Photographed by Bette Jackson



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Hi, I'm Dr. Jerry Jackson, out with the wild things. As Florida's beaches have become increasingly used by humans, least terns must look elsewhere for nest sites. One habitat used by nesting least terns across the state is flat graveled rooftops. Pea gravel on some rooftops provides a habitat much like an open beach. On rooftops, terns have little disturbance from humans and predators. They've been successful enough that the birds return year after year. Rooftop nesting does have its own set of problems. Under the gravel, there's usually a layer of tar and in the heat of the summer, the tar gets sticky and gives off toxic fumes. The best roofs for tern nesting have a wall around the edge that prevents chicks from falling off and provides a bit of shade. Air-conditioning units on rooftops produce puddles in which both chicks and adults drink and bathe, but because of the wall, the surface is not cooled by breezes and temperatures can exceed 140 degrees. Adults have to work to keep eggs cool rather than to keep them warm. They soak breast feathers in water, then return to drip onto the nest. Tern chicks on rooftops often have badly burned feet; this tar beach is no substitute for the real thing.