Formica rufibarbis

Range & Status

Declining nationally, currently confined to Surrey and the Isles of Scilly, and considered by Pontin (2005) to be perhaps the rarest resident animal in mainland Britain. There were only four nests in Surrey in 2004. This species was considered by Shirt (1987) to be RDB3, but Falk (1991) revised it to RDB1. There is currently a conservation plan to remove queens from the Isles of Scilly for establishment in Surrey. Queens were collected in 2007 and 2008 and released at Surrey sites, where some at least of the colonies were probably attacked by Lasius niger .

Regional Distribution

The status in Cornwall currently unknown, but almost certainly extinct. It was last recorded in Cornwall at Whitsand Bay in 1907. This species is easily confused with Formica cunicularia , a common coastal species which can be separated from F. rufibarbis by the lack of hairs on its prothorax (although the queens are more easily separated). F. cunicularia is widespread around the Cornish coast in warm areas. Recorded on St. Martin' s, the Eastern Islands and Tean (Parslow, 2007). In 2008 approximately 70 nests were found on the island of St. Martin' s with reported nests on Great Ganilly, Tean and Nornour (Hymetus Ltd, 2008).

Habitat & Ecology

Found on the Scillies on open heathland with plenty of bare ground.

Threats

Considered by Spooner to be under threat from Formica fusca , which he considered was supplanting F. rufibarbis on the Isles of Scilly (Spooner, 1968).

Conservation

Listed as a BAP species with a species action plan. It has been recommended that further surveys are carried out on the Isles of Scilly in 2009 and further ants are collected for genetic analysis (Hymettus Ltd, 2008).