Inhabitants of a Brook

What determines a brook?

A brook runs over gently falling slopes and usually has a sandy or gravely bottom. As it runs over relatively flat terrain, it runs much slower than a mountain stream and has a lot more bends.

The Temperature and the oxygen content in particular can vary a great deal. During the summer months, the oxygen content drops significantly.

The aquatic vegetation is very bio diverse. Even plants that are not adapted to the current, like the flowering rush (Butomus umbellatus), the arrowhead (Sagittaria sagittifolia) and the water lily (Nuphar luteum) can thrive.

Animals of the Brook

Except for animals that inhabit the bottom, like the freshwater clam (Unio sp.) or the river snail (Viviparus viviparus), many species that live on the underwater vegetation can be found. These include freshwater shrimp (Gammarus pulex), larva of the banded demoiselle (Calopteryx splendens) and mayfly larva (Ephemeroptera) of different genus.

The surface is already calm enough for a group of animals to live on. This group is called pleuston. Water crickets (Velia caprai) can be found as well.

Brook or River?

Above a certain size - the indicator is approximately 1m^³/s - it is no longer called a brook, but a river. In general, the same things that happen in a brook happen in a river, but the bottom is already muddier.