I was walking in the countryside last Saturday morning around 8am and the weather was bright and sunny. It was also freezing and the grass was glistening with the first frost of the Autumn. Despite the temperature it was a beautiful morning, enhanced by a deep blue, cloudless, sky and a three quarter moon, and as I wandered along a hedgerow a red admiral butterfly fluttered past.
Red admiral – not the one that fluttered by on Saturday, this one is from earlier in the year.
The colours of the red admiral are gorgeous. It was only when I studied a photograph of one that I really noticed the electric blue spots at the back of the wings and lining the tip of the forewings, and I wonder if the red circle is meant to resemble a fearsome Cyclopean eye to deter potential predators. Whatever the biological rationale they look stunning against the green foliage.
The appearance of the red admiral surprised me for two reasons, firstly because it was so cold, and secondly because in my part of the world all butterfly numbers seem to have been massively reduced compared to last year.
Last year was a really good year for butterflies and in early August, on a hot summer day, myself and my daughter went to a close-by fallow field and did the Big Butterfly Count organised by Butterfly Conservation (http://butterfly-conservation.org). We counted 9 species in our 15 minute survey window, including painted ladies which migrate to the UK for the summer from as far afield as Africa.
I think intercontinental migration is an astonishing feat of endurance for any creature, but for one as delicate and ephemeral as a butterfly it’s totally awe-inspiring. The odds stacked against any individual surviving such a journey must be mightily slim!
Conversely, it was very noticeable that the weather in 2011 was alot colder (it was the coldest summer since 1993 apparently) and butterfly numbers were significantly down compared to last year, in particular the common blue:
The aptly and, this year, inaptly named common blue. This one, with his wings wide open, is a male…
Bizarrely, the female common blue is actually brown
She is looking ragged after a hard summer of mating and egg laying necessary to secure next years population. Common blues and brown argus butterflies can commonly be seen together, they are closely related and the brown argus and female common blue can be tricky to tell apart. She is distinguishable from the brown argus by her overall shape which is very similar to the male above, the white around the orange spots on the hindwing, the blue along the wingroots and the lack of a black cell spot on the forewing, all of which are not observed on the brown argus:
Brown argus sipping nectar from ragwort flowers above. And below revealing the slight differences in the spot pattern compared to the common blue female:
The brown argus can have a blue irridescent sheen when it catches sunlight at the right angle and the wing veins extend through the white wing border, which they don’t in the female common blue.
During a walk through our field at the start of August last year I would see tens of common blue, both male and female, but on the same walk at the same time this year I was lucky to see more than 2 or 3. The results from this years Big Butterfly Count corroborated my unscientific observations and it reports that common blue numbers were down by 61% in this years survey. I’m hoping we get a milder winter this year and a warmer summer next year so the numbers of these beautiful creatures can recover.
I took lots of cool butterfly pictures last year, but as it was before I started writing the Naturephile I was hoping to post them this year. But it didn’t quite come to pass so I’ll try to sneak some of them out under spurious pretexts to brighten up this winter!