Laura Erickson's For the Birds

Dusky Seaside Sparrow

(Recording of a Seaside Sparrow)

On June 16, 1989, Florida conservationists declared the Dusky Seaside Sparrow to be extinct, marking the first time any North American bird has been lost since the Endangered Species Act was first passed in 1966.

Attempts to preserve this unique little sparrow were doomed to failure from the start. The Dusky Seaside Sparrow required an open, brush-free salt marsh at an elevation of exactly 10-15 feet above sea level. Historically it has only been recorded in the vicinity of Merritt Island and Titusville in Florida. Merritt Island, which borders Cape Canaveral, has been preserved from development as a National Wildlife Refuge, ironically not so much to save the sparrow but in order to protect the Kennedy Space Center’s sensitive operations.

The U.S. Fish and Wildlife Service did spend 5 million dollars to purchase the St. John’s River National Wildlife Refuge to preserve portions of the Dusky Seaside Sparrow’s habitat, but was helpless to stop the drainage and fires originating outside its borders. Flushing its salt water marshes with fresh water in mosquito abatement projects destroyed salt water grasses, disrupting the sensitive habitat.

The loss of this little bird was rapid and inexorable. The book Birds of Florida, published in 1945, calls the species abundant within its range. There were at least 4,000 individuals counted in censuses in the 1950’s. The species account in the National Geographic Society’s book Song and Garden Birds, published in 1964, doesn’t mention its dwindling population, which wasn’t yet apparent, but by 1968 only 400 were censused—a mere 10% of the previous decade’s total. In 1977 and 1978, 24 birds were found on censuses, and all were males. The following year, 1979, only 13 males remained, and only 6 were found by 1980.

Five of these were captured for captive breeding, and an intense search for a female began. None were found, but wildlife managers decided to at least try to preserve the genetic line by an unsuccessful attempt to hybridize these males with females of the closely related Scott’s Seaside Sparrow. This experiment took place at Walt Disney World’s Discovery Island. I suspect that excessive meddling by removing eggs to maximize production was at least partly to blame for the project’s failure—one poor Scott’s female produced 8 clutches of 20 eggs, but only 5 hatched and only one chick survived. All in all, the five captive males produced only 5 hybrids. Of them, one died of natural causes, and a storm ripped open the cages of the others, killing one and releasing the others a hundred miles from their natural habitat. Wildlife officials believe they were killed by rats or other predators.

Meanwhile the last known Dusky Seaside Sparrow died at Disney World on June 16, 1987. You can see its stuffed body on display at Discovery Island, if you’re willing to pay the entrance fees. It’s ironic that this bird who was brought to extinction by development is displayed for profit by one of Florida’s biggest polluters and developers.

(Recording of a Seaside Sparrow)

This is Laura Erickson, and this program has been “For the Birds.”