large Tortoiseshells

[lazarus]

i remember reading within the past four or five years that a naturalist at either a National Trust or Natural England property in south Devon was claiming that large tortoiseshells had bred there. Does anyone have a link for this, or did I completely dream it?

Jon

[David M]

I'd be very interested to read about any evidence of breeding Large Tortoiseshells in the UK.

To my knowledge, adults have been seen in early spring on the Isle of Wight fairly regularly in recent years but I'm not aware of any reports of earlier stages (which would be proof of a breeding population).

[lazarus]

i am sure I read about it, but cannot find it anywhere

[David M]

This species is fairly easy to rear if one obtains stock from the continent so you can never rule out artificial colonisation.

[Neil Hulme]

Hi lazarus and David,

The article would almost certainly be that written by Matthew Oates of the National Trust, suggesting that circumstantial evidence for breeding on the IOW is building (which it certainly is), but we still need to find evidence of early stages to clinch the deal - which might take some time.

One very experienced observer, who lives overlooking the sea on the southern side of the island, had one fly into his garden, hibernate and then reappear the following spring. He also saw a 'probable' LT fly over his fishing boat, while just south of the island. This is just one of many lines of evidence which suggests they are (at minimum) regularly over-wintering there as migrants.

BWs, Neil

[lazarus]

i could have sworn it was the warden at either Berry Pomeroy or Dartington Court in Devon. but try as I may I can't find it.....

[Jack Harrison]

It is easy to presume that as the LT's last stronghold (late 1940s) was East Anglia, that is where it is most likely to re-colonise. There is minimal logic in that presumption.

Jack

[bugboy]

Interesting to hear of a potential recolonisation, no matter how circumstantial the evidence is. Does anyone know how the continental populations are faring, are they expanding?

[David M]

This is a tricky species to study, bugboy, as it generally occurs in low density and is usually most frequently seen in early spring (when butterfly watchers are off their guard).

I do wonder whether Dutch Elm Disease caused it's disappearance from these isles but if that were the case how come White Letter Hairstreaks are still widespread (if tricky to observe)?

[bugboy]

This is a tricky species to study, bugboy, as it generally occurs in low density and is usually most frequently seen in early spring (when butterfly watchers are off their guard).

I do wonder whether Dutch Elm Disease caused it's disappearance from these isles but if that were the case how come White Letter Hairstreaks are still widespread (if tricky to observe)?

My own theory on the Large Tortoiseshell is that it is simply part of a natural waxing and waning of it's range, the UK being on one of it's limits. It's not limited to Elm as a foodplant afterall. As to the WLH, that prefers the hardier Wych Elm Ulmus glabra which was less affected by Dutch Elm.

Most English Elms Ulmus procera are clones from a few 'doners' cultivated in the 17th and 18th centuries from suckers from a few choice trees and so were always going to be hit badly. Before then it was apparently quite a rare tree in the UK.

[dave brown]

i could have sworn it was the warden at either Berry Pomeroy or Dartington Court in Devon. but try as I may I can't find it...

You were not dreaming, unless I shared your same dream. I recall reading about that, possibly the Branscombe area (Devon). Being that no further news was put out the following year I assumed that no more were seen, or that it was deemed a release. Seems that the Isle of Wight is still the best chance.

[lazarus]

Thank you Dave, it is nice to know that I haven't lost what little remains of my mind. This is one of the big problems with the Internet. anyone can post anything, and whilst quite often things that are inaccurate do get removed, sometimes people do see them and a new 'meme' (if that is the cirrect word) enter the public consciousness.

A few years ago whilst researching for a book I was writing, for example, I came across what appeared to be a bona fide web page about the events just after the German Army surrendered in 1945, when - according to the author of this page - there was an unholy race between the British/US and the Soviet rparmies to get to the Danish border, and it was only because the British and Americans got there first that Denmark didn't join the Eastern Bloc. It was very plausible, but I have never found it again, and a Danish friend of mine who is a polymath had never heard of this.

So, Ladies and Gentlemen. Did the Large Totroiseshell breed a few years ago at a National Trust property in Devon? Someone did write about it on a webpage that has since been taken down, because both Dabe and I remember seeing it. But did the event actually happen? or will it forever be one of those half truths that litter every branch of the ntural sciences.