February 2006 Issues Online June 2007 April 2007 February 2007 December 2006 October 2006 August 2006 June 2006 April 2006 February 2006 December 2005 October 2005 August 2005 June 2005 April 2005 February 2005 December 2004 October 2004 August 2004 June 2004 April 2004 February 2004 December 2003 October 2003 August 2003 June 2003 April 2003 February 2003 December 2002 October 2002 August 2002 June 2002 April 2002 February 2002 December 2001 October 2001 August 2001 June 2001 April 2001 February 2001 December 2000 October 2000 August 2000 June 2000 April 2000 February 2000 December 1999 October 1999 August 1999 June 1999 April 1999 February 1999 December 1998 October 1998 August 1998 June 1998 April 1998 February 1998 December 1997 October 1997 August 1997 June 1997 April 1997 February 1997 December 1996 October 1996 August 1996 June 1996 April 1996 February 1996 December 1995 October 1995 August 1995 June 1995 April 1995 February 1995 December 1994 October 1994 August 1994 June 1994 April 1994 February 1994 December 1993 October 1993 August 1993 Select any issue from the menu in this bar.

Luring Terns

How do you convince thousands of seabirds that they're in the wrong place? That's the task confronting Nanette Seto, the Portland-based biologist who runs Fish & Wildlife's Caspian tern management program.

Caspians, North America's largest tern, once nested in interior wetlands like the Klamath Basin marshes. With these habitats lost, they shifted coastward. By 1991, most of the western population of Caspian terns had regrouped on Rice Island near the mouth of the Columbia River, where they took a heavy toll on hatchery-bred salmon and steelhead smolts heading out to sea. The birds were encouraged to relocate to East Sand Island, closer to the ocean, and salmonids dropped to 17% of their diet by 2004. But that's still 3.5 million fish, more than NOAA Fisheries considers acceptable. So most of the terns will be moving again: by reducing nesting habitat, wildlife managers intend to force 13,000 of the 18,000 Caspians to breed elsewhere.

Plans call for the Army Corps of Engineers to create or enhance alternative breeding habitat in Washington, Oregon, and Northern California. In the Bay Area, target sites are Brooks Island, where encroaching vegetation will be cleared, Hayward Regional Shoreline, which already has suitable dredge-spoil islands, and the Don Edwards S.F. Bay National Wildlife Refuge, where a new island may be constructed in one of the salt ponds. Caspians are no strangers to the area-S.F. Bay used to house large colonies of the birds at Bair Island and Alameda; now there are about 1,000 pairs already nesting at Brooks Island and 50 at the Refuge.

Fish & Wildlife will use decoys and recorded calls to attract terns to the new sites. Seto hopes Caspians that winter in Mexico and Southern California will stop to nest in S.F. Bay rather than continuing on to the Columbia. The impact on other Bay waterbirds is expected to be minimal; the big Caspian terns and the smaller, endangered least terns feed on fish of different sizes.

A final environmental impact statement on the project awaits interagency consultation. Funding is problematic: The $400,000 price tag for the Bay component could be higher if erosion at Brooks Island is addressed, and post-hurricane reconstruction in the Gulf of Mexico has stretched the Army Corps' budget.

«To February 2006 Index

[ ABAG HOME | SFEP HOME ]

Copyright © 2002, San Francisco Estuary Project