Ruffe refers to a species of fish found in parts of the UK, northern Asia and the great lakes; this is a fresh water fish meaning that it is only found in the inner regions of the planet. The fish is a smaller member of the perch family and rarely grows beyond beyond 5 inches; one important thing that you should note is this is an invasive species, meaning that if it is introduced to a new environment/ecosystem it will take over.

Ruffe reproduce faster than other species of fish, this makes them a threat to other species. When they were introduced into the great lakes of North America the results were and are still unfortunate, what happens is Ruffe compete with other fish for food. And due to the fact that they eat other fish’s eggs and they multiply rapidly they become a danger to the ecosystem.

How to spot Ruffe

Learning how to spot invasive species of fish is very important because you can help in conservation efforts, when you spot this type of fish in areas that it’s not native to, you have a responsibility to report to proper authorities.

Generally the fish is very slimy when you handle it, lengthwise it usually measures less than six inches. Visually the fish resembles perch but only on a smaller scale. The fish has no scales on its head; the mouth is slightly downturned and has a very large dorsal fin.


Ruffe diet consists mainly of fish egg, larvae, aquatic bugs, zoo benthos and small aquatic bugs. The fish keeps its diet even when moved to new environments.

When it comes to matters reproduction Ruffe reproduce at an extremely high rate, a single female can lay more than 200,000 eggs in a single year. Ruffe spawning season starts from the month of April all the way up to June.

How they spread

As an angler you should understand that this is a pest, therefore if you use it as a minnow you may contribute to its spread. The primary way the fish spreads is through humans, For instance, when you dispose off unwanted bait. As a consequence of this, It is recommended that you never transport live Ruffe, if caught there maybe consequences depending on laws in your area.

How they affect other species

Ruffe have two major advantages one their side, one they multiply quickly and two they can survive in all sorts of environments. Their numbers means that they consume lots of food; this is bad because other species of fish of fish won’t find food even if they feed on other fish. Look at it this way, before most species of fish start feeding on other species they first rely on primary food sources such as larvae which are annihilated by Ruffe.

Simply put they reduce the food supply in effect starving the other species of fish.

How to help stop their spread

You can help spread the spread of Ruffe by doing the following:

  • Don’t release any type of fish from one water body to another
  • Don’t transport live Ruffe
  • Report to authorities when you find them in areas they are not common in