We recorded this beautiful female Emperor Moth (Saturina pavonia) while undertaking a survey of a proposed wind farm site in the Wicklow Mountains this week. Emperor moths are the only Irish members of the silk-moth family. Emperor Moths are fairly widespread in suitable habitats; but it is really is a wonderful sight to see the female. Male Emperor moths fly during the day; however the larger females only fly at night time. The females are heavily laden with eggs so are unable to fly very far, and after mating lay most of their eggs very near the spot where they emerge. After laying around 100 eggs they will be lighter enabling them to fly, but only at night. It takes them about 2-3 days to complete egg laying.
The Emperor moth is one of the largest moths found in Ireland and it has a very distinctive eye marking on each of its four wings. The female Emperor moth releases a pheromone to attract the male moths, and it is understood that the males are able to detect the pheromones from several kilometres away. We saw some males first, and looked for and found the female. The brightly coloured male is easier to spot as it zigzags over open ground.
The caterpillars of Emperor Moths can be seen from May to August and are hairy and black when newly hatched. As they grow they change to green with yellow, pink or orange spots with each spot covered with black hairs. The caterpillars spend the winter in their cocoons, before emerging as these fantastic adult moths in April or May. For more on the Emperor Moth see this article. For other nice photos of the female and caterpillars see this post here.
The above observation was made on our way to vantage points during our bird surveys at this site. It is always worth keeping your eyes open. We are currently undertaking all the ecological surveys required for this proposed wind farm in the Wicklow Mountains. We are the leading independent provider of terrestrial and aquatic ecology surveys in Ireland. If you have a requirement for any ecology work please do not hesitate to contact us.