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Massive fish kill seen in Hood Canal - Low-oxygen problems continue to injure the waterway's sea life Christopher
Dunagan June 12, 2003 Hood Canal, WA - An estimated 50,000 dead perch found Tuesday near Potlatch provide evidence that Hood Canal is still plagued by deadly low-oxygen problems.
"The tide was going out, and fish were up on the beach," said Jouper, who works at the nearby George Adams Salmon Hatchery. "They weren't a solid (mass) but were pretty close to each other, about every couple of feet," he said. Others were floating far offshore. This type of fish kill, probably from oxygen starvation, has occurred before in Hood Canal. It's not the same as the widespread low-oxygen conditions that affected much of the canal last fall, said Larry Altose, spokesman for the Washington Department of Ecology. Still, there is evidence that Hood Canal marine life could be headed for another bad year. Warm weather followed by cold weather the past week might have caused a pocket of low-oxygen water to rise out of the depths, Altose said. The short-lived event, known as a "turnover," can suffocate fish that get in the path of the oxygen-depleted water. Jouper said he counted among the dead fish three bottom-dwelling sculpins, an eel and several tiny crabs, as well as the thousands of perch. "We had an experience like this eight or 10 years ago in the Hoodsport area," he said. Like the previous incident, fishermen in the area reported that the water had turned a chocolate brown from an algae bloom triggered by sunlight. Jan Newton, an oceanographer with the Department of Ecology, said it's too early to tell whether the deadly conditions that affected much of Hood Canal last fall will be repeated. Water samples taken in May, however, revealed oxygen levels even lower than at the same time last year. "It's worse than last year," Newton said. "Whether that will matter by the time we get to fall is hard to say. My suspicion is that it will." Last October and November, bottom fish were forced to the surface to find enough oxygen. Rockfish, normally sedate, were moving rapidly. Frisky shrimp barely were moving at all. Slow-moving sea cucumbers -- red, elongated creatures that live on the bottom -- were either dead or climbing over each other to get enough oxygen. Based on May's findings, oxygen levels throughout most of the canal still are considered safe, Newton said. "It's not a bad concentration right now," she said. "But at mid-depth this is the worst or equals the worst that we've ever seen (for this time of year)." The weather between now and fall could make a big difference, she said. Continued sunlight paired with nutrients flowing into Hood Canal from natural and man-made sources could push the oxygen levels to record lows this fall when low-oxygen water flows in from the ocean. Low-oxygen conditions in the fall are believed to be caused by the growth and death of algae. Sunlight and nutrients trigger an explosive growth of the tiny organisms, which then die and sink to the bottom, where decomposition consumes available oxygen. Hood Canal suffers more than most other waterways because of a complex set of factors, including poor mixing of deep waters, low flushing to the ocean and good growing conditions for algae. Nobody knows how much man-made nutrients, such as lawn fertilizers and septic systems, add to the problem, she said. Some people already are suggesting that any reduction in man-made nutrients -- such as avoiding fertilizers this summer -- could be worthwhile. |