This captivating blog post explores the remarkable discoveries about the importance of the Lesser Antillean iguana within the delicate Caribbean ecosystems. Delve into the fascinating pilot study that unveils the intricate web of interactions between the iguana’s nests and a diverse array of plant and animal species, highlighting the iguana’s keystone role as an ecosystem engineer. Understand the alarming decline of this critical species and the potential cascading effects on the native flora and fauna of the Caribbean islands.
Discovering the Mysteries of Iguana Nests: An Eclectic Paradise
New research 03 July 2019 A small pilot program on the Caribbean island of Sint Eustatius has revealed something truly remarkable: the nests built by lesser Antillean iguanas, the largest native land animal on the island, act as critical stepping stones for scores of other plants and animals. But inside these networks of fully excavated tubes and chambers, the territory is divided not just by the iguanas.
Digging into the nests, the researchers found that these spaces are used by a variety of creatures—including lizards and tarantulas, crickets, and even black land crabs. For example, the ameiva lizards use them to lay eggs and to hunt as well as thermoregulate, and a wide array of invertebrates lives inside these subterranean abodes. The find highlights the important function of the iguanas as ecosystem engineers — they create the kinds of habitats that help native species thrive, and contribute to a healthy Caribbean ecosystem.
Revealing the Hidden Complexity of Iguana Nests
These iguana nests were excavated with all the caveats has shown us just how elaborate and extensive these things can get. The scientists searched for nesting chambers and found that, contrary to earlier assumptions, they can be up to 1.65 meters below the surface with tunnels extending 6 meters in length. Females dig and cover nests above ground in sand near the site of egg incubation; larger nesting areas encompass dozens of square metres and may have been used by many female lizards across several years, producing a network of entrances, tunnels and chambers connected underground.
Such complexity underscores the adaptiveness of iguana life and its importance in creating local conditions. They are in effect allowing diverse and large habitats for a host of other species, from their reptile brethren to many invertebrates. The iguanas are ecosystem engineers, and as the biggest land animals on Sint Eustatius, their role in combination with the loss of other native animal species has wide-ranging implications for island ecology.
The Lesser Antillean Iguana: A Story of Collapse… and Perspective
Given the vital role of the Lesser Antillean iguana in Caribbean ecosystems, it is ironic that this species is threatened with extinction. Since the 1990s, small population of Sint Eustatius has been dwindling to critically low levels due to illegal trade and consumption, and habitat destruction facilitated by free-roaming livestock and invasive species along with coastal development.
As the study reports, not only iguanas themselves or their future generations have to face the outcome of decreasing population as it becomes apparent that consequences are likely far-reaching to species — including birds and plants apart from land crabs which relied on iguana nests and the mosaics of burrows they create. This means the disappearance of these iguanas on Sint Eustatius could have an even greater impact than first thought, with all these interactions being mapped out by the researchers. Research is still needed to understand the full implications of this and other disturbances on these ecosystems as well as what can be done to help protect this important species and the fragile Caribbean systems supported by them.
