ALTAMONTE SPRINGS, Florida – Populations of threatened Florida scrub-jays are declining, according to the latest annual Nature Conservancy study of jay populations across Central Florida. The scrub-jay is the only bird found only in Florida, but these small, light blue birds are disappearing at 40 percent of their population sites, volunteer jay counters observed.
Results of a sixth-annual summer survey of Florida scrub-jays along the Lake Wales Ridge were reported recently at a volunteer recognition event at Historic Bok Sanctuary.
Statewide, virtually all of the large populations still occur only on the Lake Wales Ridge, Ocala National Forest, and on Kennedy Space Center or Cape Canaveral Air Station.
The Jay Watch results were gathered from 41 sites in 11 counties by 165 volunteers donating 1,624 hours of service.
Among the 15 Jay Watch sites first surveyed in 2002-2004, populations have declined at 40 percent of sites, stayed the same at 40 percent and increased at 20 percent, the volunteers noted.
Two-thirds of populations declined at 26 other Jay Watch sites, some of which were also covered during the 1992-93 statewide survey.
Florida scrub-jays – friendly birds that mate for life and live in multigenerational families in very specific habitat – will abandon an oak scrub habitat if it is not properly managed, such as when the trees grow too large due to lack of fire, the study shows.
The data includes information on habitat and vegetation which has been shared with site managers to better inform their critical management decisions.
“Management actions informed by the results are a positive outcome of the survey,” said Cheryl Millett, the Conservancy’s biologist who coordinates Jay Watch.
“Unfortunately, seeing the results of management can take time. It can be five years before burned areas are suitable for scrub-jays,” she said. “In the meantime, the dedication of our volunteers is inspiring.”
In the 2007 Nature Conservancy Jay Watch annual report, Reed Bowman, Ph.D., associate research biologist at the Archbold Biological Station says, “Although jay populations fared relatively well during 2006, at many sites 2007 was a bust. At Archbold Biological Station during 2006, over 100 juveniles survived to July. During that same period in 2007, only 18 survived. This pattern was repeated at many sites on the Lake Wales Ridge; juvenile production was much lower in 2007.”
While the scrub-jay is Florida’s only endemic bird, Florida’s official state bird is the mockingbird. Attempts to have that status assigned to the Florida scrub-jay have not yet been successful.
The U.S. Fish and Wildlife Service North Florida Field Office says the major cause of the decline of the Florida scrub-jay has been habitat destruction by humans that probably began in the mid-1800s when scrub was cleared for towns, citrus groves, and pastures.
The destruction of scrub accelerated throughout the 1900s, especially after 1950, for the development of air fields, phosphate mines, pine plantations, military installations, super highways, mobile home parks, shopping malls, rocket-launch complexes, tourist resorts, golf courses, and theme parks.
Fire suppression accompanying human settlement further reduced usable habitat throughout the species’ original range
Still, said Bowman, “we have reason to hope.”
“New populations are being established through vigorous management efforts,” he said. Habitats are being restored, and jays are being translocated to build large, healthy populations that have the potential to rescue populations that were on the verge of extinction. We need as many voices as possible to heighten awareness of the plight of our scrub species. The volunteers of Jay Watch are the loudest singers.”
To read the Conservancy’s Florida Scrub-Jay report click here.
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