LUNAR YELLOW UNDERWING LARVAL SURVEY
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NOCTUA ORBONA (HUFNAGEL) LUNAR YELLOW UNDERWING LARVAL SURVEYS IN THE SANDLINGS DURING 2002 TO 2005 A. W. PRICHARD Introduction The Lunar Yellow Underwing Noctua orbona is a National Biodiversity Action Plan species of moth. In the latter half of the 20th Century the species underwent a national decline in its distribution and is now mainly known from areas of the Breck in Norfolk and Suffolk with only scattered colonies being found elsewhere in Britain. The moth is in its adult phase (Plate 10) from June through to October, with aestivation (summer hibernation) occurring during the hotter midsummer months, particularly July. It is a species associated with open dry habitats; acid and calcareous soils where fine-leaved grasses grow. It is in its larval stage (Plates 11 & 12) from September through to late April or May with the larvae feeding at night primarily on fine-leaved grasses. During the larval stage it may be readily found, where present, by searching with lights at night. The advantages of surveying for larvae are that the precise location and habitat used by the species can be identified and a more accurate assessment of populations can be achieved.
Map of all adult and larval Lunar Yellow Underwing records – half filled circles for adults and full circles for larvae.
Trans. Suffolk Nat. Soc. 41 (2005)