A recent study found that active removal of predators in the San Joaquin-Sacramento Delta in California as a way to protect a native and imperiled species may not get the intended results.
In 2015, nearly half of steelhead smolts that began their journey to the ocean at Rock Island Dam on the upper Columbia River did not survive the onslaught of birds that feed on the smolts along the way, according to Blaine Parker, avian predation coordinator at the Columbia River Inter-Tribal Fish Commission.
Since 2015, when the efforts to suppress or eradicate non-native northern pike from Lake Roosevelt began, nearly 13,000 of the voracious fish have been removed from the huge reservoir that backs up behind Grand Coulee Dam on the upper Columbia River.
In an effort to discourage birds from snatching up juvenile salmon below McNary Dam, the U.S. Army Corps of Engineers Walla Walla District has bought a laser.
Two different anglers on two different waterbodies, but both in the anadromous zone of the Columbia River basin and both on the same day – July 17, 2017 – say they saw one of the most feared invasive predators in the basin, a northern pike. But, their alleged sightings were quickly debunked … by science.
Northern pike were promoted to a short list of the most unwanted invasive species in the state of Washington on Friday by the state’s Fish and Wildlife Commission.
For the most part, the double-crested cormorants that abandoned one of the largest cormorant colonies in the world, located at East Sand Island in the lower Columbia River estuary, simply moved a couple of miles upstream to the Astoria-Megler Bridge, according to a study in process.
As efforts continue to curb the proliferation of northern pike in the Columbia River Basin, the state of Washington and co-management agencies are pursuing additional funding and flexibility to respond to the voracious predators entering the “anadromous zone” downstream from Grand Coulee Dam.
NOAA Fisheries has released a draft plan for public comment to remove and kill as many as 416 California and Steller sea lions each year in a 180 mile stretch of the Columbia River from just downstream of Bonneville Dam at river mile 112 upstream to McNary Dam at river mile 292.