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Title: The Use Of DNA Fingerprinting To Study The Population Dynamics Of Otters (Lutra Lutra) In Southern Britiain - A Feasibility Study
Author: K Coxon
Author: P Chanin
Author: J Dallas
Author: T Sykes
Author: Environment Agency
Document Type: Monograph
Annotation: Environment Agency Project ID:EAPRJOUT_484, Representation ID: 156, Object ID: 1823
Many factors have the potential to limit the recovery of otter (Lutra Z and a) populations.including road deaths, resource constraints such as prey, and-habitat availability and quality. Current practical conservation measures are based on surveys assessing-habitat potential, which is followed up by habitat improvements.. There is very little investigation of the requirements of the animals themselves due to lack of suitable survey techniques. The use of DNA fingerprinting of spraint provides a much needed survey tool to address the acknowledged need for research into the conservation needs and population biology of this species.. This new approach to surveying otters provides a means of addressing many of the targets of the UK Otter Biodiversity Action Plan.This was a collaborative project between the Environment Agency;the Universities of Exeter and Aberdeen, the Somerset Otter Group and the Devon and Hampshire Wildlife Trusts together with a large number of volunteers without whom the study would not have-been possible. The Report presents the findings of a one-year feasibility study into the.use of DNA fingerprinting to study the otter recovery-in southern Britain Four catchments were surveyed, one in Devon, two in Somerset and one in-Hampshire. The long-term objective of this. study is to characterise the population dynamics underlying the otter recovery in the UK over a period of four years, as a contribution to identifying the factors-limiting population expansion, to facilitate a more.focused, efficient and effective conservation effort. The objective of the feasibility study was to carry out a field test of the effectiveness of fingerprinting techniques in identifying individual otters and to develop a protocol for applying these techniques to large scale, repeatable projects. The Feasibility Study was an outstanding success. It answered many. of the questions asked, achieved its objectives and identified ways in which.the DNA fingerprinting technique needed improving. The Study has pr0vided.a unique insight into otter biology in southern England. A brief summary of achievements includes: l l l * l l Mobilisation of over 50 volunteers on four river catchments in Devon: Somerset and.Hampshire. Collection of over 600 spraint for analysis. Identification of 57 different otter DNA-profiles, including one that,was recorded23 times over a period of 19 months.Identification of breeding success on two of the catchments. Preliminary findings indicate that the-different population level on each cat and n-rent affects the distribution and ranges of individual-otters. 20% of samples analysed were successfully typed; the success rate of analysis of samples ranging from. 16 - 43% per month. iv i. Various problems were identified during the feasibility study and were either resolved during the course of the project or recommendations made for solutions to be addressed during a further three year study. The most notable problem w-as the discovery that two otters on the Itchen, assumed to be closely related, shared the same genetic profile at those loci analysed. This emphasised the need to check the genetic variability of the population to be surveyed by analysis of tissue samples prior to collection of spraint. DNA profiles of at least 10 otters are required to determine the suitability of a population for applying the technique to spraints. The duplication of one the DNA profiles within the Itchen population implies that the total number of otters identified, at least on the Itchen, is a minimum. This also means that the home ranges may be over estimated being based perhaps on more than one individual. There was no evidence of similar duplication within the Brue, Tone or Torridge populations. Continuation of the surveys would confirm the information gained so far on individual otters known home ranges and the estimated total number of otters within each catchment. However, preliminary findings indicate very different distributions between the Brue, Tone and Torridge. The Itchen results are difficult to interpret due to the duplication of DNA profiles. The four catchments are still being surveyed to maintain continuity in the data set with spraint samples stored at the University of Exeter using the protocol developed at the University of Aberdeen. Improvements are required with the DNA typing, for both the success rate of analysis and the number of loci developed for analysis to ensure individual otter identification. The 6 loci used for spraint analysis were not sufficiently variable to permit identification of individual otters on the Itchen where the genetic diversity of the population is low. The south west population appears to be on the borderline of variability required to successfully identify individuals. The number of loci required will depend on the levels of polymorphism they exhibit but a total of fifteen would be sufficient at the levels found at the loci already used. The level of genetic variability in the UK otter population is such that it is probably not possible to determine the relatedness of individual otters using existing. techniques. To be cost and resource effective the survey method requires the use of highly committed and motivated volunteers with individual training needs. A sampling protocol and proper equipment is necessary. Health and Safety is of paramount importance. Rapid analysis of spraint is required to enable a continuous review of any survey structure and allow the frequent feedback of results to the volunteers to maintain their support and enthusiasm. Addressing the problems identified in the Feasibility Study will require new resources and research effort. Improvements to the technique will not only facilitate a longer term study but should also permit its development as a reliable standard tool for monitoring otter populations. Recommendations are made within the report for a further three years study to build on the success of this feasibility study. V ABBREVIATIONS AONB ,a BAPccw CTAB ~. DNA EA EDTA ENFERGITC ITE ,: JNCC LEAP MGE NERC PCB PCR R and D SACSPA SOG. SRY SSSI VIU ..- Area of Outstanding Natural Beauty Biodiversity Action Plan I Countryside Council for Wales Cetyltrimethyl-ammonium Bromide .:. Deoxyribonucleic acid, Environment Agency Ethylene diamine tetra acetic acid . : English Nature. Fisheries, Ecology and Recreation .: Guanadium Iso-thio Cyanate Institute of TerrestrialEcology Joint Nature Conservancy Council Local Environment Agency Plan Molecular Genetics in .Ecology Natural Environment Research Council Polychlorinated biphenyl Polymerase Chain Reaction Research,and Development Special Area for Conservation Special Protection Area Somerset Otter Group Sex Related Chromosome Site of Special Scientific Interest Veterinary Investigation Unit vi ACKNOWLEDGEMENTS We are grateful to a large number of people who have contributed to this project and the preparation of the report. We would like to thank all members of the Project Board and Teg Jones and Libby Andrews from the Otter BAP Steering Group, for their guidance and technical input during the project and for their helpful comments on the earlier drafts of the report. Also, at the EA, our thanks go to the Southern Region and South West Regional staff for their help in preparing the maps within the report. At the Wildlife Trusts we thank the Otters and Rivers Project Officers and Somerset Otter Group for their help in providing historic data and co-ordination of volunteers. We would also like to thank Vic Simpson at the Veterinary Investigation Unit for his cooperation with supplying tissue samples and the results of the post mortem of the cub found on the Itchen. We are grateful to Kathy Sykes for preparing a simple introduction to DNA and fingerprinting and to the many riparian owners that gave permission and access to survey sites. Finally but most importantly a huge thank you goes to all the volunteers who have been out in all conditions collecting spraint. Without their help this project would not have been possible. vii CONTENTS. CONTENTS 1. ......................................................................................................................................................
Publisher: Environment Agency
Subject Keywords: Otter; Genetics
Extent: 146
Total file downloads: 5

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