Adult blue iguana on Grand Cayman Island

Saving the Beautiful Blue Iguana

Joan Maurer holds a cloth iguana she made for conservation talks
In front of the Milwaukee County Zoo’s blue-iguana exhibit, Joan Maurer holds a cloth iguana she made for conservation talks.

Joan Maurer held up a huge blue iguana. She made it herself. She hand-painted the color and the eyes onto the cloth. It’s the size of a mature, 7-year-old, female blue iguana. Yes, they really get that blue. “I’ve seen them,” she says. It looks a lot like the ones she helped protect in the Caribbean since 2009. She uses this prop when she speaks to Zoological Society of Milwaukee classes at the Milwaukee (Wis.) County Zoo or to kids at Milwaukee-area libraries. This had been one of the most endangered lizard species in the world, she tells them. But many volunteers – including Maurer and two other Milwaukee County Zoo staff* – helped bring this iguana back from near extinction.

For a week in June 2012, Maurer volunteered with the Blue Iguana Recovery Program on Grand Cayman Island, the largest of three Caribbean islands that are a British Overseas Territory. Maurer is a veterinary technician at the Milwaukee County Zoo. She brought her medical and research skills to the Queen Elizabeth II Botanical Park, where she worked from 8 a.m. to sometimes 9 p.m. doing iguana health exams and lab analyses. The 82 young iguanas had been hand-raised at the park to about age 2. This “head-start” lets them grow big enough to avoid predators (snakes, cats, dogs) when they are released into the wild. Maurer assisted with collecting measurements and photos, placing transponder chips into the youngsters and threading colorful beads through their thorny crests so the iguanas could be identified from a distance. “One of the youngsters had a hernia; so we did a surgical repair on site,” she says. 

“What’s most fascinating is the effort that goes into this recovery program,” she adds. Iguanas dig underground, lay their eggs and then seal up and disguise the den entrance. Park wardens retrieve these eggs, place them into humidity- and temperature-controlled incubators for 65 to 90 days, travel the island to collect natural foods for the hatchlings, and then care for the young for approximately two years. They also build “hidey” boxes, or homes, for blue iguanas to retreat to when they’re released into one of three wildlife preserves on the island. Maurer was part of the veterinary support coordinated since 2001 by the Wildlife Conservation Society (WCS), a national conservation group with headquarters in New York City. Dr. Paul Calle, WCS chief veterinarian, leads the veterinary part of the conservation effort. Maurer’s trip was supported by the Zoological Society of Milwaukee and the Milwaukee County Zoo.

A young iguana has colored beads in its crest to identify it
A young iguana has colored beads in its crest to identify it.

Maurer, who has done volunteer research in the Cayman Islands for the last four years and at the International Crane Foundation in Baraboo, Wis., with endangered whooping cranes, says she likes collaborating with other veterinary staff and researchers. “I learn firsthand what it takes to run a successful recovery project for an endangered species.” In the mornings on Grand Cayman, Maurer would participate in the project by assisting with iguana health exams. A typical physical exam would identify each animal, obtain blood and fecal samples, collect weights and measurements, determine gender, and check the animal’s condition, including the eyes, mouth and appendages. Finally, the team would photograph each animal because each iguana’s scale pattern is unique – just as human fingerprints are. Photos create a visual record of each iguana’s identifying scales and other characteristics. In late afternoon to early evening, Maurer would work in the laboratory at St. Matthews Veterinary School on the island, performing blood analyses, banking samples for later analyses and processing fecal samples to check for parasites.

An iguana hatches from incubated eggs
An iguana hatches from incubated eggs

A relatively new conservation challenge for the blue iguana is the green iguana. It’s believed that the green iguana was introduced onto Grand Cayman during Hurricane Ivan in 2004. Unlike the blue iguanas, which may have from one to 21 eggs per clutch, the green iguana can have up to 50 eggs. So now there are thousands of green iguanas that are not endangered and are popping up on the island. In particular, the greens can be found on swimming pool patios and decks, where they leave large deposits of poop. The greens are prolific, they’re a nuisance and they create confusion because the casual observer cannot differentiate between the blue and green iguana, says Maurer. The few wild blue iguanas found in human habitat risk being hunted and killed. The head-start blue iguanas, however, are released into two difficult-to-access reserves on Grand Cayman that have very harsh habitat unfriendly to humans. “The ground is sharp as glass because it’s limestone rock, composed of skeletal fragments of ancient reefs,” says Maurer. “One week’s wear in the field can destroy a typical pair of work boots.”

The blue iguana has made an amazing comeback due to this successful head-start conservation program. The species lives only on Grand Cayman, and the recovery program is run by the National Trust for the Cayman Islands. By 2002, there were fewer than 20 blue iguanas left in the wild! “As a result of the recovery effort…there are now more than 700 free-ranging Grand Cayman iguanas at three sites on Grand Cayman,” reports a 2012 WCS update. The goal is to reach 1,000. “This is one endangered species that CAN be saved,” writes Frederic J. Burton, the director of  the island’s wildlife reserves and author of “The Little Blue Book: A Short History of the Grand Cayman Blue Iguana” (2010, International Reptile Conservation Foundation). Says Maurer: “Just being part of such a successful program, I feel honored.”

More Photos

Dr. Paul Calle and Joan Maurer draw blood from a young iguana Work shoes have ripped soles after just a week in a limestone wildlife reserve Joan Maurer at a microscope on Grand Cayman These hand-crafted wooden homes go with young iguanas to reserves

By Paula Brookmire

* Stacy Whitaker is a Milwaukee zookeeper who has volunteered with the Blue Iguana Recovery Program since 2006 and assisted with the Little Cayman rock iguana project in 2012.

Craig Pelke, a past zookeeper, volunteered on Grand Cayman for several years. And zookeeper Dawn Fleuchaus has been involved with conservation of the Jamaican iguana since 2002..