Hanham trees shrouded in white ermine silk

The silk is not thought to harm the trees significantly

Six bird cherry trees have been covered in silk from thousands of nesting bird cherry ermine caterpillars.

The silk on the trees by the River Avon in Hanham helps to protect the insects against avian predators.

Senior ecologist from the Butterfly Conservation, George Tordoff said while it happened fairly frequently, when it did occur, it was "striking".

He said it was more common to see nests in the north of the country.

Bird cherry ermine caterpillars spin the silk as a way to protect themselves from birds

"The good thing is the trees aren't harmed by them although they lose their leaves a little.

"If you went back to the same trees in the late summer you wouldn't know it had happened."

The trees are a temporary home for thousands of bird cherry ermine caterpillars

The caterpillars transform into white moths with black spots