Tuesday, August 3, 2010

Comma in a Cornfield

I found this comma sunning itself on the edge of a field of ripening wheat yesterday. It's a common enough butterfly now in Durham but twenty years ago it was still a rare sight here. As recently as 1986 T.C.Dunn and J.D. Parrack wrote in their Moths and Butterflies of Northumberland and Durham that occasional specimens that were reported were "...only strays and cannot yet be thought of as recolonising the north-east, although there is recent evidence of some range expansion in the Midlands. They are, however, an indication that they do arrive here sometimes and if the wandering habit were to become more frequent as during a time of expansion, it could take up residence here once more". The authors would be delighted, I sure, to know that their predictions proved to be spot-on. The species went into a decline nationally in the late nineteenth and early twentieth century, when it was restricted to the Welsh Borders and South East England, but over the last few decades it's undergone a rapid range expansion. No one seems certain why this has come about, although there are suspicions that this is now a different race of butterfly than that which was common 200 years ago, with caterpillars that now feed on nettles rather than the much less common hops. Climate change might have asisted its northwards range expansion too.

This specimen looks like an example of the paler form from the first, July, brood known as form hutchinsonii, which will mate and produce a second brood in late August. The larger, darker form in the July brood merely feeds without mating and enters hibernation along with the second brood hutchinsonii progeny.

12 comments:

  1. Thank you for this, Phil. Made all the more interesting for me as it coincides with me photographing Comma in my garden yesterday (dark form). Keep up the good work - your blog has become a regular read for me!! Thank you again!

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  2. Unusual butterfly with an unusual name.

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  3. I've never seen the Comma Butterfly over here in North East Lancs. around our area Burnley Nelson and Colne. The nearest location to our area where I've seen it was in the nature reserve in Catterick Army Camp between Wensleydale and Swaledale.

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  4. I 'twitched' my first Comma at Widdrington in the 90's. Other species that are common in Northumberland now were an amazing sight when I first saw them...Wall Brown in 1982, Peacock in 1992, Small skipper in 2005 and Speckled wood in 2007. My first Observer butterfly book had none of these species North of South Yorkshire.

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  5. Thanks Richard, it's a lovely butterfly. Buddleia is just coming into flower in my garden and I'm hoping that it will attract a few commas...

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  6. Hi lotusleaf, the last picture at http://cabinetofcuriosities-greenfingers.blogspot.com/2010/07/ripon-canal.html of the underside of the wing, shows where the name comes from

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  7. Hi David, I get the impression that, where the butterfly recolonises, it forms quite local colonies. There are places around here where I expect to see it and others that have all the right habitat factors where I never find it...

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  8. Hi Nigel, I find it really encouraging that all these species have come back and are now quite common. Ringlets used to be scarce around here but this year they've been visiting my garden. Orange tips used to be scarce here when I first came to the north east in the 1970s.

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  9. An unmistakeable butterfly. And a beauty too, with those 'ragged' wings.

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  10. Great photo Phil. I rarely see these until the second brood so there should be some about here before too long.

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  11. Hi Keith, my buddleia is in flower now and I'm hoping some will visit that..

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  12. I know what you mean John, the emerging spring commas seem to be fairly short-lived. I sometimes see them on goat willow catkins.

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