The Marbled Crayfish. Be on the lookout for this invasive asexual species in Ontario/all of North America ! Report any sightings immediately.

The Logjammer #Hoverfly Chalcosyrphus eunotus.

Found at a new site on a tributary of the River Churnet in Staffordshire.

Pedicia rivosa...simply one of my favourite true flies and a good indicator of species-rich, boggy woodland up on the North York Moors. Fen Bog today. @dipteristsforum.bsky.social #pediciidae #hairyeyes

Learn more on our work to protect white-clawed crayfish in Yorkshire:

www.ywt.org.uk/yorkshire-crayfish-forum

250-500 years ago, the freshwater white-clawed crayfish was recorded across much of England (although not Ireland). It is now steeply declining in Britain due to the introduction of the signal crayfish which carries crayfish plague. 🦞🤍 Map from my #AtlasOfEarlyModernWildlife #envhist #biodiversity

Absolutely crawling with #invasive #nonnative Signal Crayfish in Culford Stream including one (lower right) that seemed to be diseased. Note the diagnostic red under claw of this angry one, to separate it from the native White-clawed.
#crayfish #chalkstream #signalcrayfish
3/5

The new and improved second edition is out! Here is the link for the free download: www.invadingspecies.com/downloads/in...

balkanrivers.net/en/news/2025...

Skradinski Buk, the longest waterfall on the Krka River, created by tufa barriers, islands and lakes- excellent location for our @qmulsbbs.bsky.social UG field course 💦🐟, with @claraandthebees.bsky.social and others

Just landed: "Riverfly Handbook" by Craig Macadam, a must-have for anyone who loves dipping into streams and discovering the tiny wonders within. Mayflies, stoneflies, caddisflies... it’s a whole world down there. Dive in!

#Entomology #FreshwaterLife #NewArrival @amentsoc.bsky.social

I went out with @nickmott7.bsky.social from @staffswildlife.bsky.social last year as we went looking for spined loach on the trent and have a go for stone loach also.

www.youtube.com/watch?v=rLNN...