The club’s coarse lake’s sub group met on 14th November. We heard updates on the work at Petersfinger, Steeple Langford and the smaller lakes.
Petersfinger; Things have not settled with time, fish are continuing to die. Plants have been added and will be developing and helping things but water quality monitoring and fish health checks have shown that we still have problems. The lake bed silt is highly organic and is producing detectable levels of lethal toxins, ammonia and nitrite. Fish sampling has shown good gill health but with excessive mucus present and poor internal organ health. Winter months will see increased toxin levels as plants stop utilising the excess nutrients. Problems are greater In Clark’s Lake than in Hand’s. Although the levels of toxins do not generally reach the lethal levels experienced during mass fish kills in the early season their fluctuations alongside other variables such as PH(acidity/alkalinity), oxygen level and temperature cause ongoing stress to the stock and make them more vulnerable to the toxins produced when algal blooms crash overnight.
Examination of the options with various experts has led us to the conclusion that physical de-silting of the lakes would be prohibitively expensive and impractical on a site adjacent to an SSSI and SAC and within the flood zone. The costs of such an exercise would be many hundreds of thousands of pounds way beyond any reserve held by the club and not realistically recoverable from the membership over time.
An alternative plan has been developed and will be put to committee for approval. It is at a manageable cost and has every chance of recovering the fisheries to satisfactory condition for stock to be reassessed and established in the next season in Hand’s lake at least. At its simplest level of explanation it involves investment in a specific lake bed aeration system to reduce the anaerobic conditions at the silt surface layer and deeper where the toxins are being produced. Clark’s lake will receive a dosing of Siltex in the next few months which begins the process of managing the toxic silt but carries some biochemical risk, however this is reduced in Clark’s because the fish stock there is now very low.
Once approved this plan can be made available to members and anyone who wants a detailed explanation can have the chance of visiting the lakes and discussion with work group members.
We now expect both Petersfinger lakes to remain closed for the rest of this season.
Steeple Langford; We have had no fish kills at the lake this year but problems remain with algal conditions continuing to be dominant despite some weed growth in what is now clearer water. Tree work on two islands in the small lake remains to be completed but already the amount of leaf litter has been reduced and much more air can get to the lake. Floating islands have been built ,planted and parked in the shallows, underwater mesh cormorant refuges remain to be added for predator protection. These will over time reduce the nutrient load. Repair work and platform building is ongoing.
Sediment surveys and testing, water quality sampling with the test kit we now have will be undertaken this winter. Both lakes at Langford although they have not caused the same problems this year need to go through the same processes as Petersfinger to establish long term health.
A mark and recapture stock assessment is planned for this winter on the small, Pleasure lake, from this it will be determined whether fish need to be moved out of the small lake particularly bigger carp and mixed species stocked as necessary.
Work on the larger, White Bird lake will follow on when the smaller Pleasure Lake is completed but is likely to take several seasons to complete. All our plans and actions at Langford have to be checked with and confirmed by the owner which limits the freedom we have to make changes there.
Dandy’s Lake and Nightingale Lake have been fishing well with increased visits.. The work done at Dandy’s last season and earlier this year is showing results with improved water chemistry, established weed growth and good fish numbers showing.
Hayward’s Pond is now open, the water level is good and a working party will be arranged shortly to clear a number of swims for the coming winter fishing. This is an old fashioned “Mr Crabtree” style natural pond with mixed stock and fishes well in the winter months with thriving populations of crucian carp, perch, rudd, common carp and tench.
The Test Valley fishing organised has not been well used and alternative arrangements are being considered. The extra places at Witherington however are in demand and will continue for at least the rest of this season.
Steeple Langford Carp Census
It is now 2 months since the Langford Carp Census was set up and to date there has not been one submission using the online form.
Please use this facility to help the Club understand the numbers of carp in both Whitebird and the Pleasure lake, when you catch a carp please do the following:
Take a mat shot of both sides of the carp,
Record the weight.
Complete online submission form: View here
This project may be getting extended to other species in the future.
All records are confidential and are being used to help calculate the biomass of the lakes.