Why TCI tourists should avoid feeding rock iguanas.

By Mel DeBlasio (Yale University), Libby Dube (Western Washington University), and Anna Templeton (University of Vermont) ~ Edited by C.E. O’Brien, Ph.D. (The School for Field Studies, Center for Marine Resource Studies, South Caicos, Turks & Caicos Islands)

Visitors flock to the Turks & Caicos Islands to enjoy the white sand, sunny weather, and calm surf, but they aren’t alone on these picturesque beaches. The Islands are also home to an incredible array of native flora and fauna, which, in contrast to the transient tourists, live year-round in the small but rich island ecosystems.

A distinctive resident of the Turks & Caicos Islands is the Turks & Caicos rock iguana.

One particularly noticeable resident is the large Turks & Caicos rock iguana. Although their long tails, scaly skin, and big claws make them look like invincible predators, the species is actually critically endangered according to the International Union for Conservation of Nature (IUCN) and very susceptible to human and environmental disturbances. The reptiles were once widespread across Turks & Caicos, but can now only be found on a few isolated cays.

According to an evaluative study conducted in 2002, rock iguanas had disappeared from 13 of the islands in the Turks & Caicos that they once inhabited. Not only is this bad news for the iguanas themselves, but it’s also devastating for the ecosystems they inhabit. Iguanas play an essential role in maintaining the environment for the other plants and animals that share their space. For example, native plants rely on iguanas to spread their seeds across large distances. The iguanas nibble on the plants in one location and excrete the indigestible seeds in a new location. They also dig up the ground to make their burrows, mixing oxygen and nutrients throughout the soil. As a result of these important behaviors, when the iguana population declines the whole native ecosystem suffers greatly.

Organizations from Turks & Caicos and abroad have been working for years to restore the iguana population, reintroducing them to uninhabited cays and protecting them where they do occur. In the past, these iguanas were hunted by feral cats and dogs, as well as humans. These days, iguanas face a friendlier, but nonetheless dangerous, threat. Tourists encountering these intriguing animals on vacation are inclined to feed them, a widespread practice referred to as “provisioning.” But despite good intentions, provisioning can have disastrous consequences for the TCI rock iguana and wildlife in general.

In other animals, provisioning can lead to a host of negative consequences. For instance, researchers have found that a history of human feeding has made members of the population of bottlenose dolphins in Sarasota Bay (Florida) inclined to seek interaction with fishers, boaters, and tourists. This has led to an increase in the rate of injury to these dolphins through entanglement with fishing gear and collisions with boats. Similarly, a study of Barbary macaques in Morocco demonstrated that provisioned populations experienced higher stress levels and hair loss. Studies of birds have found that provisioning can negatively impact health due to the inappropriateness of the food provisioned (bread is not good for most birds!) and the disease and parasite transmission that can occur between individuals when they are congregated at unnaturally high densities around a food source.

Wildlife provisioning may have negative consequences for humans as well. In Thailand, during the COVID-19 lockdown, residents were inundated by hordes of scavenging long-tailed macaques, whose populations had been unnaturally boosted by food from the now suddenly absent tourists. These hungry monkeys rampaged through city streets, rooting through trash and entering homes and businesses in search of snacks, sometimes driving residents and business owners away. Large “brawls” often erupted between the monkeys over scraps, including one caught on video that involved hundreds of individuals fighting over a single empty yogurt cup. To control the population and reduce the mayhem, officials were forced to capture and sterilize over 500 individuals.

In a touristed area, five iguanas rapidly approached visitors without fear.

To determine the effect that provisioning has on the normally timid and evasive TCI rock iguanas, researchers gathered data on the behavior and number of iguanas in two areas located within one kilometer of each other on an uninhabited cay. One of the areas is very popular with tourists, and the other is rarely visited. The researchers walked through three types of sub-habitats: sandy beaches, dense shrubbery, and rocky cliffs. In the more rugged non-tourist area, the iguanas exhibited skittish behavior. Researchers only saw one rock iguana, in the act of running for its life, and the rest of their few encounters were only the unmistakable sound of scuttling feet in the bushes. In all of eight quick interactions, the iguanas in the less-touristed area displayed their normal fearful and protective attitudes, fleeing from potential danger.

Only a short distance away in the more-touristed area, however, there was an extreme shift in iguana behavior. Many more iguanas were observed, and they were more aggressive. Three times as many interactions were logged. During most of these encounters, the researchers were able to see and maintain prolonged eye contact with these bold reptiles, not unlike a Wild West stare down. Iguanas in this area approached researchers with fearless determination, lingering around every turn to beg for food. This food-seeking behavior is typical of rock iguanas: once they locate a food source, they are known to return to that site frequently. The longer researchers stayed in the tourist area, the more iguanas could be seen lurking and looking for snacks.
The researchers also noted that 86% of all iguanas encountered at both sites were found within or around the dense shrubbery just upland of the beach.

On the non-tourist beaches, this sub-habitat was dense, overgrown, and practically impenetrable. On the tourist beach, however, the shrubbery was intersected by a wide and heavily traversed path. Not only does this walkway disruptively bisect the iguanas’ habitat, but it also gives humans unhindered access to their preferred hiding spaces. These invasive man-made developments increase the chances of human–iguana interactions even more.

This investigation made it apparent that the iguanas subject to feeding from tourists had entirely different behavior from those who were not accustomed to human visitors. This is an important finding for multiple reasons. First and foremost, these interactions pose physical threats to both humans and iguanas. In the touristed area, iguanas were bold and even demanding, waltzing right up to the researchers and sometimes scratching or biting them. Provisioned iguanas also tend to fight amongst themselves over food, depleting energy reserves and potentially resulting in injuries. Finally, humans may directly harm iguana health by unknowingly feeding them foods that are harmful to them and by leaving behind trash that iguanas mistake for food.

Additionally, provisioning can affect the whole ecosystem, as iguanas not only feed themselves but also nourish the environment with their way of living. If they start relying on humans to give them bananas, potato chips, and other snacks they can’t find at their natural grocery store, they’ll stop eating native plants. If they stop pruning shrubs and spreading seeds, these plants, such as the seven year apple, an important food source for native birds, and torchwood, which has a dense root system that protects against beach erosion, will no longer grow and flourish. Iguana populations will dwindle as their habitat becomes sparse and barren, unable to sustain themselves on exclusively processed foods. Protecting iguanas is therefore essential to protecting the vibrant and rich ecosystem of the Turks & Caicos Islands.

So, what do these findings mean for future visitors to Turks & Caicos? If you plan on enjoying the Islands, it’s important to be mindful of the native wildlife. While the local critters may seem friendly and eager to accept food from tourists, remember that they are still wild animals. These scaly little creatures deserve to have their homes and personal space respected.

This adult male Turks & Cacios rock iguana watches visitors approach as he perches upon a conch shell.

If you are visiting one of the cays where they occur and you’d like to see an iguana in the wild, pick a sunny day and try sitting quietly and still at ground level within eyesight of dense shrubbery, their favorite hiding spot, keeping an ear out for their telltale rustling noises. This way, you have a higher chance of observing the iguanas without disrupting their normal daily activities. The best spot to do this is on Little Water Cay, also known as Iguana Cay, part of the Princess Alexandra Nature Reserve and located a short distance northeast of Providenciales. Elevated boardwalks allow visitors to traverse the island without disrupting the habitat. If you do visit Little Water Cay, make sure you leave your pets at home, as dogs and cats still pose a threat to these recovering populations. Also be sure not to stray from the boardwalk, and to collect and remove food wrappers or other litter that could be eaten by iguanas. And of course, NO FEEDING THE IGUANAS!

By being considerate of the local ecosystem, we can help ensure a safe and enjoyable trip for ourselves and for the creatures that call these places home. It’s best to let them interact naturally with their environment and find their own food sources—so keep your bananas and potato chips to yourself!

For detailed article references or more information about The School for Field Studies, contact Director Heidi Hertler on South Caicos at hhertler@fieldstudies.org or visit www.fieldstudies.org.