HOOK AND FUR By Bob Brown Double-crested cormorants are a predominate predator of juvenile fish and the major predator of protected juvenile salmon in the Columbia River. It is estimated the birds consume roughly 12 million juvenile salmon and steelhead annually, many of which are listed as endangered or threatened under the federal Endangered Species Act. To curtail the predation, the U.S. Corps of Engineers requested and received a one-year depredation permit from the U.S. Fish and Wildlife Service to cull 3,489 double-crested cormorants and oil and destroy 5,879 of their nests, plus 105 Brandt's cormorants and 10 pelagic cormorants through January 31, 2016. A U.S Army Corps of Engineers contractor, Wildlife Services, began the culling activity last May on East Sand Island in the Columbia River estuary. The island is a major nesting site for breeding cormorants estimated to between 5.380 and 5,939 pairs. According to the Corps, the colony of cormorants on the island increased from about 100 breeding pairs in 1989 to more than 15,000 pairs in 2013. As the populations of cormorants grew, along with populations of gulls and Caspian terns, so did the number of juvenile salmon and steelhead eaten as they migrated down the Columbia River. The Corps plans to cut the size of the breeding colony on East Sand Island- believed to be the largest in the world- to between 5,380 and 5,939 breeding pairs. The colony accounts for 98 percent of the double-crested cormorant breeding population in the estuary. Through Sept. 3, Wildlife Services had killed only 158 birds and oiled 5,089 nests. Both numbers remained unchanged since July 9 as activity came to a halt when nesting activity on the island was in full swing. However, culling activity picked up during the week of Sept. 17, and as of Oct. 1, the count had risen to 1.707 birds culled. Oiling of nests on East Sand Island remained at 5,089 nests as all the Corps cormorant management activity moved away from the island. The Columbia Basin Bulletin reported more double-crested cormorants of have been killed during the last three weeks than during the entire summer of culling activity. Some 486 double-crested cormorants were killed in the most recent week, along with one Brandt's cormorant. During the week ending Sept. 24, 358 double-crested cormorants and five Brandt's were killed. During the previous week (ending Sept. 17), 505 were killed and for the week ending September 10, 200 cormorants were killed. Bob Winters, project manager of the Corps' cormorant management plan, said Wildlife Services changed to boat-based shooting when nesting activity ceased on the island and many of the birds begun to disperse. The culling activity will cease when most of the birds have dispersed by mid-to- late October. Right now, Wildlife Services are targeting adults and only double-crested cormorants. The Audubon Society of Portland, along with four other conservation and animal welfare groups, filed a lawsuit in late April to stop the Corps from initiating its cormorant management plan; however, a motion for a preliminary injunction to stop the plan immediately was denied May 8 which allowed the Corps to move ahead with its culling plan this year. The lawsuit will continue as both sides have agreed on a course of action that results in final oral arguments in federal court March 7, 2016,
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