The Suffolk Argus
Special Edition - Summer 2008
The Team
The Role of Ants
The translocation was organised jointly by the Suffolk Branch of Butterfly Conservation and the Suffolk Wildlife Trust.
H. Taylor R. Turner
The team involved in this project includes a few permanent members of staff of Butterfly Conservation, the Suffolk Wildlife Trust and the RSPB, but the majority of the team were volunteers from those organisations and the Suffolk Naturalists’ Society. Although the actual translocation was completed in 2007, the ongoing monitoring and site maintenance will require an enthusiastic volunteer team for years to come. The existing local SWT group at Blaxhall Common will continue doing the site management, and their leader, Terry Peake, will also organise the new transect walk. Those who have participated to date include: Blaxhall SWT Volunteers T. Peake (Warden) A. Chapman J. Day S. Exton J. Forbes M. Forbes A. Freer S. Freer G. Haywood-Smith L. Merrion F. Pynn A.Salisbury
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Butterfly Conservation M. Austin M.Farrow J. Foster R. Foster A. Johnson B. Johnson S. Keeley R. Parker S. Peck G. Proctor S. Wolfe SNS Mr. Blacker Snr N. Blacker N. Cuming N. Mahler Other SWT N. Mason (Hollesley Warden) K. Thacker S. Thacker Staff Participants R. Harvey (RSPB), M. Kemp (RSPB), D. Kidney (Natural England), D. Mason (SWT), S. Hearle (Butterfly Conservation)
The Silver-studded Blue (Plebejus argus) depends on ants for the satisfactory completion of its life-cycle. This is described as a myrmecophilic relationship. Eggs are deposited close to the ground in areas frequented by ants, sometimes on plants that the larvae can eat, but also on bracken and under stones, where they lie until the following winter. The main larval host plants are heather, bird’s-foot trefoil and gorse, but only tender “pioneer” shoots are eaten. The young larvae are found and tended by ants of a few species within the genus Lasius. Lasius psammophilus (formerly referred to as L. alienus), nests all over the common, but particularly where vegetation is sparse and sunlight reaches the ground. L. niger is also present, but in lesser numbers. The ants are attracted to a sweet substance, which the larva secretes from a honey gland on its back. The presence of the ants protects the larvae from predators, notably parasitic wasps, and their reward is the honey. When the larvae are ready to pupate, they are accompanied underground by the ants, usually into an ants nest. They do not eat the ant grubs in the way of the Large Blue, but benefit from continued protection until they are ready to hatch. Their chances of surviving a fire on the heath are much improved whilst below ground.
The adult butterfly emerges from its chrysalis in late June, and crawls out of the nest in the company of a cluster of ants, giving it continued protection during the period of vulnerability whilst it dries its wings for flight.
Larva of P. argus attracts black ants of Genus Lasius
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