Double-crested Cormorant Management Plan to Reduce Predation of Juvenile Salmonids in the Columbia River Estuary

The Western Population- East Sand Island, Lower Columbia River, Oregon

Since 1990, the growth of the double-crested cormorant western population has been primarily associated with the growth of the East Sand Island colony.  The nesting colony of double-crested cormorants on East Sand Island has increased nearly 100-fold since the colony was first recorded in 1989.  The colony at East Sand Island has remained relatively stable since 2004, averaging approximately 12,900 breeding pairs.  The largest breeding colony of double-crested cormorants in western North America, and likely all of North America, resides on East Sand Island.

Double-crested Cormorant Management Plan to Reduce Predation of Juvenile Salmonids in the Columbia River Estuary

In 2015, the U.S. Army Corps of Engineers (Corps) prepared a Final Environmental Impact Statement (FEIS) and management plan to reduce predation of juvenile salmon and steelhead by double-crested cormorants in the Columbia River Estuary.  The Corps chose to implement Alternative C-1, documented in their Record of Decision.  For more information please visit
http://www.nwp.usace.army.mil/environment/cormorants/

The U.S. Fish and Wildlife Service was a cooperating agency on the FEIS, providing technical expertise on Double-crested Cormorant monitoring and population model.  The U.S. Fish and Wildlife Service developed the population model to provide a science-based assessment of the effects of different levels of individual and egg take on the East Sand Island colony and the western population of double-crested cormorants.

The U.S. Fish and Wildlife Service received an application for a Federal Migratory Bird Permit from the Corps after they signed their Record of Decision, for the take of adult cormorants and nests, so that they may implement Alternative C-1 in the FEIS.  We used the analyses in the FEIS to support our permit decision-making on this application, documented in our Record of Decision.

U.S. Fish and Wildlife Service Record of Decision

The U.S. Fish and Wildlife Service issued a depredation permit valid in 2015 that allowed the Corps of Engineers to implement the first of year of Double-crested Cormorant management on East Sand Island as applied for and described in Alternative C-1 of their FEIS; this decision is described in the U.S. Fish and Wildlife Service’s Record of Decision.  The permit authorized the take of 3,489 individual Double-crested Cormorants and 5,879 nests, and 105 Brandt’s and 10 Pelagic cormorants.