By Bill Sheets Herald Writer
OAK HARBOR — A sudden population explosion of Canada geese at a lake in Deception Pass State Park has prompted the state to take action.
The geese’s feces are making Cranberry Lake unsafe for swimmers and damaging the habitat for wildlife, state officials say.
The state has begun using non-lethal methods to chase off the geese, said Eric Watilo, a field operations manager for the state parks department in Burlington.
State park officials plan to use dogs to haze the birds; fence off the lake’s shoreline; set up fake coyotes, called “cutouts,” and spray the lawns with a sour-tasting extract, Watilo said.
If this doesn’t work, the U.S. Department of Agriculture would be called in during the summer to euthanize the geese. Watilo said he doesn’t know what method would be used.
The number of geese at Cranberry Lake ballooned last summer, Watilo said. While some have left for the winter, a core population remains, and it’s expected to grow again in the summer.
Recent tests of the lake by Island County health officials showed it does not meet health standards for public swimming beaches. Saltwater beaches at the park have not been affected, Watilo said.
Goose feces contain salmonella, giardia and cryptosporidium, according to state parks officials — all of which can make humans seriously ill. Canada geese also are known to host the parasite that causes “swimmer’s itch,” state officials said.
Canada geese are non-native to coastal Washington, according to the state. Historically, these geese migrated through the area, but over time they have made themselves at home due to favorable conditions created by landscaping and lawns.
Geese are fond of lakes, and if present in large numbers their feces fills the water with phosphates, nitrates and organic nutrients that promote an abundant growth of algae. As the algae dies and decays, it depletes the dissolved oxygen supply. This can kill fish and cause blooms of blue-green algae, or cyanobacteria, some of which produce toxins or poisons that can kill pets, waterfowl and other animals, in addition to causing severe illness in humans, according to the state parks department.
Large numbers of geese in the area also pose a risk to aircraft at the naval base on the island, parks officials said.
Deception Pass State Park staff hosted a public meeting recently to discuss the plan for the geese, which is being deployed in other parts of the state, officials said.
Bill Sheets: 425-339-3439; firstname.lastname@example.org.