www.ukbutterflies.co.uk

Today Matthew Oates had a stupidly late sighting of a fresh Ringlet at the BC reserve at Magdalen Hill Down in Hampshire. Late emergence or 2nd brood?

Cheers,

- Pete

Were the first ringlets of the season stupidly early?

Guy

The earliest Hants sighting was 29th May - so a couple of weeks early.

From Matthew: "Definitely 2nd brood - a very fresh male. Richard Fox says there are 2nd brood records for South Devon in 1986".

Cheers,

- Pete

I was going to say the same. If the butterfly emerged early this year there is a high probability late sightings are a partial second generation.

Guy

Indeed. I find it fascinating that some species are able to "throw out" a 2nd brood if conditions are favourable and clearly respond to temperature rather than photoperiod. Others, it would seem, definitely need a good old diapause as part of their lifecycle.

So do Ringlets regularly produce 2nd broods on the continent?

Cheers,

- Pete

I wonder what the evolutionary advantage of a small second brood might be? If only a few butterflies emerge, the chance of finding a mate is reduced compared to emerging at the normal time. If mating does occur, the larvae will be smaller when they overwinter - is this a good thing or not?

Cheers
John W

I can't see any advantage. I think of it as a false start.

This is perhaps the most bizarre sighting I've ever heard of in this country. Could it perhaps be down to something artificial like the original egg being laid in a greenhouse?

Not so bizarre when you consider the late heat wave that we had.

I am sure that breeders have been able to artificially shock butterflies into emerging early by creating certain conditions. I would imagine that once a caterpillar reaches a certain size all that would be necessary would be a certain time below a specific temperature followed by a certain time above a temperature to achieve the required result. So, an egg which was laid early in the season followed by the cool summer and hot autumn would do the trick nicely.

I've never seen or even heard of second brood ringlet, I must admit.

I believe creativity is born of the ability to make mistakes - to capitalise on accident - and there is nothing more creative than Nature! Ringlets are single-brooded but the (usually) latent possibility of individuals accelerating their development and flying in the autumn is surely part of that built-in flexibility and adaptability that enables species to respond to environmental changes and climatic shifts. The green hairstreak I photographed last October was a mistake and maybe Matthew Oates's ringlet will live an unfruitful life too (or maybe not). But the possibility of these things happening is probably quite important to the long-term survival of species in a changing world.

Guy

Is it down to the recent heatwave though? I read in the news a couple of days ago that rare migratory moths were being sighted in record numbers in the south of England yet there doesn't appear to have been a similar influx of butterflies.

Maybe it's a combination of the hot weather in late March through April and the blast of mediterranean air towards the end of September, though I have to say that throughout it all, butterfly numbers in my part of Wales were disappointing.

padfield wrote:Ringlets are single-brooded

I bet no one thought to tell them that.

David M wrote:Is it down to the recent heatwave though? I read in the news a couple of days ago that rare migratory moths were being sighted in record numbers in the south of England yet there doesn't appear to have been a similar influx of butterflies.

Maybe it's a combination of the hot weather in late March through April and the blast of mediterranean air towards the end of September, though I have to say that throughout it all, butterfly numbers in my part of Wales were disappointing.

I think you're mixing two separate things here. One is with regard to temperature and its affects on the individuals already present (i.e. the Ringlet observation). The other is with regard to migration.

With respect to the latter, influxes of migrant butterflies (as far as I'm aware) are reliant on a buildup of individuals on the continent (typically) as in the case of Large White, Red Admiral, Painted Lady, Clouded Yellow etc. But since their flight period may well be coming to an end (on the continent) then this hasn't happened. I can only assume that the influx of migrant moths is because they operate on a different cycle and are present in good numbers such that the right weather conditions brings them over.

Cheers,

- Pete

Thanks, Pete.

Regarding the migratory moths though, surely if moth numbers on the continent are unusually high due to excellent weather, then butterfly numbers ought to be high too - or am I being overly simplistic?