Above picture: A view of Floreana Island; photograph from Island Conservation

Encouraging news comes from Floreana Island in the Galapagos Islands, where early signs following a recent eradication operation look promising.  Rodenticide bait was applied on three separate occasions over the island in an attempt to ensure that every invasive Black Rat Rattus rattus and House Mouse Mus musculus came across the bait (read an earlier description of the baiting operation in MFM News).  A full suite of monitoring and detection tools is now being used, including bait stations, trail cameras, a thermal imaging drone and detection dogs, to look for any signs of rodents remaining on the island.

The Galapagos Conservation Trust has reported: “Last October, the restoration of Floreana Island reached an exciting milestone, as the eradication of over a decade in the planning, finally began.  The project, led by the Galapagos National Park and the Galapagos Biosecurity Agency in partnership with the Floreana community, co-executed by Fundación Jocotoco and Island Conservation, and supported by Galapagos Conservation Trust, Durrell Wildlife Conservation Trust and others, has as its ultimate aim the reintroduction of 12 locally extinct species and the restoration of the island’s degraded ecosystem.  The removal of invasive species is key to the project’s success, and initial indications regarding the eradication of rats and mice, which concluded in December 2023, are positive.”

The Large Ground Finch Geospiza magnirostris is intended to be reintroduced to Floreana; photograph by Tim and Kate Bradley, from the Galapagos Conservation Trust

With the eradication attempt showing promising signs (although a formal announcement of success would usually wait for two years with no signs of rodents) the decision was made to release the endemic Galapagos finches which had been kept in temporary captivity in aviaries on the island during the baiting operation.  Five species of Galapagos finches totalling five individuals were released in batches over January and February this year into their natural habitats on the island.  Some of the released birds were radio tracked to assess if it was safe to release all the birds.

Kelly Hague of the Galapagos Conservation Trust writes to MFM News: “It is still early days, and our fingers remain tightly crossed because, if this eradication has been successful, the impact could be huge for the 55 threatened species living on the island.  It would be so wonderful to see numbers of threatened birds, such as the Critically Endangered Galapagos Petrel Pterodroma phaeopygia, start to increase.  We were astonished to hear that Near Threatened Galapagos Doves Zenaida galapagoensis have already returned to the island and commenced breeding.  Island eradication projects can make a huge difference very quickly if they are successful, but they often require a doggedly, determined effort over several years to make sure this happens.”

Floreana is an inhabited island with a human population of 160.  Let’s hope the rats and mice have definitely gone, so that it can join Australia’s inhabited Lord Howe Island, now thankfully free of its rats and mice, as yet another success for what must surely be one of the world’s most important conservation activities: ridding islands of their introduced predators.

This promising early indication of the absence of rodents on Floreana is welcome news following the failed mouse eradications on Gough Island in the South Atlantic in 2021 and Midway Atoll in the North Pacific in 2023.  It will help inspire future endeavours of this type, including on Marion Island, where the Mouse-Free Marion Project team is working hard to eradicate the island’s House Mice.

With thanks to Kelly Hague, Senior Philanthropy Manager and Tom O’Hara, Communications Manager, Galapagos Conservation Trust.

John Cooper, News Correspondent, Mouse-Free Marion Project, 03 April 2024


A Northern Giant Petrel broods its chick on Marion Island; photograph by Janine Schoombie and poster design by Michelle Risi

The Mouse-Free Marion Project is a registered non-profit company (No. 2020/922433/08) in South Africa, established to eradicate the invasive albatross-killing mice on Marion Island in the Southern Ocean.  The project was initiated by BirdLife South Africa and the South African Department of Forestry, Fisheries and the Environment.  Upon successful completion, the project will restore the critical breeding habitat of over two million seabirds, many globally threatened, and improve the island’s resilience to a warming climate.  For more information or to support the project please visit mousefreemarion.org.