Wednesday 9 July 2014


'Incomers' aren't always as welcome as they might be in some parts of Purbeck, so here's one whose appearance shouldn't be controversial at all, or probably that much of a surprise given the changing climate: the Continental Swallowtail butterfly. A few sightings in previous weeks turned into regular ones at St Aldhelms Head, and it appeared that a small emergence, presumably of individuals laid as eggs by migrants some time last summer, was underway. In which case, they're not incomers at all really, but 'proper' natives now. And as British as the britannicus sub-species which is found in the fens of East Anglia.
Contintental Swallowtail, St Aldhelms Head
But not so fussy it would appear, as these were feeding on some pretty scabby clifftop thistles, lowering their standards well below that of their Norfolk cousins who rarely stray far from their reedbed colonies. I dashed off after work one warm evening last week with two children in tow, along with an essential ingredients for such a twitch: hand-held electronic gaming devices to keep them amused while I searched for Swallowtails.
The red eye on the left hind-wing can just about be seen in this shot
Remembering Steve Smith's advice that they seemed to like the cliff edge I walked a short stretch of it and found one tatty but still impressive specimen which then flew onto the short grass of the main South West Coast Path to bask. After a few minutes it dropped into clifftop vegetation, presumably to roost, and was not seen again that evening. Steve has diligently catalogued and identified individual Swallowtails from various photos taken in the area so we can be confident of the presence of at least 5 individuals.
A Windhover doing what it says on the tin at Chapman's Pool
There is some slight concern about the origins of Continental Swallowtails, as apparently some of today's newlyweds, not content with sending lanterns burning into the night sky to become tomorrow's litter, are now releasing butterflies at their summer weddings. Presumably as a symbol of the fragile, ephemeral nature of their love which will die before autumn arrives? Whatever happened to cake and confetti?
A young Peregrine cruises along the Purbeck coast
Anyway, research is apparently underway to establish whether there is any possibility of a wedding-based butterfly release in the area, so hopefully that will draw a blank to help put any doubts to bed. In the meantime, similar emergences at other southern coastal locations at around the same time certainly suggest something more 'natural' was afoot.
My sons occupy the wooden bench near which the Swallowtails could be found. Do you think they are (i) hiding to avoid the embarrassment of being associated with me and my geeky hobby (ii) keeping the sun off the screens of their Nintendo DSs? Yes, agreed: probably a bit of both. 

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