Algae bloom scuttles Free Fishing Weekend
A blue-green algae bloom at Lost Creek Lake may or may not be toxic to people and pets, but it proved fatal to a Free Fishing Weekend event planned there Saturday.
The Oregon Health Authority on Tuesday afternoon issued an advisory against water contact at the lake — the first advisory issued this year in Oregon — after the discovery of a large bloom of cyanobacteria at Jackson County's largest water body, which prompted Oregon State Parks officials to cancel the annual fishing event.
Water tests showed more than 3.2 million cells per milliliter of Anabaena flos-aquae, a cyanobacteria that has bloomed regularly in late spring at the Rogue River reservoir 30 miles north of Medford, according to the U.S. Army Corps of Engineers, which operates the lake.
Anabaena flos-aquae can produce potentially dangerous toxins, particularly when the bloom dies off. But not all blooms are toxic. The threshold for a public-health advisory in Oregon is 100,000 cells per milliliter.
State parks officials canceled the event Wednesday, but the Oregon Department of Fish and Wildlife still plans to release 5,250 rainbow trout there this week.
During advisories, people and pets are warned to avoid all water contact, but compliance is voluntary. Anglers are encouraged to practice catch-and-release fishing during advisories.
People who eat fish from algae-tainted waters should remove all fat, skin and organs before cooking, because toxins can collect there. People should not eat crayfish or freshwater shellfish taken from infested lakes during an advisory.
Boating and fishing are considered safe so long as boat speeds do not create excessive water spray, according to health officials.
Toxins cannot be filtered by standard camp filters or by boiling the water. In-home filtering systems cannot cleanse the water, though public treatment plants can reduce algae toxins through filtration and disinfection.
Exposure to toxins can produce symptoms of numbness, tingling and dizziness that can lead to difficulty breathing or heart problems, and require immediate medical attention. Symptoms of skin irritation, weakness, diarrhea, nausea, cramps and fainting should also receive medical attention if they persist or worsen.
Children and pets are at increased risk for exposure because of their size and level of activity.
The public will be advised when the concern no longer exists.
Not all blue-green algae strains produce toxins dangerous to people or pets, and not all blooms release toxins.
No confirmed human illnesses have been tied directly to an algae outbreak in Oregon. However, at least four dogs have died in recent years from toxins in water near the Umpqua River near Elkton.
Reach reporter Mark Freeman at 541-776-4470 or email@example.com.