Thursday, March 27, 2008

The Garden Blackcap Phenomenon

The Blackcap Sylvia atricapilla is always a welcome visitor to the garden, and this photograph shows the male, which was digiscoped on 21/03/08. The male and the female differ from one another by the colour of the cap. Black in the male and rufous-brown in the female.

This species is normally migratory, visiting the UK between April and September, and wintering in Spain, Portugal and North-Western Africa. However, there are an increasing number now over-wintering in the UK, which have arrived here from Northern and Central Europe. These birds steal a march on the Iberian and African migrants by returning to their summer breeding grounds two weeks earlier, and hence getting the pick of the best breeding sites.

The Blackcap is from the warbler family and its diet is pre-dominantly insects. It is able to survive the winters here due to the increasing mild weather and its ability to change its diet to berries and other natural woodland food, and then when this runs out, moving onto food available in garden feeders. This will explain why they tend to move into gardens from late December through to March.

I have recorded this species in my garden on the following dates:
20/01/01 – female
27/01/02 – male
11/01/03 – male
07/01/04 – male
21/02/04 – 2*males
27/11/04 – male
12/01/08 – female
18/03/08 – male. Stayed until 24/03/08.

Monday, March 10, 2008

Garden Butterfly Review of 2007

This is one butterfly that I can quite confidently say will never turn up in my humble garden. It is the enigmatic Brown Hairstreak Thecla betulae. It is probably our least observed butterfly as it spends most of its life out of sight above a 'master tree', which is normally an Ash. This is another species that we have managed to almost destroy by hedgerow destruction and idiotic hedgerow management. Who ever invented the tractor-mounted mechanical flail would give the Royal family a run for their money as the champions of nature haters. This butterfly has the misfortune to lay its eggs on young twigs of Blackthorn.

As far as the garden was concerned, and despite the generally poor weather last summer, I still managed to record 12 species of butterfly for the year. This is the same number as 2004, 2005 and 2006, although the 12 species do vary from year to year. July is normally the predominate month whereby 8 or 9 species are normally recorded, however due to the dire weather, only 4 species were seen in 2007. August came out on top with 7 species, one of which was the Red Admiral Vanessa atalanta, which was the most observed butterfly throughout the year, seen in 5 of the months. As in 2006 it was the last observed butterfly of the year with the last sighting on 2nd November. The first butterfly to be seen was the Peacock Inachis io, observed on the 28th March. The record so far is held by the Brimstone Gonepteryx rhamni seen on the 18th March in 2005.

Winners last year as far as I'm concerned was the single occurrence of the Common Blue Polyommatus icarus seen on the 26th August. I have also had single occurences of this species in 2004 and 2006, but am unable to explain why! Losers were again the Small Tortoiseshell Agais urticae, as this has now not been seen since the 18th July 2004.