Misguided introductions

[Trev Sawyer]

I have heard that Heath Fritillaries have recently been spotted at Over Railway Cutting near Cambridge. The only realistic explanation for this is a that captive bred insects have been released there (as I don't think there is any Cow-wheat anywhere near that and to my knowledge, no such butterflies have ever been seen there before). These butterflies will therefore simply dissappear again.
The issue of artificial releases has been discussed elsewhere on this forum but I would like to flag up the practice again for discussion. Some releases (such as this one) may appear obvious, but others are less so. I believe those who do this genuinely believe that they are helping their chosen species, but it is not something which should be done by any individual without prior discussion with butterfly conservation groups. Anyone collecting data would have their results artificially raised by such activity, leading to a potentially misguided belief that the species is surviving well at the venue. Captive bred insects may hatch at a different time than the original wild versions, and if this is at a time when the food plant in that area is not available, the result is obvious. The practice may artificially increase the number of predators (ie parasitic wasps etc.) and condemn the original population of butterflies to an uncertain future.
Access to live insects via the web is becoming popular and is a great way to see the lifecycle of many species, but in many cases the resulting butterflies should not be released into the wild. It would be good to know if there is any official policy on how one works out which species are OK to release and which ones are not.

PS. It may be that the recent Queen of Spain Fritillary sightings in the UK have been (at least) supplemented with captive releases. How do we know which are genuine migrants and which are simply releases.

Trev

[Pete Eeles]

Thanks for resurrecting this topic Trev. I've been meaning to get hold of the Butterfly Conservation policy on this - and will contact Martin Warren to see if there's an online version available. If not, perhaps we can craft our own code of conduct.

This topic has been raised before. Take a look here:

http://www.ukbutterflies.co.uk/phpBB2/v ... c.php?t=43

and here:

http://www.ukbutterflies.co.uk/phpBB2/v ... .php?t=108

Cheers,

- Pete

[Matsukaze]

Hi Trev,

If you find the person who did this you could send them down here - I would be more than happy to decapitate them.

There are a couple of similar habitats around here which I would like to see better managed/protected. Those that would like to build houses on them, however, would be only too keen to claim that the rare butterflies that occur on the site were released there and never occurred naturally.

[Dave McCormick]

Stuff like this does make it more difficult to manage populations. You don't know if they are captive bread or just rarities. Its better if they are just rarities like naturally occuring queen of spain, not captive bread. I don't release captive bread, just ones I bread from wild.

[Pete Eeles]

Martin Warren kindly sent me BC's policy document on introductions and reintroductions. See:

http://www.ukbutterflies.co.uk/reports/ ... 202001.pdf

Cheers,

- Pete