Sea Trout are basically brown trout that migrate to sea at an early age, just as salmon do. The purpose of the sea journey seems to be to find richer feeding grounds where they can grow to maturity before returning to the freshwater to spawn and begin the life cycle all over again. Brown trout and sea trout share a common ancestor. A brown trout is a sea trout that did not go to sea.
Sea Trout unlike salmon, feed in fresh water but not much. They certainly do not feed with the same verocity as brown trout, their stomachs are never full! Frequently their stomachs are empty or only containing a few food items of midges or small fly.
Small sea trout are known as finnock, peal, harvesters or juniors depending on where you are and what time of the season it is. Medium sized sea trout are usually in the one and half - three pound range. These are frequently caught by anglers. These fish have spent one or two winters at sea feeding.
The big sea trout range in sizes from four to ten pound. They are not plentiful but the type of fish sea trout anglers dream of catching atleast once in their lifetime. These trout are multi spawners. After spawning in November they return to sea swiftly to feed at sea for three or four months and return again to fresh water in prime condition.
How do you tell the difference between Salmon and Sea Trout? Salmon (I) can be distinguished from large sea trout (II) by a more streamlined shape, concave tail, slimmer tail wrist, upper jaw reaching no further than rear of the eye, few if any black spots below lateral line, 10-15 (usually 11-13) scales counted obliquely forward from adipose fin to lateral line – trout have 13-16.