Do Painted Lady's return to the same sites on their return?

[selbypaul]

Hi there everyone
My Uncle from Chester has just called me to say he has seen the same Painted Lady he saw 5 weeks ago in his garden. He says that he could identify it was the same one because it had exactly the same malformation on its wing. Despite the malformation, it is still a strong flier by the way.

So my question is whether:
a) It's just a fluke, and it could be a different butterfly with an identical deformation;
b) It is the same one from late July, which has probably hung around in roughly the same location this last 5 weeks;
c) It is the same one from late July, which travelled North, and has now travelled back south to the same spot.

I thought that Painted Lady's were always pushing north until late August/early September when they returned south, in which case I'd have guessed at answer c). If so, does anyone know of any capture/re-capture studies that show Painted Lady's being faithful to the same sites on their return journey's south?

However I may be completely wrong and happy to be told that by late July, Painted Lady's will have stopped their northward journey?

Any thoughts anyone?
Paul

[Gruditch]

Hi Paul

In 2009 ( the last big Painted lady year ) I had the same individual's hanging around in a garden for weeks. I also did the Danebury Hill transect at the time.

On the transect I had 1 PL in week 8, then on the big influx day ( week 9 ) I had 110. Over the next few weeks the numbers were 9, 5, 3, 2, 3. These individuals were getting tattier by the day. Its now pretty obvious that they were living out their retirement, and would pop their clogs there. On week 15, the second week in July, I recorded 23 PL, virtually all of them shiny new ones. The numbers over the next few weeks were 100, 85, 124, 150, then on the August 13th, just 28. Obviously there had been a big unified return flight. The vertical radar report that BC presented at that years AGM confirmed this. Over the remaining few transect weeks, I recorded 15, 13, 5, 0, 0, then on the last transect week, just one lonely PL.

The reasons why some individuals decided not to go with the main migration, one can only guess. Maybe they were not fuelled up enough, maybe they had already flown from further north, and been forced to stop off. If I recall, the BC report said they the radar recorded PL's flying to altitude but then returning to the ground on several occasions, before they finally made the mass migration South. The conclusion was that the conditions were not right. For some that missed the mass migration, the conditions may never have be right, so they were stuck here, and would have perish.

Questions A/B. I would say as long as there is a good food source, there is no reason why a PL will not hang around for 5 weeks.

Question c. I don't think the UK born brood from late July, would travel north. Their job is to fuel up, if that means staying the same spot for 5 weeks, so be it, then migrate south in August/September.


Regards Gruditch

[selbypaul]

That's really helpful Gruditch. Really appreciate the evidence based info.
Paul

[Padfield]

The adaptive significance of the return migration is that fertile individuals, bred in the north, return to breed themselves in the south. Once a female has laid I don't think she can reproduce again - though judging by their behaviour the males continue to believe themselves virile right up to the end of their days. I have no evidence to support this, but it would seem natural for the migration instinct to be strongest in pre-breeding individuals and for post-reproductive females in particular to chill out, having achieved their lives' goal.

Guy

[False Apollo]

To be honest I have never been truly sold on the notion that we now know everything about Painted Lady migration. That is not to say I do not believe evidence of a southerly autumn migration, but I think there other factors to consider. I believe Painted Ladies have been recorded in the UK in most months. Early March sightings are very interesting, especially inland.
The most interesting occurrence I can remember was in 1987/88. There was a winter influx along the south coast from 22 December through to 7 January. I saw one at Cowards Marsh, Christchurch, but they were seen from Farlington, Hants, to Weymouth, Dorset. This influx even made the national press. The final sighting I know of was in Pinnock Wood in the New Forest. Clearly conditions were good for a northerly movement in late December. They did hang around the areas they were seen.
I have seen an early spring faded individual inland (New Forest), not during a known influx, and often wondered about it's origins.

Regards
Mike

[Chris Jackson]

Monday 14th September 2015
South of France (Vitrolles, Bouches du Rhone) 25°C

Hi Folks,
Here is some feedback on this topic from the South of France.
Its true that I see Painted Ladies passing through my local patch early in the season, then again later in the season, presumably heading north, then heading south.
Today out of the 15 species that I counted, still flying down here on my local lunchtime patch, all of a sudden the Painted Lady forms the largest population, about 10 times more than any of the other species.
They were all in different states of wear. Here is a good cross section:

Are photo Nos. 2 and 3 both females? If they are all flying south, it would appear then that both older and fresher females follow the migratory movement.
Cheers, Chris