Ye gods, some fish have been reported from Wyesham on the day travel restrictions in Wales are lifted, Funny that. Their total for the season appears to be 52 fish including one of 27lbs making perhaps just a handful of springers for the whole river so far.
Also another fish from Redbrook 13lbs on a black Francis.
Still a good amount of fish holding on the lower beats over the weekend but they would not take anything.
Coedithiel report a total of 20 fish and Upper Bigswier 14, No detail however. Strange times but better late than never..
LATEST Seems some fish have gained access to the upper river at last. , Glanwye report a hen fish of 15lbs and and a 5lb fresh grilse on fly to Alistair Thompson today.
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Reckon this one qualifies as a springer. 40lbs plus That's some fish.
Wye Local Fishery Group (WLFG)
Fishing during hot, dry weather
July 2020
Advice to anglers
Atlantic salmon is a cold water species. During times of warm waters, salmon experience temperature-related stress or exhaustion, which can cause death. Research has shown that when the minimum water temperature stays above 20˚C, Atlantic salmon struggle to recover from stressful events, such as capture by fishermen, and can experience elevated rates of mortality.
Prolonged hot and dry weather poses a serious risk to all of our fish species, and it seems that drought is to be the new, and worrying, norm with more extreme weather patterns experienced more frequently. Salmon and trout are among our most vulnerable species and their protection in the face of a rapidly changing climate demands strong actions.
We have therefore provided this advisory note to help and support anglers decide whether fishing for vulnerable species during high summer temperatures can be done in a way that will minimise impact on valuable fish stocks.
Why is it important?
Prolonged warm and dry weather can affect fish both in rivers and still waters. Reduced water levels combined with high water temperatures reduce the amount of dissolved oxygen in the water. Low dissolved oxygen in a river or lake often means that it takes longer for fish to recover from being caught, and this is especially the case for the larger, harder fighting fish species. The combination of high-water temperature and low dissolved oxygen levels can also make fish more susceptible to disease parasite infections and predation, so they need particularly careful handling.
Different fish species need different amounts of oxygen but, in general, for most freshwater fish to thrive the dissolved oxygen needs to be:
• above 7 mg/L for coarse fish.
• above 9 mg/L for salmon and trout.
Temperature is also important, partly because dissolved oxygen and water temperature are closely linked (the higher the temperature, the lower the dissolved oxygen) but also in its own right. The following is a rule of thumb for temperature:
• for salmon and trout:
o below 20oc to minimise risk to survival;
o below 19oc to reduce risk of mortality after catch-and-release.
• For riverine coarse fish – mainly barbel and chub:
o Below 19oc to reduce risk of mortality after catch-and-release.
There is no single specific lower limit for dissolved oxygen level in a river because different fish species have differing oxygen requirements. The requirements also vary with temperature and whether fish are actively migrating or in the process of spawning. Some fish species are also able to acclimatise to low dissolved oxygen or may seek out areas of higher dissolved oxygen such as weir pools. Dissolved oxygen concentrations of less than 5 mg/L are likely to present a problem for most species that anglers normally fish for.
Dissolved oxygen levels may also be affected by the presence of algal blooms and aquatic weed growth which can significantly alter the level of dissolved oxygen levels within a water body. Algal blooms can result in high oxygen levels during daylight hours but then reduced levels of dissolved oxygen at night. Algal blooms can therefore place additional stress on fish species and angling should be avoided where significant algal blooms are observed to be present.
Different fish species can also tolerate a range of temperatures. However, the water temperature in rivers often exceeds 200C, with some rivers occasionally exceeding 250C. Still waters are likely to be several degrees warmer. At these temperatures, dissolved oxygen levels are likely to be low.
We know how damaging adverse temperature and dissolved oxygen can be in the Wye. During the drought of 1976, there was a mass mortality of hundreds of adult salmon when water temperatures peaked at 27.6oc and a mass dieback of Ranunculus caused localised deoxygenation.
What can anglers do to help?
Anglers can help protect valuable fish species and stocks during hot weather.
• You cannot easily check dissolved oxygen levels, but you can check the water temperature. River Wye temperature monitors provided by WUF in the link: . https://www.fishingpassport.co.uk/river-weather-conditions provide the temperatures in the upper river at Llanstephan and lower river at Redbrook. You can also use a hand-held thermometer to measure the temperature where you fish
If river water temperature exceeds19oC by 9am you may choose not to fish or target less sensitive species.
• If water temperatures are likely to have fallen overnight, consider fishing earlier in the morning. Keep an eye on the water temperature and be prepared to change your plans if it gets too high.
• Avoid targeting more sensitive and larger fish where water temperatures are likely to be in excess of 190C. Salmon, trout, grayling and large chub, barbel and pike can be particularly vulnerable to high water temperature and lowered dissolved oxygen levels.
• Above 180C handle fish with extreme care and fish appropriately (put away the spinning rod).
• For salmon, at water temperatures over 200C there is a greatly increased risk of mortality after release. There is a 3% chance of a fly caught fish dying due to being caught up to 180C, that becomes 10% at 200C, 20% at 210C, 40% at 220C, 80% at 230C. Spinner caught fish have a higher initial mortality (around 10%) that those caught on fly, but followed the same curve.
• Wye salmon start to die at around 270C, without being subject to angling pressure.
• For still water fisheries, please seek specific advice and guidance from the fishery owner or manager
• Minimise your use of ground-bait in all waters. As it decomposes, this can further reduce the amount of dissolved oxygen in the water.
• Handle all fish with care, using wet hands when holding and unhooking fish. Wherever possible, keep fish in the water while unhooking and release them as soon as they have recovered.
• If you plan on taking photos, try to take them with fish still in the water.
• Avoid using keep-nets for coarse fish. If you choose to use a keep-net, place it in deeper water, rather than parallel to the bank. Deeper, cooler water will hold more oxygen than shallow marginal water.
• Where possible, release fish into deeper, faster flowing water, where it is safe to do so. This will hold more dissolved oxygen and speed up their recovery.
• If fish need help to recover, hold them upright and with their head facing into the current. This will allow clear, oxygenated water to flow across their gills. You can also hold fish in a landing net in the river current until they show strong signs of movement. This may take several minutes, but it is best if the fish is fully recovered before being released.
In summary:
1. minimize angling duration (the time a fish is played and handled for hook removal);
2. minimize air exposure (15-20 sec) by removing hooks with the fish in water and photographing fish quickly;
3. Don't lay the fish on the bank under any circumstances;
4. use rubber nets void of knots that protect fish scales and mucous;
5. avoid angling during extremes in water temperature
And remember, if you see dead fish, fish in distress or gasping at the surface, please contact:
Natural Resources Wales on 03000 65 3000
or, in England: the
Environment Agency on 0800 80 70 60
and alert the fishery owner or angling club.
For further information see the Institute of Fisheries Management guides:
https://ifm.org.uk/managing-fisheries-in-prolonged-dry-weather-an-ifm-guide/
https://ifm.org.uk/wp-content/uploads/2020/06/Managing-Fisheries-in-Prolonged-Dry-Weather.pdf
Thank you for your support
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