Now is the prime time to see scarlet tiger moths, one of our more striking invertebrates, which are currently immerging in good numbers and lending the reserves a splendidly exotic sheen. Their glossy black forewings with blobs of white and yellow and their scarlet hind wings make them easily identifiable at rest. Their strong presence on the reserves is due to the profusion of their caterpillar's food plants - comfrey, hemp agrimony, nettle, bramble, meadow sweet and sallow - most of which thrive here due to careful management on the verges and elsewhere.
Another lepideptoral observation of some significance is the current profusion of wainscot moths (obscure and silky for the most part) and their larvae on both reserves. The larval food plant of both these species is phramities australis (reed if you prefer) into the stems of which they bore to live out their larval stage. Great swathes of our reedbeds on both sites are withered, yellow and stunted rather than the typical verdant green sky-scraping growth more normally associated with late June and all because of these hungry, hungry caterpillars. I am trying to research the environmental trigger to this infestation and await word from our ecologist for a definitive answer, but we have postulated that less winter flooding may have resulted in fewer than normal eggs being washed away... seems plausible enough to me..?
There may be a cyclical element to wainscot 'lemming' years, the last being 2003 which didn't have any obvious lasting impact. Of course this great glut of invertebrate biomass will surely benefit other insectivorous reed dwellers like bearded tits, sedge and reed warblers may also benefit along with all other insectivorous passerines. Harvest mice can confidently be expected to tuck into the bonanza and thrive as will moth eating bats such as the serotine.
Southern Wainscot Moth.