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The Shadowy Rail
The strong arm of wetland restoration has flushed a small, secretive rail from the North Bay salt marshes, and it isn't the clapper kind. The last few thousand California black rails live in the last relatively pristine and mature marshes of the North Bay, flanked by more degraded turf that is the focus of dozens of well-intended restoration projects. "These projects are more than a golden opportunity for the rails," says the San Pablo Bay Wildlife Refuge's Betsy Radtke, "Restoring this habitat is essential for their survival."
The black rail has often been overlooked when it comes to conservation because it simply less obvious-and maybe less "charismatic"-than certain other endangered species, according to Jules Evens of Point Reyes Bird Observatory. The clapper rail is "larger and louder" and easier to detect than the black rail.
But there are other reasons for the black rail's obscurity. It prefers well-vegetated upper marsh over the lower marsh used by many species, which "is good news in a way because the rail is so furtive and difficult to detect that its been overlooked in some spots, which may have actually helped it," says Evens. "But the highest reaches of the marsh are also usually the first places to be developed-where the filling and levee-building takes place. So the impact has been greatest there. Of the bay wetlands, this upper fringing habitat has suffered the greatest loss." Evens predicts that if and when the black rail is finally federally listed (it is currently a state "threatened" species), and its habitat protected, enormous public outcry will be heard from those who will equate preserving rail habitat with lost economic opportunities.
But economics and politics aren't the only enemies of the tiny, oddly-shaped bird ("think of a heavy-bottomed robin or towhee without the tail" says Evens). In extreme high tides, the rail is forced to the upper limits of the marsh where, especially in degraded, poorly vegetated marshes, it becomes easy prey for hawks, egrets, and herons (not to mention numerous non-native predators like feral cats and Norway rats). If forced to, the rail will fly-but not well. "I've seen egrets swoop right down and catch them mid-flight," says Evens. "There is no way the rails can outfly them."
While Evens is happy to see the black rail be noticed at last, he is concerned that restoration efforts take into account the rail's sensitivity to changes in its habitat, particularly alterations to freshwater inflows. "The rails rely on a whole suite of factors," he says. "If you change any one of them, you can alter the whole population within an area." Evens explains that because elevations above the mean high water line tend to be a little less saline, they support a food web of terrestrial organisms which the rails rely on. "It's difficult to keep the elevations correct," says Evens. "If you're creating more sites overall, its got to be good, but to ensure that black rails are going to colonize a site, you'd almost have to micro-manage it."
Contact: Jules Evens (415) 663-1148
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