www.ukbutterflies.co.uk

Paul Wetton:

Any thoughts?

A parallel argument exists not so much about genetic differences but behavioural differences (which of course might be genetic in origin). I am thinking of the possible natural immigration of continental Swallowtails eventually interbreeding with our Broadland population. Our "new-native" Swallowtails in the future would undoubtedly behave differently.

I could - at risk of being non-PC - draw an analogy to human immigration into this country. Our customs are slowly (and in some case not all that slowly) changing. I have read that Chicken tikka masala is now considered by some any to be the British National Dish:

An expert on street food declared that the dish originated in Punjab during the last 50 years. Another view is that it originated in the first Indian restaurants in Soho during the 1970's

Whatever the truth, the so-called "national dish" is clearly a consequence of immigration; our human habits have changed.

Jack

I think personally that natural immigration is fine. If it is going to happen, then that's the natural way of things, such as the example of Swallowtails. It may even be that an influx of the european vagrants is necessary to ensure the diversity of the genetic make up of the British Swallowtails.
My problem is with human aided immigration causing disruption.
I would like to hear a reasoned argument for introducing an unatural gene pool i.e. foreign genes to an already healthy population with sufficient individuals or populations to exist. It is completely unnecessary.
As I said previously it may be required to prevent an extinction event and then I think human aided immigration (as we are calling it) may be unavoidable.

Maybe we should form the BBNP = British Butterfly National Party.

Jack

Paul Wetton wrote:I think personally that natural immigration is fine. If it is going to happen, then that's the natural way of things, such as the example of Swallowtails. It may even be that an influx of the european vagrants is necessary to ensure the diversity of the genetic make up of the British Swallowtails.
My problem is with human aided immigration causing disruption.
I would like to hear a reasoned argument for introducing an unatural gene pool i.e. foreign genes to an already healthy population with sufficient individuals or populations to exist. It is completely unnecessary.
As I said previously it may be required to prevent an extinction event and then I think human aided immigration (as we are calling it) may be unavoidable.

Briish Swallowtails are fine genetically. The general rull of thunm that is used for this is that a populations should not fall below 50 in the short term and 500 in the long term. There are thousands of British Swallowtails so there is no problem.

There probably has been some genetic interchange in the past. There are quite a few records of Swallowtails from odd locations in the middle of the 19th Century. Like for example Penclawdd and Loughor in South Wales. My ancestors lived in the former village and I'd like to think that some of them saw them. These would have had to have been continental forms
as the British ssp's habitat was not present and there certainly is no Peucedanum palustre there.

When the British swallowtail was more widespread there would have been at least some chance of genetic interchange.

Hi Neil

Some interesting information there. This just backs up my argument in that the genetic mingling you refer to would have been perfectly natural and wholly acceptable.

The Swallowtail was just an example of a possibility that was brought up by Jack.

My worry is where the gene pool of a very small population of native butterflies may be adversely affected by the introduction of a different race of individuals. This is all theoretical and I guess that a large influx of genetic material may be required to totally overwrite that which is already present.

Talking of swallowtails - one local reserve lost all caterpillars accessable from the boardwalk one evening this year. Breeders claim that their swallowtails have been captive-bred since before the law protecting the swallowtail came into force. That's why they are allowed to sell the larvae and pinned specimens on ebay. That legitimate market is quite lucrative - pinned uk swallowtails go for £35 a time at the moment. Were the caterpillers stolen for sale or to replenish the genetic diversity of some breeders stock I wonder? Either way the existence of breeders selling specimens allows the poaching of butterflies from reserves in the same way as a legitimate trade in ivory provides cover for poachers in africa.

I have read that Chicken tikka masala is now considered by some any to be the British National Dish

Jack
Last year a delightful teenage girl working for my wife was booking her two week holiday.
She was going to Scarborough.
I asked why she didn't go abroad for some certain sun.
"Oh" she said "My boyfriend wouldn't like that - he can't stand foreign food!"
"What does he like then?" I asked.
"Oh, you know" she said "Pizza, curry, KFC"
"I see" I said "he certainly won't like the muck they serve up abroad then!"
Quite sweet really.

Rogerdodge wrote:...She was going to Scarborough.
I asked why she didn't go abroad for some certain sun.
....

I can think of nowhere better to spend 2 weeks, than on the Yorkshire Riviera, in Scarborough...
(unless perhaps it is Bridlington )

HarassedDad:

That legitimate market is quite lucrative - pinned uk swallowtails go for £35 a time at the moment. Were the caterpillers stolen for sale or to replenish the genetic diversity of some breeders stock I wonder?

Hmm.

Neil Hulme come across collectors of adults of a rare species at a private site in Sussex - he chased them off. I had naively thought that very few people nowadays collect adult butterflies as voucher specimens ("the stamp collectors"). Your thoughts about keeping captive stock healthy by bringing in new blood from time to time is probably a better explanation of the occasional examples of collecting.

Jack

HarassedDad wrote:Talking of swallowtails - one local reserve lost all caterpillars accessable from the boardwalk one evening this year. Breeders claim that their swallowtails have been captive-bred since before the law protecting the swallowtail came into force. That's why they are allowed to sell the larvae and pinned specimens on ebay. That legitimate market is quite lucrative - pinned uk swallowtails go for £35 a time at the moment. Were the caterpillers stolen for sale or to replenish the genetic diversity of some breeders stock I wonder? Either way the existence of breeders selling specimens allows the poaching of butterflies from reserves in the same way as a legitimate trade in ivory provides cover for poachers in africa.

Wow - I don't think I've ever seen so many assumptions in a single post

1. "Breeders" are responsible for the loss of the larvae (not some individual who just wanted to breed them and release them).

2. "The existence of breeders selling specimens allows the poaching of butterflies from reserves". Well - that's just not true, is it?

Cheers,

- Pete

Paul Wetton wrote:Hi Neil

Some interesting information there. This just backs up my argument in that the genetic mingling you refer to would have been perfectly natural and wholly acceptable.

The Swallowtail was just an example of a possibility that was brought up by Jack.

My worry is where the gene pool of a very small population of native butterflies may be adversely affected by the introduction of a different race of individuals. This is all theoretical and I guess that a large influx of genetic material may be required to totally overwrite that which is already present.

The problem is it is not as simple as that. Take the Swallowtails that used to exist at Wicken Fen until the 1950s.
They had been isolated for about 100 years or more and eventually succumbed to changes in the habitat caused by the fen drying out a bit. They were measurably different from Norfolk Swallowtails and had changed over time. Their thoraxes were smaller and this is probably due to negative selection for vigorous dispersing flight.
So that population may have been more sensitive to "bad" or different genes.

Take the Marsh Fritillary for example. It is possible with detailed study to identify the location at which a photograph was taken by examining the differences in the markings on the wings of the butterfly. Some years ago I was tested at this by a colleague at a BC meeting and placed every one of his photos correctly. I doubt I could do it now because I don't have the time to see all our Marsh Frit colonies in the summer. Back then I knew all of them.

Why do they vary like this? We don't know. We don't know why butterflies have the patterns they have on their wings.
There is an interesting book by a chap called Nijhoot on this but it doesn't explain everything. One interesting piece of information suggests that parasitism and melanin production might be linked. It is a complex matter.

One of the American species related to the Marsh Fritillary has actually been shown to be able to tell plants from its habitat apart from the identical looking plants from another site where the butterfly also occurs.

HarassedDad wrote:Talking of swallowtails - one local reserve lost all caterpillars accessable from the boardwalk one evening this year. Breeders claim that their swallowtails have been captive-bred since before the law protecting the swallowtail came into force. That's why they are allowed to sell the larvae and pinned specimens on ebay. That legitimate market is quite lucrative - pinned uk swallowtails go for £35 a time at the moment. Were the caterpillers stolen for sale or to replenish the genetic diversity of some breeders stock I wonder? Either way the existence of breeders selling specimens allows the poaching of butterflies from reserves in the same way as a legitimate trade in ivory provides cover for poachers in africa.

Interesting. You do make some assumptions but I think the final one is correct, but listen to this one.
It is only relatively recently that these British Swallowtails have appeared for sale by the bigger well known companies.
Worldwide Butterflies is an example. Before this the existence of a captive strain was known to a few people.
A friend of mine was given some and he reared them for photography. I remembered distinctly seeing that a yellow spot
on one of them was missing. An aberration that had no doubt appeared due to inbreeding exposing recessive genes etc.

A little while later I was at a trade fair where I saw a tray of these British Swallowtail specimens for sale. So I asked a question.
"So people are still breeding the British Swallowtail in captivity are they?"
I got the answer that they were all specimens collected before they became protected. Many of the specimens had this exact spot missing or misshapen.

Take the Swallowtails that used to exists at Woodwalton Fen until the 1950s.

Typo I presume. Swallowtails at Wicken Fen. Woodwalton was noted for its artificially maintained Large Copper colony.

Jack

Jack Harrison wrote:

Take the Swallowtails that used to exists at Woodwalton Fen until the 1950s.

Typo I presume. Swallowtails at Wicken Fen. Woodwalton was noted for its artificially maintained Large Copper colony.

Jack

Yes I meant Wicken Fen.

Pete Eeles wrote:...2. "The existence of breeders selling specimens allows the poaching of butterflies from reserves". Well - that's just not true, is it?
- Pete

I think the point being made was any legal sale of butterflies may be an encouragement for some to "cross the line".
Making sale of any butterfly, reared or not, illegal, would end that doubt...

Rogerdodge wrote:I take great pleasure every spring in visiting the Glanvilles at Sand Point. They are a real delight, and it is always a highlight of my year.
Now, they were an introduction many years ago. They disappeared for a few years, and have now reappeared.
This poses so many questions.
Did they really die out after the first introduction or survive in very low numbers?
Was the first introduction really a success, or was it bolstered each year with fresh stock?
Is the present population being bolstered? or is it self sustaining?.
Is it worth anyone studying this population? Because, if it is working it could hold important information. If it is being bolstered, then any study would be worthless.

No-one really knows...perhaps not even those releasing the butterfly, if they were different groups of people at different times.

The odd thing about the Sand Point Glanvilles is they do not behave like the textbooks say they should (or at least Hanski's book on metapopulation dynamics). They do not disperse, go extinct or recolonise, just staying in the same area. Possibly it is because the parasitic wasp that helps drive their behaviour is absent from Sand Point - but if so, why do they not colonise further afield?

Jack Harrison wrote:Well argued Roger.

While searching came across this on ukb about the Map Butterfly (species section)

This species was deliberately introduced in 1912 when the butterfly became established in the Forest of Dean in Monmouthshire, and Symond’s Yat in Herefordshire. The well-known entomologist A.B. Farn was so opposed to the deliberate introduction of a foreign species that, in 1914, he deliberately collected and destroyed every individual he could find. However, the ultimate demise of the colonies is believed to be the result of additional (and unknown) factors.

I can't see any mention of another short-lived introduced colony (1980s/1990s as best I can recall) in a wood near Oxford, possibly Wytham Wood which is owned by the University.

Jack

I have heard that this took place in the Chilterns near Wallingford, and that the police had words with the perpetrator.

Wytham has populations of all five British hairstreaks. Is it unique in this?

Paul Wetton wrote:If the gene pool becomes too small then introductions may be required to maintain the population along with habitat management etc. Introductions may not be from the same sub species or race as they may not be another similar population. In such circumstances I think that survival of an altered gene pool is preferable to loss of a species.

However, where the natural gene pool is large enough to maintain itself, then the introduction of foreign genes could adversely affect the genetics of the population and possible prevent speciation occurring over periods of time as a worst case.

Hi, just briefly (I'm not meant to be here - I should be getting ready to go out, lol)

using birds as an example, there was an extremely small population of endemic kestrels on Seychelles or Mauritius or somewhere (oh for a decent memory...) which were down to a mere handful of individuals. Less than twenty I think. If I'm remembering the facts correctly (if...) these birds were brought into captivity and cross-bred with a similar sister-species until numbers were sufficiently bolstered. Then, with judicious selected breeding, the original species was bred through from the hybrid population and was 'saved' from near certain extinction. As far as I'm aware that's more or less correct, crazy though it sounds.

So if, for example, 50 European Marsh Fritillaries were released into an existing British colony of Marsh Fritillaries their slightly different DNA could be absorbed and lost without any loss of integrity to the original British individuals? Unfortunately my grasp of inter-species genetics is somewhat less than legendary so apologies if I'm talking out of my *rse!

Gibster. Merry Xmas one and all, I recommend Paul Wetton's dvd if you fancy treating yourself (that's a pint you owe me Paul!)

Hi Seth

I'll be happy to buy you a pint.

I'm doing the same as you. My other half (better some say) is working at my local tonight so maybe I should do the right thing and go keep her company. Other side of the bar of course.

So I'll retire from these extremely interesting debates for the evening and wish you all a very happy Christmas day tomorrow. I hope anyone who receives one of my DVD sets is as pleased as evryone who has watched them so far.

To the pub.

The Oxon Maps were at Cholsey, by the river, near Wallingford but not in the Chilterns. I saw them there when I lived at Reading. I met a chap there I suspected of being the introducer.

Misha