Found in mature Oak woodland during mid to late summer, the Silver-washed Fritillary is one of our most recognisable and conspicuous woodland butterflies. It can be found throughout southern and central England, Wales and Ireland. Its presence in any particular woodland is dependent upon the type and structure of the woodland and how the woodland is managed. The size of a colony varies from wood to wood ranging from one or two butterflies to several hundred on the wing at any one time during its flight period.
Although this butterfly loves the sun it actually lays its eggs in the cooler, shady parts of the woodland where the larval foodplant Common Dog Violet grows.
The males which are a deep rich orange-brown with dark brown spots are particularly active during hot sunny days when you can see them patrolling up and down woodland rides searching for virgin females with which to mate. They will only occasionally stop to feed on thistles and bramble although late afternoon and early evening sees the males spending less time chasing the females and more time feeding.
Females which are slightly larger than the males with more rounded wings are golden brown in colour with dark brown spots. They initially lead a secretive life often feeding on bramble flowers close to the woodland edge where there is more dappled sunlight. Freshly emerged females will often display a green iridescence depending upon the angle which sun light fall on the wings.
The Silver-washed Fritillary is an unusual species because a small proportion of the female population have wings that are brown-green in colour rather than the normal golden brown. This form is known as f. valesina and can be quite common in some colonies.
Before they mate, a male and female will perform a wonderful courtship flight whereby the female flies in straight line while the male circles around her. First he flies quickly under her and then up and back over the top of her. He continuously repeats this over and over again until she accepts him.
While they are mating, both male and female will sit with wings closed but sunlight will encourage the male to open his wings. The female is more reluctant to open her wings while mating although both males and females may be the lead partner during the courtship.
After the pair separate and go their own way, the females become more active, feeding in the open or searching for a place to lay their eggs. The males continue to search for another female although as they get older, the need to feed rather than breed becomes more important.
New Forest, July 2011
A mating pair (the female being f. valesina) in a woodland clearing showed some interesting behaviour during the summer of 2011. It was sunny as we entered the clearing and first caught a glimpse of the pair descending from the tree canopy like falling leaves from a tree. The male was in charge of the flying as they landed amongst low growing bramble where he started to feed while the female sat motionless for several minutes. Then the sun was obscured by a cloud and the female took the lead and flew up into a nearby tree with the male still attached and hanging motionless behind her. They would sit wings closed on top of a leaf on the sunny side of the tree, orientated so that the male faced head-on in the direction of the sun. As the sun appeared from behind the clouds, the male opened his wings and for 5 minutes basked in the sunlight. He would then become fidgety and pull the female to the edge of the leaf before taking the lead, female still attached and motionless during the tumbling flight back down to earth, to the nearest bramble patch to feed again. As another cloud obscured the sun, the male would close his wings and the female would take control and drag the male back up into the trees. This behaviour repeated itself several times as we observed this pair for nearly two hours.