A UF Laser's Latest Application: Mapping Endangered Bird Habitat

August 31, 1999

GAINESVILLE — With a population of around 3,000 living only in the Florida Everglades, the Cape Sable seaside sparrow is one of the nation’s most endangered birds.

But help may soon be on the way from two University of Florida engineering professors who plan to create a detailed map of part of the sparrow’s habitat using a cutting-edge airborne laser mapping system. The project, which likely will begin this winter, is the most recent of more than a half-dozen diverse mapping projects led by the engineers since they first used the system to map hurricane-damaged beaches in 1996.

“This year, we’ve used the system to map everything from a county landfill to natural areas on Cape Canaveral to flood zones in Pinellas County,” said Ramesh Shrestha, a UF professor of civil engineering. “So far, it’s proved accurate and very, very fast.”

The U.S. Geological Survey has asked Shrestha and Bill Carter, a UF adjunct professor of civil engineering, to map the elevation of the ground in a 25-square-mile area of the Cape Sable sparrow’s Everglades home. The elevation, accurate to 1 foot, should reveal the ideal habitat for the sparrow, whose nests are easily swamped by floods or scavenged by predators if not built among marsh grasses at the right height.

“The idea is to protect the best nesting areas from people going in with airboats or other disturbances,” Carter said. “But first they have to know what the best areas are.”

While it would be extremely time consuming and difficult to map the elevations of 25 acres of marsh grass through traditional surveying techniques, Shrestha said he and Carter likely will be able to complete the job in a week or two using the laser system.

Aloft in a small plane, the system has a highly accurate pulse laser that emits 10,000 pulses of light each second toward the ground. The pulses hit and scatter back, allowing the system to gauge the distance between the plane and ground. The result is a digital image of the ground that mimics each small variation in elevation with corresponding data for the latitude, longitude and height of thousands of points on the ground.

While the sparrow project represents the first use of the laser system for animal conservation, it has been used for several other conservation-related projects this year.

For example, the engineers used the system to map the marsh around Cedar Key to help federal officials determine if it is in poor health because of a decline in the flow of fresh water from the Suwannee River. They also have mapped the treetop altitude and ground elevation at Cape Canaveral to generate data expected to help Kennedy Space Center officials determine the area’s susceptibility to fire, among other information.

“They’d like to know, if they get a fire, how big an area is likely to be burned and whether it will impinge on any of their launch activities,” Carter said.

The University of Florida purchased the $1.3 million laser mapping system four months ago after Carter and Shrestha modified it and used it on a trial basis for some time. The bulk of the money came from the proceeds of the engineers’ biggest project to date: mapping Pinellas County to determine what areas are most prone to flooding. Carter and Shrestha’s findings in some cases conflict with Federal Emergency Management Agency flood maps of the county and have resulted in a delay of planned increases in flood insurance rates for many of the county’s residents, they said.