10th September

With a drizzly start to the morning, expectations had been raised for a decent fall of migrants, although such hopes were soon dashed after the first couple of empty net rounds - the day's eventual grounded migrant tally was in fact considerably poorer in both number and quality than most during the last week! As it was, most of the day's bird activity occurred overhead with 39 Yellow Wagtails, 15 Tree Pipits, 10 Siskin, 4 Grey Wagtails and singles of Cattle Egret and Osprey passing through the Bill in the morning alongside a pulse of over 150 Swallows and 50 House Martins. At sea, 49 Balearic Shearwater and just 1 Arctic Skua were recorded. 

The threat of a deluge or good storm loomed throughout the morning without ever actually materialising © Jodie Henderson

Due to the diligence of visitors to the island two nice micro-moths have come our way over the last couple of days, Last night, John Chainey, Jenny Spence and friends trapped an Echium Leaf-miner Dialectica scalariella at Freshwater Bay - a new species for both Portland and Dorset. Formerly a great rarity with just single records in Kent and Scilly, scalariella was found breeding at Dungeness last autumn; in the light of this latter discovery we'd already made half-hearted and - most likely because we're fairly inept at this sort of thing - unsuccessful searches for the leaf mines on Viper's Bugloss at various spots around the island but it wouldn't surprise us at all if last night's specimen wasn't a one-off vagrant but part of an already established breeding population:

Feathered Stem-moth Ochsenheimeria taurella is a day-flying species with rather peculiar habits - apparently it usually only flies for a short while around midday - whose presence on the island was well-known to the Victorians: Nelson Richardson - who was pretty good at not missing much - described it as 'sometimes common in fields on top of the cliff', but thereafter it escaped attention for more than a century until one landed on David Slade while he was birding near Southwell on 10th September 2006. With no further records in the intervening time we cut to this week when Graham and Zoe Geen have discovered several specimens floating in the swimming pool of their holiday accommodation at the Higher Lighthouse; whether swimming pools - or perhaps more practically trays of water placed in its grassland habitat - offer a way of recording the presence of this obscure and no doubt very under-recorded species remains to be seen! © Martin Cade: