Friday, 2 August 2019

Warm weather and gulls feeding on ants at Castlemartin

During warm sunny spells in the summer, it's not uncommon to see huge numbers of ants (especially yellow meadow ants (Lasius flavus) actively swarming in the coastal grasslands on the Castlemartin Range. The current spell of warm, humid weather has triggered many to swarm this week and, as usually happens, many gulls are attracted to take advantage of the food-fest.

While out this morning with Paul Culyer of NRW checking out out marsh fritillary webs, the scene at Linney Head was quite a typical one for the time of year. Hundreds of herring gulls, quite a few lesser black-backs and smaller numbers of great black-backs were feasting on emerging ants from the numerous ant hills in the area. Gull numbers on these occasions can reach a thousand or more. Today there were probably at least 500-600 feeding in the grassland and along the Linney road - certainly many more than the local breeding population were involved.

A very small part of the gull feeding flock that was spread out between Berryslade and Linney Head
 

The ant-feeding season is usually a relatively short one however, and it could be all over in a couple of weeks or so. Some good-sized flocks of linnets and goldfinches are also starting to appear on the coast - taking advantage of numerous seeds in the herb-rich, semi-natural grassland.

Yesterday we walked the coast path from Musselwick to Little Haven. It was interesting to see choughs feeding in a couple of fields between St Brides and Borough Head, in places we're not used to seeing them. Noting Rays earlier comments about Painted Ladies, yesterday we must have seen 100's along the coast path with bumper numbers of several other butterfly species too - probably the largest numbers of butterflies we've seen in one day all summer.