Climate Change and Migratory Species BTO Research Report 414 Climate Change and Migratory Species Authors Robert A. Robinson1, Jennifer A. Learmonth2, Anthony M. Hutson3, Colin D. Macleod2, Tim H. Sparks4, David I. Leech1, Graham J. Pierce2, Mark M. Rehfisch1 & Humphrey Q.P. Crick1 A Report for Defra Research Contract CR0302 August 2005 1 British Trust for Ornithology, The Nunnery, Thetford, IP24 2PU 2 Department of Zoology, University of Aberdeen, Tillydrone Avenue, Aberdeen, AB24 2TZ 3 IUCN - SSC Chiroptera Specialist Group 4 Centre for Ecology & Hydrology, Monks Wood, Abbots Ripton, Huntingdon, Cambridgeshire, PE28 2LS British Trust for Ornithology, The Nunnery, Thetford, Norfolk, IP24 2PU Registered Charity No. 216652 CONTENTS Page No. List of Tables, Figures and Appendices .....................................................................................................7 EXECUTIVE SUMMARY .........................................................................................................................9 EXTENDED SUMMARY .........................................................................................................................13 1. INTRODUCTION ........................................................................................................................37 1.1. Aims and methods ..........................................................................................................38 1.2. Certainty in Climate Change Impacts ..........................................................................39 1.3. Biological Adaptation to Climate Change ....................................................................40 1.4. Climate Change and other threats ................................................................................41 2. LEGISLATORY FRAMEWORK ..............................................................................................43 2.1. Definition of a Migratory Species ..................................................................................43 2.2. Legislative Background ..................................................................................................44 2.3. Convention on the Conservation of Migratory Species ...............................................44 2.3.1. Bats .....................................................................................................................45 2.3.2. Marine Mammals ..............................................................................................46 2.3.3. Birds ...................................................................................................................47 2.3.4. Other Memoranda of Understanding .............................................................48 2.4. Species-based Instruments .............................................................................................49 2.5. Site-based Instruments ...................................................................................................50 2.6. National legislation .........................................................................................................51 3. SCENARIOS OF CLIMATE CHANGE ...................................................................................55 3.1 Introduction ....................................................................................................................55 3.2. Global Climate Change Modelling ................................................................................56 3.3. UK Climate Change Modelling .....................................................................................57 3.4. Projected Climate Change – Terrestrial Systems ........................................................58 3.4.1. Global .................................................................................................................58 3.4.2. Overseas Territories .........................................................................................59 3.4.3. United Kingdom ................................................................................................60 3.5. Projected Climate Change – Marine Systems ..............................................................60 3.5.1. Temperature ......................................................................................................60 3.5.2. Sea Levels ...........................................................................................................61 3.5.3. Ocean Circulation .............................................................................................61 3.5.4. Sea-ice Extent ....................................................................................................61 3.5.5. Changes in salinity ............................................................................................62 3.5.6. Storm frequency, Wind Speed and Wave Conditions ...................................62 4. CLIMATE IMPACTS ON MARINE MAMMALS ..................................................................71 4.1. Range & Distribution .....................................................................................................71 4.2. Migration .........................................................................................................................72 4.3. Potential effects and impacts of increasing temperature ............................................73 4.3.1. Potential Direct Effects .....................................................................................74 4.3.2. Indirect Effects ..................................................................................................74 4.4. Potential Impacts of Rising Sea-Levels .........................................................................77 4.5. Potential Effects of Changes in Ocean Currents ..........................................................77 4.6. Potential Effects of a Decrease in Sea Ice Cover ..........................................................78 4.6.1. Potential Direct Effects .....................................................................................78 4.6.2. Potential Indirect Effects ..................................................................................78 4.7. Potential Impacts of Changes in Salinity ......................................................................79 4.8. Potential Impacts and effects of Changes in Weather Patterns .................................80 1 4.8.1. Rainfall ...............................................................................................................80 4.8.2. Storm Frequency, Wind Speed and Wave Conditions ..................................80 4.8.3. Climate Patterns and Variability .....................................................................80 4.9. Summary of the potential effects of climate change on marine mammals ................81 4.9.1. Adaptation: Implications of climate change for the management and conservation of marine mammals ............................................................82 4.9.2. Knowledge gaps and future research ..............................................................82 5. CLIMATE IMPACTS ON MIGRATORY MARINE TURTLES ...........................................85 5.1. Direct effects and impacts of an increase in temperature ...........................................85 5.2. Direct impacts of a rise in sea level ...............................................................................85 5.3. Changes in ocean currents .............................................................................................86 5.4. Changes in storm frequency, wind speeds and wave conditions ................................86 5.5. Summary of the potential effects of climate change on marine turtles ......................86 5.5.1. Adaptation: Implications of climate change for the management and conservation of marine turtles ..................................................................86 5.5.2. Knowledge gaps and future research ..............................................................87 6. CLIMATE IMPACTS ON MARINE FISH, CEPHALOPODS AND PLANKTON .............89 6.1. Direct effects of an increase in temperature .................................................................89 6.2. Indirect effects and impacts of an increase in temperature ........................................90 6.3. Rise in sea level ...............................................................................................................91 6.4. Changes in ocean currents .............................................................................................91 6.5. Effects of a decrease in sea ice cover .............................................................................92 6.6. Changes in salinity ..........................................................................................................92 6.7. Increase in oceanic CO2 concentrations .......................................................................92 6.8. Changes in Weather Patterns ........................................................................................93 6.8.1. Rainfall ...............................................................................................................93 6.8.2. Storm Frequency, Wind Speed and Wave Conditions ..................................93 6.8.3. Changes in climate patterns/variability ..........................................................93 6.9. Summary of potential effects of climate change on marine species ...........................94