It has been known for some time now that the Brown Hairstreak are gradually spreading east from Worcestershire into Warwickshire. Unfortunately, the expansion isn't expanding as fast as we'd like it to. The county boundary runs along a busy road and is bordered by dense woodland and built up areas in parts. Last season, we found quite a few eggs close to the border in Worcestershire but only a few actually inside Warwickshire. Our main breakthrough was finding 19 eggs just inside Warwickshire near a place called Cookhill. However, i estimate around 8397589178975894 deer are in residence there and much of the blackthorn with eggs on was browsed. Visits to some promising looking ash trees during the flight period unfortunately yielded no sightings what so ever but we all know how elusive those Brownies are! I continue to live in hope.
After reports of a female Brown Hairstreak being seen in a brand new area, very close to the Warwickshire border in Redditch on 11th September, i met up with Simon Primrose on Wednesday to scout out potential blackthorn locations for winter egg searching. We decided to start at Dagtail End where we found over 20 eggs last year, the closest of which was about 200 metres from Warwickshire. Unfortunately, this area was flailed earlier in the year and so we didnt hold out much hope of finding anything there this winter. However, on our preliminary search on 26th (in the rain!), we found an excellent area of suckers with 7 eggs, including a triple! This was just a scouting trip so we will search this blackthorn more thoroughly when the leaves have fallen. This time, the closest egg was just 12 metres from the Warwickshire border! These females clearly enjoy teasing us. Further searching into Warwickshire gave us squat, including very little blackthorn which seems to be the norm these days. Along most of the key area, the excellent blackthorn in Worcestershire seems to stop as soon as the county boundary is reached and then doesn't start again until at least 250-300m into Warwickshire. How infuriating! Perhaps a mass blackthorn planting regime is in order.
Simon also found another 3 eggs a few days ago on a brief search close to the previously mentioned adult female sighting. Again, these are close to the border but i believe the nearby woodland could be acting as a rather nasty barrier for spread into Warwickshire.
The 2012/2013 preliminary egg searching has clearly got off to a good start here in the Midlands, with eggs also found at Grafton Wood.
THE AIM FOR THIS WINTER: to top last years 26 Warwickshire eggs found along the border!