Chalkhill Blues

[David M]

How long is their flight period?

I ask because I first went to a CHB site on 19 July and saw 4 freshly emerged specimens. I've been back today, a full 6 weeks later, and not only are there dozens of them about, a healthy number look immaculate as if they're not long out of the pupa.

[millerd]

At Denbies Hillside in Surrey, the first males I saw were flying on 3rd July. Visiting last week (22nd September) I saw one fairly fresh male probably only a few days old. The whole emergence must have covered 11 to 12 weeks by those dates.

Dave

[Crispin]

Gosh! That is late for CH Blue. My, personal, latest record for Chalkhill in 2010 was 4 Sept, prior to that it was the 17th Sept in 1996 (transect data) but I would not be surprised if there was something a bit later if I searched through all my and my fathers records and other records.

I would expect their emergence is staggered.
Not sure how long an adult lives for but I would expect about two weeks at best - depending on conditions.
So, if your sightings

look immaculate as if they're not long out of the pupa

then I think you could be seeing some very late CH Blue.
Were they male or female or a mix?

Crispin

[NickB]

Hi
CHBs seem to have moved forwards in their emergence over the last few years. It was seen as an August butterfly; it is now at its peak in mid-July, as often as not, on our sites in Cambs. BC Branch records for 2009 show a wide emergence period and sightings from 21st June <-> 12th Sept; this year, the first sighting was on 5th July and last so far 1st Sept.....
I am sure there are specimens hanging-on until well into September on most sites.
N

[Gruditch]

Agreed.

My first Chalkhill this year was on the 25th June, unfortunately I don't think this lone males plan of "early bird gets the worm", worked out. As it was another 4 weeks before the first females emerged. We were still recording 20+ Chalkhills on the 9th September, including some good condition males.


Regards Gruditch

[NickB]

I remembered this thread following my trip to Burwell Cutting on 2nd October, where I saw a single aged Chalkhill Blue female...

..any advance on 2nd Oct?