Invasive beasts and where to find them !

When it comes to stopping the spread of Invasive Non Native Species, anglers can make a huge difference, says Angling Trust Invasive Non Native Species Manager Emily Smith.

The phrase ‘’an ounce of prevention or pound of cure’’ is often used to talk about invasive species, where stopping their initial introduction is seen as being more effective than trying to remove them afterwards. This is because once an invasive species has established in the environment, it can often be impossible to completely eradicate. It is particularly true for freshwater species where the connectivity of catchments facilitates the rapid dispersal of invasive species into other water bodies. For example, since 2010 at least three new freshwater species have been reported in the UK including the killer shrimp, demon shrimp and quagga mussel. These species have subsequently spread further into other UK water bodies, replacing native species and causing major changes to the food web. It is estimated that invasive species currently cost the UK economy around £1.7 billion a year. As invasive species continue to spread and new invasive species establish, it is expected that this cost will continue to increase.

Invasives such as Floating Pennywort have already invaded our shores and can have a huge impact on freshwater habitats and a very negative impact on fishing.

So where are they coming from?

Preventing the establishment of new species is no easy task and requires an understanding of how they are being introduced into the UK in the first place. Invasive species have been introduced into the UK from all over the world following patterns of human movement. More recently, there has been an influx of species from Eastern Europe, particularly from the Caspian Sea, Anov Sea and Black Sea. This area is often referred to as the Ponto-Caspian region. As canals and rivers have been joined up for shipping it has allowed species to spread from the Ponto-Caspian region into Western Europe.

The round goby is present in waters in Netherlands and eats the eggs and young of native fish

Research being undertaken by the Angling Trust indicates there are at least 20 invasive freshwater species present in the Netherlands that could become widespread if they were introduced into the UK. They include three goby species that have the potential to have significant impacts on recreational and commercial fishing, spreading quickly, displacing native fish as well as eating their eggs and young. Many of these waters could easily be (and are) visited by British anglers fishing in the Netherlands that have purchased a VISPAS licence, a Dutch version of our own rod licence.

Emily Smith on research trip in Netherlands

In September last year, I travelled to the Netherlands and collected three of these species to establish how well they would last on damp angling equipment, and the effectiveness of different treatment methods to try and kill the species. These species were also found during a previous survey of European fishing lakes undertaken by the Angling Trust in 2016.  Replicating the typical behaviour of an angler, I placed these species in damp nets inside black plastic bags in the boot of my car and monitored their survival rate. All the species survived the 20-hour return journey from Holland to the UK. Further laboratory experiments revealed that these species could survive for several days out of water on angling nets, mirroring the findings for other invasive species, including goby eggs and killer shrimp (Anderson et al., 2015; Hirsch et al., 2016).

Tests in the laboratory showed invasive species could last several days out of water

So what can we do?

Whilst research has shown that invasive species can survive out of water, they have also set out something we can do about it. The Check Clean Dry approach outlines three quick and easy measures that can cause 99% mortality in some species (Anderson et al., 2015).

Implementing these simple measures into your routine only requires a little bit of effort and could greatly reduce the survival rate of invasive species, with potentially huge long-term environmental benefits. There is free e-learning available on the non-native species secretariat.

The Angling Trust is  working with other organisations to improve the management of INNS and encourage the uptake of good biosecurity procedures by all recreational users.

Invasive Species Week runs from Friday, 23rd March until Thursday, 29th March. For more information visit the non-native species secretariat, and follow #InvasivesWeek

Water Primrose (ludwigia grandiflora) on a Dutch lake

Emily’s post is funded as part of the London Natural Environment Research Council (NERC) Doctoral training partnership, with the Angling Trust fulfilling the role of an ‘industrial CASE partner’. In this arrangement Emily will gain work experience while undertaking her PhD. As part of her employment, Emily has been managing the Angling Trust’s ‘Alien Attack’ Environment Agency contract.











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