The BBC reports on an invasive species of shrimp found in the Grafham Water reservoir in Cambridgeshire. Originally from the region between the Black and Caspian seas, it's thought to have spread to Western Europe via the Danube. Apparently it's a vicious little beastie that kills all sorts of other water fauna and could threaten them: native shrimps, water boatmen, even fish.

Should we worry? As with so many similar stories, it does raise the difficult question of whether we should or shouldn't interfere in the natural comings and goings of species. It's no doubt gone on down the millennia before we were on the scene, with vast numbers of species dying out and new ones coming to prominence before maybe fading away themselves. We seem to be keen to stop time and freeze the natural world as it is – but that sounds fairly unnatural in itself.

DodgyRoof
The rigours of the weather even cause home maintenance problems for blue tits. The left-hand part of the roof is peeling off the base unfortunately, but given they're happy to live with a whacking great hole in their front wall, is it a problem?

CommonDarterDragonfly

Walking along a leafy residential street yesterday I came across this critter sunbathing on a fence. It didn't seem to mind me poking an iPhone in its face to get this picture, and dare I say it's not a bad picture from a phone camera (with some simple manipulation afterwards).

This is a Common darter, a surprisingly small dragonfly to see in the flesh up close – not quite 5cm long from head to toe. Apparently it's common to see them sunbathing like this.

FurryCaterpillar

What is this furry black caterpillar? it has an orange stripe down each side too but that's hardly visible here. My best guesses, from finding similar pictures on t'Internet are that it's a White ermine moth caterpillar. Quite a beautiful moth, earning its name well. I also stumbled across this page showing how Ermine moths can make their presence felt in an almost horror-movie manner, coating whole cars and trees with silk.

The BBC reports that Red swamp crayfish have been found in London's Regents Canal. Like the Signal crayfish this is an American invader that threatens to oust the smaller native crayfish, though it's not such a big-clawed lobster as the Signal.

Mushrooms

It seems that it's that time of year when mushrooms pop up everywhere. I even found a small one in the pot of coriander growing on my windowsill! The ones above were growing at the foot of a tree in woodland.

How do you know when you can eat wild mushrooms? Easy: just don't, ever, unless you're a triple black-belt fungus identifier, and even those people sometimes get it wrong and end up in A&E.