Iguanas from Above

Endemic to the Galapagos Islands, Marine iguanas (Amblyrhynchus cristatus) are the only lizards in the world with the ability to live and forage at sea. They live only on the Galapagos Islands, and like many Galapagos species, they have adapted to an island lifestyle.

Populations across the archipelago have been isolated from each other for so long that each island has its own subspecies. Each of the 11 subspecies is vital to the survival of the species as a whole. Despite their isolation, they are listed as Vulnerable to extinction on the IUCN Red List, and face numerous growing threats including invasive species, pollution, and climate change.

Marine iguanas inhabit all 13 main islands in Galapagos, often in locations where high cliffs and wild waves make boat landings impossible, which means that some colonies are completely inaccessible by foot. Until now, it has been difficult to undertake an Archipelago-wide survey of the species due to logistical challenges. However, technological advances offer new ways to tackle old problems.

A Galapagos marine iguana basking on lava rocks.

USING NEW TECHNOLOGY TO REVOLUTIONIZE & ENABLE EFFECTIVE CONSERVATION

Iguanas from Above (IFA) founder Amy Macleod and her team are pioneering a new aerial method to undertake marine iguana population surveys using drones flown from boats. By flying drones above iguana colonies, the team is able to take photos which provide a more accurate count of iguana populations. The use of drones for purposes of conservation required careful development as it had never been done before.

Iguanas from Above researcher Amy Macleod climbing lava rocks to sample on Darwin Island.

Iguanas from Above researchers preparing for another drone launch.

Researchers training with drones to complete iguana survey samples in the Galapagos.

In the Field: Researchers preparing for one of many drone boat launches.

After receiving a grant from the International Iguana Foundation, the IFA team launched their first pilot study in December 2019 to show that the use of drones, as well as counting the famously well-camouflaged lizards on their lava rock habitats, proved more efficient than traditional surveying. In order to speed up the latter, the IFA are currently investigating whether citizen scientists can reliably help via a project on Zooniverse.org, a citizen science portal.

Preliminary results have been promising and the team is excited to implement a new method for counting iguana populations via machine-learning.

RECENT FINDINGS

In December 2021, the IFA team completed their third successful field season. During the expedition, six team members used drones from a live-aboard sailing boat and a small rubber dinghy to gain access to the most remote parts of the Archipelago – allowing the team to collect information from the least well-known populations of marine iguanas. Because the drones enable the team to reach places that were inaccessible by traditional means, the IFA is finding colonies in locations never recorded.

In the Field: An Iguanas from Above researchers launching a drone from a boat.

Drone images of Galapagos marine iguanas on Fernandina Island.

“It’s exciting to be leading a project that embraces technology for the purposes of protecting both wildlife and people, and I’m grateful to organizations like the International Iguana Foundation and Galapagos Conservation Trust, who have supported our bold experiment and others like it.”

IFA is completing surveys of the remaining few islands and hope to complete analysis soon after; they are on track to reach their goal of publishing detailed population size estimates for all subspecies by 2025. It is suggested that this approach could greatly facilitate conservation in Galapagos. The team is working directly with Galapagos National Park managers to develop drone protocols for future monitoring.

Get involved

The team is continuing the monitoring project on Zooniverse.org. You can find it under Iguanas from Above or click here. Alternatively, visit the Iguanas from Above website to join the mailing list and be alerted when new phases are launched.