RAPID RODENT RESPONSE IN THE GALAPAGOS

RRF is helping to prevent an invasion of rats on North Seymour Island in the Galapagos, a UNESCO World Heritage site, from devastating the delicate island ecosystem and its world-famous wildlife.

The Galapagos Islands have been described as a ‘living museum and showcase of evolution’.

The biodiversity of the Galapagos needs little introduction. The isolation of the islands has resulted in a rich diversity of endemic plants and animals, such as the highly unusual flightless cormorant, giant cacti and marine iguana. The diversity of finches and mockingbirds famously inspired Charles Darwin’s theory of evolution by natural selection.

North Seymour Island in particular is important for the tourism economy in the Galapagos, due to its accessibility and amazing wildlife. The island’s complex ecological system is intertwined with the surrounding ocean, and is vital habitat for breeding seabirds (frigates, blue-footed boobies, Nazca boobies and swallow-tail gulls among others).

Invasive rodents can devastate native habitats and seabird colonies.

While rats are present in parts of the Galapagos, North Seymour Island had been rat-free since a successful eradication initiative in 2007. However, in 2018 invasive rats were detected on the island, and by August a state of emergency was declared by the Galapagos Ministry of Environment. Rats thrive on whatever food is available, from bird eggs to plant vegetation. They reproduce extremely quickly and lack natural predators in the Galapagos. Ground-nesting seabirds such as those found on North Seymour are particularly vulnerable to the devastating impact caused by rats.

Island Conservation (an NGO that specialises in eradicating invasive alien species from islands) responded to the crisis by developing a rat eradication plan, working the Galapagos National Park Directorate (GNDP). Timing of this work is critical, as implementation must occur during the dry season (October to January) when the rats are not reproducing, numbers are low and there is not enough natural food available on the island so rats are more likely to consume poisoned bait. RRF provided a grant of $14,240 to Island Conservation to enable the eradication to go ahead as quickly as possible.

The development of a mitigation plan for land iguanas (to avoid accidental poisoning) is also a vital aspect of this work and will be carried out through a collaboration of IC, University of Massey and GNPD. Bio-security measures will be put in place to minimise risk of re-invasion, such as baiting the near shores of neighbouring islands.

Swift implementation of these actions will prevent the rodent invasion from causing potentially irreversible damage to this fragile ecosystem and surrounding marine habitat. Moreover, this is incredibly important for the economy of the archipelago, which relies heavily on income from tourism. Ultimately, this will protect this World Heritage Site and the incredible array of unique species it supports.

Rapid Rodent Response in the Galapagos