Northern February red stonef ly
The Northern February red stonefly (Brachyptera putata) is a special species. First found in the River Clyde in 1838, it now mainly occurs in northern Scotland, particularly the north-east and Cairngorms. Outside of Scotland, it has only been found on the Usk in Wales and Wye, and nowhere else in the world. Nymphs are found in the middle to lower reaches of larger rivers, with good water quality and clean gravels. Winter sunshine is essential so they tend to avoid stretches of river that are heavily shaded by bankside trees. They seem to prefer deeper areas of flowing water where they live among large stones. It’s thought that they feed by gathering tiny fragments of organic matter from the bed of the river. The nymphs emerge from their eggs in autumn and grow rapidly through winter. They are sturdy with long antennae and tails. As the end of winter approaches in February the nymphs ready themselves to emerge from the water. The mature nymph climbs out of the water on to a rock, tree, or bankside structure such as a bridge support in the evening. Nymphs have been observed climbing up to two metres up a bankside tree, and their cast nymphal skins can be found above head height on bankside walls and bridges. Adults can be seen from February to April and they are often encountered as they bask in the sun on fence posts by the river. They have also been found under stones along the river side or resting on snow patches where they may be gaining warmth from sunlight reflected off the snow. Males have reddish wings, which are fore-shortened meaning they cannot fly. Females have fully-formed greyish wings with four black bands.
Can you help?
The last national survey for this species was in 2003. We desperately need to know where it now occurs. Winter is the perfect time to spot adult stoneflies as they bask on fence posts alongside rivers. It’s easy to get involved – take a picture of the stonefly and send it to scot[email protected] buglife.org.uk or tweet it to @buglifescotland with your name, picture, date, the river and location.
The February Red is 8-10mm long.