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Fish Catches for 2003Trout and SalmonCatches for both salmon and sea trout were amongst the lowest ever recorded on the Annan, although the brown trout catch was about the same. It was a harsh crash back to reality after the record catches of 2002. The total catch recorded by RAFIA was 438, 931 and 367 for salmon, sea trout & brown trout respectively. Much of the reason for this will have been the extreme conditions experienced throughout the summer and autumn. Indeed 2003 was the 4th driest year since records began (1968) and the driest year since 1974. During May and November the level of the river fell near to the all time lows ever recorded on the river. The chart below illustrates the differences in water flow as monthly means for 2002, 2003 and the long-term average.
It is important for anglers to remember however that an annual catch of salmon does not in itself provide a good guide to fish abundance as exceptional conditions, such as in the last two years, can cause huge a variation. Using catch figures is a very crude way of determining how healthy a fishery is due to a number of anglers who never make returns. Catch figures can therefore only be used for an assessment of trends in the fishery- e.g. run timing and the relative health of different stock components. The standard way to level out these extremes is to express figures as five or ten year averages. The next chart shows the trends of catches since RAFIA collated figures in 1981.
This chart shows that over all the salmon catch has remained relatively stable despite the bumper salmon catches of 2002 and the appalling catches of 2003. The sea trout slump of the mid 90s appeared to be over by the late 90s. The reduction in this stock over the last couple of years may be a warning for the future but it is too early to tell. What was very encouraging last year was the number of fish returned. Nearly 50% of all the salmon caught were put back along with 35% of the sea trout and 70% of all brown trout. Many of those fish would have been coloured but not that many years ago a large proportion of these would still have been killed. The anglers on the river are to be congratulated for these efforts – particularly in a year when chances were few and far between. HatcheryMost people will be aware that the hatchery project suffered a number of set backs last year. Only one Spring fish was donated and this fish turned out to be infertile (a rare but not unknown phenomena). The low water in October meant that very few fish ascended to the upper river where we could net them. A number of fish were netted out but most of these were back end fish and returned. As a result of the problems we experienced last year the whole concept has been re-thought. Without the use of Malachite (a fungicide that has just been banned), it is very difficult to keep broodstock alive for any length of time. If by catching broodstock and then confining them to a hatchery and we end up killing a proportion of them the hatchery will be counter productive. To avoid this, broodstock will be collected when they are as close to spawning as possible. Handling of the fish will be kept to an absolute minimum and stock densities of broodstock will be kept as low as possible. This year we are targeting the capture of around 50 hen fish using a variety of methods including seine netting, trapping and electrofishing. This will produce around 250,000 ova, which will be stocked into areas that are currently inaccessible to salmon. Selcoth Fisheries will carry most of the hatchery work out and the Annan DSFB will supervise the planting of the resultant fry. Currently the main areas that we are looking at stocking are the Upper Evan Water, two burns that enter the Moffat Water and the Upper Whamphray. Survey work.Habitat Surveys The Annan DSFB completed habitat surveys on the Dryfe Water, the Whamphray Water, the Corrie Water, the Duff Kinnel and side burns that enter the mainstem of the river between Moffat and Johnstone Bridge. The purpose of these surveys was to assess the suitability of the habitat found for young salmon and trout and to highlight any problems with habitat degradation or access issues. The photo below was taken on the Whamphray and is a good example of the sort of problem these surveys uncovered.
The surveys are very detailed allow the DSFB to make a qualitative judgement on the potential fish densities that would be found there if all things were equal. This is critically important for the hatchery project as it will allow us to stock the right amounts in the right areas and ensure that as much of the available habitat is occupied without wasting fish. Electrofishing surveysSeventy-six quantitative electrofishing surveys were carried out on the Annan’s tributaries together with a dozen qualitative fishing’s on the mainstem of the Annan between Millhouse Bridge and Annan. In general the results were good with the number of fry in particular very high. It would appear, as suspected, that the 2002 spawning season was very successful with fish accessing all parts of the river. There is however a concern about the low numbers of juvenile fish we found in the mainstem of the river, particularly from Williamworth Bridge downstream. The reasons for this are unclear. It is highly unlikely that lack of spawning adults is the problem as even in a dry year such as 2003 all of that part of the river is readily accessible. Further work will be carried out over this summer to try and determine the cause of this lack of fish. Likely candidates are high silt levels in spawning areas or pollution. It may be that the electrofishing was inefficient. Non-Migratory Fish SurveysThe Annan DSFB carried out a number of surveys that aimed to gather information on the status of the non-migratory population in 2003 (core funded by SNH). Two methods were used seine netting in the summer months and electrofishing in the autumn. The fish caught were aged and identified. Overall the grayling and the brown trout populations appeared to be high, although there did seem to be a weak year class amongst the grayling from 2002 spawning season. The spawning year for these fish in 2001 & 2003 however seemed very successful. Interestingly although a significant number of trout were caught in the 280mm to 340mm (11” – 13”), which is around the same size that some brown trout are stocked in the river no fish were found that came from a hatchery origin.
The trout in the picture above weighed about 5lb and was 6 years old.
The Grayling above was about 21/4lb and 3 years old. Both these fish were relatively young for there size and indicate speed at which fish can grow in the Annan. The chub population appeared to be more fragmented with very few age classes of fish being caught except for 2003 fry. These were extremely common and if their winter survival is good, it is likely that a very strong year class of chub will become apparent in anglers’ catches in a few years time. Chub are particularly interesting on the Annan as they represent one of the most northerly populations known in Europe. The conditions in the Annan are far from ideal for chub but they have successfully colonised much of the river. Successful spawning would however appear to be very infrequent and the population only manages to survive because individual chub can reach relatively old ages. It would not be unusual to find a fish over 20 years old. To ensure the continuation of there species in the river they probably only have to spawn successfully once every 5 – 10 years.
This chub weighed around 5lb and was over 10 years old As a by catch to this work, large numbers of salmon parr were caught in some sections. Although it would appear that there is a weakness in juvenile salmon populations in the lower river, everything appears to be fine from Lockerbie upstream. Some of these parr were of exceptional sizes with the largest being over 220mm (about 9”) long. Only one species was caught that was a surprise and that was a bream caught at Annan. This fish is a specialist of slow to very still silty waters and probably got washed down the river after escaping from Castle Loch, or Hightae Mill loch.
This bream was an out of place old-stager that was over 16 years of age. Lamprey surveysA nationwide survey of the presence of lampreys in Scotland was commissioned by SNH in 2003. The Annan took part in this work to try and find the distribution of these fish within the river. Sea lampreys were only found below the caul at Annan but the other two species (river and brook) were found in high numbers everywhere else in the river when the habitat was suitable.
The fish above is a mature river lamprey caught in the Kirtle near Eastriggs. Although locally common, lampreys may be endangered in many parts of the UK. WindfarmsA large number of windfarms have been proposed in the Annandale area. These have the potential to cause problems within the river, mainly during the construction phase through silt run of. The Annan DSFB has been commissioned by the major contractors to carryout pre-works surveys to assess the health of the rivers that could be potentially affected from these developments. The most sensitive areas have been highlighted and the construction planners will use this information when drawing up there final proposals. The watercourses that are likely to be most affected are the Ae, Kinnel, Evan, Milk, Mein and Kirtle. As long as the developers pay attention to detail there should not be any affect on the health of these tributaries. An area of mitigation that is being looked at is increasing the quality of the bogs in the upland and afforested areas that these wind farms will operate. Drainage for forestry and agricultural improvement has reduced the retention time of water in these areas. This will have had a large affect on the duration and severity of spates and low water periods on the river. Anything that can be done to address this situation should be welcomed. HLF BidIn 1999 the Annan DSFB started writing a plan for the further funding of habitat improvement works through a Heritage Lottery Fund (HLF) bid. Although the lottery board welcomed the plan, it was felt that unless we had further partners doing work that complemented our scheme it would be unlikely to progress. Since then a number of other organisations have picked up this idea and very shortly a bid will be sent in that will try to obtain around £3m of funding for environmental works in D & G. The Annan DSFB portion of that is around £500,000 over three years. This funding will not be available until 2005, but if successful it will mean a huge investment into the habitats on the river. Further informationFor further information on the work that the Annan DSFB carries out please contact N. Chisholm at The Annan DSFB, Fisheries Office, Annandale Est. St Ann’s, Lockerbie. DG11 1HQ (01576) 204078 or (07710) 331079 nick@annanfisheryboard.co.uk
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The low water periods will have been particularly problematical for the salmon. The drastic reduction in the sea trout numbers is probably of greater concern. There were a couple of periods of high water in May and July, which should have allowed a reasonable number of fish to run. It may have been that fishing conditions were so bad due to the low water that the sea trout in the river were particularly difficult to catch.
