Tuesday, May 17, 2005

A Reptile Dysfunction

The ISW is pleased to present this interesting piece about Florida's green iguana (Iguana iguana) invasion. It was written by Angela Comparato, a University of Florida student and up-and-coming journalist, who has graciously given permission for me to post it in its entirety. Thanks Angela!

photo of pet green iguana

GAINESVILLE, Fla. – Neon green baby iguanas, believed by pet owners to be sweet and small, may soon grow into aggressive, mature adults, whipping about their 3-foot-long tails and hissing whenever handled.

Ownership of the iguana has proven to be a bigger responsibility than expected, and as a result, many owners have released their pet iguanas of different species into the wild causing an ever-growing overpopulation and inundation of unwanted iguanas in South Florida.

Many people may not realize the ramifications, but a certain Gainesville reptile shop does.

“I hate the iguana trade, and that’s why I won’t participate in it,” said Nicol Spann, owner of 21st Century Reptiles.

Like many other pet shops that have voluntarily taken iguanas off the market, this reptile shop stopped selling iguanas four years ago. However, flea markets continue to sell them for about $10 each, Spann said.

The most common is the green iguana because they are often bought as pets. Iguanas appear to be an affordable and manageable pet because they can be kept in an inexpensive tank and only need to be fed once a week.

However, people eventually get rid of their iguana because they can bite, scratch, and whip their tails.

“Too many people buy iguanas and don’t realize that 99 percent of the time they become aggressive,” Spann said.

In addition, 21st Century Reptiles refuses to take in iguanas, receiving about one iguana owner a month trying to unload their unwanted pet to the store. One iguana was left at their doorstep, which they were forced to keep, Spann said.

Instead of accepting them, Spann suggests posting an adoption flyer on the store’s poster board.

The reptile shop would like to help these iguanas, but they can carry harmful parasites.

“Parasites can spread to the entire population of the reptiles in the store before I even know it’s there,” Spann said.

While parasites can cause problems, the biggest concern with iguanas is salmonella, a bacteria found in the intestines that can cause food poisoning, said William Kern, assistant professor of entomology and nematology at the University of Florida IFAS Fort Lauderdale Research and Education Center.

Any environment containing iguana feces has potential for infectious bacteria, Kern said.

The iguana trade can also be destructive to the environment.

“This is true not only in Florida but also in the home countries where they are taken from,” Spann said. “Removing them from the ecosystem allows certain plants to grow rampant.”

As a result, the biological balance is being thrown off in Mexico, Central America and South America where the iguanas originate.

Kern said there has been no survey conducted to estimate the number of iguanas in Florida, but the already large number is increasing.

These exotic pets are able to thrive because Florida has a subtropical climate.

Iguanas inhabit Monroe, Miami-Dade, Palm Beach, Collier, Lee, Sarasota and Pinellas Counties and are spreading to more coastal, central Florida counties, Kern said.

The overpopulation of the iguanas is wreaking havoc on the environment among the plants they feed on, including hibiscus, which is their favorite food.

“They will completely strip an entire tree,” Kern said. In addition, iguanas will eat valuable ornamental plants.

“If you’ve been babying an orchid, waiting for it to bloom, and then you come in, and it’s gone, you would get pretty mad,” Kern said.

Iguanas are also a threat to plants that are in danger of extinction.

The black spiny-tailed iguana feeds on the endangered curacao bush, said Kenneth Krysko, herpetologist at the Florida Museum of Natural History at the University of Florida.

Krysko said no one, including the state, is doing anything to control this problem.

“I find it funny that the state will fund millions of dollars if a small fruit fly is found in an orchid, yet when there is document of a reptile feeding on an endangered plant species, they don’t do anything,” Krysko said.

The iguanas could be controlled. However, the law protects the green iguana because it is listed by the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), which ensures that international trade of wild animals and plants does not threaten their survival.

Green iguanas are listed by CITES because of their importance to the pet trade.

Another obstacle in controlling the iguana overpopulation is public resistance of animal conservation groups that have a moral objection to the killing of these animals even though they are acting as pests, Kern said.

However, many botanical gardens are under financial pressure to control the iguanas because they are doing substantial damage to their plants.

“Do we risk the loss of potential clients by killing the iguanas, or on the other hand, do we risk the destruction of valuable plant collections if the iguanas are not controlled?” Kern said.


Anonymous said...

What a fantastic article, very informative and well written!

Anonymous said...

Bloody right. Leave the iguana wrestling to the experts!

Jennifer Forman Orth said...


Anonymous said...

i'm tired of planting flowers so that the iguanas have a free buffet all winter long. i say cull the stupid animals, they are a menace to our backyards. i have a family of six, including 3 cuban equanas that are nasty

Anonymous said...

Maybe what the gov't should do is live-trap the iguanas, treat them for parasites, and send them back to central America where they belong.

I had a lovely female iguana that died this April from gangrene. She was a very calm pet that loved being handled. She loved being petted by everyone. As a former iguana owner, I am loathe to even consider killing these beautiful animals. As a gardener, I can't let these critters destroy native habitat.

My solution is not that hard to implement. If the gov't can organize an iguana hunt, then its not too much work to capture them alive and send them to a way station prior to release in their native habitat.

Keys Treasures said...

Soon we may have to change the name of Big Pine Key to Big Iguana Key. ;-)

Despite all the stories, they are eating very little rare native plants. Hibuscus aren't native.

There are several green iguanas that spend time in my yard and I have never has any plant stripped.

All in all not a high priority invasive IMHO

Jennifer Forman Orth said...

Interesting observation keys, I wonder if anyone is studying what they are eating. Of course homeowners are likely to be just as (or even more) unhappy about hibiscus getting eaten as opposed to the native plant species.

Anonymous said...

Actually, let's get the facts straight here:

Iguanas are considered exotic unprotected wildlife. Iguanas are not native to Florida and so are not protected in Florida, except by anticruelty laws. In Florida, all captured iguanas must be kept in captivity as pets or captive breeding stock, or must be destroyed.

They may be caught by hand, noose pole, net, or traps. Only live traps and snares are legal in the State of Florida.

But, you know...when one's charging straight at you, I find that a pellet gun makes an efefctive deterrent.

Anonymous said...

I have never seen a charging iguana before. But when I can get close enough, I too find that my pellet gun is an effective means of pest control.

Anonymous said...

Killing all those iguanas is gonna be pretty hard. How many people need to be employed in these and forhow long. This would a fortune to impliment. But i'm all for killing them. They are edible too.

Anonymous said...

Do me a favor and kill a few of the two legged illeagles while your at it, there is far more of them running around then the four legged green ones and the two legged ones are eating the entire nation out of house and home.

Jennifer Forman Orth said...

Let's just leave those poor, sick birds out of it!

Anonymous said...

You can add Charlotte County Florida to your list of counties. We saw our first one ever about a year ago on the roof where we have lived for 25 years.

This week something was getting into our garage and biting holes in the bottom of "Mountain Dew" plastic bottles. At first we were baffled till we flipped the light on and caught the vandalism in progress... a big Iguana!

Sounds funny but he/she also left lots of calling cards (droppings) all over the shelves, it was a mess to clean up.

Englewood, Florida

Anonymous said...

We have an invasion of iguanas in our backyard, eating our plants, berries, etc, coming on our pool deck even when we're around. They are definitely a nuisance and we wish that there was a way to get rid of them. Our neighbors are complaining also.

Anonymous said...

iguanatrapper.com will trap and wuthenize your iguana pests in Broward and Palm beach County.

These iguanas have cost over $5000.00 worth of annuals and bedding plants on my maintenance properties in West Broward County.

They need to be eradicated with the Bufo Toad.

Anonymous said...

http://www.iguanacontrol.com is trapping iguanas in Broward County.

Anonymous said...

Any sightings of iguanas in Pinellas County?

Anonymous said...

maybe you should do more research about iguana's before you post anything about them... pet iguanas don't become aggressive 99% time...talk to iguana owners who are experienced..and you'll know...yes many become aggressive but not 99% this is stupid!

Anonymous said...

Saw a 3 ft Iguana on a channel marker off Fort DeSoto in Pinellas County this weekend. Didn't know we had any up this far.

Anonymous said...

Actually, this article has misinformed those who read it who have no prior knowledge about the caretaking of green iguanas. Having raised green iguanas for many years, I can correct the false information.

First: Iguanas cannot be kept in inexpensive tanks. Due to the great sizes they can grow up to (up to 6 feet) they require large enclosures, ideally about three times their tail length; about 6-9 feet tall.

Second: Iguanas must be fed every day to every other day. The function of their digestive system depends on their body temperature. If they are heated adequately, their digestive system will complete its digestive function and they will be able to eat every day.

Third: Iguanas, as easily as cats and dogs, can develop a loving relationship to its owner or caretaker. The main, #1 reason that iguanas are released into the wild is space and heating. Many iguana owners cannot afford the expensive electricity bill needed to heat the enclosure so they bring their iguanas to subtropical climates and release them, not realizing the consequenses.

The second reason for release is space. Iguanas require a lot of climbing space and large enclosures otherwise they can become very sick and die of illness or depression.

Agression in iguanas can come with personality, but mostly with upbringing. The reason they are aggressive in the wild is because they are now wild animals. If an iguana is brought up exposed to human contact from a young age, that iguana has a very small chance of becoming aggressive wtihout reason.

Here are the facts. I hope this clears up some falacies about the Green Iguana.

Anonymous said...

Iguanas are a major problem in South Florida. No question about it. Now, how can we get rid of them? Ah, that's the question...

A lot of Floridians have opted for purchasing a pellet air rifle over the internet or phone, and pumping the creatures full of steel BBs or lead pellets until dead. How is this good? It's very effective, low cost, and relatively easy. If people could hit them directly in the head, you could even consider it a humane elimination, because they would suffer. How this is bad? Since when is the average 50-80 year old Floridian any good at shooting? Getting a direct hit in the head is difficult. Doing it at enough range so they don't run is even harder. Pellet guns, because they often have to be cocked, are hard to sight in.

So, instead of a nice head shot, the hunters hit them in the body, and the animals bleed out. Even worse, whenever people actually do get a head shot, it isn't unusual for the iguana to still be alive and running. I've heard numerous stories were excellent head shots had to be repeated again and again because the first didn't kill the animal. So, use a bigger gun, like a .22... Right?

Wrong. It is illegal to discharge an active firearm on your property. Air rifles are considered dangerous toys, but are legal to discharge. So, get the most powerful air rifle possible. Generally, any spring action rifle that can propel a pellet at 1000+ are strong enough. But a lot of South Florida residents don't know about that. They purchase low-power air guns, and try to figure out why the animals are still able to crawl away with two dozen pieces of lead in them. Even worse, some (though thankfully not many) actually buy the Air soft varients, which fire plastic pellets that just bruise the Iquanas. Because these airsoft are automatic, these unlucky reptiles are peppered with little bruises.

Oh my God! What is the answer?! Well, you can set up traps. They're not as effective or easy as a rifle, but once caught, they can be taken to your local animal shelter. Heard you should freeze 'em? On second thought, a lot of biologists and vets are sayin' no. Why? Not humane. They aren't cold-blooded, their temperatures imitate the ambient temp, meaning that spot in the freezer is one tough highway to hell.

How about poison? Ouch. Talk about painful.

Is there an easy answer? Sort of. The most humane way is to trap them, and give them to a shelter. If you don't want to go to the trouble, there's the air rifle in the corner. Pellet manufactureres make special pellet varients designed with the idea of the killing small game and pests. One type is made out of a special alloy instead of lead, and it increases the power (velocity), penetration, and accuracy of the pellet. Then, there are hollow points, which have a pit in the tip that compresses air when impacting the animal, and causes the lead to explode inside the pest.

There is no perfect solution, because if there was we wouldn't have a problem. The only reason why half of Florida isn't toting their red ryders around the flower garden is because the law is a little fuzzy with shooting iguanas. They are considered endangered, and are protected. But then, the law enforcement rarely pursues shooters.

Who knows, perhaps the next hurricane will blow them away. But while you wait for the next natural disaster, try not to ensnare your own hand inside the traps... or try not to shoot your eye out, kid. :D

Anonymous said...

I did a science experiment for school and tested which home remedy is most effective in keeping iguanas from eating flowers in South Florida. The results were that putting mothballs around the plant worked the best. Second, putting garlic powder on the leaves and flowers worked second best. Placing an owl statute nearby the plant did not work very well.

Anonymous said...

Unless you are doing international trade in iguanas, CITES is irrelevant. CITES only governs international trade in listed species. It doesn't offer any protection to the animals already in the US.