16th July

The mothing was considerably more interesting than the birding on a lovely warm, sunny day with the chief highlight being the discovery of an Orange-tailed Clearwing - a new species for Portland - at Inmosthay Quarry. Overnight trapping had come up with few immigrants - 17 Diamond-back Moth, 2 Rusty-dot Pearl and a Dark Sword Grass made up the Obs total - but there were signs of some dispersal from the mainland, including 3 Cream-bordered Green, 2 Elephant Hawk-moth, a Wood Carpet and a Barred Red at the Obs. By day, single Clouded Yellows were at the Bill and Ferrybridge.

Bird interest consisted of little more than singles of Little Ringed Plover and Reed Warbler at the Bill and 5 Sanderling at Ferrybridge.

Orange-tailed Clearwing - Inmosthay Quarry, 16th July 2016 © Martin Cade

With the larval foodplant - Wayfaring Tree - so common in places we'd always thought it odd that this species was unrecorded from Portland, but repeated searches had drawn a blank so it seemed like the species really was absent. Thanks to Robert Payne and his pheromone lures there is now this fully confirmed record and it'll be interesting to see if some other off the beaten track spots like Inmosthay also harbour populations.