From late autumn until early spring the majority of bait fish around our coastline leave the shallows and head out for deeper water where they will be protected from the bitter cold of winter. Many of the species of shrimp that can be found on the other hand move into deeper tidal pools and onto shelves were the coastline is steeper.
Therefor shrimps are on the coastal sea trout’s menu the whole year round, and are found in great numbers all over Northern Europe’s coastline. These are particularly important to fly fishermen because they mature in the shallows where we do most of our fishing, and all sea trout fishermen should have at least a couple of good shrimp patterns in there fly box at all times.
The most effective colours for shrimp patterns in my experience are Red, Pink, White and Orange. Sometimes it can be rewarding to tie some very small shrimp flies in sizes 10-12-14 and in more natural mundane colours. Shrimps of all shapes and sizes are without doubt one of the most important food sources for salt water sea trout. Unlike other important seasonal foods like rag worms, sand eels and small bait fish, that the sea trout feed on throughout their first years in salt water.
Where, When & Why ?
A perfect small translucent shrimp pattern fished blind, is not the most easy prey for a sea trout to notice in a large body of water. But if you fish something that “ stands out in a crowd ” a little colour and movement, increase the chances of it being noticed and picked-up proportionally. Natural selection takes a favorable view of effective and adaptable feeding, a proficient predatory fish when feeding will maximize energy intake and minimize energy consumption. Predators quickly learn to avoid areas where there is little or no food. These rules also apply to the fish adapting their feeding locations and habits to the different seasons. So its paramount that the effective fly fisherman is aware of this and adapts his techniques, flies and strategy to that of the sea trouts feeding habits. This is especially important during the winter months when food is few and far between. Look for the signs, deeper bays with vegetation and structure, where prey can have sufficient food and cover from predators. If there is ice on the surface, pockets of open water generally indicate warmer water or flow. Both these elements will attract prey and predators alike.
Fast or Slow ?
Shrimp have three very different ways of locomotion. When foraging for food or resting on the bottom they use their front walking legs (periopods) for moving short distances on vegetation and other structure. When migrating or moving over larger distances they use their swimming legs (pleopods) These are located under the abdomen and undulate (like a Mexican wave) when swimming, and can be used to propel the crustacean in all directions slowly. But when alarmed or fleeing from a predator they use a contraction of their strong abdomen muscle which results in a powerful rapid snap of the tail plates (uropods) propelling the shrimp quickly backwards.
With this in mind one has a better understanding of the type of retrieve required to imitate a swimming or fleeing shrimp. Your retrieve will not only decide the speed of your fly but also its action in the water. If you know your prey and choose the correct retrieve, your overall chances of connecting will increase. If you choose the incorrect retrieve even the right pattern may not result in a take or even a follow.