Ask Otus: Invasion of the Tegus!

Otus Rufous, an Eastern Screech-owl, was born on Siesta Key and is a full-time resident there. An avid hunter, accomplished vocalist and genuine night owl, Otus is a keen observer of our local wildlife and knows many of nature's secrets. Otus will answer your questions about our amazing wildlife, but only if you Ask Otus™.

Dear Readers,

Most of us Floridians have been anxiously following the national news coverage of the Sunshine State's latest invasive species: the exotic, destructive Giant Argentine Black and White Tegu. From Fox News and USA Today to the International Business Times (IBT), reporters are running with this latest story almost as fast as their subject. Philip Ross in IBT draws from many news sources and interviews with Florida Fish and Wildlife Conservation Commission (WFC) officials, and other government spokespersons to succinctly summarize the problem and the concerns it raises. His article is highly informative and scary. I shall draw from it and provide you the link to Mr. Ross' text at the end of this column.

"Large Black-and-White Tegu Invades Florida County And 'Eats Everything.'" Specifically, in the suburbs south of Tampa Bay, WFC has been monitoring a breeding colony of more than one hundred Black & White Tegus. WFC is setting traps to capture as many as it can. Collected tegus are euthanized and a necropsy is performed better to determine diet, health, and specifics of this lizard species. All better to understand your enemy and how to deal with it. This latest infestation of Black and White tegus follows others over a three-year period in Miami-Dade, Polk, and Bay counties (Panama City in particular). FWC's lone biologist assigned to monitor the Hillsborough County breeding grounds is also responsible for documenting the tegu population in Polk County. In Miami-Dade County, the FWC has partnered with the University of Florida. So many tegus; so few staffers!

Many nature-loving Siesta Key residents and visitors to our fair shores are anxious to see what a tegu actually looks like and learn why it causes ecologists, scientists, and government officials such concern. The handsome Black and White tegu photo (from Wikimedia Commons) accompanying Mr. Ross' article is of a tegu in the Buenos Aires Zoo. That is a long and expensive trip, especially during Mardi Gras, just to enjoy seeing a live one in the flesh. Alternatively, now that we are in High Season, who really wants to fight the traffic on I-75 to reach Hillsborough County's Teguland theme park? My suggestion on stress-free and low-cost travel is to walk out into your own backyard and look for one. Yes! Over the past few years, Siesta Key has been (and probably still is) home to not just one but to three species of tegus.--the Argentine Giant Black-and-White (Tupinambis merianae), the Columbian Gold (T. teguixin) and a hybrid tegu, (T. spp.), possibly a cross between the other, have all made their homes on Siesta Key. You didn't know that, did you? This is why you are reading this column — to be informed of what's happening in your very own backyard.

What is a Giant Argentine Black and White Tegu? Here is a photo of our most recent one. Note its huge red forked-tongue, which it uses to seek out its prey.

Tupinambis merianae is a big lizard native to east and central South America. The largest of the tegu species, the male can grow to 4.5 ft. As it is adaptable to such a wide range of habitats, from semi-deserts to tropical rain forests, and savannas, it is only natural it would feel quite "at home" in Florida. It excels at a variety of outdoor sports — swimming, tree-climbing, burrowing, and sprinting on its hind legs! In this video by Florida wildlife photo-documentarian-extraordinaire Ojatro you will see a juvenile pet tegu practicing its bipedal skills, while uttering odd-sounding grunts. My over-all impression of this lizard as a pet is that it does not play well with others! Watch video.

Tegus are omnivores. If they can fit prey into their mouths, it's a meal. The young begin by eating insects, berries, seeds, and fruit as they mature they need to supplement their diet with large quantities of meat and eggs. That means that they will devour our vegetation and fruit as well as gopher tortoises (shell and all!), other reptiles, small birds (that's me!), and eggs. You name the species' egg and they will hunt it down with that long, forked, probing red tongue and quickly devour it. In fact, FWC is actually using chicken eggs placed in traps to lure these tegus in. All our threatened and endangered species, from Burrowing Owls to Scrub Jays to Indigo Snakes, will haplessly provide them with their eggs (or even the parents themselves) just at the time when these lizards emerge hungry and randy from brumation (a reptilian form of hibernation). Brumation also raises the sexual hormone level of the males and enables him to provide the female with a clutch of anywhere from 25-50 fertilized eggs. So, let's calculate Hillsborough's dilemma. If you take 50 pairs of breeding tegus and multiply them by x by a couple of years ...

Why do we have tegus running wild around Florida's suburbs?

I neglected to mention that tegus are beautifully geometric-patterned lizards. You can see from this photo of our Siesta Key hybrid how exquisitely Mother Nature has crafted them. Thus, they are highly prized by collectors; not only for their markings but also for their reputation as a docile, tamable lizard — a very affectionate one that will actually seek out human companionship, even to the point of sitting on its owner's lap for cuddle-and-snuggle time.

These facts seem to belie the quote from Mr. Ross "... a striped four-legged reptile with a voracious appetite and a bite capable of turning human fingers into powder." It makes the wee beasties sound downright nasty! Well, until you read further ... "According to [FWC biologist Tessie] Offner, black-and-white tegus have highly acidic stomachs than can dissolve shells, including tortoise shells, and animal bones. Their powerful jaws can exert forces up to 220 pounds per square inch." So, the question remains ... how great is their appetite and how bad their bite?

Pretty large and pretty bad! The following video isn't for all viewers. It does, however, confirm my initial impression that a pet tegu "does not play well with others." In the video, a pet baby tegu has been given a live Blue-bellied lizard for its meal. The Blue-bellied is a type of spiny lizard, a beneficial insectivore, native and common to the American West. Its claim to fame is that it contains the spread of Lyme disease in the areas it inhabits. "When ticks carrying Lyme disease feed on these lizards' blood (which they commonly do, especially around their ears), a protein in their blood kills the bacterium that causes Lyme disease. The blood inside the ticks' gut is therefore cleansed and no longer carries Lyme disease." (Wiki) Rather cool factoid, but one quite irrelevant to this video.

Having watched both videos, you now understand why we have tegus running wild around Florida. Tegus are difficult for even the most experienced and loving pet owners to maintain. They require a large enclosed living space, an incredibly diverse diet, and lots of exercise to stay healthy. Handling them, especially when the male reaches a good size and sexual maturity, becomes problematic as aggression levels rise. And it is an exhaustingly repetitive chore cleaning their stinky cages. They are expensive pets to maintain. It is only natural that many loving owners, even breeders, although loathe to part with their tegus, simply choose to abandon them, even though it is illegal to do so, in the Florida "wilds" where tegus have no natural predators.

Are you now wondering if we have a breeding colony of tegus on Siesta Key?

I posit that due the appearance of various free-roaming tegus on our key over the past few years that conditions are highly conducive to such . The documented history of tegus dates from November 2007, when a Golden tegu appeared on the south end of the key. It was promptly nicknamed "Siesta Nessie." It disappeared after several months, after having devastated an entire colony of nesting Yellow-crowned Night Herons. At the time, no one took any interest, other than to dutifully register it into the data base. By August, 2012, with the fourth tegu sighting on Siesta Key, this time of an Argentine Black and White, the response from Sarasota County was immediate and impressive. The county dispatched an environmentalist to trap the lizard, and Mote Marine Laboratories instructed its turtle patrol to look for signs of lizard predation on sea turtle nests along Turtle Beach. Despite all efforts, the tegu was never found. or captured.

What do you do if you spot a tegu?

1) You must get a photo of it. You wouldn't believe how many lizards — from our native adult Five-lined skink to the Cuban anole — have been mistaken for baby tegus or Black Spiny-tailed iguanas. If you can't get a photo, write down the best detailed description you can. Also include the time and location of sightings.

2) Call FWC at 1-888-482-4681 to report your sighting. Or go online to the FWC website IveGot1.org to report and download your report and photograph. But a comment from me on that site ... Unless your website navigational skills are very good and your patience is endless," You can't get there from here!" was my frustrating experience with the site.

Once your sighting has been confirmed, you can really go into action!

3) It is very important to alert your neighborhood community to the confirmed presence of a tegu in your area. FWC will trap tegus on state land and, with the owner's permission, on private property too. Sarasota County is limited to trapping on county land; private landowners must hire a licensed trapper at their own expense. FWC maintains a list of licensed trappers. So, the more people in your community who know that a tegu exists in your neighborhood, the better the information you all can provide to authorities on its location. And, neighbors will often offer to chip in to share the cost of a private trapper! You don't know your neighbors? No problem! With all the monies I've saved you on travel to Rio or Hillsborough to see a live tegu, you can all afford a friendly gathering of Concerned-Citizens-Against-Tegus at Another Broken Egg Café to get to know one another and to discuss the problem, while enjoying a good epicurean omelet. But be sure to get there before the tegus sniff out those broken eggs!

Finally, for further details on Florida's wild world of tegus ... here is the great article on our Florida tegu infestation by Philip Ross.

Otus