The brown trout (Salmo trutta morpha fario and S. trutta morpha lacustris) and the sea trout (S. trutta morpha trutta) are fish of the same species . They are distinguished chiefly by the fact that the brown trout is largely a freshwater fish, while the sea trout migrates to the oceans for much of its life and returning to freshwater only to spawn. Major Connemara Brown trout fisheries: All rivers and most big lakes. In Connemara fishing for Brown Trout is regulated. The brown trout (Salmo trutta morpha fario and S. trutta morpha lacustris) and the sea trout (S. trutta morpha trutta) are fish of the same species. They are distinguished chiefly by the fact that the brown trout is largely a freshwater fish, while the sea trout migrates to the oceans for much of its life and returning to freshwater only to spawn. Sea trout in the UK and Ireland have many regional names including sewin (Wales), finnock (Scotland), peal (West Country), mort (North West England) and white trout (Ireland). The brown trout is considered to be native to Europe and Asia, There are also landlocked populations far from the oceans, for example in Greece and Estonia. Few pure native stocks are thought to exist due to restocking with bred fish. The remaining pure stocks are thought to exist only in Corsica and some Alpine streams. Brown trout can live to ages of 20 years. It is a medium-sized fish but it can grow to 20 kg or more; In most Connemara lakes and rivers a mature fish is likely to weigh 1 kg (2 lb) or less. On Sept. 11, 2009, a 41.45 lb (18.80 kg) Brown trout was caught by Tom Healy in the Manistee river system in Michigan, United States. It usually migrates from lakes into rivers or streams to spawn. Some stocks spawn on wind-swept shorelines of lakes. The spawning behaviour of brown trout is similar to that of the Atlantic salmon. A typical female produces about 2,000 eggs per kilogram (900 eggs per pound) of body weight at spawning. There is a high proportion of death of males after spawning and probably fewer than 20% of female recover from spawning. Brown trout sometimes do not actively feed until the late afternoon or early evening but when the weather is cool they will feed during the day as well. The largest browns feed under cover of darkness. In fresh water, the diet will frequently include invertebrates from the stream bed, other fish, frogs, mice, birds, and insects flying near the water s surface. The high dietary reliance upon insect larvae, pupae, nymphs and adults is what allows trout to be a favoured target for fly fishing. Brown trout can be caught with lures such as spoons, spinners, jigs, plugs, plastic worm imitations, and live or dead bait fish. Freshwater brown trout range in colour from largely silver with relatively few spots and a white belly, to a brassy brown colour that fades to creamy white on the fish s belly. It has medium-sized spots surrounded by lighter haloes. Considerable variation can be found between and within brown trout populations. Brown trout are not considered to be endangered but some stocks are under various degrees of threat due to habitat degradation and over fishing. Increased frequency of excessively warm water temperatures in high summer which reduces the oxygen dissolved in water can cause summer kills of local populations. This can be made worse by eutrophication (algae growth that uses up the oxygen in the water) of rivers due to pollution from the use of agricultural fertilizers within the drainage basin. Scottish and Irish sea trout populations in recent years have seriously declined possibly due to infestation by sea lice from salmon farms. Overfishing is a problem where anglers fail return mature female fish into the lake or stream. Each large female removed can result in thousands fewer eggs released back into the system when the remaining fish spawn. Cover or structure is important to trout, and they are more likely to be found near submerged rocks, undercut banks, and overhanging vegetation. Structure provides protection from predators, bright sunlight and associated high water temperatures. Access to deep water for protection in winter freezes, or fast water for protection from low oxygen levels in summer is also good for the health of Brown trout stocks.
