The Spiny Water Flea competes with panfish and perch for food, thus reducing their numbers.

Spiny Water Flea Food Preference

The spiny water flea eats smaller planktonic organisms. Its diet consists mostly of zooplankton including Daphnia and smaller crustaceans. Bythotrephes can consume 10–00 prey organisms a day. It may also eat other small organisms it comes across.

Spiny Water Flea Distribution

The spiny water flea is native to northern Europe and Asia, and some parts of central Europe. However the water flea has spread in recent years to many areas throughout Europe including some ports and inland lakes outside its natural range through the ballasts of large ships.

The Spiny Water Flea was first discovered in North America in 1984 where it was found in Lake Huron, soon spreading to the other Great Lakes and their connected watersheds through rivers and canals.

Competition for Food

The Spiny Water Flea competes with panfish and perch for food, thus reducing their numbers. And, due to the spine, smaller fish are not able to feed on it.

The main source of food for the spiny water flea is Daphnia zooplankton, leading to competition with small and baby fish and also with native water flea species.

Daphnia zooplankton populations have declined in recent years though there is no conclusive evidence as to the cause, but many believe it has to do with the introduction of the Spiny Water Flea.

The spiny water flea is feeding on zooplankton is at risk of eliminating zooplankton species, and as zooplankton is the backbone of aquatic food chains, the Spiny Water flea presents a serious risk to the ecosystem of the North United States and Canada.

Spiny Water Flea

The Spiny Water Flea (Bythotrephes longimanus) is a crustacean with its straight tail spine averaging about 70% of its length. It is classified as a crustacean, but it resembles a flea in every way but the spine.

The Spiny Water Flea has a large eye that is usually black or red. It also possesses a pair of swimming antennae and four pairs of legs, of which the first pair is used to catch prey.