2016 for butterflies
The recent cold weather may make this seem an odd time to be thinking about butterflies. However, it’s also the time when Wharfedale Naturalists have to sift through their records – and memories – to send data to our Recorders who then have the mammoth task of correlating these and writing up a report for our annual journal.
I knew it had been a poor butterfly year, but just how poor has been born in upon me as I look back at my summer notes. Usually I have two exciting times for spotting butterflies in the garden. It can start as early as February if we get a few warm sunny days, and, as the season advances, more of the overwintering species emerge from hibernation and start the serious business of finding a mate and laying eggs to provide the next generation. 2015 was a good year for butterflies – indeed, it seemed that one of our commonest garden butterflies, the small tortoiseshell, was recovering from the devastating effects of disease – their numbers in late summer were definitely up. So I was expecting great things in the early part of 2016.
Alas, I only saw a couple of Peacock in April, one small tortoiseshell near Middleton and a couple of orange tips and another peacock in the garden in May. The summer months produced only small whites, and not many of those. Even the large or cabbage white was scarce. As for the late summer – a couple of tired looking speckled woods and a solitary painted lady, though I understand that the usual influx of the latter had occurred down south.
Though our recorders have not yet completed their work, my experience seems to mirror that of Wharfedale as a whole. Last year we received records for 521 butterflies, this year only 58. The Butterfly Conservation’s Big Butterfly Count in July-August has yielded similarly dismal results for some of our favourites – peacock and small tortoiseshell sightings were down by 40%. There was some good news – Red Admirals – another migratory species – is up 70% though I wouldn’t have guessed that from my garden.
The reasons for this general decline are still being debated. The mild very wet winter may have disrupted hibernation patterns and a long cold spell have killed off early emergers or their food plants. Disease or harmful pesticides may have contributed. Whatever the causes, insects are sensitive indicators of climate change and environmental health. We need to take these statistics seriously.