Monday 19th.April 2010

I managed to time my time out today , as so often happens , just as the cloud cover came over and the sun disappeared . My first stop was at Salt Box Hill , just below Biggin Hill Airport , a SSSI managed by the London Wildlife Trust . On my last visit last year , fencing had been erected with gates to gain access . Today , those gates were padlocked , with notices stating that Dartmoor Ponies had been put on the site , to eat the long rank grasses . I could only find two ponies , and they are going to have to work really hard to make an impression , but would have thought that they would be removed soon , or they will start to feast on the Chalkland plants and especially the Orchids that grow there . There has also been a lot more clearance of large trees and scrub , worrying as this sight was very good for Brimstone butterflies over the last couple of years , and the clearance seems to have included most of the Buckthorn , which is it's food plant . Hopefully , the clearance will not affect the Marbled White population , which is spectacular on the site . Whilst there , I only saw one Brimstone and one Peacock , from outside the fence . The highlight was a pair of Sparrowhawks sparring/playing on the edge of the woodland , but never clear enough to get a shot .
Having recorded Green Hairstreak , I thought I would check out Burnt Gorse at High Elms , a good spot usually to see them . But , when I got there , the sun was still behind cloud , and a cool breeze was blowing down the slope . At the bottom , where it was a bit more sheltered , I did find what I thought at first was the Marmalade Hoverfly , but realised when I got home that it wasn't . After a bit of digging , I think it is Parasyrphus punctulatus . Also found on site , was this all black Bumblebee , but I need to do a bit more research on this one . The most numerous species seen , and hear , was the Bee-fly-Bombylius major . They were everywhere , and I even saw a pair mating on the wing , like other insects , abdomen to abdomen , but by the time I got them focused , they had parted . I've mentioned the long proboscis before , but this one on alight coloured leaf , shows that they also have long legs . No Green Hairstreaks were seen , in fact I only recorded a few Peacocks , mostly trying to keep warm on bare paths .
Heading back to the car , I found the first specimens of Toothwort on the side of a path . These plants are members of the Broomrape family , and are parasitic on their host , often Hazel , but on other trees too . They contain no green pigment , and as all it's nourishment comes from the host , it has no need of chlorophyl . A bit further along , Green Alkanet , a member of the Borage family has come into flower since my last visit .
The expected birds were seen/heard , but nothing more than that . On the way home , I noticed that the Rookery has increased by one nest , to nine , and the single Swallow that I posted , now has two others with it , hawking for flies over the stables .