www.ukbutterflies.co.uk

I just read this report on the Sussex Butterfly conservation web site:

I had intended to travel to the Isle of Wight this week to catch up with the Glanville Fritillary but I had been tipped off that I could see them much closer to home in Surrey. In anticipation I travelled over the Hog's Back to a sand pit in Wrecclesham (SU818447) on Monday and sure enough, and much to my surprise, there were plenty of Glanville Fritillaries to be seen, possibly too many. I gave up counting after I had quickly reached 50 and there were hundreds, if not thousands of the them flying around everywhere. Although I have some misgivings about the merits of introducing a butterfly into a previously unrecorded site the Glanville is clearly thriving in its new home. (Richard Stone.)

Has anyone else seen Glanvilles at Wrecclesham? Maybe someone who lives around there should take a look?

Cheers
John

I'm within half an hour (traffic gods willing) of the spot - may try later in the week when more sun is forecast. A bit of an oddity, this one. I'll try and combine it with a quick squint at a nature reserve in Aldershot where PBF has been reported in the past.

Dave

http://wtp2.appspot.com/wheresthepath.h ... &oz=8&gt=1
The link is to my nerw favourite mapping site.

Thes Glannies are probably an introduction - and good luck to them!

I live nearby,so I went to have a look,with a few others.The weather was rather cloudy and not too warm.But there were many about.I am no expert,but they look like Glanvilles to me.This one had a damaged wing-the cold again?

Yep - definitely Glanvilles. I wonder if there is a captive-release programme via Butterfly conservation we aren't aware of?
Michael

I wonder if there is a captive-release programme via Butterfly conservation we aren't aware of?

Almost certainly not. I can't see BC sanctioning an introduction into an area where they have not been before.
I reckon it is just a private introduction.
I do not know much about captive breeding, but I understand that Glanvilles are particularly easy to raise (Pete?)

I have it on good authority that this is a release from a well-known Farnham-based breeder.

Yes, Glanville Fritillary are very easy to rear!

Cheers,

- Pete

Pete Eeles wrote:I have it on good authority that this is a release from a well-known Farnham-based breeder.

Do we know when they were released, i.e. how long the colony has been in existence? Presumably at least a year, unless the breeder released 100's of larvae or adults?

John W wrote:

Pete Eeles wrote:I have it on good authority that this is a release from a well-known Farnham-based breeder.

Do we know when they were released, i.e. how long the colony has been in existence? Presumably at least a year, unless the breeder released 100's of larvae or adults?

I don't know the details, but this is their 2nd or 3rd year, I believe. The colony is known to Surrey BC who are monitoring it (I think!).

Cheers,

- Pete

A response from the individual in question:

"The colony is now in its 9th year and was originally from 300 larvae from three batches of wild collected webs from Whale chine. Larvae certainly have an active parasite from these and will help over-population. I saw no adults for 3 years but when I thought I would release their captive cousins as post hibernation larvae I, much to my surprise, found larval webs - 39 in total after a cursory scan. The population last year was huge and plenty of larval webs covered the site. However these disappeared in late August due to very wet conditions. This winter and spring looked very poor and 5 webs seemed active. Much to my pleasure the adults have made a good show. They are normally 2-3 weeks behind their IOW folks and are certainly large and healthy. I have seen 3 aberrations to date".

Cheers,

- Pete

lee3764 wrote:What a great story! Well done to that breeder! Let's hope the Glanville Fritillary colony continues to thrive & prosper. If it has been in existance for 9 years then it should continue to thrive as long as the habitat continues to be suitable ie: continuous slippage or similar to help regeneration of the larval foodplant (Plantain).
Keep us all posted & I hope BC welcome this introduction. Without introductions/reintroductions (official under licence) during 1990's & 2000's then Devon & Cornwall would have lost it's Heath Fritillary colonies.
Cheers all,
Lee (Cornwall).

Yes, I welcome it too.

Wow!

And how many times all unawares have I driven past this spot on the A31 or the A325 on my way down to Noar Hill or Alice Holt? Well, the secret is out now... Let's hope they continue to do well. I wonder if there are any other similar bits of habitat nearby that they might naturally spread to?

Dave

millerd wrote:Let's hope they continue to do well. I wonder if there are any other similar bits of habitat nearby that they might naturally spread to?

I think that's a key question. It would be a shame if they are doomed to exist only in a tiny colony for ever.

It would be a shame if they are doomed to exist only in a tiny colony for ever.

I disagree.
It would be excellent if they remain as this tiny colony.
In my first post on this thread I said-

Thes Glannies are probably an introduction - and good luck to them!

My implicit support for this introduction is precisely because they will probably remain isolated, and not spread.
An alien introduction that spreads into the wider countryside can cause huge problems.
Grey Squirrel, Japanese Knotweed etc. etc.

Rogerdodge wrote:An alien introduction that spreads into the wider countryside can cause huge problems. Grey Squirrel, Japanese Knotweed etc.

Roger,
A good point, I did think about this briefly last night, but I can't see it happening. Firstly, what would the Glanville take over from? There are no other Fritillaries in Britain feeding off Plantain, and I can't see that they are at a more advantageous position via evolutionary behaviour etc. They are no more equipped to 'take over' than any other UK butterfly, though they are quite good middle-distance flyers. I presume that Glanvilles were originally a lot more widespread in Britain ('Lincolnshire Fritillary' etc) though the historical records aren't very good on this species. So at best they could be called a re-introduction? p.s. I'd love to see some round here, we have plenty of Plantain!
Michael

I was hoping to see them this morning before work (I start at lunchtime today) but after waking up to drizzle I decided to leave it until next week. I hope they will still be around then and I won't have left it too late.

Personally I think it's a great thing they are there, but then I don't really know the ins and outs of the harm they could possibly do...

Michael

They are no more equipped to 'take over' than any other UK butterfly

I am pretty sure that the Glanvilles will not challenge a resident butterfly for territory or ecological niche.
However, this is not my real concern.
I quote-

Larvae certainly have an active parasite from these and will help over-population.

What if these parasites from the Isle of Wight encounter another potential host species that isn't found on the Isle of Wight?
It is not beyond the realms of imagining that it could have a devestating effect on another species.
This is just one possibility of an unknown number considering how little we know of the effects of playing with ecology.
I stress that I am not a scientist, and I may be talking absolute drivel.

I am sure you are not talking drivel,Roger.
Perhaps just play it safe and come to the Isle of Wight to see them in their natural habitat.
Regards Peter