Groynes or break waters are usually man-made. Groynes often contain food options and also habitats for aquatic plants. When waves and currents hit the groynes, deep parts are created in their sides, and they can whirl food options up into the water column, which benefits the hunting predatory fish.
Even though walking around on rocks along the coast may feel annoying, it’s often a good indicator of the presence of optimal bottom conditions for the sea trout and its food options. Everything from pebble to huge chunks of granite provides cover for sand hoppers, shrimp, and small fish. If there are waves, these food options are easily whirled up into the water column. A rocky bottom can be good all year round, but especially so during the cold months with few food options in the deeper water. A rocky bottom at a good depth also attracts other predatory fish such as cod and garfish.
In many fishing spots, large areas of the bottom are covered in sand, and often the coastal angler will skip these areas since they don’t seem like much. However, it’s worth considering that many small fish like sand eel and sprat often migrate across the sand bottom, and they have sea trout and other predatory fish chasing them. On days with waves, unclear water, or dimmed lighting, you’ll likely find predatory fish in these areas. The sandy areas along the deeper water or close to dark areas can be true sea trout magnets.