Pesticides suspected in Florida gator decline
March 15, 1998
Deep in the Florida Everglades, biologists are finding
some alligators hundreds of pounds underweight
Web posted at: 1:12 p.m. EST (1812 GMT)
MIAMI (CNN) -- Researchers in Florida are worried pollutants
may be affecting the reproductive systems of alligators, and
that if chemicals are responsible for low alligator births,
humans could be at risk too.
In 1980, at Lake Apopka near Orlando, Florida, researchers found a correlation between reproductive troubles in
alligators and large amounts of pesticides, containing DDT and DDE, that had spilled into the lake.
Reproductive organs were stunted, and testosterone levels
were not normal.
"We started to realize that there were large concentrations
in the eggs, that the females had accumulated these
contaminants," Louis Guillette, a zoologist at the University
of Florida, told CNN. ( 119K/10 sec. AIFF or WAV sound)
Zoologist Guillette analyzes alligator weight and
reproduction from the finds
Scientists thought the problem may be local, since Apopka was
considered an ecological disaster.
Trouble in paradise
But now, researchers have evidence to suggest reproductive
troubles may plague alligator habitats throughout the state. What they can't find is a clear cause, like the Apopka chemical spill.
Researchers studied juvenile alligators from Lake Okeechobee,
Florida's largest lake. Growth and reproductive hormone
levels were severely stunted in 100 juveniles.
In the Everglades, biologists from the University of Miami,
are finding alligators maxing out at 200 pounds or less,
often hundreds of pounds lighter than alligators in other
parts of the state.
In addition, the Everglades alligators are taking 20 years to
reach reproductive size, the Miami researchers said.
Researches say pollution is a likely suspect
"There are a multitude of hypotheses," Guillette said.
Among them: changes in diet, changes in nest temperatures,
or exposures to pesticides.
But the most likely culprit, researchers say, is pesticides.
Pesticides, fertilizers and phosphorus runoff may be draining
into the alligator habitats from nearby agricultural areas.
Researchers say whatever is altering the alligators may
affect humans as well.
Because of their place at the top of the food chain, the
health of the alligator may be making a strong statement
about the health of the environment.
Miami Bureau Chief John Zarrella contributed to this report.