Florida Is Killing Invasive Iguanas by Smashing Their Skulls

The state of Florida is trying to figure out the best way to get rid of wild iguanas. So far, bashing in their heads appears to be the unfortunate method of choice.

What’s prompting this mass execution? Iguanas don’t belong in Florida. They’re considered an invasive species, and they do real damage to the locales in which they take up residence.

The Florida Fish and Wildlife Conservation Commission  recently hired University of Florida researchers to seek out, trap and/or kill as many iguanas as they can find. It’s part of a $63,000 research project to determine the best strategies for eliminating these reptiles.

green iguana on branch

Photo credit: Thinkstock

Through the end of May 2018, a 15-member University of Florida team will scour Broward County, searching for iguanas. When they find the creatures, wildlife scientists trap them so they can be safely euthanized. And if they can’t trap the iguanas, they kill them on the spot. So far, the team has killed at least 300.

“Most of what we’re doing is blunt force trauma,” Jenny Ketterlin, a UF wildlife biologist and research coordinator, told the Sun-Sentinel. “Hitting their head very hard against a solid object.”

A primary tool for the job is a captive bolt gun, similar to those used to kill animals in slaughterhouses. The other technique involves picking up the iguana and smashing its head  against a hard surface — often, the side of the team’s truck or boat.

Anyone can legally kill iguanas in Florida, since they’re an invasive species. However, euthanization must be humane, or it becomes animal cruelty – a criminal offense. In Florida, animal cruelty is a first-degree misdemeanor and punishable by one year in prison, a fine of $5,000 or both.

Invasive Species Cause Endless Trouble

Iguanas can’t be relocated. They don’t belong in the wild in the United States. Their true home is in the hot, tropical rainforest areas of Mexico, Central America, the Amazon and the Caribbean Islands.

Iguanas arrived in Florida’s Miami-Dade County as exotic pets around 1966. A typical specimen grows to over six feet long, with sharp teeth, impressive claws and tails like whips.

Inevitably, many escaped or were freed by their captors. Iguanas breed prolifically — they can lay 100 eggs up to three times every year. As their population increased, they made their way to the Florida Keys by 1995. They moved onward to Broward County in 2001 and Palm Beach by 2003. And iguanas have no natural predators in the U.S.

iguana on Florida palm tree

Photo credit: Thinkstock

Iguanas remain in warm southern Florida, as its most similar to their natural jungle habitat. They generally inhabit areas near man-made canals. A surprising south Florida winter temperature dip into the 30s in 2010 froze and killed a number of iguanas — but not nearly enough.

No one knows how many iguanas exist in Florida at present, but there are certainly a lot of them — enough to cause endless problems.

  • Iguanas eat local flora and fauna, from ornamental vegetation like hibiscus, orchids, impatiens, roses and garden greens, to fruits like figs, mangos, tomatoes and melons.
  • They poop on decks and in swimming pools, exposing people and companion animals to Salmonella bacteria.
  • They cause significant erosion problems by burrowing beside sidewalks, seawalls and building foundations.

How to Be Humane When Death is the Only Answer?

Because iguanas can’t be captured and re-homed, they have to be killed to stem the tide of overpopulation .

The question is — what’s really the most humane way to kill these creatures? Reasonable minds differ on this question. Some homeowners with an iguana problem take them out by shooting them with pellet guns. Others try poisoning, drowning or trapping and freezing them. Not all of these practices are legal, and some qualify as criminal animal cruelty under Florida law.

“Hitting the iguana on the head with a shovel is OK, as long as you aim correctly and kill it in the first stroke,” Zoo Miami’s Ron Magill told the Sun Sentinel. “Hit it more than once and you could be charged with a crime.”

pet iguana

Photo credit: Thinkstock

To accomplish on-the-spot death, experts recommend stabbing iguanas in the brain, decapitating them quickly and cleanly, or using the pellet gun method. The UF team chose the blunt force trauma method. Some veterinarians disagree, asserting that only euthanasia is a guaranteed kind method.

Since one must capture an iguana to humanely kill it, why isn’t Florida taking the kindest way out for these unfortunate reptiles? Come on, Sunshine State.

If we have to kill iguanas to eradicate their presence, can’t we do it in the most humane way possible? All this brain bashing just seems horrific and wrong.

Photo Credit: John Cobb/Unsplash


Sarah Hill
Sarah Hill8 days ago

If a species is not indigenous, they have no enemies. There is nothing to keep them in check, they then become pests.

Jamie Clemons
Jamie C13 days ago

Mark Donner They do harm the environment they damage natural areas, and consume things important to dwindling species. Like zombies you have to shoot or hit them in the head.

Jamie Clemons
Jamie C13 days ago

Crude but effective.

Chad A
Chad A18 days ago

Oh no.

Susan Fong
Susan Fong24 days ago

If they must kill the iguanas, USE A SEDATIVE FIRST TO CONTROL THE IGUANA FOLLOWED BY A FAST-ACTING, RELATIVELY PAINLESS LETHAL INJECTION. This bashing of the skulls of iguanas is savagery. This must be painful and terrifying for them. AS USUAL, PEOPLE caused this problem by introducing iguanas into the Florida ecosystem. WHY MUST ANIMALS ALWAYS PAY THE PRICE FOR THE STUPIDITY OF PEOPLE?!

Cynthia Howard
Cynthia Howard24 days ago

Since they have to capture to kill them it should be done quickly and humanely. Also pregnant iguanas need to be included too obviously. Horses and many other animals are afraid of iguanas, the wild one don't always have a sweet nature, they are a nuisance through no fault of their own.

Elisabeth H
Elisabeth H27 days ago

no good. saddening.

Misss D
Misss D28 days ago

Trump's wall will not protect against the legal importation of alien exotic fauna such as iguanas, which is how this problem started. What it will do, is stop the natural movement and migration of species that are native to America and Mexico and further destabilise America's ecosystems. The solution lies in tightening the laws and enforcement regarding importation of exotic animals as pets and not building a wall that will prevent American animals from crossing to Mexico and back as they have done for millions of years.

John B
John B29 days ago

Thanks Susan for sharing the disturbing info.

Mark Donner
Mark Donnerabout a month ago

Exactly why is Florida not "meant" to have iguanas when they do NO harm to the environment and in fact contribute to Florida's ecosystem (as opposed to the humans that have wrecked Florida)