On Monday 6th June I visited Ainsdale Sandhills Local Nature Reserve to witness a spectacular event. An Irruption of White Satin Moths. This moth Leucoma salicis has a wingspan of 37 – 50 mm and the wings have a beautiful white satiny sheen.
The moth is quite rare in the UK and also very localised. The thousands of moths are all concentrated in an area of about 200 metres by 150 metres
On 24th May I found the caterpillars devouring the leaves of the Scrub Willow bushes in the dune slacks south of the Discovery Centre. The young caterpillars over-winter on these bushes and somehow survive when the slacks are flooded. They resume feeding when the new leaves appear and when I visited some had started to pupate.
The caterpillars spin a loose cocoon between leaves and the pupa are glossy black.
I now had to be patient and wait 10 –14 days until the adult moths began to emerge.
On 1st June when I visited there were very few caterpillars, most had pupated and I counted just four adult moths.
By the 6th June everything had changed. The moths had started to emerge and were flying around in their hundreds. it was like walking through a snowstorm. I wanted to get an image of a moth emerging from the pupa but although I was there early in the morning I did not manage it. I did though see several in the process of expanding their wings.
During this wing expansion phase the wings are a beautiful buttery yellow in colour.
As soon as the wings are dry the males take to the air in an eager search for a mate.
Soon the females are laying their eggs and the cycle recommences.
It was a fantastic event and I could indulge my two passions, walking and photography. I feel very fortunate that this all occurs within 10 miles of my home. What will I find next?