Thursday, 30 August 2012

Autumn approaching

An Article by Heather Martin

It's beginning to look and feel rather autumnal in the wood. Yellowed birch and poplar leaves are already fluttering down and the Hawthorn (Crataegus monogyna) berries are quite colourful.

Dragonflies hunting for prey perform aerial acrobatics around the clearings, also darting and swooping along the rides. When they perch to rest on the tips of branches, there's a chance to marvel at their beautifully patterned bodies and huge compound eyes. I managed to photograph a male Common Darter (Sympetrum striolatum) which can be identified by its orange-red abdomen and the two large yellow patches divided by a darker reddish-brown panel on the side of its thorax.

Also a male Migrant Hawker (Aeshna mixta).

Common spangle galls housing the asexual generation of the gall wasp Neuroterus quercusbaccarum are scattered liberally on the undersides of oak leaves. They will fall down into the leaf litter where they will spend the winter months, then in spring adult gall wasps emerge to lay eggs in the oak buds. These develop into green currant galls from which adults emerge in the summer, mate, the females laying eggs on the underside of leaves to start the whole cycle again.

There are nowhere near as many insects about now as there were a few weeks ago and this pale, delicate looking Oak Bush-cricket (Meconema thalassinum) was so well camouflaged on a leaf I almost missed noticing it!

Hunting for small insects amongst the foliage was a Spiked Shieldbug (Picromerus bidens) and it is possible to see the adults until November. The species usually overwinters as eggs.

This very hairy little Pale Tussock moth (Calliteara pudibunda) caterpillar was crawling across a chestnut leaf. The larva will grow slowly until October, then pupate to emerge as an adult next May.

Finally on perhaps a rather unsavoury but interesting note is a photo of a strikingly coloured Burying beetle - (Nicrophorus vespilloides) with mites attached to it. It appears that these may not actually be harming the beetle but merely hitching a lift. The beetle needs to lay its eggs in the corpse of a creature that it buries. The mites need to feed on the eggs and larvae of flies that might have found the prize first so the beetle provides transport and the mites consume the competition for the food source. Win, win situation!

All photos by Heather Martin (30/08/2012)

1 comment:

  1. We've had loads of dragonflies too, nice to have a bit of warm weather for them at last...