OCALA, Fla. — University of Florida researchers said they counted about 200 rhesus macaque monkeys at Silver Springs State Park, which is part of the reason two areas of the park have been shut down.
Park rangers said the monkey population is growing and the animals have been showing more aggression around people.
[ Last week, a troop surrounded a family. ]
Dr. Steve Johnson, an associate professor from the University of Florida has been researching the non-native rhesus macaques for years.
He said the myth that the monkeys escaped during the filming of a Tarzan movie isn’t true.
[ Read: Wild monkeys attack Florida family ]
“Back in the '30s and '40s, there was a couple groups introduced by a tour boat operator, hoping to increase tourism,” said Johnson.
He said initially there were about a dozen, but the monkeys quickly reproduced and by the early '80s, there were about 400.
Watch: Troop surrounds family at Silver Springs State Park
At that time, the state allowed trapping, and more than 200 were sold for biomedical research.
[ Read: Visitors say it's time to relocate wild monkeys at Silver Springs State Park ]
In the late '80s the state sterilized about 20 females to control the population, and between 1998 and 2012, the state allowed a private trapper to catch some of the animals.
“We estimated that a year ago there were probably about 175 rhesus macaques within the grounds of Silver Springs State Park,” said Johnson.
He believes that number has likely grown to more than 200 by now.
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The park said it is working with the Florida Fish and Wildlife Conservation Commission on a plan for the monkeys.
“If these kinds of interactions continue to increase, the park may feel some pressure to try to do something, but that’s going to be up to them,” said Johnson.
Since the monkeys have been in the park, there have been 18 confirmed reports of the animals biting or scratching people.
Researchers said many of the monkeys have the herpes B virus.
Researched also set up an experiment to see if the monkeys are harmful to the native Florida environment.
They put out fake bird nests with fake eggs in them, and said the monkeys took the eggs.
Researchers said that means the animals may be invasive.