ISLAND REPORTER (Sanibel, Florida) 03 July 08 City receives necropsy results for Nile Monitor (Ida Vaynberg)
The necropsy results are in for the partially decomposed body of the six- foot Nile Monitor Lizard that had been discovered floating in an inland lake just west of Rabbit Road. However, there is not enough evidence to determine the cause of death.
Chris Lechowicz, a herpetologist with the Sanibel-Captiva Conservation Foundation (SCCF), performed the necropsy on the reptile. He said the lizard weighed 14.8 pounds and was a sexually mature male.
Lechowicz explained that it was difficult to determine what caused the reptile to die considering that it did not bear any wounds on its body from an attack by another predator and that it also looked clean internally.
“An animal that size should have had a full gut. So it must have been sick for a little while,” he said, adding that an animal that size should have had more than what they found in its stomach. “We’re just guessing, we don’t know why.”
Upon examination, its stomach contents included an eggshell that Lechowicz identified as a freshwater turtle egg and two clumps of leaves that the reptile may have ingested while attacking some type of prey in a tree or a bush. The reptiles are considered to be carnivores and are not known to consume plant material.
He also said that based on the decomposition of the body during the necropsy, it had minor bloating and had only been dead for a short time, perhaps a little more than a day.
The remains have been re-frozen and are expected to be shipped to Florida Gulf Coast University to be stored in their freezer. They eventually will be transported to the University of Tampa, where Dr. Todd Cambell will perform an additional inspection of the body.
Lechowicz, who has been with SCCF for six years, also said that one of the reasons for further inspection is to determine the age of the reptile.
Christen Steel, a Snowy Plover technician at SCCF, was one of the people present at the necropsy. She said that it was exciting to watch and help Lechowicz during the process.
“It was pretty amazing,” she said. “The smell was pretty horrible, but once you got past that, the stuff that we found inside it was interesting. We were all just pretty amazed and perplexed by the find and a lot of people came to see the dissection.”
The body was discovered by an island resident, Barbara Bolt, on June 14. Bolt contacted the Sanibel Police Department after discovering the reptile, initially believing it to be an alligator.
Officer Kerry Griner identified the animal as a Nile Monitor lizard and contacted the City’s Exotic Lizard Control contractor Chris Harlow, who confirmed Griner’s assessment.
This was the third confirmed Nile Monitor sighting on Sanibel, providing additional proof that there is an established population of these lizards on the island.
In 2007, another Nile Monitor was “caught” on police video footage as an officer passed what appeared to be an injured animal on Periwinkle Way.
After reviewing the footage, the City’s Natural Resources Department confirmed that it was a Nile Monitor, which they believe survived after being struck by a motor vehicle near Roadside City Park.
In 2006, a resident took pictures of one of these lizards swimming in a pond near Clam Bayou.
The City began its Exotic Lizard Management Program last year to help manage the Green Iguana (Iguana Iguana) and the Nile Monitor lizard (Varanus Niloticus) populations.
Both of these species are considered to be exotic species not native to the island and pose a threat to its native plant and animal species.
As of July 1, the City has removed a total of 521 iguanas this year, and a total of 312 in 2007.
Nile Monitors are native to Africa and can reach up to seven feet in length.
They are excellent swimmers that tend to live near vegetated canal banks and can evade being captured by diving into adjacent bodies of water.
One of the problems associated with this predator is that it has a high reproductive rate and may lay as many as 84 eggs in a single clutch, with an average of 60 eggs laid. They have no natural predators on the island and can pose a major threat to its birds and gopher tortoises because of their fondness for eggs and ability to climb well to reach bird nests and rookeries.
While they may look similar to the iguana, they can be distinguished by their elongated head and lack spiny crest and dorsal spines.
The citizens of Sanibel are being asked to assist the City in eliminating these unwanted predators. If you see what appears to be a Nile Monitor Lizard, try to keep it in your sight and call the Sanibel Police Department at 472-3111.
City receives necropsy results for Nile Monitor