Blue Iguanas get helping hand to recovery
Another of the iguanas the people involved in the
breeding project concentrate on is the delightfully
Tuesday, April 26, 2005
The Blue Iguana (Cyclura lewisi) is found only on Grand Cayman and holds the unenviable position as the world’s most endangered iguana. Here we would like to tell you more about your iguana, what they are like and what they like, what challenges they face on the road to survival and how we are trying to help them on their way.
It all began in 1938, when the late Bernard C. Lewis from the Institute of Jamaica, joined an Oxford University Biological Expedition to the Cayman Islands. With difficulty Lewis collected two Blue Iguanas, a male and a female, which were later lodged with the British Museum (Natural History). Chapman Grant, in a monograph published in 1940, formally described the Blue Iguana for the first time.
Fifty years later, a British researcher was commissioned by the Cayman Islands Government to carry out a survey of the remaining Blue Iguana population. Roger Avery, in his report in 1988, came to a very similar conclusion. In two weeks of systematic searching in the east interior of Grand Cayman, he glimpsed only three iguanas. It was that same year that the National Trust for the Cayman Islands was formed.
A fruitful collaboration between the Trust and the US National Zoo began in 1991, when the Zoo’s then curator of reptiles, Dale Marcellini, visited Cayman and happened upon the Trust’s new Blue Iguana breeding facility. With funding from Friends of the National Zoo, the Trust and Zoo intern Kevin Gould began searching for clues on where the last of Cayman’s Blue Iguanas might be found.
Answers came from the farming community of East End, and by 1993 a study site with up to five wild iguanas was yielding the first information about population density, threats, diet, behaviour, and breeding in the wild.
In 1995 Kevin Gould working with the Trust’s Blue Iguana program director Fred Burton, estimated that there were approximately 150 Blue Iguanas still surviving in the wild.
In December 2001, Burton led a group of international volunteers on a new survey to assess changes over the past 6 years, to better characterize the area and habitat occupied by the relic population, and to assess the potential for establishing a protected area specifically for the Blue Iguanas. The results were a shock: less than 25 individuals were estimated to remain from the original wild population.
This news focused attention on the small released population which the Blue Iguana Recovery Program has established in the QE II Botanic Park. This group of about 30 individuals is now breeding successfully. In 2002-3 University of Tennessee Master’s student Rachel Goodman studied home ranges, habitat use and territorial interactions of this group. Her work yielded information which helped us assess the area of wild habitat which must ultimately be protected and managed to support a restored population of some 1,000 wild Blue Iguanas. The Blue Iguana Recovery Program is now breeding and rearing over 80 Blue Iguanas a year, with the potential to release over 80 two-year-olds annually into protected areas.
With the QE II Botanic Park now near its carrying capacity limit for Blue Iguanas, the Program is now restoring a second wild population, in the National Trust’s Salina Reserve. Longer term, additional managed Blue Iguana habitat will be needed, to reach a genetically stable population size in the wild.
From volunteer beginnings the work now requires a small core team of professionals, which needs a matching income stream. If the programme and its supporters can build sustainable economic activities benefiting the Blues, a high profile image for the species, keystone grants and steady science-based conservation work, we firmly believe we can save the Grand Cayman Blue Iguana. This is one species the world need not lose.
If anyone is interested in volunteering for the Blue Iguana Recovery Programme please call Chris on 925 4469 or Sam on 929 1678. For more information or to sign up for our beautiful quarterly newsletter please visit the programme’s website at
Next time…. ‘Don’t call me Green’ will describe the fundamental differences between the Grand Cayman Blue Iguana and the Central American Green Iguana.