Look at the photo carefully. Can you see him? I spotted this large écrevisse, crayfish, at the dam end of the middle lake yesterday. He’s the biggest one I’ve seen for a while. He was covered in silt and lying low in the water so I couldn’t make out if he was friend or foe.

Friends are the native French écrevisses. They are a few varieties of these and sadly all are now considered ‘vulnerable’. They are  the red-clawed crayfish (écrevisses à pattes rouges), the white-footed crayfish (écrevisses à pieds blancs) and the spindly clawed crayfish (écrevisses à pattes grêles ou turque).

The main foes are the signal crayfish from the USA. They are generally chunkier than the native varieties, have more red patches on them and have a distinctive spur just behind their pincers. There are also American and Louisiana crayfish.

What are American crayfish doing in France? As so often happens, like the ladybirds I was talking about just the other day, someone introduced them. In the first half of the twentieth century, crayfish plague wiped out most of the crayfish in Europe, so in the 1960s American crayfish were introduced to help boost European stocks. Sadly no one realised that these new crayfish also carried the crayfish plague. They were resistant to it themselves, but their poor stressed European counterparts weren’t, and so suffered from another dose. The signal crayfish are also taking over the territory of the natives, which is putting further pressure on their numbers. They’re found in most countries in Europe now, but haven’t made it to Ireland yet.

So a rather sad tale for French écrevisses.

When we first arrived at Les Fragnes, we often came across huge signals crayfish wandering up the drive or across the garden. Since introducing catfish into our lakes, their numbers have dropped considerably and it’s rare to see large ones, like the one I spotted above.

The nuisance crayfish can be fished all throughout the fishing season, usually Easter to the end of September. However, fishing for native crayfish is restricted to just a few days, sometimes only one, during the year, according to departément.

Crayfish are delicious. They’re like large prawns so whenever we trap some foreign invaders, we have a nice supper afterwards! Barbecuing works well.

There are detailed posters about the crayfish varieties here and here  so you can familiarise yourself with the wicked ones it’s OK to hunt down and digest, and the native ones, which really we should leave alone in order to protect France’s biodiversity.