Fleeing cull, refugee cormorants settled on the Astoria-Megler Bridge. Now guano threatens the bridge––and killing cormorants did not save salmon
PORTLAND, Oregon––Eight years after massacring 5,576 double-crested cormorants and smashing 6,181 cormorant nests at East Sand Island, ostensibly to protect 12 million migrating salmon smolt per year, the U.S. Army Corps of Engineers and allied agencies are grudgingly admitting it was all a stupid mistake, harmed the salmon more than it helped, and urgently needs to be undone.
The admission that cormorants need to be restored to East Sand Island, however, is coming not on behalf of the birds, though the Columbia River salmon runs and double-crested cormorants are both federally protected species, but on behalf of the Astoria-Megler Bridge.
The longest continuous steel truss bridge in North America, completed in 1966, the Astoria-Megler Bridge crosses the lower Columbia River from Oregon to Washington state. More than 7,300 vehicles per day traverse the bridge, or as many as 2.7 million per year.
Following the cormorant killing in 2015, USDA Wildlife Services gunners hired by the U.S. Army Corps of Engineers shotgunned another 2,400 cormorants and destroyed another 1,000 cormorant nests at East Sand Island in early 2016, until in May 2016, more than 17,000 cormorants fled East Sand Island in a single day, leaving their eggs and nests behind.
About 1,700 cormorant refugees found new nesting habitat on the lower girders of the Astoria-Megler Bridge, previously used by no more than a few hundred cormorants and some gulls.
Since then, the Astoria-Megler Bridge nesting colony has approximately doubled.
Now cormorant guano has become a potential threat to the structural integrity of the Astoria-Megler Bridge, requiring the Oregon and Washington departments of transportation to accelerate their maintenance and repainting cycles.
That costs serious money, and often requires closing one of the two Astoria-Megler Bridge traffic lanes.
Bridge cormorants eat more salmon smolts than the island cormorants did
The cormorants have also found the lower girders of the Astoria-Megler Bridge an excellent diving platform from which to ambush salmon smolt.
Though there are now far fewer cormorants along the lower Columbia River than in 2015, the survivors are eating far more salmon than the lost East Sand Island nesting colony ever did.
Oregon Department of Fish & Wildlife avian predation biologist James Lawonn reported in February 2019 that the cormorant massacres at East Sand Island not only did not save any salmon or steelhead from predation in 2015 through 2017, but may have tripled predation losses.
Killing the bridge cormorants is not recommended
Culling the Astoria-Megler Bridge cormorants might be expected to be the next recommendation of supposed salmon-and-bridge-saving bureaucrats.
However, a 250-page report published on November 7, 2023 indicates that those bureaucrats are now agreed that killing the Astoria-Megler Bridge cormorants would not be a viable solution.
The report was commissioned by the Oregon and Washington departments of transportation, the Oregon Department of Fish & Wildlife, the U.S. Army Corps of Engineers, and the Northwest Power & Conservation Council.
As the report explains, the Columbia River channel narrows, moving upstream from the saltwater estuary where it meets the Pacific Ocean. Upstream, in fresh water, the the number and variety of fish other than salmon and steelhead available to predators diminishes.
Pushing cormorants upstream makes matters worse
Cormorant predation on salmon accelerated when the nesting cormorants were driven upstream from East Sand Island, a favorable nesting habitat for cormorants and Caspian terns accidentally created in 1983 when the Columbia River mouth was dredged to facilitate ship traffic.
Massacring the Astoria-Megler Bridge cormorant nesting colony would likely have the effect of forcing the cormorants even farther upstream, into habitat with even fewer menu choices.
The greater the predation on salmon smolt along the Columbia River, the greater the political pressure is on the Northwest Power & Conservation Council to decommission and remove some of the many dams that block salmon from spawning habitat along Columbia River tributaries.
Bob Sallinger warned them
The public face of Portland Audubon for 30 years before becoming executive director of Bird Conservation Oregon, Bob Sallinger warned many times that the cormorant killing in 2015-2016 would not save endangered salmon runs.
Sallinger cautioned that the cormorant killing could have cataclysmic unforeseen consequences in an unsuccessful 2015 lawsuit, based on a suppressed and ignored study by U.S. Fish & Wildlife Service biologist Steve Haeseker.
Allies in that fight included Travis Williams of Willamette Riverkeeper, Dan Rohlf of the Earthrise Law Center, and Kelly Peterson, regional representative for the Humane Society of the United States.
SHARK couldn’t save cormorants either
Showing Animals Respect & Kindness founder Steve Hindi brought a boat and a video documentation team west from Illinois to document the massacre in 2015, after discovering that the winds around the mouth of the Columbia River are far too strong to permit the use of drones.
The presence of cameras did not stop the cormorant killing either.
Now, said Salinger, Williams, Peterson, and Rohlf in a December 18, 2023 joint media release, “Bird Conservation Oregon, the Humane Society of the United States, and Willamette Riverkeeper are cautiously supporting a recommendation by a study team convened by Oregon Department of Transportation to restore the cormorant colony on East Sand Island,” but are “urging caution as this process moves forward.
“Both exciting & heartbreaking”
“Given the documented declines in double-crested cormorant populations as a result of prior lethal control activities by government agents on East Sand Island,” the joint media release said, “it is essential that any lethal control of either adult cormorants or active nests during the relocation process be kept to an absolute minimum, and that the viability of re-establishment efforts on the East Island be documented to the greatest degree possible before hazing activities are initiated on the Astoria-Megler Bridge” to forcibly motivate the cormorants now there to move.
“This recommendation is both exciting and heartbreaking,” pronounced Sallinger. “Returning cormorants to East Sand Island is the right decision, but it also shows that the wanton slaughter of cormorants on East sand Island by our federal government was entirely unnecessary and misguided.”
East Sand Island was largest cormorant colony west of the Rockies
Recalled Sallinger, “The double-crested cormorant nesting colony on East Sand Island was once the largest west of the Rocky Mountains, with more than 30,000 birds making up approximately 40% of the double-crested cormorant population in the western United States.”
The 2015-2016 cormorant massacre, the joint media release recounted, was supported by the U.S. Fish & Wildlife Service and the National Marine Fisheries Service.
It was supposed to have been a three-year program, culminating with destroying much of the East Sand Island cormorant nesting habitat “by bulldozing it into the [Columbia River] estuary,” the joint media release said, but was halted after the May 2016 cormorant colony collapse.
Restoration project to begin “in 2024 or 2025”
“Conservation and animal welfare groups strongly opposed the slaughter of cormorants on East Sand Island,” the joint media release continued, “arguing that it could put cormorant populations into serious decline,” as it did, “move cormorants to locations where they would potentially consume more salmon than they do on East Sand Island, and potentially cause them to relocate onto the nearby Astoria-Megler Bridge where they could cause damage to the bridge and be hazards to motorists.
“Every single one of those predictions has sadly proven to be correct.”
Rebuilding East Sand Island to attract cormorants and trying to coax them downstream, away from the bridge, “will likely begin in 2024 or 2025,” the joint media release finished.
East Sand Island was best place for nesting colony, prof told U.S. Army Corps of Engineers
Restoring cormorants to East Sand Island will affirm the perspective of Oregon State University wildlife ecology professor Dan Roby, who was hired by the U.S. Army Corps of Engineers to study the potential effects of rousting cormorants from East Sand Island before the 2015-2016 killing, but whose advice was ignored.
“If there is a place in the Columbia River estuary where it would be best for cormorants to nest – and by best, I mean their effect on salmon and steelhead survival – it would be East Sand Island,” Roby advised.
Sallinger in 2016 called the East Sand Island cormorant massacre “One of the really significant failures in wildlife management in recent decades.”
“It was never about protecting salmon.”
Emphasized Sallinger later, “It was never about protecting salmon. This was always about scapegoating birds to avoid the real challenges that the U.S. Army Corps of Engineers needs to face up to. The result has been a stunning failure, whether you care about birds or fish.”
Offered Earthrise Law Center attorney Dan Rohlf, who fought the East Sand Island cormorant killing in court in 2015-2017, “It is long past time for the Corps and other federal agencies to step up and address the impacts that dams are having on federally listed salmon, including by removing the four federal dams on the lower Snake River.
“Federal judges have repeatedly ruled that federal agencies have not adequately addressed federal dams’ impacts on listed salmon,” Rohlf reminded.
Killing predators cannot compensate for global warming
Several studies indicate that global warming is also a major and growing factor.
Effects of elevated water temperature have been found to be contributing to the premature deaths of as many as half of the adult sockeye salmon returning to the Columbia River and tributaries to spawn.
The East Sand Island cormorant massacre was only one of many schemes pursued by state and federal agencies over the past several decades to try to recover salmon and steelhead by killing other species, also including gulls and California sea lions.
Sea lions as well as cormorants take the heat
For example, then-National Oceanic & Atmospheric Administration West Coast regional administrator Barry Thom, a September 2016 Trump administration appointee, on August 14, 2020 issued permits to kill 716 sea lions to the Oregon, Washington, and Idaho state agencies governing fisheries.
Additional permittees include the Confederated Tribes of the Umatilla Reservation, Confederated Tribes of the Warm Springs Reservation of Oregon, and the Confederated Tribes and Bands of the Yakama Nation.
Blaming sea lions intensifies
Killing California sea lions has predictably accomplished nothing, but blaming sea lions for salmon scarcity intensified in January 2023 when a report commissioned by the Washington state legislature and completed by the Washington Academy of the Sciences suggested, essentially, that more seals and sea lions should be killed, experimentally, to see if killing more might help when killing fewer did not.
Archaeological evidence suggests that harbor seals and California sea lions, though gradually recovering from the brink of extirpation from the U.S. Pacific Coast circa 1900, are probably still much less numerous than in pre-settlement times.
Other fish-eating marine mammals once common to the region, including orcas and Steller sea lions, have long been in decline. Elephant seals have reappeared, but in small numbers.