Recording invasive species

Invasive non-native species are one of the greatest threats to biodiversity worldwide.

Quick to establish themselves, invasive species can threaten whole ecosystems and cause serious problems to both the environment and the economy. In Britain, the most problematic land-based invasive species are well known, such as the North American grey squirrel, which has nearly wiped out the UK’s native red squirrel, as well as the notoriously fast-spreading Japanese knotweed and rhododendron. Whilst a lot of research has been done on our land-locked invasive species, the impact of our invasive, marine species is less publicised.

Funded by Natural Resource Wales (NRW), and in collaboration with Succorfish, the Welsh Fishermen’s Association (WFA-CPC) trained twelve fishermen during 2016 to monitor their catch for invasive species and report their presence on a multi-purpose mobile phone app called Catch App.   This innovative app is helping to revolutionise fisheries management as it allows fishermen to instantly collect, record and share fishing data using just their mobile phones. Typically, this information would be recorded using the traditional method of paper and pen, which can result in hours of work for the fishermen!



Nigel Saunders, who works pots for whelks and lobsters, and nets for ray and bass

For this study, the selected fishermen have been monitoring their catch for eleven, pesky invasive species, such as the slipper limpet and the American oyster drill. One of the most concerning invasive species they’re looking out for is the presence of the American lobster, which could have a profound effect on the European lobster, as it is far more aggressive and carries a deadly disease that our lobsters aren’t resistant to.

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Nigel holding a slipper limpet he’s caught in Swansea Bay

Since the study launched, slipper limpets and wire-weed have been regularly recorded, whilst two American lobsters have been reported by pot fishermen operating in Tremadog & Conwy Bay. The WFA-CPC, NRW and Welsh Government are urging fishermen and merchants to report catches and sightings. ‘If a species does arrive in our waters, early detection is essential if any attempt at clearing is to be made. Reporting non-native species helps to protect commercial species by identifying sources of potential introduction and promotes good practice to minimise their spread.’ If you’re a fisherman and would like to participate, please contact Mark Gray:

For further information about the work of the Welsh Fishermen’s Association, sign up to their newsletter at www.WFA-CPC.Wales.



The American lobster caught in Tremadog Bay. Note its distinguishing features – red tipped spines on its rostum, underside of claws usually orange-red and olive green/greenish brown body

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