Season (Adult / Immature):
National Status: Nb
Local Status: Rare and very local resident.
Local Record: Grade 4 See here for explanation
Flight time: Jun-Jul.
Forewing: M 34-42mm., F 44-48mm.
Foodplant: Mainly Poplar and Willow spp. and various deciduous trees.
|Year first recorded||1935||1985||1935|
|Year last recorded||2010||2006||2010|
|Number of records||29||8||74|
|Number of individuals||29||11||80|
For the region, we have a total of 74 records from 50 sites. Earliest record on file is in 1935.
For further information refer UK Moths.
Davey, P., 2009: A local and decreasing species in the British Isles, the larva living up to five years inside a wide variety of deciduous trees. A colony can occasionally destroy its host. The caterpillar exudes a strong goat like scent, a polyphenol called cossine (C16H24O2) that can be detected down-wind of an infected tree, and is reputed to be distasteful to birds (MOGBI Vol 2). When full grown (up to 100 mm long), the caterpillar is occasionally encountered well away from its host tree as it seeks a place to pupate, although pupation usually takes place within its host. The caterpillar spends its final winter in the larval state within a strong cocoon. The moth is sometimes observed at 'sugar' bait apparently attracted by one or more of the sugar ingredients. Without a tongue it is difficult to understand how the moth might benefit from such behaviour, but as cossine is a complex alcohol, the alcohol within the 'sugar' may attract the moth.
In Dorset, the moth was regarded as "generally distributed and not uncommon in the larval state when it could be occasionally fatally destructive to poplar planted for roadside ornament" (per W Parkinson Curtis manuscript). However, with fewer reports of the species in recent years, the declining trend nationally seems to be mirrored across the county. The few larval records in the past ten years or so, suggest a preference for oak (Quercus spp.), birch (Betula spp.) and sallow (Salix spp.) in deciduous woodland on sandy soil. An interesting observation by Brigadier H Warry at Upwey in 1953, related the occurrence of a freshly emerged female on the lawn ten yards from the nearest tree followed two days later by a freshly emerged male in the same place, and surmised infestation of the root of the tree. Conservation measures should include the retention of viable areas of mature oak-birch-sallow woodland on sites managed for conservation.