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Just what do we actually know for sure about Invasive Crayfish & Impacts on Fish??

The great strength of (good!) science is that it tells us how confident we can be that what you see is a true effect - or just part of the natural random variation in nature. As humans, we are so often "fooled by randomness" - we see faces in clouds and the image of the Madonna in Fried Chicken...

As one of many fascinating aspects of our own Prof. Jon Grey's research, he has contributed to the understanding of what invasive crayfish actually do "do" in our rivers. You can see his thoughts on the most recent National Crayfish Conference that he attended and contributed to here: NATIONAL CRAYFISH CONFERENCE.

Below you can enjoy some fascinating insights into what existing good quality science can tell us about invasive crayfish

Did you know that there are at least 7 non-native species of crayfish in the UK? What do we really know (by controlled measurements) about their impacts on our native fish - including trout and salmon? Is there a crayfish species that is worse for UK waterways than the signal crayfish? The answer to the last question is yes; but right now it is still only here in small numbers...




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