Cholera outbreak in Redwood Shores pond kills 185 ducks in one week
Citing a serious threat to wildlife, a wastewater treatment agency is draining a Redwood Shores pond popular with bird watchers where an outbreak of avian cholera has killed about 185 ducks in one week.
The disease does not pose a threat to humans, a U.S. Fish and Wildlife Service official said in an announcement sent out Friday by the South Bayside System Authority.
Although officials aren’t certain how the bacteria that causes the disease entered the pond located off Radio Road, they suspect birds that flew in from the East Bay transmitted it, said Daniel Child, the authority’s general manager. He said there’s been an avian cholera outbreak in a Hayward regional park.
The water in Redwood Shores’ man-made pond is usually kept fresh by a flow of recycled water from South Bayside’s treatment plant just east of it. The authority started draining the pond Friday to disinfect it.
The pond is expected to remain dry for a couple of months or longer, Child said Friday.
“Water and soil can keep the bacteria alive, so we need the soil to dry out,” Child said. “If it rains, the rainwater starts the bacteria issue all over again.”
A local birdwatcher first noticed some dead birds at the pond last month and contacted U.S. Fish and Wildlife Service at the Don Edwards Preserve in Fremont, Child said. A subsequent inspection revealed dead ducks floating in the water and along the pond’s land edges. Once birds contract the disease, “they only live for six to 12 hours from the time they get it,” Child said.
The pond was created in 1998 to eliminate dust from the dry dirt that regularly clogged up the facility’s machinery, Child said.
Now it’s a favorite spot for bird watchers because of the multitude of waterfowl and shorebirds that have made it their home.
Los Altos resident Gay Duval, who came out to the pond Friday after hearing about the dying birds, said it’s one of her favorite birding spots, along with the Baylands Nature Preserve in Palo Alto.
“There’s usually hundreds and hundreds of birds here,” Duval said. “I hope it doesn’t go further south. It’s good that they’re doing something proactive now.”
The bird count now appears unusually low, Child said, although he didn’t know whether that’s because of the disease breakout.