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Suffolk Natural History, Vol. 59
Occurrence of the Tissue Moth in chalk tunnels at Bury St Edmunds Observations have been made for 76 winters since 1947/48 mainly searching for bats but taking note of other wildlife on each occasion. Apart from bats there were spiders, mosquitos and other flies such as the drone fly, Eristalis tenax and most conspicuously, Herald moths, Scoliopteryx libatrix. These colourful moths were mostly found in the cooler outer areas of the adits where dim light penetrated. Numbers were never counted but historically on occasion there were perhaps up to 100 or more, although the number found in the last twenty years have noticeably reduced. On four surveys in winters, 29 January 2005, 31 December 2007, 5 January 2014 and 30 January 2016 single specimens of the Tissue moth, Triphosa dubitata, were found hibernating in the chalk adits. These were found generally deeper in the tunnels, more or less in areas of complete darkness. Because in each winter the surveys are conducted around the New Year (either before or after) and at the end of January, it was evident that either on the first or second search the moths were not present. This shows the moths enter or leave the tunnels in January. In Britain, these moths tend to be mostly found in areas with chalk or limestone substrates, predominately in southern Britain. Extensive research in limestone mines by this author particularly working in Wiltshire, showed often hundreds of specimens, sometimes gathered in clusters of up to 20 moths. In addition, at the Ketton Cement works in Rutland where one of the principal rocks is limestone, a large 90m long ‘cave’ was constructed specially for bats in the 2001. From the first winter after completion, numerous Tissue moths were found in hibernation together with some herald moths. Bury St Edmunds is about 90 km south east of Ketton. The caterpillars feed on buckthorn (Rhamnus catharticus) and alder buckthorn (Frangula alnus). The former prefers alkaline soils but the latter is often found in wetlands with neutral or even acid substrates.
Note there is a lot of variation in the colour of this moth but in these photographs taken in Wiltshire limestone mines, the one on the right is covered in condensation so appears much lighter than if it was dry.
Trans. Suffolk Nat. Soc. 59 (2023)