Species alerts

Quagga Mussel - Dreissena rostriformis bugensis

Quagga Mussel - <em>Dreissena rostriformis bugensis</em>

This is a species alert issued as part of the GB rapid response protocol:

In October 2014 Quagga Mussel was found in Wraysbury Reservoir and the Wraysbury River, a tributary of the River Colne, near Egham, Surrey, and subsequently in a number of other waterbodies. This is the first UK record of this species.

The Quagga Mussel (Dreissena rostriformis bugensis) is a highly invasive non-native freshwater mussel from the Ponto-Caspian region, very similar to Zebra Mussel. It can significantly alter whole ecosystems by filtering out large quantities of nutrients and is also a serious biofouling risk blocking pipes smothering boat hulls and other structures.

There is no effective eradication method for quagga mussel once it has established in a reservoir and the downstream river system. As recommended in a recent review commissioned by Defra of options to deal with the arrival of quagga mussel, the best method of slowing the spread of the quagga mussel is by applying better biosecurity through the Check, Clean, Dry approach.

You can learn more about biosecurity here: www.nonnativespecies.org/checkcleandry

Further sightings should be reported online using this reporting form:

Or send an email with a photograph and location details to: alertnonnative@ceh.ac.uk

A briefing note for this species is provided below, along with information on identification, biosecurity and other resources.

Quagga Mussel resources:

[Image courtesy of David Aldridge of the University of Cambridge]


Asian hornet - Vespa velutina

Asian hornet - <em>Vespa velutina</em>

This is a species alert issued as part of the GB rapid response protocol:

Vespa velutina, sometimes known as the 'Asian hornet’ is an invasive non-native species from Asia.  It has recently arrived in France where it is spreading rapidly.  As a highly effective predator of insects, including honey bees and other beneficial species, it can cause significant losses to bee colonies, other native species and potentially ecosystems.  

Not yet present in GB, but it is considered likely to arrive soon.  The places it is most likely to be found are in southern parts of England (it may be able to cross the channel from France) or goods among which it could be accidentally imported (such as soil with imported pot plants, cut flowers, fruit and timber).  Active months between April and November (peak August/September).  Inactive over the winter, so the most likely time to see this species will be early next year.

Sightings should be reported online using this reporting form:


Or send an email with a photograph and location details to

Do not under any circumstances disturb or provoke an active hornets’ nest.

Asian Hornet resources:

Guidance for bee keepers: can be found on BeeBase.

[Image courtesy of Jean Haxaire]


Water Primrose - Ludwigia grandiflora

Water Primrose - <em>Ludwigia grandiflora</em>
This is a species alert issued as part of the GB rapid response protocol:

An invasive non-native plant from South America which has become a serious pest in other countries, including France, where it smothers water bodies reducing the numbers of native species and potentially increasing the risk of flooding.

It has started to be found in some parts of England and Wales.

If you think you've seen it, check with our Identification sheet.

Sightings should be reported:
Further information:

Carpet Sea-squirt - Didemnum vexillum

Carpet Sea-squirt - <em>Didemnum vexillum</em>

This is a species alert issued as part of the GB rapid response protocol:

Carpet Sea-squirt (Didemnum vexillum) is a highly invasive non-native marine animal that could threaten conservation, fishing and the shellfish industry.

Thought to be originally from Japan, it has become a pest in other countries by smothering native species and interfering with fishing, aquaculture and other activities.  It has recently been found in some marinas in England and Wales and there are strong concerns that it will spread more widely.

Use this webpage to report your sighting:

Or email:

alertnonnative@ceh.ac.uk

Further information:



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