The two large tortoiseshell butterflies at Church Ope Cove on Portland were certainly a surprise! Believed to have been extinct in the British Isles since the Dutch elm disease outbreak in the 1970's it seems, and I am not fully aware of the details, that there was a small release of specimens on Portland a couple of years ago and, obviously, at least one was a pregnant female. Any find of large tortoiseshell is going to be a surprise but there are a couple of other factors that make this all the more remarkable. The first is that, although they are a hibernating species in log piles and hollow trees in winter, they hardly ever survive until the following spring which is why they have not re-established themselves here. Secondly, previous records seem to have been from Tout Quarry and the Fortuneswell area on the west of Portland whereas Church Ope is on the east coast, not that far away but a new location. So, the question still to be answered is; is the large tortoiseshell recolonising Portland? If it is I expect that it is unlikely to spread to the 'mainland' but we will have to wait and see how it fairs.
Photograph by:Portland Bird Observatory
No longer a breeding species in Britain and the source of any specimens found is always uncertain!
Diary Note: 2nd March 2020 - Large tortoiseshell emergencePost date: Tuesday, 3 March, 2020 - 08:26
|Common Name||Large Tortoiseshell|
|Scientific Name||Nymphalis polychloros|
|Species Group||Nymphalid Butterflies Admirals and Fritillaries|
|Additional Identification Notes|