Orange spots in Gammarid shrimp

Riverfly monitors may be interested in a project which aims to establish the distribution of a fish parasite that uses the freshwater shrimp Gammarus pulex as an intermediate host. The parasite is a spiny-headed worm called Pomphorynchus. It causes the shrimp Gammarus pulex to develop either single or multiple orange spots in the body, like those in the picture above. These spots increase the chances of the shrimp being eaten by a fish, completing the life cycle of the parasite. We have contacted the project team to request some vials and collection instructions. So if you find an orange-spotted Gammarus during riverfly monitoring over the next few months, please preserve it in a wet tissue and either contact Jo or send it direct to the EA as per the instructions in the attached flyer.

For more in-depth information about the parasite and the project please see the following links.



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The Cleddau Trail Map

The Pembrokeshire Rivers Trust Cleddau Trail takes you on two 'Source to Sea' river journeys. Follow the Western Cleddau Trail to discover unspoilt natural habitats, home to migratory salmon and sewin, kingfishers and other wildlife. The Eastern Cleddau Trail follows the flow of Pembrokeshire's rainwater as it becomes drinking water.


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