Tuesday, 10 June 2008

Castle Hill Small Tortoiseshells

Castle Hill looms over Folkestone, looking across the sea to France (although it was the French Normans who last used it, to subdue the Anglo-Saxons after the Conquest).
Now, the road to Dover and to Europe skirts the foot of the hill.
There was a surprising abundance of orchids on Castle Hill when I visited - Common Spotted on the northern slopes and on the top,
and hundreds of Fragrant Orchids on the southern faces. The scent of the Fragrants is so lovely, that the visitor is tempted to his knees to enjoy it all the better.

I saw a Painted Lady butterfly resting on a stem, with another settling nearby, then flying off to chase away invaders. The chaser looked battered and worn, unsurprising after its migration from southern Europe or northern Africa.
The targets of its aggression included other Painted Ladies, a Red Admiral, and was that a Small Tortoiseshell? It was!
A couple of years ago we wouldn't have given this common butterfly a second glance, but they have undergone a serious decline so that such a sighting is now rare. There were two here, right on the top of the hill on a patch of nettles.
There has been much discussion on the possible reasons for the decline, and one of the most intelligent contributions was this one from Steve Nunn, the New Hythe man:

Like everyone else I have struggled to see Small Tortoiseshell in the last couple of years. According to Butterfly Conservation populations have fallen by over 80 per cent in the South East.
The suggestion is the cause is Sturmia bella , a tiny fly first seen over here in 1998. The fly, common on the European mainland, is thought to have become established due to climate change. Sturmia bella eggs are increasingly found on nettles the foodplant of Small tortoiseshell caterpillars. It is thought that Small Tortoiseshell caterpillars eat the eggs which then hatch and kill them.
There is a current research project being jointly carried out by Butterfly Conservation charity and Oxford University's Department of Zoology to determine how significant the parasites are to Small Tortoiseshell decline. I suggest that any sightings of Small Tortoiseshell (or any other Butterflies!) are reported via the kent butterflies web site - even records of the most common species are useful as the plight of the once common Small Tortoiseshell just shows us how quickly things can change. The web site is www.kentbutterflies.org


I also saw my first Skipper of the season.



8 comments:

Mary said...

Beautiful place to walk! You always have such a nice mixture of British history and nature facts :-) Great that you saw two of the Tortoiseshells! The other butterflies are lovely, too. You see a lot of different kinds. The pictures are very detailed!

Warren Baker said...

Nice Butterfly shots steve. especially like the Common Blue.

Simon said...

Nice post Steve. Great shots of the butterflies - pleased to read that you've seen Small Tortoiseshell.

Anonymous said...

Enjoyed reading your blogg and glad you found Small Tortoishells -they are indeed a rarity these days .
But your Essex/Little Skipper is in fact a Large . The mottled /
chequered pattern on the wings identifies it and the dark line -
sex brand - on forewing denotes a male .
Not as easy , but I think your female Common Blue is in fact a male Brown Argus , but I wouldn't put my life's savings on it from this distance !!
Greenie

Kingsdowner said...

Thanks for the comments!

Greenie, thanks for the ID of the skipper - I'd thought to myself that the Essex/Small was a little early, but it's about right for a Large.
They aren't very large of course, and I'd forgotten to check the chunkiness of the thorax.

As for the Blue, I'd be pleased to accept an ID of Brown Argus, based on the dark spots on the wings.
How much I forget from one summer to the next. I give up!

John Young said...

Hi there. The meadows at Jeskyns are fairly easy to find. Park in the car park and take the pathway that runs west parallel with the road. You'll pass a house on your right with some alpacas in a small field and come to a crossways in the paths. If you turn right and start walking toward the road you'll see the meadow with the cornflowers on the opposite side of the road. The meadow with all the ox-eye daisies is in the opposite corner so retrace you steps to the crossways and then go straight ahead. Look for two statues of people and you should start to see the dasies in the distance.

Sandpiper said...

A wonderful post, as always! I really enjoy seeing the scenery there.

me ann my camera said...

Wonderful butterfly finds and I am surprised to see a few familar ones as well as a skipper. All very nice. Butterflies and wildflowers are often the focus of my days recently too.