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Bean, C.W. (2003b). A standardised survey and monitoring protocol for the assessment of whitefish, Coregonus albula (L.) and C. lavaretus (L.), populations in the UK. Joint Nature Conservation Committee, Peterborough 43pp.

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Bean, C.W. (2003b). A standardised survey and monitoring protocol for the assessment of whitefish, Coregonus albula (L.) and C. lavaretus (L.), populations in the UK. Joint Nature Conservation Committee, Peterborough 43pp.
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  A standardised survey and monitoring protocol for theassessment of whitefish, Coregonus albula (L.)   and C.lavaretus (L.) , populations in the UK FINAL REPORTPrepared by:Dr Colin BeanScottish Natural HeritageAdvisory ServicesFreshwater Group January 2003  2 CONTENTSPageExecutive Summary41. Introduction6The Biology of whitefish within the UK72. Whitefish Distribution7 2.1 Global Distribution72.2 Distribution Within the British Isles72.2.1 C. albula 82.2.2 C. lavaretus 82.2.3 C. autumnalis 9 3. The Biology of the whitefish10 3.1 Genetic relationships within whitefish 103.2 Age and Growth103.2.1 C. albula 103.2.2 C. lavaretus 113.3 Spawning and Fecundity123.3.1 C. albula 123.3.2 C. lavaretus 133.4 Diet and Feeding143.4.1 C. albula 143.4.2 C. lavaretus 153.5 Parasites and Disease15 4. Conservation Status165. Exploitation of Natural Stocks17Sampling and Monitoring of Whitefish Populations176. Review of whitefish sampling methodologies 177. Description of selected sampling methods18 7.1 Gill netting187.2 Hydroacoustics21 8. Sampling strategy23 8.1 Spatial distribution of gill nets248.2 Temporal considerations248.2.1 Diel248.2.2Seasonal258.3 Hydroacoustic survey design258.3.1 Timing 258.3.2 Survey Coverage 26  3 9. Laboratory treatment of whitefish samples 26 9.1 Storage269.2 Somatic measurements289.3 Assessment of maturity and age289.4 Condition29 10. Estimation of whitefish density3011. Reporting3012. Assessment of Conservation Status3113. Costings3314. Acknowledgements3415. References34  4 EXECUTIVE SUMMARYBackground One of the special functions of the three country agencies (Scottish NaturalHeritage, Countryside Council for Wales, and English Nature) is theestablishment of common standards throughout Great Britain for themonitoring of nature conservation. The standards will apply to statutory sitesdesignated as Sites of Special Scientific Interest (SSSIs) and Areas of SpecialScientific Interest (ASSIs). They will also apply to areas designated as part of the Natura 2000 series, (Special Areas of Conservation (SACs) and SpecialProtection Areas (SPAs) under the EU Habitats Directive (92/43/EEC) and EUBirds Directive (79/409/EEC), together with Ramsar sites designated under the Convention on Wetlands of International Importance. A review of ecological and habitat needs of coregonids suggests that water quality, siltation of spawning areas and the introduction of alien or translocated species are the key features which dictate fish growth andrecruitment. Whitefish condition assessment Four strategies are proposed for assessment of conservation status of whitefish populations in SSSIs.  Abundance classification : The first approach classifies the density of whitefish in order to establish the relative condition of fish populations inlakes. Relatively few comparative data are available for this species to enablecomparisons to be made within individual SSSIs or with other waters. Although abundance may be used as an indicator of population status,the differing ecological status of each locality means that referencevalues must calculated which are unique for each waterbody. Only oncethis task has been completed can numerical density targets be set. Population demographic structure:  A further assessment can be made of the demographic structure of the population, i.e. the contribution of differentage classes to the population to demonstrate recruitment success. It issuggested that to achieve favourable condition both C. albula and C.lavaretus populations should have 90 % of individuals in the 0+/1+ ageclass.In addition to numerical targets for juvenile production, it is suggestedthat demographic structure of the population should reflect acontinuous pattern of recruitment. Maintenance of habitat quality: Both whitefish species are sensitive tochanges in water quality and habitat. Both species are associated with meso-oligotrophic lakes and spawning activity takes place on suitable spawninggravels within the lake itself. Changes in habitat quality through nutrient  5 enrichment, siltation, gravel exposure or loss of spawning substrateshould not have occurred to any degree if favourable condition is to berecorded. Presence of alien species:   The introduction of alien or translocated speciesparticularly those which predate directly on C. albula or  C. lavaretus , shouldbe viewed negatively. Sites containing established populations of speciessuch as ruffe should not be accorded favourable condition.Monitoring strategy Monitoring by a combination of targeted NORDIC style multi-mesh gill nettingand quantitative hydroacoustics is recommended as the approach to providean overview of the status of the whitefish populations within SSSI’s. Allsampling should be carried out over crepuscular and nocturnal periodsbetween the months of July and August.Other data required to interpret the status of whitefish populations include forklength, weight, condition, sex and state of maturity. Both scale samples andotoliths should be removed from each fish, although otolith reading isrecommended as the primary method for ageing both C. albula and C.lavaretus .Information relating to the nutrient status of each waterbody containingwhitefish is also required. If possible, this information should be viewedagainst long-term data sets.Prior to undertaking fisheries surveys there is a need to ensure theappropriate access permission and fishing rights have been obtained. Costings  Approximate costings for carrying out a monitoring survey for  C. albula or  C.lavaretus by external consultants are provided.
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