With day-time temperatures reaching 21 degrees and with a brisk southerly breeze, it has been a good week for migrant Lepidoptera. A Clouded Yellow butterfly on the last day of September was our first of the year and a colourful addition to the Red Admirals and Small Coopers that are still busy on the ivy and bramble of the island’s east coast.
Last night (1 October) we set two moth traps, my portable heath trap in the valley next to the farmhouse and our portable skinner trap out in the old arable plot in the middle of the island with acid grassland on one side and heather on the other.
After an early start for Wales’ last group match in the world cup, it was slow progress emptying two busy traps. Having evicted masses of crane flies, the egg boxes were full of moths. The most prominent species was Lunar Underwing with over 600 individuals between both traps. 17 species were recorded in total, not bad for the beginning of October.
4 species were new to the Ramsey list; The Sallow was caught in the valley next to the house, a common species taking advantage of the over-ripe blackberries and Red-line Quaker was recorded from both traps. The windy weather on the coast here often prohibits trapping in September and October which may be why these two common autumn species had not been recorded previously.
The exciting species are migrants and The Vestal is one of those. 2 individuals of this seemingly delicate moth were recorded, although when you consider that it breeds in Iberia and northern Africa and migrates into northern Europe in many years it is obviously not as fragile as it looks.
Our fourth new species last night was L-album Wainscot, again with two individuals in the heath trap. With a distinctive white L shape on the forewings this is a striking moth. Although this species breeds along the south coast of England, the moths we are seeing are likely to be immigrants, pushed up by the southerly winds from mainland Europe.