Glossosoma intermedium larva are a food source for fish that prey on insects.  They will sometimes leave the protection of their cases when food becomes scarce to drift downstream to find new algae sources.  During this time when they are floating in the water without their cases is when many of them are consumed by fish(Wallace 2011).

In North America Glossosoma intermedium is an intermediate host for a nematode that infects social wasps (Wallace 2011).

Some other insects can be found living in "stolen" caddisfly cases.  in the case of dance flies it is thought that they eat the caddisfly larva and then live in the case.  Midges use the cases to escape the stream current and predators while gaining access to food (Vinikour and Anderson 1981)