Where do sea trout spawn?

They spawn extensively throughout river systems, normally choosing redd sites slightly earlier and in smaller streams (often 1 – 5m wide) than most salmon, although there is some overlapping of spawning timing and requirements, so that some sea trout redds can be ‘over cut’ by later-spawning salmon and grilse. [Hybridisation between salmon and trout has been shown to occur at a low level (overall about 1.0%), as detected by biochemical genetic methods.  The offspring tend to be morphologically intermediate between the parental species and thus are difficult to recognise. Fortunately, they are virtually sterile. Backcrossing to either salmon or trout is extremely rare. There is evidence from the UK and Norway that salmon which have originated in artificial culture are more likely than wild salmon to hybridise with trout.)