Red Admiral overwintering 2018/2019

[Vince Massimo]

This topic is being opened again in order to provide a location to collate overwintering sightings of the immature stages of the Red Admiral. Last winter produced a lot of valuable data from across the country, but the lower number of adults seen so far would indicate that there are likely to be fewer reports this time around.

Last time my primary observation site was a nettle bed in the shelter of was a south-facing cemetery wall in Crawley, Sussex. However, this season the conditions here are significantly different because, although the adjacent meadow has been mown, a wide margin has been retained and so the nettles have not been cut or had the opportunity to produce fresh growth. Whilst this may be beneficial to other wildlife, it has not produced conditions which are conducive to Red Admiral egglaying. (Edit - I actually found 6 eggs there on 6th November).

Nettle bed with eggs - 23-Nov-2017

Overgrown nettle bed - 1-Sept-2018

However whilst I was in Lancing on the Sussex coast on 21st October I found concentrations of Red Admirals feeding on Ivy or flying along the beach. Some were clearly heading south across the sea, but some also seemed to be coming in and flying north. There are several nettle beds here in the shelter of south-facing walls and fences where I have found eggs and larvae in past years. One bed of fresh growth backs onto a car wash premises which is 70m from the beach near the main car park.

Nettle bed - Lancing, Sussex 21-Oct-2018

Egglaying was observed here and at two other adjacent sites and a quick scan produced tens of eggs, mainly on nettles closest to the fence. There were also a few small larval tents.

Egglaying Red Admiral - Lancing, Sussex 21-Oct-2018

Red Admiral eggs - Lancing, Sussex 21-Oct-2018

I hope to continue to monitor their development through the winter.

Vince

[David M]

...the lower number of adults seen so far would indicate that there are likely to be fewer reports this time around.

I'm sure you're right, Vince, but this is a notable winter 'distraction' and good that it should be continued.

If far fewer reports are received, then that in itself will represent a little bit of citizen science to add to what we've seen already.

[Paul Harfield]

Last Saturday 20.10.2018 I counted 8 Red Admirals at my Red Admiral hotspot near Southwick in Hampshire. At least 2 of these were egglaying females.

[millerd]

Egg-laying female seen today (8th November) on my local patch at Stanwell Moor Middlesex.

Dave

[Nigel Cottle]

Sunday 11th November. Taunton. VC5.
Six Red Admirals found in the Bishops Hull area of Taunton today three of which were egg-laying.
In recent years I have recorded egg-laying here in every month October - March apart from January.

[Padfield]

Females laying in my garden in Woodbridge, Suffolk (images in my diary). I'll keep a track of the eggs over the coming weeks.

Guy

[Pete Eeles]

Thanks to Vince, I got the opportunity to get some shots of a coloured-up egg, as well as a larva emerging, and thought I'd share

Cheers,

- Pete

[Padfield]

Absolutely wonderful shots, Pete! The caterpillar emerging is just exceptional.

Guy

[David M]

Some great reports and information here. I hope those who have latched onto early stages at this late time of year can continue with a commentary through the winter.

[Paul Harfield]

It was suggested that I transfer this post to this topic.

27.10.2018 - This was a day that was very marginal for butterfly activity. Briefly sunny at midday but only about 6-7 degrees. I had noticed a Red Admiral active in the garden but very jittery. As soon as the temperature dropped it was seen fluttering around a spherical hanging basket filled with artificial foliage in the shade. It settled right underneath and appears to have been there ever since although its position has changed slightly.

27.10.2018 This Red Admiral seems happy in this unconventional roosting site

21.11.2018 - I have been checking the butterfly every couple of days and surprisingly it is still there . At one point I thought it had gone, but then realised the following day that it had just adjusted its position and was tucked further in. I have no idea if it has been away and come back to the same spot of course. Even on those few sunny days recently this basket is in a very cold spot out of the sun.
When I checked yesterday I was amazed to find it had been joined by a second Red Admiral
It will be very interesting to see how long these 2 butterflies remain in this situation over the winter.

21.11.2018 This 2nd Red Admiral has appeared at some point since 17.11.2018

[Padfield]

Interesting, Paul. In my experience they won't be able to make it all the way through to spring but they are well placed to test the weather and possibly fly (and reproduce) if there is a particularly warm spell in the winter months before then. In Switzerland I have found February an active month for 'hibernated' red admirals, especially if there is good weather early in the month. If the weather doesn't break until March very few come out. I look forward to seeing how yours fare.

Here's an egg I found today, poised on the tip of a nettle spicule:



Guy

[Paul Harfield]

Amazingly my 2 Red Admirals are still in situ despite both the stormy and sunny weather over the last week. I have been concerned as there has been a very prominent active spiders web attached to their home. But they are both as of today 100% alive. If I check on them in the dark with the light from my phone there is a definite reaction to the light (almost like a flinch). I am totally astonished that they are both still there.
A few days ago I thought it would be interesting to check the temperatures during the warmest part of a sunny day. On 25.11.2018 @ 1.15pm in the warmest part of the garden it was 11 degrees air temp and 14 degrees surface temp. At the roosting location of these Red Admirals it was 9 degrees. This is a fairly sheltered location out of the sun but it certainly is not dark. Although there has been a slight adjustment of position, I do not believe that they have been away and come back.

2.12.2018 Still there and 100% alive despite an active spiders web attached.

[Padfield]

Very interesting, Paul. I do hope they live to fly another day.

The eggs I saw laid on 17th Nov, as well as those I later found nearby, are still unhatched. Some seem to show some structure within but the weather has been so grim it is difficult to get photos - and they are too small for the naked eye (mine, anyway) to be terribly much use. June eggs take about 10 days to hatch. This is 15 days so far. There is no evidence any of them are dead.

The stunt egg is still in situ on the end of its spicule. I took this photo on 27th Nov - it has been too dark since, though there is no change:



Guy

[Vince Massimo]

Excellent observations and photos so far from all concerned. Thanks everyone

Additionally, I was contacted by David Harris recently who reported Red Admiral egg laying in Newhaven, Sussex on 17th and 18th November.

Vince

[Nigel Cottle]

Taunton VC5. I watched the same ragged female egg-laying on both November 29th and 30th. I am monitoring these eggs and will report again in due course.

[Padfield]

Update:

Some eggs unlocatable now, quite probably due to the heavy rain and winds trashing the nettle beds and plenty of other creatures eating the leaves. Of those I can find, all are still unhatched except one. There is no sign of a caterpillar near this egg and the open end looks very uneven so I suspect it has been predated rather than naturally hatched:



Stunt egg is still in place:



Others are on their leaves unchanged:



Guy

[Vince Massimo]

Thanks Guy,

That looks like a cleanly hatched egg to me, so hopefully the larva should be either under a leaf or in the crown of the plant.

Vince

[Padfield]

I hope you're right, Vince. I did look under the leaves but not in the crown of the plant. That's for tomorrow now!

Guy

[Paul Harfield]

As of yesterday the two Red Admirals roosting amongst plastic flowers in my garden are down to one. There were still two on Thursday when I last checked. Friday and Saturday were both quite mild and sunny days here so I guess one was woken from its roost and has flown unseen by me. I had noticed that over the last couple of weeks that one had its antennae clenched and one did not. It is the one that did not have its antennae clenched that has gone. As far as I can tell the remaining one looks healthy.

23.12.2018 One remaining Red Admiral roosting amongst plastic flowers

[Paul Harfield]

Southwick, Hampshire 28.12.2018 - Yesterday I visited my Red Admiral hotspot at Southwick in the hope I might catch a Red Admiral awoken by mild and sunny conditions. It obviously was not quite mild enough for Red Admirals to be flying as I saw none. However, a quick look at the Nettles along the front of the wall revealed at least 10 Red Admiral larval tents. These all looked like 1st or 2nd instar to me and were all in the same approximate position as last winter. I could find no eggs. The environment generally seems to be in a slightly different state to last year as there is more old dead vegetation still in situ. I guess any cutting that has been done has been done at a slightly different time.

Not a great photo but if you zoom in a 1st instar larva can just be seen centre frame.

This was the largest of the tents I found and was the only one I opened. 2nd? instar contents shown below