Rare Iguanas Struggle for Survival as Island Population Grows

When a team of volunteers with the Blue Iguana Recovery Program arrived to work at their Grand Cayman Island breeding center last month, they were shocked by what they found: someone had savagely attacked the program's endangered reptiles, eventually killing seven. Investigators have found no suspects.

The killings were a major blow to the recovery of the rare blue iguana, found only on Grand Cayman, a 262-square-kilometer limestone outcropping in the western Caribbean. As few as 10 of the animals existed in 2002, but the breeding program has since increased the population to about 340.

The brutal attack, however, has brought considerable attention to the plight of the iguana. Donations have poured in from across the island and around the world. "We can't put value on the death of seven iguanas-that's infinite-but since it's happened we are managing benefits from it," said Fred Burton, director of the recovery program.

While the increased awareness is helping Burton improve security at the breeding center, the major threat to the iguanas may be a more difficult fix: human population growth. The rising number of human residents is a problem that is challenging the recovery of island species not just in the Caribbean, but around the world.

An influx of immigrants to Grand Cayman, which has among the world's highest living standards, has led population size to jump 32.5 percent since 2000, according to Caribbean Community Secretariat statistics. In recent decades, the iguanas were nearly driven to extinction with the construction of highways and the expansion of residential areas. As the number of residents continues to grow, these habitat pressures will likely continue.

Other island nations are facing similar challenges. Human populations in the Caribbean and Pacific are averaging a 1 percent annual growth, due in part to persistent high fertility rates and poor access to reproductive health services. On the Marshall Islands, Samoa, and the Solomon Islands in the Pacific, more than 40 percent of the population is younger than 15 years, according to Secretariat of the Pacific Community statistics.

The land and natural resources required by rising human populations, coupled with the pressures of global climate change and the spread of invasive species, have made island species among the most threatened in the world. Of the 724 recorded animal extinctions over the past 400 years, about half were island species, according to the Convention on Biological Diversity.

Recent conservation drives are beginning to preserve more island territory. Through the Global Island Partnership, a government-led initiative launched in 2006, Micronesia, Grenada, and Jamaica have promised that at least 20 percent of their terrestrial and marine areas will be protected by 2020.

In Grand Cayman, a new conservation law to be debated in the legislative assembly in August could lay the groundwork for a system of protected areas on the island. Meanwhile, the government has been negotiating an agreement that may set aside shrubland for the blue iguana. "What we need is an area of shrubland large enough to accommodate an estimated 1,000 animals to have a self-sustaining wild population," said Gina Petrie, director of the island's Department of Environment.

As the memory of the iguana attacks continues to resonate in the minds of Grand Cayman residents, support for iguana conservation remains high, Burton said. But he acknowledges that steady population growth leaves him with only a short window of opportunity. "We don't have a lot of time to secure the protected areas," he said. "If we lose a couple of years, we'll find the options we're looking at now won't be options anymore."

Ben Block is a staff writer with the Worldwatch Institute. He can be reached at bblock@worldwatch.org.