At a time when much of Cayman’s wildlife is still reeling from the effects of Hurricane Ivan, some good news comes from the Blue Iguana Recovery Programme.
Twenty three iguanas were released last month, into the National Trust’s Salina Reserve, in an attempt to boost the catastrophically depleted wild population. Recent surveys estimate the number of wild iguanas to be as low as 10-25 individuals, so this release effectively doubles the number of wild Blues.
To encourage the Blues to take up residence in the reserve, artificial iguana condos called ‘retreats’ were constructed, and laboriously backed over the rugged terrain to suitable spots. In this dry, rocky shrubland, iguana’s favour a habitat ‘mosaic’ of open soily pieces, which the females use to nest in, interspersed with patches of vegetation, which provide them with food and shade.
Following the tradition of ladies first, seven two-year-old females were housed in retreats in the north of the reserve and six more in the centre. This, however, was just the start of the work. Radio transmitters were fitted to each iguana, to monitor their comings and goings while they settled into their new homes. They were then tracked, every day, from dawn to dusk, by a team led by Program Director Fred Burton, with support from BIRP staff Chris Carr and Samantha Addinall, and CI Department of Environment staff, John Bothwell and Janice Blumenthal.
The intensive field work was also well-supported by overseas participants, including Sarah Doty and Desiree Wong (International Reptile Conservation Foundation), Judith Bryja (Houston Zoo), John Kunna, and Craig Pelke (Milwaukee County Zoo), under the coordination of the International Reptile Conservation Foundation. Each paid their own way, or was funded by their respective institution.
The remainder of the project was funded by grants from the Dennis Curry Charitable Trust, through the Durrell Wildlife Conservation Trust, and the International Iguana Foundation.
After the ladies had had a few weeks to make themselves at home, the time was right for the males to make their bid for freedom.
Ten males, also two years old, were released into the mosaic habitats at the end of December.
Dawn-to-dusk radio tracking continued, now with all 23 iguanas being relocated at least once per hour.
The idea behind this staggered matchmaking was to allow the females to establish stable territories, which would then serve to anchor the more free-roaming males into the comparative safety of the reserve. ‘So far, the strategy seems to be working’, said Fred. ‘The girls have grown very attached to their new homes, and are already getting to know the boys’.
At the current time, all 23 pioneer iguanas are alive and well.
The intensive tracking was completed at the end of January, and now daily checkups will continue until the batteries on the radio transmitters run out in a few weeks.
If all continues to go according to plan, it is hoped that the females will nest for the first time this coming summer.
The Salina population will then represent only the second wild-breeding population in Grand Cayman, protected in a small part of the wild landscape that was once their ancestral home.