I
Ian Cloke
Guest
Holiday fishing and foreign diseases
Written By: E.A. Press Officer
Now that the summer holidays are upon us many anglers will be heading abroad on fishing expeditions. Whether it be to the Continent or to more exotic climes, some simple precautions need to be taken to ensure you do not bring back any alien fish diseases or parasites.
The reminder comes from Environment Agency Head of Fisheries Dafydd Evans.
"One of the potentially most-devastating parasites is Gyrodactylus salaris that attacks Atlantic salmon causing severe tissue damage often resulting in death, and can devastate stocks," explained Dafydd.
"The parasite is widespread in Norway, Sweden, Russia, Finland and Denmark, and reported in France, Germany, Spain and Portugal. In Norway populations of wild salmon collapsed in nearly 50 rivers as a result of the introduction of the microscopic parasite. The impact on angling and tourism has been considerable."
The G.salaris parasite is half a millimetre in size and virtually invisible to the naked eye. It attacks the skins and fins of juvenile salmon causing severe tissue damage often resulting in death. Although the parasite has not yet been found in British waters, tests have shown that our salmon would be killed by it. As the parasite has a direct life cycle and reproduces very rapidly, it is possible that even a single specimen imported by accident to a previously unaffected river would be capable of starting an epidemic in a very short time.
"Although the main threat is from imported diseased fish, and controls are in place to minimise this risk, the disease could be brought in by anglers and their equipment. The parasite is very hardy and can survive in wet or damp clothing and equipment for up to six days," continued Dafydd.
"If you are returning with clothing, boots, waders, bags, keep and landing nets, lines, reels, bait boats and other fishing tackle used on rivers abroad, as well as bait fish, you can help prevent the import of diseases and parasites in two simple ways.
You can thoroughly dry all clothing and gear for at least 48 hours in sunlight and temperatures above 20?C, or disinfect by immersing in seawater or a salt solution (3% + sodium chloride concentration) for a minimum of 10 minutes. All gear should then be thoroughly rinsed in tap water."
If you took your own boat, dinghy or canoe abroad on the fishing expedition you are advised to clean, disinfect and dry the vessel before arrival back in the UK. Marine vessels returning from abroad do not pose a risk as the parasite cannot survive in seawater, but consideration should be given to tenders or other boating equipment used on rivers.
"Native parasites and disease causing agents are a natural part of fish ecology," added Dafydd. "They co-exist with fish populations in a balance between fish, the disease and the water environment. The highest risk of causing an outbreak is from the introduction of a new disease to our rivers and lakes.
"The promotion of good practice in disease control is a significant component of the Environment Agency?s duty to maintain improve and develop fishing and fisheries. Many fisheries owners provide net dips containing iodophore washes for anglers to use when entering a site. Use them if you have recently returned from a foreign fishing trip."
Written By: E.A. Press Officer
Now that the summer holidays are upon us many anglers will be heading abroad on fishing expeditions. Whether it be to the Continent or to more exotic climes, some simple precautions need to be taken to ensure you do not bring back any alien fish diseases or parasites.
The reminder comes from Environment Agency Head of Fisheries Dafydd Evans.
"One of the potentially most-devastating parasites is Gyrodactylus salaris that attacks Atlantic salmon causing severe tissue damage often resulting in death, and can devastate stocks," explained Dafydd.
"The parasite is widespread in Norway, Sweden, Russia, Finland and Denmark, and reported in France, Germany, Spain and Portugal. In Norway populations of wild salmon collapsed in nearly 50 rivers as a result of the introduction of the microscopic parasite. The impact on angling and tourism has been considerable."
The G.salaris parasite is half a millimetre in size and virtually invisible to the naked eye. It attacks the skins and fins of juvenile salmon causing severe tissue damage often resulting in death. Although the parasite has not yet been found in British waters, tests have shown that our salmon would be killed by it. As the parasite has a direct life cycle and reproduces very rapidly, it is possible that even a single specimen imported by accident to a previously unaffected river would be capable of starting an epidemic in a very short time.
"Although the main threat is from imported diseased fish, and controls are in place to minimise this risk, the disease could be brought in by anglers and their equipment. The parasite is very hardy and can survive in wet or damp clothing and equipment for up to six days," continued Dafydd.
"If you are returning with clothing, boots, waders, bags, keep and landing nets, lines, reels, bait boats and other fishing tackle used on rivers abroad, as well as bait fish, you can help prevent the import of diseases and parasites in two simple ways.
You can thoroughly dry all clothing and gear for at least 48 hours in sunlight and temperatures above 20?C, or disinfect by immersing in seawater or a salt solution (3% + sodium chloride concentration) for a minimum of 10 minutes. All gear should then be thoroughly rinsed in tap water."
If you took your own boat, dinghy or canoe abroad on the fishing expedition you are advised to clean, disinfect and dry the vessel before arrival back in the UK. Marine vessels returning from abroad do not pose a risk as the parasite cannot survive in seawater, but consideration should be given to tenders or other boating equipment used on rivers.
"Native parasites and disease causing agents are a natural part of fish ecology," added Dafydd. "They co-exist with fish populations in a balance between fish, the disease and the water environment. The highest risk of causing an outbreak is from the introduction of a new disease to our rivers and lakes.
"The promotion of good practice in disease control is a significant component of the Environment Agency?s duty to maintain improve and develop fishing and fisheries. Many fisheries owners provide net dips containing iodophore washes for anglers to use when entering a site. Use them if you have recently returned from a foreign fishing trip."