Drought May Mean The End For Some Native Fish
The drought in California is taking a heavy toll on native fish. Some experts fear if the drought lasts much longer, it may be a death knell for some species. As Amy Quinton reports from Sacramento, the Delta smelt is likely headed toward extinction.
A hydraulic winch pulls in a giant net on a California Department of Fish and Wildlife boat. Since 2002, the Department has surveyed the number of spawning Delta smelt. The Sacramento San Joaquin Delta is the only place in the world to find the threatened three inch fish. Lately, it hasn’t been easy, says environmental scientist Lauren Damon.
Damon: “Numbers are down this year. So the March survey we caught six. The April survey we caught one. Those catches are pretty low. They’re not unprecedented but certainly for our March survey that’s the lowest catch we’ve ever experienced.”
We’re on the lower Sacramento River, south of Rio Vista. The drought is apparent with the first trawl. A lack of freshwater flowing downriver has saltwater species moving further inland. The trawl nets dozens of anchovies and pacific herring. As we move north into the Sacramento Deep Water Ship Channel, crews immediately know they’ve caught a Delta smelt.
Quinton: “SO WHAT DOES THAT MEAN THAT IT SMELLS LIKE CUCUMBERS?
Damon: “That means there is Delta smelt in there. “So there is four adult Delta smelt in here.”
In previous years, the catch has been in the hundreds, sometimes more than a thousand. One the boat today, they netted just five.
UC Davis fish biologist Peter Moyle is sampling fish on a boat in the Suisun Marsh, on the western edge of the Delta. He says the smelt is close to extinction.
Moyle: “Whether a small number of fish can continue the species is a good question.”
He’s been monitoring for more than 30 years.
Moyle: “Nice catch of fish, almost all natives so far., no smelt either. But you have to realize when I started out they were a fairly common fish in the marsh.”
Moyle says smelt populations have plummeted.
Moyle: “The drought just seems to have made things worse, less freshwater to dilute contaminants, warmer temperatures in the water, cause there is less cold water coming down the system, all these things are taking place simultaneously “
Delta smelt aren’t the only victims, other threatened species are struggling. Long fin smelt populations are the second lowest ever recorded. Ninety-five percent of last year’s brood of winter-run Chinook salmon died. State water regulators and fish agencies conceded that they were wrong in the way they managed the state’s water system last year. Stafford Lehr is the Chief of Fisheries with the California Department of Fish and Wildlife.
Lehr: “I think the awareness of what happened last year, has heightened the sensitivity, you just can’t turn the knobs and set it and walk away and expect everything to be fine and everybody understands we have to be more aggressive in responding.”
Lehr says the Department has begun using high tech sensors and satellites to monitor fish and water quality. It’s taken emergency actions, even moving fish into captivity to try to save species. But Jon Rosenfield, a conservation biologist with the Bay Institute says the state can’t continue operate the water system in the same way and expect different results.
Rosenfield: “ The question for me is, how many more years of drought do we need to realize that the way we use water is unsustainable.”
Rosenfield says while these threatened fish have survived drought before, he questions the likelihood now.
Rosenfield: “They don’t deal with, in a drought, taking out more than 50 percent of the water, that’s just an extraordinary situation that has not occurred naturally.”
Department of Fish and Wildlife Chief Stafford Lehr says it’s difficult to balance the needs of a growing state with a limited amount of water.
Lehr: “We do not want this on our watch, the extinction of a species.”
Some might say the small population of Delta smelt isn’t worth saving, but Peter Moyle says its disappearance would signal a greater loss.
Moyle: “If we let the smelt go, we’re essentially saying we don’t need a really functioning estuary, and California is going to be losing something very special if that fish disappears.”