Trout are fussy fish.  Continued residence in any given stream is conditional upon the provision of a wide variety of river channel features for their use and enjoyment.   Deeper meander pools are just the ticket for adult fish to lounge around in, while riffles   are an essential habitat during those times when spawning and feeding urges cannot be denied (point bars aren’t too bad a place to spawn either, report the trout).  Oxygenated gravels make a good nursery, associated as they are with high egg survival rates.  Ox-bow lakes that connect with the main river channel will serve as an important refuge from predators – they also offer relatively warm water temperatures to young fish during their crucial first winter.  Indeed, such is the intimate connectivity between different landscape features and river ecology, that if even one vital component of their highly selective habitat is missing, then so too are the trout. For this reason, river management schemes that do not protect or restore a variety of landforms-as-habitats are usually looked upon as something of a disappointment by trout.

Read more about wild trout here.