Nature - Oct 6

It is rather uncommon up here in the north.

The scientific name translates as 'the immodest spring beauty' - or, just as likely, the 'spring beauty' with little regard for such a (supposedly) feminine trait.

The one-time pickers in Kent - and the Kentish folk - finding it frequently on hops, called it simply 'the hop dog'.

On roses at Bandrake Head, near Oxenpark (near the foot of the Rusland Valley) and brought to me for identification, it turned out to be a moth caterpillar.

It was striking the larva of the pale tussock moth which, though found throughout England, may be uncommon about here.

As with so many other insects, the bright colour is a warning.

I understand that the caterpillar contains toxic material - quite nasty poisons - but unlike any other species, these toxins are not acquired from the food-plant.

The poisons are 'home-grown' - part and parcel of the caterpillar body, though how this was achieved or evolved is unknown.

There are a few hop plants growing wild in Low Furness - and probably more scattered throughout South Lakeland, but this is the first 'hop dog' I have seen.

It has been recorded and photographed in this area previously, and the larval food is not restricted to the true hop Humulus lupulus, a plant which few realise is a close cousin to the controversial Cannabis sativa, source of the drug marijuana.

The moth larvae will feed on almost any broadleaf - from birch to oak, elm to lime.

They are related to the notorious brown tail moth, Euproctis chrysorrhea, whose caterpillars, feeding on leaves of many tree and bush species, sometimes reach plague proportions.

These caterpillars are covered in stiff hairs, a protective device, which, breaking off when the larva is handled, may cause severe and prolonged irritation in contact with human skin.

I released the 'hop dog' onto briars (kept hopefully for rose grafting) and when last seen it was seemingly at home among bright and tender new dog-rose leaves.

Above, the house martins circled, sweeping low, rising high after insects too small to be detected in the air by human eye.

These plump little aerial acrobats seem to linger on in Cumbria much later than the swallows - now reduced to a few local individuals or pairs.

Some house-marts are still feeding young - marvellous to watch as the food transfer takes place, both birds on the wing, suspended in space even if it be no more than momentarily.

How do swallows and house martins thrive together, here throughout the breeding season? Is there any difference in the insects taken by the two species? House martins tend to take the smaller types and fly generally higher - but there is no fixed rule - and generally, the list of insects taken by either species seems to differ very little.

The martins will soon be on the way south, and seem to be gathering in groups to prepare for the long journey.

I have recorded groups (some of up to 40 birds) in places miles apart - varying from east Yorkshire to Furness.

Is there any significance that these places are near the coast?

One sad sight of autumn was the flattened prickles of a hedgehog, a road casualty.

Judging from the size, this was an older animal - but one either unlucky or inexperienced (or both) when dealing with crossing roads and traffic.

Other but much more pleasing autumnal facets are the glorious leaf tints of horse chestnuts and damson, and ivy flowers crowded with a host of insects, particularly hover flies.

Wasps are plentiful - though here they run the gauntlet of folk fearful of the sting - or of such insects hibernating under the house roof perhaps to nest there next spring.

A solitary red admiral flits about the garden whenever the sun shines.

This North African species, flying here every year, will rarely overwinter here, or leave larva behind when leaving.

Does it try to return home? Or simply fade away en route south?