The Isles of Scilly Seabird Recovery Project aims to build on the successful removal of rats from St Agnes and Gugh by extending rat eradication efforts to the remaining off islands. The project will also establish long term biosecurity and management measures to support sustained seabird recovery. As part of this work, funding from the Offshore Wind Industry Council (OWIC) was provided to assess the potential of habitats across the Isles of Scilly to support breeding seabirds in the absence of rats.

Field assessments were carried out in June 2025, involving comprehensive visual assessments of breeding habitat for all 13 seabird species that regularly breed in the Isles of Scilly. Particular attention was given to habitat suitability for guillemot and razorbill, both of which are currently the focus of specific compensation considerations. The report concludes an estimated 505ha of suitable ‘rat-free’ breeding habitat would become available following a rat eradication of St Martin’s, Tresco, Bryher and the associated islands. This would increase the total potential rat free breeding habitat across the Isles of Scilly to 619ha, with the capacity to support an estimated 40,000 breeding pairs of seabirds, assuming no other limiting factors