Grayling to moth trap

[Gibster]

Hi all,

I regularly visit the excellent Portland Bird Observatory website with its daily bird/butterfly/moth updates. This morning they discovered a Grayling in one of their moth traps.
I just wondered why a Grayling would be wandering around Portland after dark (ooh err, that sounds a bit iffy already! )

The species occurs on the island, but only very rarely appears in the vicinity of the Bird Obs area itself (and presumably this would refer to individuals disturbed by day). Is this just local dispersal? Or maybe a primary migrant from the continent? I've heard of Red Admirals coming to MV light, and assumed these were primary migrants, but never a Grayling. Are they occasionally recorded in odd places, maybe indicating a continental origin? Is Grayling known for post-breeding dispersal? My books don't seem to hold any answers. I'd always assumed that Graylings were a pretty static species, especially given the substantial number of recognised geographically-isolated subspecies occurring in Britain.

Thoughts please, anybody?

Have a peek at http://www.portlandbirdobs.org.uk/aa_latestnews.htm for the original account.

Cheers,

Gibster.

[grumpy]

Hi Gibster, I used to run an MV light in the garden in the '70s, I have had Small Tortoiseshells come to MV. I lived in landlocked Derbyshire both then and now. Also had a very annoying Robin who used to beat me to it in the mornings ! Clever little critters ! The cats from the local farms (one either side) also queued up to swat incoming during the night, despite this I still managed some decent records.



best wishes

Dave C

[Reverdin]

I had a Wall Brown come to my moth trap last year, and a Painted Lady once as well.... maybe they will all do it if disturbed by the light from their roost.

[ChrisC]

can't help with grayling dispersal but can add purple hairstreak to the list of moth trap visitors. but i was wondering the other day about Portland whether moth migrants were attracted by the light house light which i'm pretty sure must visible from a few miles away.

Chris

[Dave McCormick]

I have had a red admiral in my 6W Heath trap before, thought it could have been disturbed by light and fell out of the oak tree the trap was under and then into the trap. I have often thought it could be why some caterpillars come to traps, maybe disturbed by light and when distorted, crawl towards it? I know some would be looking for a place to pupate, but some I have had in my trap were not fully grown. Some could have been my disturbing where they would be feeding, by having a trap there and they crawl up it when trying to get past it.