Durham E-Theses Anthropogenic factors aecting European river lamprey Lampetra uviatilis in the Humber River Basin, north-east England FOULDS, WILLIAM,LUKE How to cite: FOULDS, WILLIAM,LUKE (2013) Anthropogenic factors aecting European river lamprey Lampetra uviatilis in the Humber River Basin, north-east England, Durham theses, Durham University. Available at Durham E-Theses Online: http://etheses.dur.ac.uk/7750/ Use policy The full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-prot purposes provided that: • a full bibliographic reference is made to the original source • a link is made to the metadata record in Durham E-Theses • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders. Please consult the full Durham E-Theses policy for further details. Academic Support Oce, Durham University, University Oce, Old Elvet, Durham DH1 3HP e-mail: [email protected] Tel: +44 0191 334 6107 http://etheses.dur.ac.uk 2 UNIVERSITY OF DURHAM School of Biological and Biomedical Sciences Anthropogenic factors affecting European river lamprey Lampetra fluviatilis in the Humber River Basin, north-east England By William Luke Foulds BSc (Hons) Thesis submitted for the degree of Master of Science (by Research) 2013 ABSTRACT Anadromous lampreys have declined throughout the world due to damaging anthropogenic activities. This is particularly evident for the European river lamprey Lampetra fluviatilis, and studies in the Humber River Basin have shown that poor longitudinal connectivity (between their feeding and suitable spawning habitats) due to man-made barriers and their commercial exploitation for recreational angling bait, are potentially impacting upon this population. The objectives of this thesis were two-fold. Firstly, to evaluate the efficacy of technical, conventional fishways for upstream migrating river lamprey, as the effectiveness of these fishways to provide free passage for lamprey at man-made barriers in the Humber and elsewhere in Britain is unclear. Secondly, to reassess the level of exploitation in the tidal Ouse, Humber River Basin, and investigate both the scale and structure of the lamprey bait market in Britain and the knowledge and attitudes of key stakeholders within the market, which so far remain unknown. Passive Integrated Transponder telemetry revealed that two fishways of different technical designs, plain Denil and pool and weir, were extremely inefficient for river lamprey, with passage efficiencies of 0.0 and 5.0% and attraction efficiencies of 91.8 and 42.6%, respectively. Lamprey were significantly delayed, up to 150 days, at the Denil fishway and lamprey failed to pass despite re-entering fishways on up to 12 separate days. Analysis of catch data suggests that there has not been a decline in the river lamprey stock in the Ouse, although up until 2009 (inclusive) the exploitation level may have been at least twice (~20%) the level reported previously. Telephone interviews of angling wholesale supplier and tackle shop managers in Britain revealed that c.9 tonnes of river lamprey were supplied to tackle shops and anglers in Britain between 2011-2012. It also revealed that the majority of lamprey were sourced from The Netherlands and Estonia. The vast majority of tackle shop managers were unaware of which species of lamprey they sold, where they originated from and whether they were threatened, although most (77%) said there should be a ban on the capture and selling of lamprey in Britain if they were considered to be threatened. Conversely, supplier managers were generally more knowledgeable about the lamprey they sold but were more indecisive over a ban. i CONTENTS Abstract ........................................................................................................................ i Contents ...................................................................................................................... ii Declaration ................................................................................................................. iv Statement of copyright………………………………………………………………………..v Acknowledgements .................................................................................................... vi CHAPTER 1: General Introduction ............................................................................. 1 1.1. Decline of freshwater fishes ......................................................................... 1 1.1. Lamprey ecology .......................................................................................... 2 1.2. Lamprey conservation .................................................................................. 4 1.3. European river lamprey ecology ................................................................... 9 1.4. Status of river lamprey in Europe and Britain ...............................................12 1.5. Anthropogenic factors affecting river lamprey populations in the Humber, Britain and Europe………………………………………………………………….16 1.5.1. River regulation ....................................................................................16 1.5.2. Commercial exploitation .......................................................................22 1.5.3. Impingement and entrainment ..............................................................24 1.6. Summary and research direction .................................................................26 CHAPTER 2: Extreme inefficiency of two conventional, technical fishways used by European river lamprey .............................................................................................29 2.1. Abstract .......................................................................................................29 2.2. Introduction .................................................................................................30 2.3. Methods ......................................................................................................32 2.3.1. Study site .............................................................................................32 2.3.2. Fishways ..............................................................................................34 2.3.3. Lamprey tagging and PIT telemetry ......................................................36 ii 2.3.4. Flow measurements, environmental factors and analysis .....................38 2.4. Results ........................................................................................................40 2.4.1. Attraction and passage efficiency .........................................................40 2.4.2. Patterns of visitation .............................................................................43 2.4.3. Diel activity ...........................................................................................47 2.4.4. Flow measurements .............................................................................47 2.5. Discussion ...................................................................................................49 CHAPTER 3: A multifaceted investigation into the European river lamprey angling bait market in Britain: commercial catch and stakeholder attitudes ...................................55 3.1. Abstract .......................................................................................................55 3.2. Introduction .................................................................................................57 3.3. Methods ......................................................................................................61 3.3.1. Commercial catch data .........................................................................61 3.3.2. Telephone questionnaires: design and analysis ...................................63 3.4. Results ........................................................................................................70 3.4.1. Commercial catch in the tidal Ouse ......................................................70 3.4.2. Wholesale supplier telephone interview ................................................76 3.4.3. Tackle shop telephone questionnaire: Supplier A sampling frame ........79 3.4.4. Tackle shop telephone questionnaire: online directory sampling frame 92 3.5. Discussion ...................................................................................................93 3.5.1. Commercial lamprey fisheries in the tidal Ouse ....................................93 3.5.2. Scale and structure of the river lamprey angling bait market in Britain ..97 3.5.3. Knowledge and attitudes of stakeholders ........................................... 101 CHAPTER 4: General Discussion ............................................................................ 105 Appendices ............................................................................................................. 110 References .............................................................................................................. 118 iii DECLARATION I, William Luke Foulds, hereby declare that this thesis entitled: “Anthropogenic factors affecting European river lamprey Lampetra fluviatilis in the Humber river basin, north-east England” is, to the best of my knowledge, a presentation of my own original work and that no work done by any other person or group is included, except where