www.ukbutterflies.co.uk

Now that the Brown Hairstreak season is upon us I am wondering if there is a preferred time during the day to see it low down feeding or females egg-laying. I have never knowingly seen a Brownie low enough for a photo opportunity. Curiously, some text books state that the best time to see them fly is between 10am and 4pm and temperatures above 20c but I have read some reports of sightings at about 7am

Peter

Hi Peter,

It all depends on whether you are after males or females - they behave very differently! Males are highly active around 'master' ash tree canopies, or make looping sorties out over blackthorn hedges, from early to late morning, particularly between 8 am and 11 am. They can then become almost invisible until late afternoon/early evening. On many sites the males rarely come down, but Shipton Bellinger is a notable exception - they fall freely here!

Females are mainly active between 11.15 am and 2.00 pm. >90% of my first (of the day) low level female records are between 11.15 am and 11.45 am. Of course there will always be exceptions, but these patterns hold true in the vast majority of cases, based >1000 observations.

BWs, Neil

Thank you very much Neil - that helps a lot. Of course the weather conditions probably play a part too but at least there will hopefully be fewer fruitless hours searching for it this year

Regards

Peter

I asked Neil this question myself about 3 years back and have found his advice to be very accurate. I've seen the bulk of my egg-laying females between 11.30am and 2pm. They seem to disappear after then.

Don't read too much into weather conditions/temperature though. At the Pembrokeshire site I've seen females active in bright conditions and 13 degrees. I also saw one last year when it was overcast and no more than 15c (beginning of October, I think).

OK - thanks David.

Where I go searching there are dozens of rows of blackthorn but none strictly facing south (as far as I know ) so would females generally prefer to lay eggs on blackthorn thickets facing east rather than west?

Peter

Hi Peter,
There appears to be a preference for south, followed by east, but west and north facing are also used occasionally.
BWs, Neil

I have been to Shipton Bellinger today and had 3 male and one female Brown Hairstreaks down in cloudy overcast conditions, from around 13.00 to around 16.00, all very approachable. For the record my latest time to see one down was 20.00 at Noarhill on a warm balmy summer evening, a number of years ago.

Regards
Mike

Thank you, Neil. I was hoping you would say 'never' rather than 'occasionally' but I understand the reasoning.

HI Mike - good to know and encouraging.

Peter