Massive fish die-off forecast
|
Normally, the winter gives oxygen-starved waterways a chance to recover, as oxygen-sucking algae disappear and new oxygen-rich ocean water blends with the old. But not this time.
Tests by the state Department of Ecology (DOE) in the spring showed that oxygen levels in the deeper waters of Hood Canal stayed critically below average.
"The outlook doesn't look good," said Jan Newton, a University of Washington professor and DOE oceanographer. "This problem is not getting better, it's getting more severe. And we really need to step up our attention to it."
Because it is so narrow and deep, Hood Canal always has been slower than other parts of Puget Sound in replenishing itself with oxygen. But in part because it has been so critically low for at least two years, it started the winter with a deep deficit to overcome.
A year ago this week, more than 50,000 suffocated shiner perch washed up at Potlatch in Mason County. The previous spring, bottom fish were seen gasping at the surface like goldfish whose bowl water hadn't been changed.
For the past three years, Hood Canal has remained closed to fishing for most bottom fish, including halibut, lingcod and herring.
The situation at Hood Canal got so bad that Gov. Gary Locke last winter gave a Puget Sound Action Team $25,000 in emergency funds to study the problem, and a budget has grown to more than $600,000 to pay for programs to try to fix the problems.
Algae blooms in the canal have been identified as the chief culprit. When algae die and decompose, they sponge oxygen out of the water in deadly quantities.
Nitrogen in the water causes the abnormally large blooms. A study released last month said that leaking septic tanks of homes along the canal are the chief source of nitrogen there. Other sources include storm-water runoff and cattle manure that is allowed to seep into streams and rivers that flow to the canal.
The report recommends building a sewer system for Hood Canal residents and enacting programs to curb runoff. Fishermen who discard dead chum salmon into the canal also have been asked to find other ways to get rid of the carcasses.
The Puget Sound Action Team has money ranging from $10,000 to $100,000 a project for businesses, schools, local governments or tribes that come up with specific plans. In the meantime, biologists were pleading with homeowners to fix their septic tanks and curb runoff from their lawns.
"Humans do have that ability to tip the balance," Newton said. "And we could be tipping the balance without that much extra effort."
|