5th July

Another blistering day on the idyllic Isle of Portland. Although the list of species left a lot to be desired there were signs of autumn at the obs with the first returning juvenile Garden Warbler trapped, the lingering male Serin and a new female Blackcap. The sea provided the second Yellow-legged Gull of the season as well as a smattering of the usual suspects.

A Large Tortoiseshell was again in Tout Quarry. The first Splendid Brocade of the year (at the Grove) was the best of the night's immigrant moths.

Today's somewhat out of season juvenile arrival was this Garden Warbler trapped at the Obs; Garden Warbler doesn't breed with any regularity at Portland - in fact the only records are of single pairs at West Weare in 1971 and 1972 - and as far as we know isn't at all numerous anywhere in south Dorset but, whilst clearly not as young as the Black Redstart we mentioned yesterday, this bird was a good fortnight to three weeks earlier than we'd usually expect the first autumn migrant to arrive. Kevin Shepherd's been in touch to relate his experiences at other migrant hotspots of juveniles of a range of other species turning up well away from breeding sites and it seems that surprisingly long distance dispersal isn't that unusual. It'd be interesting to discover with something like this Garden Warbler whether the post-juvenile dispersal and the long-distance migration phases of its first few months actually merge together and it doesn't really ever stop drifting off gradually southward © Martin Cade