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Is the Salton Sea fished out?
Politics, tricky ecology make it hard to determine if fewer fish equal fading ecosystem
By Benjamin Spillman
The Desert Sun
September 2, 2003
--------------------------------------------------------------------------------
DESERT SHORES -- It’s another hot, quiet morning on the salt-crusted banks of the Salton Sea when fisherman Ray Garnett eases a pontoon boat into the murky green water.
The well-worn craft that supports Ray’s Guide Service is outfitted with all the gear necessary for a long day at sea.
Fishing poles stand sentry at the front and back of the boat, there’s an aerated tank to keep live bait lively, and stacks of drawers filled with colorful rubber lures Garnett uses to entice corvina to bite his clients’ hooks.
Unfortunately for Garnett, even folks with decades worth of gadgets and knowledge of the sea haven’t been able to find fish for nearly a year.
"It has been worse the last two years than it has ever been," said Garnett, 73, who said he has fished the sea thousands of times since 1955.
"This could be it, we don’t know."
The fisherman’s drought coincides with a depressed fish population that conjures images of the sea’s potential future if water quality continues its slow decline.
Nevertheless, Garnett and his fishing buddy, Newt Wright, 71, toss a couple of lures into the water and watch the lines drift slowly away behind the boat.
Both say the lack of fish raises troubling questions about the health of the sea, but they also suspect the fish will return.
They’re accustomed to what is thought to be a "boom and bust" life cycle for fish in the sea. But like scientists who study the water, they don’t know how long the cycle can continue.
Jack Crayon, a biologist for the California Department of Fish and Game, compared life in the sea to the stock market.
"This could be the Dow Jones Industrial Average," he says, pointing to a chart with jagged lines representing past fish counts. "We are at a very, very low point."
The causes behind the fluctuations, however, are proving as difficult to explain as the concept of a jobless recovery.
"There are plenty of people who have opinions about the fishing. Without data, it is just an opinion," Crayon said. "Just because you don’t catch fish doesn’t mean they are not there."
For all the complaints that the sea has been studied to death -- many from people anxious to jump start restoration projects -- there are few absolute truths.
Among them:
The sea is a terminal body, meaning the only way water escapes is through evaporation. As a result, salts that flow in highly diluted remain and concentrate when the water evaporates.
Salinity levels in recent years have hovered around 44,000 parts per million, about 25 percent higher than the Pacific Ocean. It is thought the Salton Sea fish could survive levels above 50,000 assuming the salt-stressed creatures don’t encounter other environmental pressures.
The sea’s warm water -- 87 degrees when Garnett went fishing -- hosts tremendous levels of algae.
Algae provides food for other creatures higher up the food chain that includes bugs and other tiny, spineless creatures, fish and birds. The algae also sap oxygen from the water that would otherwise be used by fish. A widespread depletion of oxygen in a lake teeming with life can kill large numbers of fish, which also impacts the food chain.
There is heavy political pressure to intercept about 30 percent of water that flows into the sea -- mostly crop irrigation runoff from the Imperial Valley -- for water users in San Diego and the Coachella Valley. The pressure means it is unrealistic to assume the sea’s delicate ecological balancing act can be maintained. There are several proposals to shrink and stabilize the sea, but some are estimated to cost more than $2 billion. Some of the money, however, could be recouped by selling water.
The confluence of complicated, misunderstood ecology at sea level and intense political angling for the water make it nearly impossible to predict whether any one environmental crisis represents the demise of the Salton Sea fishery.
"I’m not even willing to speculate, nobody is," said Doug Barnum, the scientist who coordinates research at the Salton Sea Science Office. "It truly is one of those mysteries."
Barnum said the apparent instability of the fish population suggests "they may be right at the edge of their physical tolerance," and that doesn’t bode well for the rest of the ecosystem.
"The overall state of the sea goes hand in hand with the fish," Barnum said. "There is something that has gone wrong. We just don’t know what it is."
There are some nascent efforts to pinpoint the causes of the sea’s problems. Scientists from the firm Bechtel Nevada, the company that runs the government’s famed Nevada Test Site, recently concluded a five-day excursion to the Coachella Valley.
They shot aerial, color stereo photographs that will help in charting how algae migrate around the sea.
Following the algae is important because large concentrations will deplete oxygen in the water, creating dead zones that kill fish or drive them away.
The zones, referred to as "green water" by locals, have been widespread this summer, Garnett said. "If (fish) can get out of it, they get out of it," the fisherman said, describing the phenomena. "If they don’t, they get trapped and they die."
An algae map would complement Crayon’s efforts to establish fish population records and provide the sea’s keepers data on emerging trends. So far, there have been three study periods -- 1999, 2002 and 2003 -- using Fish and Game protocol.
The limited data show fish populations are dramatically lower than they were four years ago.
Nets that trapped more than 50 tilapia, nearly 10 croaker and about four corvina per hour in 1999 yielded less than one fish per hour this summer. But scientists haven’t identified a corresponding spike in salinity or any other changes to blame for the decline.
"The things that are problematic with the sea have been problematic for decades," Crayon said. "My gut feeling is there are water quality issues that are the most likely suspect."
There are anecdotal reports that young tilapia are showing up in the water. That would support the notion the fish population could rebound.
The idea rekindles Garnett’s fond memories of a more abundant sea.
"In the late ’60s and early ’70s, you could come out and catch sargo by the washbucket full," he said.
Wright recalled how dramatically another fishing dry spell ended in 1995.
"We had some of the best fishing we ever had after that," said Wright, who first visited the sea on Labor Day in 1956. "This time, we’ll just have to wait and see."
Politics, tricky ecology make it hard to determine if fewer fish equal fading ecosystem
By Benjamin Spillman
The Desert Sun
September 2, 2003
--------------------------------------------------------------------------------
DESERT SHORES -- It’s another hot, quiet morning on the salt-crusted banks of the Salton Sea when fisherman Ray Garnett eases a pontoon boat into the murky green water.
The well-worn craft that supports Ray’s Guide Service is outfitted with all the gear necessary for a long day at sea.
Fishing poles stand sentry at the front and back of the boat, there’s an aerated tank to keep live bait lively, and stacks of drawers filled with colorful rubber lures Garnett uses to entice corvina to bite his clients’ hooks.
Unfortunately for Garnett, even folks with decades worth of gadgets and knowledge of the sea haven’t been able to find fish for nearly a year.
"It has been worse the last two years than it has ever been," said Garnett, 73, who said he has fished the sea thousands of times since 1955.
"This could be it, we don’t know."
The fisherman’s drought coincides with a depressed fish population that conjures images of the sea’s potential future if water quality continues its slow decline.
Nevertheless, Garnett and his fishing buddy, Newt Wright, 71, toss a couple of lures into the water and watch the lines drift slowly away behind the boat.
Both say the lack of fish raises troubling questions about the health of the sea, but they also suspect the fish will return.
They’re accustomed to what is thought to be a "boom and bust" life cycle for fish in the sea. But like scientists who study the water, they don’t know how long the cycle can continue.
Jack Crayon, a biologist for the California Department of Fish and Game, compared life in the sea to the stock market.
"This could be the Dow Jones Industrial Average," he says, pointing to a chart with jagged lines representing past fish counts. "We are at a very, very low point."
The causes behind the fluctuations, however, are proving as difficult to explain as the concept of a jobless recovery.
"There are plenty of people who have opinions about the fishing. Without data, it is just an opinion," Crayon said. "Just because you don’t catch fish doesn’t mean they are not there."
For all the complaints that the sea has been studied to death -- many from people anxious to jump start restoration projects -- there are few absolute truths.
Among them:
The sea is a terminal body, meaning the only way water escapes is through evaporation. As a result, salts that flow in highly diluted remain and concentrate when the water evaporates.
Salinity levels in recent years have hovered around 44,000 parts per million, about 25 percent higher than the Pacific Ocean. It is thought the Salton Sea fish could survive levels above 50,000 assuming the salt-stressed creatures don’t encounter other environmental pressures.
The sea’s warm water -- 87 degrees when Garnett went fishing -- hosts tremendous levels of algae.
Algae provides food for other creatures higher up the food chain that includes bugs and other tiny, spineless creatures, fish and birds. The algae also sap oxygen from the water that would otherwise be used by fish. A widespread depletion of oxygen in a lake teeming with life can kill large numbers of fish, which also impacts the food chain.
There is heavy political pressure to intercept about 30 percent of water that flows into the sea -- mostly crop irrigation runoff from the Imperial Valley -- for water users in San Diego and the Coachella Valley. The pressure means it is unrealistic to assume the sea’s delicate ecological balancing act can be maintained. There are several proposals to shrink and stabilize the sea, but some are estimated to cost more than $2 billion. Some of the money, however, could be recouped by selling water.
The confluence of complicated, misunderstood ecology at sea level and intense political angling for the water make it nearly impossible to predict whether any one environmental crisis represents the demise of the Salton Sea fishery.
"I’m not even willing to speculate, nobody is," said Doug Barnum, the scientist who coordinates research at the Salton Sea Science Office. "It truly is one of those mysteries."
Barnum said the apparent instability of the fish population suggests "they may be right at the edge of their physical tolerance," and that doesn’t bode well for the rest of the ecosystem.
"The overall state of the sea goes hand in hand with the fish," Barnum said. "There is something that has gone wrong. We just don’t know what it is."
There are some nascent efforts to pinpoint the causes of the sea’s problems. Scientists from the firm Bechtel Nevada, the company that runs the government’s famed Nevada Test Site, recently concluded a five-day excursion to the Coachella Valley.
They shot aerial, color stereo photographs that will help in charting how algae migrate around the sea.
Following the algae is important because large concentrations will deplete oxygen in the water, creating dead zones that kill fish or drive them away.
The zones, referred to as "green water" by locals, have been widespread this summer, Garnett said. "If (fish) can get out of it, they get out of it," the fisherman said, describing the phenomena. "If they don’t, they get trapped and they die."
An algae map would complement Crayon’s efforts to establish fish population records and provide the sea’s keepers data on emerging trends. So far, there have been three study periods -- 1999, 2002 and 2003 -- using Fish and Game protocol.
The limited data show fish populations are dramatically lower than they were four years ago.
Nets that trapped more than 50 tilapia, nearly 10 croaker and about four corvina per hour in 1999 yielded less than one fish per hour this summer. But scientists haven’t identified a corresponding spike in salinity or any other changes to blame for the decline.
"The things that are problematic with the sea have been problematic for decades," Crayon said. "My gut feeling is there are water quality issues that are the most likely suspect."
There are anecdotal reports that young tilapia are showing up in the water. That would support the notion the fish population could rebound.
The idea rekindles Garnett’s fond memories of a more abundant sea.
"In the late ’60s and early ’70s, you could come out and catch sargo by the washbucket full," he said.
Wright recalled how dramatically another fishing dry spell ended in 1995.
"We had some of the best fishing we ever had after that," said Wright, who first visited the sea on Labor Day in 1956. "This time, we’ll just have to wait and see."
