Clouded Yellow breeders – Butterfly Briefs

I got a tipoff about Clouded Yellow (Colias croceus) on a lucerne/alfalfa and clover field in Aldreth a couple of days ago. Many dozens of them, apparently. I had a look a couple of days ago, but it was cloudy and windy and we only saw maybe a couple of dozen. A day later with better conditions, perhaps 50 or so (female helice form seen). But, I did a proper walk around the perimeter of the fields on 25th September (with permission from the farmer) and counted 108 as well as many dozens of Common Blue, a lot of Small White, a Hummingbird Hawk-moth and a Silver Y. A pristine female Clouded Yellow nectaring on Alfalfa (Medicago sativa) People have been reporting pockets of CYs all summer in Cambs and elsewhere. It’s been a very good year. The County Butterfly Recorder seemed a bit bored by the number of reports come late September, although was astonished by my 100+ record today. It’s not necessarily migrants arriving in an ongoing irruption. The more obvious explanation is that they’ve…