IT ieasy to imagine that the sheer strength and pace of a waterfall would batter aquatic wildlife to pieces.

In fact, all creatures living near these cataracts cope very well indeed. Fish such as trout and salmon shelter behind stones while smaller creatures such as stoneflies, mayflies, caddis flies and crayfish can live beneath smaller stones and let the current bounce over them.

In the last couple of weeks I have studied two contrasting waterfalls. Firstly I visited Aysgarth Falls in the Yorkshire Dales. This was just after heavy rain and the falls crashed down over rocks, the water stained brown with peat. The fish and the invertebrates all seemed to be surviving with no problems.

My second visit was to Tarn Hows in the Lake District between Hawkshead and Coniston. I walked the circular nature trail and from there I explored lots of tiny waterfalls. I carried a small net with me and beneath the torrent I found stonefly, mayfly and caddis fly larvae, while adult damselflies and dragonflies seemed to be flying everywhere.

This was wonderful but alas the warm atmosphere produced far too many mosquitoes, which gave me a few nips.