The muddy and soft bottoms are often found in inlets, fjords, and brackish areas where outflow from rivers or drainage canals has transported sediment for many years. At the right times of year, these areas offer some fantastic fishing. From late fall till spring, the soft bottoms tend to be where the sea trout, for instance, can easily find food such as bristle worm, goby, and shrimp, since this type of bottom is a good heat insulator during winter.
Along with the eelgrass, bladder wrack is the most prevalent aquatic plant along the Danish shores. This seaweed attaches itself to smooth surfaces such as rocks, gravel, and other variations on the bottom. The bladder wrack is a good hiding place for food options and fish. Bottom conditions with bladder wrack are good indicators of fish being nearby.
This aquatic plant functions as a brilliant hiding place for the small food options, and simultaneously they oxidize the water around them, which provides small fish, shrimp, and sand hoppers with good living conditions. The eelgrass is also used as a resting place for the sea trout when it migrates along the coasts and particularly in late fall when the trout are headed for the river.