Killer and demon shrimp

Killer shrimp and demon shrimp are two freshwater shrimp species. Individually they are highly invasive, but we now have both in the UK, which is worrying for our freshwater habitats.

KIller shrimp on white background Killer shrimp, copyright GBNNS

Native to the area around the Black Sea, both shrimp species have spread over western Europe in the last 20 years, most probably through commercial shipping. Killer shrimp were first discovered in the UK in 2010, while demon shrimp were first found in 2012.

More is known about killer shrimp, which live for about one year and are fast breeders. Females able to produce three broods, each with an average of 150 eggs per brood. Killer shrimp can tolerate a range of environmental conditions, but they prefer to colonise waters with moderate to slow flow speeds, only using faster-moving water to drift to new locations.

Killer shrimp are considered to be one of the most damaging invasive species in Europe, with the potential to significantly affect the ecology of our waterways. They prey on a range of native animals, fish eggs and even young fish, but often kill prey and leave it uneaten. This alters the ecology of habitats they invade and could cause extinctions.

Both shrimp species and their eggs can easily be transported around in damp clothing and equipment, as they can survive for a surprisingly long while out of water. Please follow Check, Clean, Dry procedures when you are out and about.

Last date edited: 17 November 2020