Annan Fishery Management Plan - RAFTS

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River Annan DSFB Fisheries Management Plan 2009 – 2014Since 1997 the RADSFB has mainly carried out minimum density electrofishingsurveys and a number of 3 run surveys that provide a more accurate density (ifrequired for consultancy work). The resources of the RADSFB do not allow 3 runsurveys to be carried out at every site. A limited number of sites are carried outannually to gain some record of long term trends in juvenile production for eachindividual stock. The 10 year trend (1997-2007) for minimum density figures ineach catchment are displayed below in Table 4.3.2. Greater numbers of surveysmay then be carried out on a particular river depending on what the Boardconsiders to be of greatest importance in each particular year.Table 5.3.2Ten year changes in abundance of juvenile salmonids in the Annan catchment (1997-2007)Tributary% change over ten yearsSalmonTroutMain stem minor Tribs +26.66% -38.31%Annan Water +45.41% +43.25%Dryfe -10.05% -70.95%Kinnel +18.45% -7.27%Moffat Water -8.85% -3.92%Milk +37.67% -61.48%Evan +97.46% +73.27%Kirtle -51.18% -40.69%Lochar -54.26% -29.46%Overall all sites on data base +13.80% -19.26%For example, with the beginning of the Sulwath Connections Habitat Project (seeSection 4.4.1) in 2007 it was decided to carry out a more comprehensive study ofthe Water of Milk and its main tributary, the Corrie Water where areas ofbankside fencing were to be constructed. The same areas will be assessed in theforthcoming years to discover if habitat improvement has led to increasedjuvenile production on these watercourses.This study involved the use of a method devised by Crozier & Kennedy (1994)and since modified that allows population densities to be calculated for timed(normally 5-10 minute) electrofishing surveys by carrying out a limited number of3 run sites and using statistical analysis to calibrate the juvenile abundancefigures from the timed sites into densities per 100m 2 in tandem with the 3 runsites completed. The advantage of this method is that timed surveys takesignificantly less time to complete and a greater number of sites can be sampledthus allowing estimates of juvenile production to be calculated on a wider scale.This method has been widely adopted throughout the UK using variations inprocedure to suit the purposes and staff levels of each organisation. It wasdecided to assess this method on the Water of Milk and Corrie Water.43
River Annan DSFB Fisheries Management Plan 2009 – 2014The database for this study was not as extensive as we would have liked due tothe poor summer weather and analysis showed that for the 2007 surveys thebest overall picture of the status of juvenile salmonids in the Milk and Corrie wasserved by the minimum density figures displayed above. In particular, the numberof 3 run sites carried out for calibration against timed sites was regarded as fartoo low. After consideration, it was decided that unless required for such asEnvironmental Impact Assessments or academic purposes, future monitoringschedules would be unlikely to feature time-consuming 3 run surveys.For the above reasons, it was decided that minimum density and timed catch perunit effort (CPUE) electrofishing surveys would be carried out in 2008. When aminimum density site was conducted, the time taken to complete the survey wasnoted to give a CPUE figure in addition to a minimum density estimate. Overtime, this will allow us to have a data set large enough to complete a CPUEgrading system similar to that compiled for minimum densities. This could be ofparticular use in areas where area based surveys are unsuitable, e.g. in channelstoo wide to survey efficiently using a single anode. Analysis of the 2008 data hasyet to be undertaken and this methodology will need further consideration as, forexample, varying levels of electrofishing efficiency between differing site channelwidths may need to be integrated into any grading system created. Theadvantage of the 2008 methodology is that no extra survey time was required togather CPUE data in addition to that produced for minimum densities.Action5.3.1.aDescriptionDecide on the best methodology for futuremonitoring programmesReactive orProactiveProactiveTimescaleCompleteend 20095.3.1.bContinue to monitor juvenile production in allcatchmentsProactive Ongoing5.3.1.c Ensure all staff are trained to SFCC standards Proactive Ongoing44
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Annan Fishery Management Plan - RAFTS

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