drought has increased wildfires, caused an economic crisis in the state's agriculture industry and a shrinking water supply. But experts say three years of arid weather may also be the final blow for coho, already reeling from pollution and population growth.
Federal fisheries regulators say the disappearance of coho salmon in Marin County is not an isolated incident, and that studies find they are vanishing along the state's central and northern coast. Coho live in coastal streams where they mature before moving to the ocean, and then back to freshwater to reproduce.
'Alarmingly low numbers'
"There are definitely alarmingly low numbers of adult returns and spawning decreases," National Marine Fisheries Service fishery biologist Jeffrey Jahn said. "And the fish that are produced by the few coho who do make it back have to deal with these drought conditions, which is affecting the status of the species."
In 2004, SPAWN fish rescuers saved 120 coho from the small tributaries that feed Marin County's Lagunitas Creek. The numbers rescued have been declining ever since to zero.
Coho salmon, known for their hooked mouths and bright red sides, usually live for a year or two in these coastal creeks and streams before moving out to sea.
But Pincetich and other biologists who study coho say scale samples taken from the salmon returning to the ocean from Lagunitas Creek in recent years tell a startling tale. The scales aged the coho at two-and-a-half years old.
"It means the coho didn't go out after that first year, and instead resided in freshwater for another year," said Jahn. "When the fish wanted to leave, they couldn't because the creek wasn't connected."
Because coho are endangered, federal regulators are tasked with devising a plan to help the fish rebound. The recovery plan for coho is overdue, but the Fisheries Service said it should be completed by the end of September. The coho "draft recovery plan" will show how overdevelopment, a warming ocean, pollution and other factors all play a part in the decline of coho, steelhead and other fish that for centuries were a mainstay in coastal waters.
Fish moving operation
Meanwhile, the fish rescuers at SPAWN continue trying to save as many fish as they can.
One recent afternoon men, women and children volunteers used nets to gently snatch steelhead smolts out of disconnected pools created by drying creeks and streams. They moved the fish down to a freely flowing waterway to give them a better chance at survival.
Ayden and Rachel Nathan of San Jose brought their sons, Michael, 11, and Benjamin, 8, to help. The boys waded in the cool, shin-deep water, swaying their nets back and forth.
"I got one!" an excited Benjamin exclaimed.
It was a steelhead. Paola Bouley, SPAWN's conservation director, palmed the small fish and set it into a bucket with a buzzing air pump clipped to the side.
While no coho were found, the group netted about 20 young steelheads, which also spawn in these waters and are a federally threatened species.
They released the small fish into San Geronimo Creek, which flows to the sea.