The Hunt For Black Rail

by Mike Stiles

The Black Rail has been called the most elusive bird in the United States. This sparrow-sized bird of fresh and salt water marshes is very secretive, and prefers to run instead of flying to escape its enemies. It is very vocal though, and many birders have added the Black Rail to their life lists with nighttime forays to Morro Bay, sometimes playing a tape, and listening for their loud KEEK-EEE-DOO call in response. At least birders used to be able to visit Morro Bay for Black Rail. It seems they are now gone.

Black Rail was first discovered in California in 1859, and by the 1940's they were found from Marin County to San Diego, usually associated with salt marshes around coastal bays. Of course, with the state's meteoric population growth came the dredging, draining, and filling of many of these coastal estuaries for boat harbors and housing developments. By the 1970's, a study postulated that, save for the relatively healthy population in the San Francisco Bay, the rest of the state's Black Rails only numbered in the several hundreds.

The rail's preference for shallow marine bays and marshes subject to tidal changes makes it a dangerous environment for them. They are especially vulnerable when pushed to the edges of the marsh at high tide and are easily preyed upon by herons, egrets, owls, and hawks. In one study at Tomales Bay, during 15 hours of observations at high tides, 17 Black Rails were eaten by Great Egrets and Great Blue Herons. It is thought that raccoons and coyotes also prey on the rails around Morro Bay.

The records for Black Rail sightings in Morro Bay start in the early 1960's and two birds from that time period now reside in museum drawers. Morro Bay Christmas Bird Counts between 1981 and 2003 recorded Black Rail in every year except one, but between 2004 and 2010, the bird was recorded just once in those seven years.

Three studies that were done on Morro Bay—in 1971, 1987, and 2001. All turned up small populations of Black Rail. Most of the birds in the two earlier studies were found along South Bay Boulevard and along the Los Osos Creek from Turri Road. The 2001 study found only four birds, all near the edge of the Elfin Forest.

With a grant from the Morro Bay National Estuary Program and Audubon California, and with assistance from the Morro Coast Audubon Society, John Roser and Andrea Jones headed a team of observers in the Fall of 2009 and Spring of 2010 for the most extensive field research ever of Black Rail on Morro Bay. As in the other studies, tapes were played to elicit responses from the rails. Ninety-five points along the bay were each given a seven minute period of playing tapes and listening for responses. These points were repeated a total of three times in both the fall and spring attempts.

After that well organized attempt, no Black Rails could be confirmed on Morro Bay. John Roser and I gave it another try at two of the historic locations this past spring, but no rails responded to the tapes. It seems they are indeed gone, extirpated from our area.

Some humans don't care whether or not some mouse-sized bird can be found on Morro Bay. To me, it's the canary in the coal mine. For whatever reason—global warming, more egrets, or even people feeding raccoons—something is happening on our bay to drive the Black Rail away.

Most of the information in this article came from John Roser's detailed unpublished report, "An Assessment of the Current (2009-2010) and Historic Status of the California Black Rail at Morro Bay, California."

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