How times change - or Aphrodite lost!

[David M]

Back to the Marbled Fritillary for a moment...

...it seems that this species shows no evidence of breeding yet maintains a population year after year.

Does this automatically mean that numbers are being replenished artificially every year?

If that is suspected, is there any evidence? After all, one can't use the absence of evidence for one particular theory to promote evidence of an alternative theory. Just because there is no proof that there are larvae/pupae, etc of this species shouldn't automatically lead to the assumption that adult butterflies are being used to repopulate the area year after year (unless, of course, someone is caught red-handed doing precisely that).

If a butterfly is artificially introduced but goes on to establish itself, what (if any) are the criteria for consideration being given to proclaiming it eventually as a British species?

[Pete Eeles]

If a butterfly is artificially introduced but goes on to establish itself, what (if any) are the criteria for consideration being given to proclaiming it eventually as a British species?

If you really mean "what are the criteria for it being considered in any British list", then there are no official rules; it would be down to a given author (or webmaster ). UKB uses the list in Emmet and Heath, and Bradley and Fletcher. Neither contain "Marbled Fritillary" (unsurprisingly).

Cheers,

- Pete

[Gibster]

I find this thread fascinating. I've read it back a couple of times. As a "natural born listmaker/listkeeper" and one who likes to know that what I'm seeing really is what I'm seeing, I find the current debate educational and, at times, just a little disheartening.

My own personal view regards British butterflies is that an established species (ie with a self-supporting population doing just fine and dandy, minding its own business and breeding without human interference) that has not been introduced to the UK (ie colonized sometime after the Ice Age) is uniquivocably British and a 'wild' species. This would obviously include the usual annual immigrants. Those same established species which, perhaps through changes in land use or habitat amelioration, now depend upon our actions to safeguard populations against extinctions are just as valid and British as those that do not need our help. This is surely obvious? The only occasion this would alter would be if ALL wild individuals were caught and brought into captivity in order to maintain their existence. Look to the Kakapo as an example.

Then there are ther irregular visitors/vagrants which arrive in Britain unaided by man. Monarchs, American Painted Lady, Queen of Spain Fritilary etc. My own opinion is that species such as these are perfectly acceptable on the British list, but not as residents (except maybe as transitory ones).

Next come the adventives which seem to be a rather motley crew, tarred with the same messy brush. Were they ship-assisted? Did they arrive in exotic plant soil or with timber or even in a bunch of bananas? Can they be classed as 'genuine' British visitors or should they dwell in a murky no-mans-land? Well, that's obviously not for me to say!

But, for me, the crux of this thread relates to those species which have been deliberately introduced (legally and with permission, funding and research) or simply released into the British countryside (illegally and possibly without much thought, but maybe with much consideration for the species and it's exact requirements) and in what category they should be listed. Basically, if you see one, can you count it? Is it genuine? Is it wild? Is it self-sustaining? Will they still be there in ten years time? Do they need to be topped-up each year? Will they be British soon? Which authority decides? Says who?

Native Large Copper and Large Blue are extinct. Gone for good. Introduction (NOT re-introduction) of Continental stock is, in my opinion, not going to replace what has been lost. No amount of cross-breeding or inter-breeding is ever going to bring back the unique British subspecies. As far as I'm aware the ecosystems that these two subspecies depended upon are not in danger of collapse as a direct consequence of the butterfly's unfortunate demise. Hence the introductions are for purely aesthetic purposes. Large Blues are obviously doing rather well, although considerable effort is required to meet their exacting requirements. I saw my first Large Blues this year. It was a rather odd occasion for me, lacking much emotion other than "tick-and-run" and then off to see a 'proper' species. But that's just my slant on things and I'm obviously a bit mental!

In a previous post I asked who was 'in charge' of things. Who makes the rules? Apparently nobody does! Is the British butterfly scene really this relaxed? Doesn't anybody care? (deliberately flippant, my apologies) But seriously, how many 'exotic' species are out there breeding in our woodlands and meadows? Is anybody keeping tabs? This could be important. Jack stated that recent DNA work on a Marsh Fritillary colony has shown that they are not of British stock. We could be losing unique subspecies through interbreeding without even realising it. I find this point really rather important.

The Marbled Fritillary population mentioned in recent posts - are they breeding? Are they being topped up by persons unknown for reasons unknown? Shouldn't somebody be investigating? Surely it must be relatively simple to at least discover if they are self-supporting at some density?

The internet is, of course, a huge problem. It is easy to mail order exotic species from overseas and breed them at home. It must be almost impossible to police such practices. And why would anybody try to anyway? Unless the species is on a CITES Agenda no laws are being broken. It is down to the individual to determine what to do with surplus stock. A code of ethics should be adhered to. Doubtless BC has just such a Code, yet relatively few people are members, and being a member of such a body will not stop folk illegally liberating/deliberately introducing foreign species/subspecies into the countryside.

I apologise for the length of this post, I blame far too much beer and a strong sense of disatisfaction that not enough is being done to regulate/educate butterfly breeders. And that's (thankfully) the end of my rant.

Gibster (hic, one too many Stella's!)

[Pete Eeles]

Hence the introductions are for purely aesthetic purposes.

These reintroductions are not "purely aesthetic". They have been for genuine research purposes. Work on understanding the ecology of the Large Blue, in particular, has been applied to most of the related species on the continent to good effect.

Jack stated that recent DNA work on a Marsh Fritillary colony has shown that they are not of British stock.

If this is true then I agree - this is important and worrying.

The Marbled Fritillary population mentioned in recent posts - surely it must be relatively simple to at least discover if they are self-supporting at some density?

I think it's impossible to determine this unless the individual "owns up".

A code of ethics should be adhered to. Doubtless BC has just such a Code

Yes they do - http://www.ukbutterflies.co.uk/reports_policies.php

Cheers,

- Pete

[Matsukaze]

The Marbled Fritillary population mentioned in recent posts - are they breeding? Are they being topped up by persons unknown for reasons unknown? Shouldn't somebody be investigating? Surely it must be relatively simple to at least discover if they are self-supporting at some density?

BC and the local Wildlife Trust probably do not have the resources to do all that they would like to be doing, and a handful of exotic fritillaries at large in one location, that are very unlikely to constitute any harm and will probably die out in a year or two anyway, are not a high priority.

[Matsukaze]

the introductions are for purely aesthetic purposes

Assuming it harms nothing else, is this wrong?

[Gibster]

the introductions are for purely aesthetic purposes



Assuming it harms nothing else, is this wrong?

Hi Matsukaze,

agreed, by and large no real harm is being done so generally this is not "wrong" (although illicit releases are illegal under British legislation). Indeed if the habitat has been improved and sensitively managed for a given species then doubtless other species will also benefit the improvements. So a well researched introduction may overall be "right".

My own opinion is that butterflies are probably fairly 'safe' to release into the wild - although I am a purist and therefore don't particularly condone this action. Butterflies are unlikely to have much detriment to their immediate environment (unless small populations of a given subspecies are endangered through cross-breeding with a non-local subspecies). We're talking about butterflies, not rabbits in Australia, tilapia in America or mosquitoes in Hawaii (all environmental disasters!) But I'll use a mammal as an example anyway -

Take the Grey Squirrel, introduced to Britain by the Victorians in the 19th Century. Why? As a curiosity to satisfy the Victorian penchant for novelty. Not for food, not for hunting, not for breeding programmes. Nothing scientific, essentially just for aesthetic purposes. So, no real harm done. Hence not "wrong". Few at the time would disagree. Ring-barking and chewed wires are annoyances but nothing too sinister in themselves. Then the Greys encountered our native Red Squirrels. Research has shown that the Greys are in an ongoing phase of range expansion in Britain. They move into an area and any Reds in that area concede the ground and are lost. A winner and a loser, but hey that's life. But there's more. It is now clearly proven that the Greys carry a virus which will kill a Red Squirrel within 15 days of contact (the Greys show no symptoms and live a full life expectancy). The symptoms are not pleasant and ALL Reds show a complete lack of immunity. Basically, if they meet a Grey they will be dead within a fortnight which I find terrifying. Read about it at http://www.scottishsquirrelsurvey.co.uk/pox.html

Mammals transmit diseases to mammals. Grey Squirrels are not systematically destroying our butterfly populations! But I fear that introducing species or subspecies from other regions or countries may somehow contaminate or endanger our own unique butterfly diversity. I am not a scientist (clearly! ) and I'm probably spouting rubbish, but to return to your question - assuming it harms nothing else, is this wrong? - my reply would be, "we probably don't really know enough to know what harm may be done, so why do it - just in case?" Most certainly not for aesthetics.

[Gibster]

Gibster wrote:Hence the introductions are for purely aesthetic purposes.


These reintroductions are not "purely aesthetic". They have been for genuine research purposes. Work on understanding the ecology of the Large Blue, in particular, has been applied to most of the related species on the continent to good effect.

Hi Pete,

in such matters you very clearly know a heck of a lot more than I do. My perspective is that of a keen amateur with (mostly! ) ill based opinions and ideas. Let's be frank, when it comes to butterflies I'm a rank newbie!!! If I come across as a bit boisterous or opinionated then I'm misrepresenting myself (my girlfriend tells me I'm a nice person... )

Pete, you stated, "Rants are fine - I'll be formally introducing a UKB "therapy" section real soon "
I'm still waiting, I'm clearly in dire need of a lot of walls to bounce off!

All the very best

Ranter...er...I mean Gibster!

[Pete Eeles]

No worries - I'm particularly blunt after 2 hours sleep and a bad day at work

"The only thing that helps me maintain my slender grip on reality is the friendship I share with my collection of singing potatoes"
http://homepage.eircom.net/~odyssey/Quo ... Dwarf.html

Cheers,

- Pete

[Gibster]

And I thought we birders were the weird bunch....

[David M]

I suspect I'm going to get harangued for this, but I'm actually quite pleased Marbled Fritillaries are flying about in our country. God knows we've caused the extinctions of enough species (and the extreme decline of many more), so why be so 'anti' an artificial introduction such as this? Only a minuscule number of butterflies can be considered pests, so I really don't see what we have to lose.

[Gruditch]

It is illegal to allow any animal which is not ordinarily resident in Great Britain, or is listed on Schedule 9 to the Act 1981, to escape into the wild, or to release it into the wild without a licence. It is also illegal to plant or otherwise cause to grow in the wild any plant listed on Schedule 9 of the Act. Offences carry penalties of up to £5,000 fine and/or 2 years



And once again back to BC policy http://www.ukbutterflies.co.uk/reports_policies.php

Regards Gruditch

[Pete Eeles]

God knows we've caused the extinctions of enough species (and the extreme decline of many more), so why be so 'anti' an artificial introduction such as this?.

I completely understand the sentiment. But the reason to be cautious is that we don't know what the effect of the introduction of an alien species on native species is or could be. It really is as simple as that!

Cheers,

-Pete

[Jack Harrison]

Elm bark beetle, Horse chestnut leaf miner – these are both probably natural arrivals but look what damage they have done? Something like Marbled Fritillary might seem to be harmless. But there are bound to be factors that would not have been properly thought through.

For example, there is always the possibility that Marbled Fritillaries MIGHT bring with them some disease against which they have some immunity, or parasites with which they are in balance. Our truly native butterflies might not cope with these new challenges with resulting population crashes, certainly in the short term. Sturmia bella comes to mind (recently arrived parasite that affects Small Tortoiseshell)

Attractive as the thought might be for us to be able to enjoy non-native butterflies in “outdoor zoos”, the arguments are very strong that these introductions are not wise unless a huge amount of research has been carried out first.

Jack

[David M]

Elm bark beetle, Horse chestnut leaf miner – these are both probably natural arrivals but look what damage they have done? Something like Marbled Fritillary might seem to be harmless. But there are bound to be factors that would not have been properly thought through.

For example, there is always the possibility that Marbled Fritillaries MIGHT bring with them some disease against which they have some immunity, or parasites with which they are in balance. Our truly native butterflies might not cope with these new challenges with resulting population crashes, certainly in the short term. Sturmia bella comes to mind (recently arrived parasite that affects Small Tortoiseshell)

Attractive as the thought might be for us to be able to enjoy non-native butterflies in “outdoor zoos”, the arguments are very strong that these introductions are not wise unless a huge amount of research has been carried out first.

Jack

Fair points, Jack. I certainly wouldn't encourage people to release large numbers of 'alien' butterflies into the UK, but I admit I'd be quite excited if I DID happen to see a Marbled Fritillary in Britain.

From what I've read (mainly on here) there have been quite a few releases of non-indigenous stock over the years. Has there ever been an instance where this has been proved to have an adverse effect (like in the case of the grey squirrel)?