Stuart Crofts sent me the following article regarding biosecurity for anglers, we should all take this issue very seriously.

Bio-Security for Anglers, Angling Clubs and Organisations – A way forward?


For many years now numerous waters have suffered from the effects of signal crayfish, himalayan balsam and mink. These are just three, high profile, organisms that come under the banner of ‘invasive non-native species’. The term invasive is important, this means they can seriously damage and modify our ecosystems. It is also interesting to note that 96 freshwater species, not native to the UK, have been recorded in the River Thames catchment. Admittedly not all these are damagingly invasive but it does make it one of the most highly invaded freshwater systems in the world. The Millennium Ecosystem Assessment Report (2005) notes that ‘the introduction of invasive non-native species is one of the major causes of species extinction in freshwater ecosystems’.  The report also notes that control or eradication of invasive non-native species, once established, is extremely difficult and costly. Prevention and early intervention are far more successful and cost-effective.

Since 2005 we have had new invasive non-native species turn up in the UK. In 2010 we added the killer Shrimp – Dikerogammarus villosus to the list. This species was originally identified at Grafham Water, Cambridgeshire in September 2010 and subsequently at Cardiff Bay and Eglwys Nunydd in South Wales. In March 2012, a further population was found at Barton Broad, in the Norfolk Broads. Importantly here, note the phrase ‘originally identified at Grafham Water’. This does not mean where it first appeared in the UK, that place may still be awaiting discovery, and no doubt there are other populations yet to be found. In October 2012 another Dikerogammarus species was discovered, this one is Dikerogammarus haemobaphes. It was found on the River Severn at Tewkesbury, the Bevere near Worcester, and also in two Worcestershire canals. Although related to the killer shrimp Dikerogammarus villosus, it is not yet clear what the impact of this species will be. However, it is being treated as a high impact species while further assessment is taking place.

In response to the Dikerogammarus villosus discovery the “Stop the Spread” campaign was initiated and publicised, this was based on the concept of “clean, check and dry” your clothing and equipment before you leave a watercourse in an attempt to stop the spread of aquatic invasive non-native species. This was and still is a great idea but I feel it is now time to seriously step up our efforts to protect our wonderful, but incredibly fragile, aquatic ecosystems. And, at the very least there should be a serious debate on the way forward.

The Threats

The first thing that we need to recognise and acknowledge are the vectors by which aquatic invasive non-native species can be spread, there are obviously very many of these but they can be split into two distinct groups. In one group we simply have no control at all such as natural wildlife movement (birds or animals moving from water to water), the general public on public rights of way, via water craft in navigable areas or other water sports on private waters. Also in this group are illegal deliberate movements of plants and animals (as what often happens with signal crayfish) or as a result of illegal activities; poaching and unauthorised canoeing are just two examples.

One we do want

However, in a second group we do have some control measures within our powers and it is this group I want to discuss. I am thinking particularly here of fishing activities on private land and waters whereby everyone has to follow “rules”. Before we pursue this further let’s look at how an ‘angler’ can become a vector for the spread of invasive non-native species and other aquatic viruses and diseases. The most obvious is via waders, wading boots, wading sticks, bank sticks, wellingtons, nets, bass bags and boat drogues. I am sure the list goes on; nonetheless all this kit is what actually spends much of the time in the water whilst the angler is fishing.  Now the Stop the Spread guidelines should cover this but it relies TOTALLY on the good will and diligence of the anglers. Moreover, the guidelines are aimed at those leaving a watercourse, not someone arriving. In addition, the guidelines will not protect against anglers fishing with natural or semi natural bait (as opposed to artificial baits like spinners, plugs and artificial flies and lures) that could harbour all sorts of damaging organisms. Not forgetting these baits are not just used by anglers on their hooks, where “ground baiting” is allowed, masses can often be thrown into the water to encourage fish to feed.

Control Measures

So, now we have established some possible methods anglers can, inadvertently, spread invasive non-native species let’s look at some control measures. The most extreme measure would be to simply ban anglers from the water, but this probably would not go down very well with the club members and I fear the finances would suffer!  More realistically a fishing club could request (or even insist) that an angler’s waders, wading boots, wellingtons, nets, bass bags and boat drogues etc. are only used on their water and not used in other places. In the case of bait fisheries, other restrictions could be put on the baits allowed and ground baiting methods employed. This already happens at some fisheries where you have to use nets provided by a fishery and restrictions are put on baits and methods that can be used. Obviously a fishery cannot supply wellingtons or waders to everyone. But, it can be insisted on that when an angler has arrived at a water these are totally bone dry, have been for several days and are free from mud (this can carry many viruses, diseases, plant fragments, seeds, or microscopic eggs etc.) and are visually checked. Add to this a requirement that all nets (not supplied by the fishery), waders, wading boots and wellingtons etc. that are not clean and dry are treated with a recommended disinfectant such “Virkon S”, on site, before fishing starts. The Stop the Spread guidelines must also be followed before the angler leaves. Virkon S is a wide spectrum multi-purpose disinfectant for use against viruses, some fungi, and bacteria. Obviously with Virkon, or other chemicals treatments, there would need to be some guidelines on safe usage and disposal methods. Such guidelines would need to be agreed with all the relevant statutory bodies (e.g. DEFRA, and the Environment Agency in England) and unfortunately Virkon it is not considered effective against killer shrimps. However, it has been shown that simple domestic hot water (above 43°C) can kill the shrimps. Okay, it needs fully testing but simply rinsing your wading boots (or wellingtons), the wader feet, gravel guards and nets etc. in nothing more than a bucket of hot water (say 45°C or more) after your fishing day and leaving them for 15 minutes bathing in the hot water before hanging them up to dry could be an additional simple method to help prevent killer shrimps from being unintentionally spread by anglers. This is already being encouraged in some areas and I believe it is a great idea.

Then there is the general behaviour of the club members (or paying day ticket visitors) to consider, they must be made responsible not only for their own bio-security but that of their guests they bring along. The same should go for fishing guides, gillies or instructors who should not only be responsible for their own bio-security but also that of their clients, make this a requirement not a request. Maybe all this is beyond the pale and some debate needs to take place to reach realistic working measures. But, while having these debates do not neglect the fact that you are not just trying to control the spread of the ‘known threats’ but also of those not yet identified. Think of it in terms of human disease control, when you know someone is infected it is easy to contain the situation but trying to control undiagnosed carriers is the challenging part. To add to the complex issues involved it will be necessary for fishing organisations and clubs to talk to each other, especially on rivers where you have different clubs controlling different parts of the same system.

To conclude, many other countries in the world take the protection of their native wildlife and bio-security very seriously. Regrettably, in the UK we do not, and that is unlikely to change via legislation any time soon. We (the anglers) need not only to keep our own house in order but be seen by the general public to be serious about the protection of our fragile freshwater ecosystems and lead by example. And, as I have said, at the very least start a debate and become much more proactive than reactive to the many threats from invasive non-native species. If you are reading this and you are on the committee of a fishing club or organisation why not think about a “Bio-Security Officer”. A Bio-Security Officers role would involve keeping up to date with the latest threats and the spread of invasive species. They would also need to review and update control measures to reflect the latest threats and best practice advice on bio security issues, obviously all based on good science.

Finally, if we are to continue to enjoy our wonderful sport on our precious waters into the future then clearly our attitude and culture will have to change to meet the growing threats, and think on this – if we do not do it, who will?

Stuart Crofts, November 2012

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