Above Picture:  The mouse captured on camera on Gough Island in December 2021; photograph by the Gough Island Restoration Programme

The Gough Island Restoration Programme (GIRP) aimed to eradicate introduced House Mice on Gough Island in the South Atlantic to protect the island’s birdlife.  Following the completion of the bait drop by helicopter in July last year, the situation looked promising until a single mouse was seen on a camera trap in mid-December.  Now more live mice have been recorded on the island as GIRP has reported on its website:

“Since we reported the camera trap footage of a mouse on Gough in mid-December, our team on island has been running a targeted monitoring and response operation to assess the extent of mouse presence across a range of locations and intercept any individuals identified. This work remains ongoing. The team has unfortunately caught a further four mice in two other locations. These records of multiple mice mean that the Gough Island Restoration Programme has not been successful in its primary objective to eradicate every single mouse from Gough, although it will bring some respite from the immense predation pressure experienced by the birds there.

At this stage, our focus is on trying to gather as much information as possible as to how widespread mouse survival may be on the island, and across which habitats and elevations. This may help us understand the more likely cause(s) and possible ways to amend the operational approach in light of any findings so that a renewed attempt at eradication may be made at some point in the future. We will make sure that every lesson possible is learnt, not just to benefit future RSPB efforts, but those of the wider island restoration community.

The RSPB remains resolute in its commitment to see Gough restored, and to other eradications more widely including Henderson Island in the Pacific and will continue to work closely with our partners.

While we wish we could be sharing more positive news at this time, we want to express our deep gratitude to all those who have supported the Gough Island Restoration Programme.  We will endeavour to keep you all updated as and when we have further significant information.”

Anton Wolfaardt, Mouse-Free Marion (MFM) Project Manager, writes “The latest news from Gough that a further four mice have been caught is truly devastating, and we once again empathise with our colleagues from the Royal Society for the Protection of Birds (RSPB) and the Gough Island Restoration Programme.  The planning, commitment, skills, and execution of the Gough project were exemplary, and this is certainly a bitter outcome.  This unfortunate outcome highlights that there are no guarantees of success with these large-scale island eradications, and that each eradication attempt, and island, is different.  We commend the RSPB for the work they are now doing to try and understand what might have led to the survival of these mice, and for their continued commitment to see Gough restored and to provide information that will guide other eradication efforts.  Over the last 20 – 30 years, rodent eradications on islands have been implemented more widely, and at increasingly large scales. In each case, operations have been informed by lessons learned and experience gained from earlier eradication attempts, both successes and failures.  The finding from Gough does not negate the selected methodology, nor the ecological need, for the MFM Project. The MFM Team will continue to work closely with our RSPB colleagues to learn from their experience and reviews, and to incorporate any lessons into our planning for the MFM Project.

John Cooper, News Correspondent & Member, Scientific and Technical Advisory Group, Mouse-Free Marion Project, 20 January 2022