Consultancy Report Client: Department for Environment, Food and Rural Affairs (DEFRA)

TRENDS IN CETACEAN STRANDINGS AROUND THE UK COASTLINE, CETACEAN AND MARINE TURTLE

POST-MORTEM INVESTIGATIONS 2005 (CONTRACT CRO 346)

Authors: R. C. Sabin, P. D. J. Chimonides, C. J. H. Spurrier & E. L. Evans-Jones (NHM) P. D. Jepson, R. Deaville (ZSL) R. J. Reid, I. A .P. Patterson (SAC) R. Penrose (MEM) R. Law (CEFAS) June 2006 Report No. ECM 5032/06

NHM Consulting Environment: Coastal & Marine Sector

Tel: +44 (0) 207 942 5636 The Natural History Museum, Cromwell Rd, London SW7 5BD, U.K.

CONTENTS General introduction to the joint report 4 Abstract 5 Part A: Trends in cetacean strandings around the UK coastline for the year 2005 7 Introduction 7 Results 8 Distribution of cetacean species 12 Balaenoptera acutorostrata – minke whale 12 Balaenoptera physalus – fin whale 12 Balaenoptera species indeterminate 12 Delphinus delphis – short-beaked common dolphin 13 Delphinus delphis/Stenella coeruleoalba - common/striped dolphin species indeterminate 15 Globicephala melas – long-finned pilot whale 15 Grampus griseus – Risso’s dolphin 15 Orcinus orca – killer whale 15 Lagenorhynchus acutus – white-sided dolphin 16 Lagenorhynchus albirostris – white beaked dolphin 16 Lagenorhynchus species indeterminate 16 Stenella coeruleoalba – striped dolphin 16 Tursiops truncatus – bottlenose dolphin 17 Unidentified dolphins 17 Phocoena phocoena – harbour porpoise 17 Physeter catodon – sperm whale 21 Mesoplodon bidens – Sowerby’s beaked whale 21 Ziphius cavirostris – Cuvier’s beaked whale 21 Unidentified beaked whale 22 Unidentified odontocetes and other cetaceans 22 Part B: UK cetacean and marine turtle post-mortem investigations for the year 2005 23 Introduction 23 Results 26 Causes of death 26 Infectious disease mortality 26 Entanglement in fishing gear (bycatch) 26 Physical trauma 27 Starvation 27 Live-stranding 28 Other causes of death 29 Investigations of relationships between environmental contaminants and health status 31

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Toxicology data from UK-stranded harbour porpoises 31 Gas embolism 31 Additional collaborative research activity 31 Scientific meetings attended 33 Additional report writing 33 Student theses 33 Publications for the year 2005 34 References 35 Appendices 37 Appendix 1: Distribution maps – UK cetacean strandings, 2005 37 Appendix 2: Lengths of stranded cetaceans by species, 2005 45

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GENERAL INTRODUCTION TO THE JOINT REPORT This report is based on research conducted under contract to the Department for Environment, Food and Rural Affairs (Defra) between 1st January and 31st December 2005. The following organisations were contracted or subcontracted under these agreements: Organisation The Natural History Museum (NHM) Cromwell Road South Kensington London SW7 5BD Tel: 020 7942 5155 Fax: 020 7942 5572 Zoological Society of London (ZSL) Regent’s Park London NW1 4RY Tel: 020 7449 6691 Fax: 020 7586 1457 Wildlife Unit SAC Veterinary Science Division (Inverness) Drummondhill Stratherrick Road Inverness IV2 4JZ Tel: 01463 243030 Fax: 01463 711103

Marine Environmental Monitoring (MEM) Penwalk, Llechryd Cardigan Ceredigion West Wales SA43 2PS The authors involved in the production of this report are as follows: R. C. Sabin, P. D. J. Chimonides, C. J. H. Spurrier and E. L. Evans-Jones (NHM) P. D. Jepson and R. Deaville (ZSL) R. J. Reid and I. A. P. Patterson (SAC) R. Penrose: Marine Environmental Monitoring (MEM) R. Law: Centre for Environment, Fisheries and Aquaculture Science (CEFAS)

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ABSTRACT In 2005, 700 UK-stranded cetaceans were reported. The previous five years (2000-2004) had seen progressively increasing numbers of UK-stranded cetaceans reported, predominantly owing to increasing winter strandings of short-beaked common dolphins (Delphinus delphis) and harbour porpoises (Phocoena phocoena) in south-west England and increased reports of harbour porpoise strandings in Wales. Cetacean strandings rates in other UK regions have remained more stable. Although post-mortem examinations have shown that strandings of common dolphins and harbour porpoises in south-west England in recent years were mainly cetaceans incidentally caught in commercial fishing nets (bycatch), factors such as changes in abundance and distribution of these species and increased reporting effort in south-west England may have played a role in the increasing number of strandings of both species reported. There were no unusual mass mortality events in cetaceans or marine turtles during 2005. The most common UK-stranded cetacean species in 2005 was the harbour porpoise of which 444 were recorded. The most common causes of mortality of the 124 UK-stranded harbour porpoises examined at post-mortem in 2005 were entanglement in fishing gear (bycatch) (n=24), starvation (n= 23), pneumonias due to combinations of parasitic, bacterial and fungal infections (n= 21) and attack from bottlenose dolphins (Tursiops truncatus) (n= 15). An additional two bycaught harbour porpoises were retrieved directly from fishing vessels for post-mortem examination. Most cases of fatal attack from bottlenose dolphins occurred in north-east Scotland and west Wales where porpoises have sympatric distributions with resident bottlenose dolphin populations. The annual number of stranded harbour porpoises killed by bottlenose dolphins has increased significantly in west Wales between 1999 and 2005. As in previous years, bycatch was the most common cause of death in UK-stranded short-beaked common dolphins accounting for 14 of the 25 (56%) examined in 2005. The majority of both short-beaked common dolphin and harbour porpoise bycatches typically stranded in south-west England (Cornwall and Devon) between January and April. Investigations of potential relationships between exposure to persistent environmental pollutants and health status in UK harbour porpoises continued in 2005 in collaboration with the Sea Mammal Research Unit (University of St Andrews) and the CEFAS Burnham Laboratory, Essex. A case-control study involving 257 individual harbour porpoises demonstrated statistically significant associations between elevated blubber polychlorinated biphenyls (PCBs) levels and infectious disease mortality (compared to controls that died of acute physical trauma) that was not confounded by a range of factors including age, sex, stranding location and two quantitative indices of nutritional status. The results of this study, published in 2005, were consistent with PCB-induced immunosuppression and associated increased risk of mortality due to infectious disease in harbour porpoises in UK and European waters. These analyses could form the basis of future risk assessments predicting the population-level impacts of immunosuppressive pollutants in cetacean populations of known size and PCB exposure. The first evidence of cetacean gas and fat embolism and associated acute and chronic lesions was published in 2003, including eight cases that stranded in the UK.

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The detailed pathology of these eight UK cases, plus an additional UK-stranded short-beaked common dolphin and a Risso’s dolphin (Grampus griseus), were published in 2005. There were no new cases of cetacean gas embolism diagnosed in UK-stranded cetaceans in 2005.

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Part A

TRENDS IN CETACEAN STRANDINGS AROUND THE COASTLINE OF THE UNITED KINGDOM FOR 2005

Introduction The Natural History Museum (NHM) has been recording and investigating incidents of cetacean strandings from around the coasts of the United Kingdom for more than 100 years. The work was formalised in 1913 when an agreement was created about the scientific study of stranded cetaceans, between the Board of Trade and the NHM (at that time called the British Museum (Natural History)) and was endorsed by the Crown. This agreement created the rights of the NHM to the legal acquisition of Royal Fishes, i.e. the Crown allowed the Museum first refusal of all Royal Fish for the purposes of furthering their scientific study. When debated in Parliament in 1970 it was decided to retain the classifications of 'Fishes Royal' for the benefit of Science. Since 1990, the work has been funded by the Department of Environment (DoE, later DETR), now the Department for Environment, Food and Rural Affairs (Defra). All strandings information recorded by the NHM since 1913 has been entered onto the National Cetacean Strandings database at the Museum, allowing the rapid extraction, detailed analysis and interpretation of the data. The NHM continues to submit data from the UK Cetacean Strandings Investigation Programme to the UK annual national report for ASCOBANS (Agreement on the Conservation of Small Cetaceans Of the Baltic And North Seas). Fourteen members of staff from the NHM were responsible for retrieving the carcasses of 36 cetaceans from locations around England for post-mortem analysis and examination in 2005. For the purposes of this report, the term ‘stranding’ includes those cetaceans washed ashore dead or alive, or those seen floating dead at sea. A small number of observed bycatch* records are processed by the NHM each year, representing those animals recovered from nets by fishermen, vessel-based official observers or other authorities. In 2005, the NHM assigned official reference numbers to three such reports, two from Scottish and one from English waters (see Appendix 2.13). Records of live sightings are passed on to those organisations that analyse such data. The success of the UK Cetacean Strandings Investigation Programme relies heavily upon the efforts of the countless numbers of individuals and organisations that make regular reports to the NHM. The NHM continues to be greatly helped in its work by its project partners Marine Environmental Monitoring (for strandings in Wales), Scottish Agricultural College Veterinary Science Division (for strandings in Scotland), and also by H. M. Coastguard, the Cornwall Wildlife Trust (for strandings in Cornwall), Brixham Seawatch, Devon Wildlife Trust and the National Marine Aquarium (for strandings in Devon), Durlston Marine Project and Hampshire Wildlife

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Trust (for strandings in Dorset and Hampshire), H. M. Coastguard, the Ulster Museum and the Irish Whale and Dolphin Group (for strandings in Northern Ireland) and the Environment Department, States of Jersey. Data from Jersey are discussed as a separate category, as regular reports have been formally received from the Environment Department since 2002. The location of Jersey provides an important insight into cetacean strandings along the south-western margin of the English Channel. Data from the rest of the Channel Islands are sporadic but are included when available. The NHM’s ‘UK Cetacean Strandings’ website can be viewed at the following address:

http://www.nhm.ac.uk/research-curation/projects/strandings/ The standardised strandings reporting form NHM 136 can also be downloaded from the Museum’s website: http://www.nhm.ac.uk/research-curation/projects/strandings/procedures.html

Results - 2005 The year 2005 saw a decrease in the number of reported UK cetacean strandings compared to 2003 and 2004 (see Table 3 and Figure A1), but is still the third-highest annual total since NHM records began. These reports comprised strandings of dead cetaceans, strandings of live cetaceans, reports of carcasses seen floating dead at sea and observed cetacean bycatch* (see Map1, Table 1 and Appendix 2.13). From 1st January to 31st December 2005, 700 reports were received, a decrease of approximately 12% on 2004. The main reduction was the number of short-beaked common dolphins reported – 94 in 2005 compared with 159 in 2004, a decrease of approximately 40%. Of the 28 reported live strandings, 2 were successfully returned to sea. The number of reported unidentified dolphins (too decomposed to identify to species) in 2005 was approximately 30% lower than 2004 (n=38 and n=55 respectively - see Table 3). The number of harbour porpoises reported in 2005 was slightly lower than 2004 (n=444 and n=472 respectively), a reduction of approximately 6%, but still represents the second-highest total recorded by the NHM.

Table 1: Report categories Stranded, dead cetaceans 641

Live-strandings 28

Observed cetacean bycatch* 3

Carcasses seen floating at sea 28TOTAL 700

Records for the year 2005 include details of at least 14 cetacean species:

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http://www.nhm.ac.uk/research-curation/projects/strandings/procedures.html

Table 2: Reported cetacean strandings etc. in the UK for 2005 by region and species

ENGLAND & ISLE OF MAN

WALES

SCOTLAND

NORTHERN

IRELAND

STATES OF

JERSEY

TOTAL

BALAENOPTERIDAE Minke whale 1 - 13 - - 14Fin whale 1 - - - - 1Unidentified rorqual 1 1 - - 2DELPHINIDAE Short-beaked common dolphin 76 8 10 - - 94Common/striped dolphin indet. - - 2 - - 2Long-finned pilot whale 5 1 13 - - 19Risso’s dolphin - - 13 - - 13Killer whale - - 2 - - 2White-sided dolphin 1 - 8 - - 9White-beaked dolphin 1 - 7 - - 8White-beaked/white-sided indet. 1 - - - - 1Striped dolphin 4 1 2 - - 7Bottlenose dolphin 2 2 3 - - 7Unidentified dolphins 23 1 13 1 - 38PHOCOENIDAE Harbour porpoise 211 109 121 3 - 444PHYSETERIDAE Sperm whale - - 5 - - 5ZIPHIIDAE Sowerby’s beaked whale - - 1 - - 1Cuvier’s beaked whale - - 3 - - 3Unidentified beaked whale - - 1 - - 1UNIDENTIFIED Unidentified toothed cetaceans 6 1 4 - 1 12Unidentified cetaceans (other) 9 2 5 1 - 17TOTALS 342 126 226 5 1 700

Figure A1. Total number of reported UK strandings etc. 1990 to 2005

1 4 4

1 9 1

4 1 8

3 2 03 6 6

2 6 5

3 4 4 3 4 83 6 9 3 8 6

4 2 0

5 4 9

6 5 5

7 9 9

7 0 0

7 7 4

0

1 0 0

2 0 0

3 0 0

4 0 0

5 0 0

6 0 0

7 0 0

8 0 0

9 0 0

1 9 9 0 1 9 9 1 1 9 9 2 1 9 9 3 1 9 9 4 1 9 9 5 1 9 9 6 1 9 9 7 1 9 9 8 1 9 9 9 2 0 0 0 2 0 0 1 2 0 0 2 2 0 0 3 2 0 0 4 2 0 0 5

Tota

ls

The total for the year 2005 shows a decrease when compared with UK records for previous years (see Figure A1 and Table 3):

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Table 3. Numbers of all cetacean species stranded around the UK, 2001 - 2005

2001

2002

2003

2004

2005

BALAENOPTERIDAE Minke whale 14 18 17 14 14 Sei whale 1 - - - - Fin whale - - - 7 1 Unidentified rorqual - - - 1 2 Humpback whale 2 - - 2 - DELPHINIDAE Short-beaked common dolphin 126 119 209 159 94 Common/striped dolphin indet. 3 7 3 8 2 Long-finned pilot whale 27 21 5 5 19 Risso’s dolphin 6 11 7 10 13 Killer whale 1 1 1 - 2 White-sided dolphin 4 4 12 5 9 White-beaked dolphin 14 7 5 9 8 White-beaked/white-sided indet. 2 - 1 1 1 Striped dolphin 14 9 12 6 7 Bottlenose dolphin 9 6 7 8 7 Unidentified dolphins 29 51 114 55 38 PHOCOENIDAE Harbour porpoise 259 347 321 472 444 PHYSETERIDAE Pygmy sperm whale - 1 - - - Sperm whale 6 4 8 3 5 ZIPHIIDAE Northern bottlenose whale 3 - 1 2 - Sowerby’s beaked whale 3 1 1 3 1 Cuvier’s beaked whale - 3 1 2 3 Unidentified beaked whale - - - - 1 Unidentified toothed cetaceans 4 18 24 16 12 Unidentified cetaceans (other) 22 27 25 11 17 TOTALS 549 655 774 799 700

Figure A2. Reported cetacean strandings etc. for Scotland compared with the rest of the UK, 2001 – 2005

413

530

626 636

474

136 125148 163

226

0

100

200

300

400

500

600

700

2001 2002 2003 2004 2005

Tota

ls

England, Wales, N. Ireland & Isle of Man Scotland

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Figure A2, shows the reported number of cetacean strandings for Scotland compared with the rest of the UK. Where the total number of reported strandings for the UK as a whole fell by 12%, in Scotland reported strandings increased by 38% compared to 2004, with at least 13 cetacean species represented. In recent years, the number of reports for Scotland has remained fairly consistent – between 130 and 165 from 1998 to 2004, with little variation in the number of species recorded (average 13 or 14 per year). The main area of increase in 2005 was seen in the number of reported harbour porpoise strandings, which rose by approximately 45% from 83 in 2004 to 121 (Table 2). In Wales, a slight decrease in reported strandings was observed (Table 2) – 126 in 2005 compared with 146 in 2004, a reduction of 13%. Average number of species represented in the Welsh data in recent years was from 5 to 7 (2005 = 5). The total number of strandings reported for England and the Isle of Man in 2005 is significantly lower than previous years (Table 2) - 342 compared with 481 in 2004, a decrease of approximately 28%. This decrease is predominately due to the reduction in the number of short-beaked common dolphins reported stranded around the English coast – 76 in 2005 compared with 147 in 2004, a reduction of approximately 48%. Numbers of reported harbour porpoise strandings also fell in 2005 – 211 compared with 258 in 2004, a reduction of 18%. Data for harbour porpoise and short-beaked common dolphin will be discussed in more detail later in this report. In Northern Ireland, 5 cetaceans were reported, with only 3 identified to species level (harbour porpoises - Table 2). Only one report was received from States of Jersey – a single unidentified toothed cetacean found stranded at St. Helier harbour in September 2005 (Table 2). The relative percentages of the annual UK strandings total from 2001 to 2005 represented by the number of reports from each region are expressed in table 4: Table 4. Number of reports received 2001-2005 expressed as percentages of UK total

UK total (100%) 549 655 776 799 700 Region

England (inc. Isle of Man and Channel Islands)

284 (51.7%) 382 (58.3%) 489 (63.0%) 481 (60.2%) 342 (48.8%)

Wales 124 (22.5%) 143 (21.8%) 132 (17.0%) 146 (18.2%) 126 (18.0%)Scotland 136 (24.7%) 125 (19.0%) 149 (19.2%) 163 (20.4%) 226 (32.2%)

Northern Ireland 5 (0.9%) 5 (0.7%) 6 (0.7%) 9 (1.1%) 5 (0.7%)

Year 2001 2002 2003 2004 2005

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Distribution of cetacean species - 2005

Balaenopteridae Minke whale or lesser rorqual (Balaenoptera acutorostrata) Fourteen stranded minke whales were reported around the UK in 2005, a figure consistent with previous years (see Map 2 and Tables 2 & 3). Of these, thirteen were reported stranded around the northern and western coasts of Scotland from June to December (see Appendix 2.1). A single stranding was recorded on the English coast near Seacroft, south of Skegness, Lincolnshire on 18th October 2005 (SW.2005/256). This was the carcass of a very decomposed male, 5.94 metres long. Sightings of minke whales are rare in the North Sea to the south of the Yorkshire coast (Reid et al, 2003; p. 16), but is it possible that the carcass of this animal may have floated for some considerable distance before washing ashore. The dates of stranding illustrated by the data broadly support field observations reported in the literature. Most sightings are made from May to September, with few records between October and April (Reid et al, 2003; p. 17). Twelve of the strandings recorded by the NHM in 2005 were reported from June to October. Fin whale (Balaenoptera physalus) A single fin whale stranding was reported to the NHM in 2005 (Map 2). On Friday 18th November, the Maritime and Coastguard Agency reported the carcass of a large whale seen floating in the Solent near Nab Tower (SW.2005/278). The carcass was floating with its ventral surface uppermost, was intact but bloated and described as bleeding from large visible gashes. On 19th November, the carcass was found beached on a sandbank at Seagrove Bay, Isle of Wight, Hampshire (Appendix 2.2). Examination determined the sex as male and its length was confirmed as 13.41 metres. Length at birth for this species is 6 to 6.5 metres with a maximum length in the Northern Hemisphere of 24 metres (Jefferson et al, 1993; p. 53). The temporal distribution of these strandings is consistent with sightings of fin whales made around the British Isles, which occur mainly between June and December (Evans, 1992). Unidentified rorqual (Balaenoptera sp.) Two reports of unidentified baleen whales were sent to the NHM in 2005 (Map 2). The first report was made by Rod Penrose, Marine Environmental Monitoring and strandings co-ordinator for Wales. On 3rd February 2005, a whale 6.1 metres long was found alive and entangled in fishing gear approximately 1.5 miles off Llandudno, Gwynedd (SW.2005/26a). Operatives from the Royal Society for the Prevention of Cruelty to Animals and the Royal National Lifeboat Institution (Llandudno) managed to remove much of the trailing gear, allowing the animal to swim away. A positive

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identification of species was not made, although it was thought to be either a minke or small fin whale (Penrose, 2006; p. 12). The second report was made on 11th August 2005 by Liverpool Coastguard. The carcass of a very decomposed whale approximately 6.5 metres long was found on a sandbank near Formby Channel, Merseyside (SW.2005/206). The carcass was too decomposed to be identified, although some throat grooves and baleen plates were visible.

Delphinidae Short-beaked common dolphin (Delphinus delphis) In 2005, 94 short-beaked common dolphin strandings were reported to the NHM (Tables 2 & 3 and Map 3). This represents a reduction of approximately 40% compared with 2004 (n=159). Figure A3, shows the breakdown of numbers by month and region for 2005; the majority of short-beaked common dolphins reported in 2005 were found stranded around the south west of England (Cornwall including the Isles of Scilly (n=43; 2004 = 78), Devon (n=11; 2004 = 53) and Dorset (n=11; 2004 = 10). As the 2005 data show, records for Cornwall were down by approximately 44% whilst in Devon records were down by approximately 79%. There is no evidence to suggest that reporting effort for the south west of England was reduced in 2005. Data from recent years (Figure A4) show that from December, the number of reported short-beaked common dolphin strandings in the UK increase. Strandings usually peak from January to March with a dip in February, then reduce gradually into April/May. This pattern is driven by the predominance of stranding events of this species in the south west of England. Figure A3 shows a continuation of this pattern for 2005. Outside Cornwall, Devon and Dorset, the only other English counties where strandings of short-beaked common dolphins were recorded in 2005 were Hampshire (January, n=2), West Sussex (March, n=1), and Lincolnshire (July, n=2). Six carcasses were also found, floating in the English Channel at positions 49°32'N 04°20'W, 49°36'N 04°16'W, 49°37'N 04°21'W, 49°37'N 04°15'W, 49°36'N 04°45'W and 50°00'N 04°15'W, and collected by the Greenpeace vessel Esperanza from 22nd February to 16th March 2005. In 2005, there were 8 short-beaked common dolphin strandings recorded in Wales and 10 in Scotland (Table 2). The Welsh strandings occurred in January (n=3), June (n=3), October (n=1) and November (n=1). Scottish strandings were recorded in January (n=3), February (n=3) and one each month for April, May June and December.

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Figure A3. Strandings of short-beaked common dolphin by month for 2005

0

5

10

15

20

25

30

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Cornwall Devon Dorset Rest of England Wales Scotland

Figure A4. Cumulative monthly totals of short-beaked common dolphins stranded, UK,1998-2005

0

50

100

150

200

250

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov DecMonth

Cou

nt

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Short-beaked common dolphin / striped dolphin indeterminate (Delphinus delphis / Stenella coeruleoalba) In 2005, 2 strandings were recorded as short-beaked common/striped dolphin indeterminate, SW.2005/32d and SW.2005/238b, both at Strathclyde, Scotland in February and September respectively (Tables 2 & 3, Map 8). Numbers of these records vary from year to year depending upon the condition and accessibility of specimens. In terms of general body size and shape, short-beaked common and striped dolphins are quite similar. Once decomposition or scavenging has destroyed identifiable external characteristics, distinguishing between the two species can be difficult. Fortunately, the short-beaked common dolphin has two well-defined palatal grooves on the ventral surface of the rostrum that are absent in the striped dolphin. These can usually be identified through touch, by applying gentle pressure to the roof of the mouth. Long-finned pilot whale (Globicephala melas) Nineteen long-finned pilot whales were recorded in 2005, the highest total since 2002 (Tables 2 & 3, Map 4, Appendix 2.3). Numbers of strandings of these animals vary from year to year. The distribution of long-finned pilot whales reported in 2005 is comparable with that of recent years, being predominantly along the western coasts of Britain from Orkney and the Western Isles to south west England (see Appendix 2.3). The distribution data for 2005 accord with the historic sightings data for this species in UK waters (see Evans, 1995). Records were received each month for this species in 2005 (excluding May and December), with six of the strandings occurring in July. Risso’s dolphin (Grampus griseus) Thirteen reports were received for Risso’s dolphin in 2005 (Tables 2 & 3, Map 4). This figure is comparable with those of recent years, although numbers of strandings do vary. All of the reports came from Scotland (see Appendix 2.4). The strandings distribution data are consistent with sightings data for the UK (Reid et al, 2003). The range of lengths for adults of this species is 2.8 to 3.3 metres, with neonatal length of 1.2 to 1.5 metres. Eight of the 12 specimens measured were of adult length. NHM data for 2005 show Risso’s dolphins present in UK waters through much of the year, a finding consistent with recent years. Killer whale (Orcinus orca) Only two reports of killer whale strandings were made to the NHM in 2005, both from Scotland (Tables 2 & 3, Map 4). On 15th July, a female killer whale measuring 6 metres in length was found stranded east of Unst in the Shetland Islands (SW.2005/188a). A second whale 2.49 metres in length stranded at Stoneybridge, south Uist in the Western Isles on 24th December (SW.2005/290c).

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White-sided dolphin (Lagenorhynchus acutus) Nine records were received for this species in 2005, compared with 5 in 2004 (Tables 2 & 3). Map 5 shows the distribution of white-sided dolphin strandings for 2005. Eight of the strandings occurred around the coasts of Scotland from March to November. A single stranding took place on the North Sea coast of England at Stubborn Sand, Heacham, Norfolk on 15th August 2005 (Appendix 2.5). Sightings and strandings of this species are uncommon in the southern half of the North Sea. The range of lengths given for adult white-sided dolphins is 2.0 to 2.8 metres (Evans, 1995). Of the 7 animals whose lengths were recorded, all were of adult length (Appendix 2.5). White-beaked dolphin (Lagenorhynchus albirostris) Eight records were received for this species in 2005, consistent with data for previous years (Tables 2 & 3). Map 5 shows the distribution of strandings for 2005, with 7 records received from the northern and eastern coasts of Scotland and 1 from the North Yorkshire coast (Appendix 2.6). This distribution is comparable with data from previous years and supports recent sightings data (Reid et al, 2003; p. 45). The range of lengths for adult white-beaked dolphins is 2.5 to 2.7 metres, with neonatal length of 1.2 to 1.6 metres (Evans, 1995; p.17). Four of the eight animals whose lengths were recorded were of neonatal length with the remainder ranging from 2.0 to 2.49 metres long. White sided / white beaked dolphin species indeterminate A single record was received in 2005 – a very decomposed dolphin, genus Lagenorhynchus found at Thornham Point, Norfolk, 10th December 2005 (SW.2005/287e; Map 5). Species identification could not be confirmed. Distribution data cannot be used to aid identification, as both white-sided and white-beaked dolphins are found in the North Sea. Sightings of white-beaked dolphins are more common in this region (Reid et al, 2003; p. 45). Striped or euphrosyne dolphin (Stenella coeruleoalba) In 2005, 7 striped dolphins were reported to the NHM (Tables 2 & 3), compared with 6 in 2004. Two of these were from Scotland, 1 from Wales and 4 from England (see Appendix 2.7). The strandings occurred from January to October. The distribution of striped dolphin strandings for 2005 can be seen in Map 5, and is similar to those recorded in recent years. Data held by the NHM show that most strandings of this species occur along the western coasts of the UK, from Shetland to Cornwall. Live sightings of striped dolphins in UK waters are classed as rare, with the species reaching the limits of its

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northern distribution at approximately 50° (Reid et al, 2003; p. 39). Sightings of this species in coastal UK waters mainly occur between July and December. The range of lengths given for adult striped dolphins is 1.95 to 2.4 metres and 1.0 metre for newborn animals (Evans, 1995; p.21). Using these criteria, 6 of the 7 animals that stranded in 2005 were below adult length (Appendix 2.7). Bottlenose dolphin (Tursiops truncatus) In 2005, 7 bottlenose dolphins were reported to the NHM (Tables 2 & 3), a figure consistent with those of previous years. Distribution of strandings ranged from the east coast of Scotland to south west England (Map 5 and Appendix 2.8). As with previous years, the strandings occurred from June to December 2005. The sightings data for the bottlenose dolphin outlined by Reid et al (2003; p. 37) are generally supported by the NHM’s strandings data. The maximum length given for this species in the eastern North Atlantic is 3.81 metres for males and 3.50 metres for females (Perrin and Reilly, 1984). Neonatal length is given as 0.98 to 1.30 metres (Evans, 1995). Unidentified dolphins There were 38 unidentified dolphins reported to the NHM in 2005, a decrease of approximately 30% compared to 2004 (n = 55; Tables 2 & 3). These reports relate to carcasses too decomposed, incomplete or inaccessible for examination and retrieval. Half of these reports relate to carcasses washed up around southwest England (Cornwall n=14, Devon n=3 and Dorset n=2) from January to April and September to December 2005 (Map 8). As with 2004, 12 of the unidentified dolphins reported in 2005 were from the Western Isles of Scotland (January to April, August and December). The remainder of the records were single occurrences from Antrim, Lothian, Swansea, Redcar, Norfolk, Suffolk and Essex. Harbour porpoise (Phocoena phocoena) In 2005, 444 strandings of harbour porpoise were reported to the NHM (Map 6, Table 2 & Figure A6), a decrease of 28 compared with 2004 (n=472). However, this total is still significantly higher than previous years and represents the second-highest total on record. Since 1993, annual numbers of reported harbour porpoise strandings have steadily increased (Table 3), making them the most common cetacean species to strand in UK waters. In recent years, harbour porpoises have represented approximately half of all cetaceans reported annually, but in 2005, this proportion rose to 63.42% (2004 = 59.07%). In England, 211 animals were recorded for 2005 whilst for Scotland the total was 121. There were 109 porpoise strandings recorded in Wales and 3 in Northern Ireland (Figure A7; Map 6).

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In 2004, increased levels of porpoise strandings were reported in all areas used to analyse annual data. The area that saw the largest increase in 2004 was Cornwall, where 90 porpoises were reported in the period January to April (compared with only 22 in the same period for 2003). In 2005, only 17 porpoise strandings were reported in Cornwall for the period January to April, and 38 for the whole year (Table 5; Figure A7). Porpoise strandings for the rest of England saw an increase of 30% compared with 2004, with peaks in March/April 2005. The main distribution of reported porpoise strandings around England (outside the south west) was as follows: N & E Yorkshire (n=27), Kent (n=20), Norfolk (n=19), Merseyside (n=16), Lincolnshire (n=12), Cumbria (n=10), Northumberland (n=9). Table 5. Monthly totals - harbour porpoise strandings 2005, with data for 2004 shown in blue Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Total

9 1 5 2 0 1 1 4 3 4 4 4 38Cornwall 48 21 13 8 4 3 1 1 0 3 1 11 114

3 4 1 0 0 0 1 1 1 1 0 0 12Devon 2 8 0 1 0 2 0 1 2 3 2 0 217 8 38 29 14 13 12 17 7 8 4 5 161Rest of

England 3 12 12 14 15 14 22 4 12 10 5 0 1235 4 6 2 11 23 17 11 14 9 3 4 109Wales 3 2 5 8 9 28 11 14 12 26 3 5 1265 11 21 18 15 12 12 7 6 6 5 3 121Scotland 5 10 7 15 8 9 8 5 4 5 4 3 830 1 0 0 0 1 1 0 0 0 0 0 3N. Ireland 0 0 1 1 0 3 0 0 0 0 0 0 5

29 29 71 51 40 50 44 40 30 28 16 16 444Total 61 53 38 47 36 59 42 25 30 47 15 19 472

In Scotland, reported harbour porpoise strandings rose by approximately 45% from 83 in 2004 to 121 in 2005 (Tables 2 & 5). Most of these reports were received between February and July, with a peak from March to May (Table 6). The harbour porpoise is consistently the species most commonly reported stranded in Scotland, usually accounting for approximately 50% of reports (2005 = approx. 53%). Table 6. Distribution of Scottish harbour porpoise strandings by month, 2005 Harbour porpoise TotalNumber 5 11 21 18 15 12 12 7 6 6 5 3 121 Month Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Reported harbour porpoise strandings in Wales were down by approximately 13% in 2005 to 109, compared with 126 in 2004. Most records were received from May to October with a peak in June/July (Table 5). In Northern Ireland, 3 harbour porpoises were reported in February, June and July 2005 from Donaghadee and Swinley Bay, Co. Down, and Castle Rock beach, Co. Antrim respectively. The annual summer peak in strandings of this species noted by Muir et al. (1999), thought to be associated with the peak months for parturition, is most visible for Wales, but is less apparent for the rest of the UK where strandings peak slightly earlier (England and Scotland = March/April).

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Figure A6. Total numbers of reported UK cetacean strandings, 1990 – 2005, compared with annual numbers of harbour porpoise.

1 4 4

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Figure A8, shows the number of harbour porpoise stranded by month from 1998 to 2005. June and July are shown as the peak months for strandings, with a smaller peak in March and April: Figure A8. Cumulative monthly totals of harbour porpoise stranded in the UK, 1998-2005

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The range of lengths given for adult harbour porpoise are 1.35 to 1.80 metres, and 0.67 to 0.90 metres for newborn animals (Evans, 1995; p.21). The length data for 2005 in Figure A9 show the presence of harbour porpoise in the range 0.5 to 0.9 metres from February through to September, with a peak occurring between June and August. As with previous years, these data show the summer months as the peak time for parturition in this species in the UK.

Physeteridae and Ziphiidae Sperm whale (Physeter catodon) In 2005, 5 sperm whale strandings were reported to the NHM compared with 3 in 2004 (Tables 2 & 3). All of the strandings were from Scotland (Map 7), from Orkney to Highland and the Western Isles (April to August; Appendix 2.9). The range of lengths given for adult sperm whales is approximately 8.3 to 11.00 metres for females and 11.0 to 16.0 metres for males (Evans, 1995, p.15; Whitehead, 2002, p. 1165). Using these criteria and given the lengths recorded for 2 of the 2005 specimens, they may be classified as physically mature males (Appendix 2.9). Sowerby’s beaked whale (Mesoplodon bidens) Only one report of a stranded Sowerby’s beaked whales was received in 2005 compared with 3 in 2004 (Tables 2 & 3). The animal, a male, 4.7 metres long, was found stranded on Peterhead beach, Grampian on 22nd January 2005 (SW.2005/18f; Appendix 2.10). Strandings and sightings of Sowerby’s beaked whales are usually recorded along the north and east coasts of Scotland (Map 7). Eight of the twelve strandings reported since 2000 have been female, with strandings occurring primarily in the latter half of the year (June to September). Sowerby’s beaked whales are one of the less-common species occurring in UK waters, and are occasionally absent from NHM annual strandings data. Cuvier’s beaked whale (Ziphius cavirostris) Three reports were received for this species in 2005 compared with 2 in 2004 (Tables 2 & 3). All 3 strandings were from the coasts of Scotland (Map 7 & Appendix 2.11). Cuvier’s beaked whale is one of the less-common species occurring in UK waters, and is often absent from NHM annual strandings data. In the past 16 years, strandings have been recorded on the north and west coasts of Scotland, the west coast of Wales, the east and southwest coasts of England. Records since 2000 show strandings of this species occurring throughout the year.

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Unidentified beaked whale (family Ziphiidae) On the 4th June 2005, an unidentified beaked whale carcass was reported beached at Aird a'Mhorain, North Uist, Western Isles (SW.2005/142c; Map 7). Apart from its determination as a beaked whale, no other details are available for this stranding. Unidentified odontocetes and other cetaceans In 2005, the NHM received 12 reports of unidentified toothed cetaceans (odontocetes) from around the UK, and a further 17 reports of carcasses not identified as toothed or baleen whales (Map 8). It is often difficult to identify such carcasses owing to their inaccessibility, incompleteness or to their advanced state of decomposition.

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Part B

UK Cetacean and Marine Turtle Post-mortem Investigations 2005

Post-mortem investigations of UK marine mammal strandings have been co-ordinated in England and Wales by the Institute of Zoology (IoZ) at the Zoological Society of London since 1990 and in Scotland by the Scottish Agricultural College in Inverness (SAC) since 1992. More recently, marine turtle examinations have been included in the remit. Both IoZ and SAC liaise closely with the Natural History Museum, London (NHM). Tissue samples collected from post-mortem examinations of UK-stranded marine mammals and turtles are archived by IoZ, SAC and NHM. The Poseidon central strandings database is held jointly by IoZ and SAC and stores pathological and other data derived from the post-mortem investigations of UK-stranded marine mammals. Most of the data currently held in the Poseidon database was generated under contract to Defra, although some data were generated independently by research collaborations with non-Defra-funded individuals or organisations. During 2005, 173 stranded or bycaught cetacean carcasses and three marine turtle carcass were examined at post-mortem in the UK (Table A). Of these, 76 carcasses were examined in Scotland (Table B), 68 were examined in England (Table C) and 32 were examined in Wales (Table D). The number of cetacean post-mortem examinations conducted in 2005 is comparable with the numbers conducted in previous years (between 2000 and 2004, an average of 178 stranded Cetacea post mortems/year were conducted). Table A: UK Cetacean and Marine Turtle Post-mortem Investigations during 2005

Species Number Harbour porpoise (Phocoena phocoena) 126 Short-beaked common dolphin (Delphinus delphis) 25 Striped dolphin (Stenella coeruleoalba) 5 White beaked dolphin (Lagenorhynchus albirostris) 5 Atlantic white-sided dolphin (Lagenorhynchus acutus) 5 Bottlenose dolphin (Tursiops truncatus) 2 Risso’s dolphin (Grampus griseus) 2 Long-finned pilot whale (Globicephala melas) 2 Minke whale (Balaenoptera acutorostrata) 1 Leatherback turtle (Dermochelys coriacea) 2 Loggerhead turtle (Caretta caretta) 1

Total 176

* Of the 126 harbour porpoises reported here, two were carcasses retrieved directly from fishing vessels.

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Table B: Post-mortem Investigations conducted in Scotland during 2005

Species Number Harbour porpoise (Phocoena phocoena) 56 Short-beaked common dolphin (Delphinus delphis) 6 Atlantic white-sided dolphin (Lagenorhynchus acutus) 4 White beaked dolphin (Lagenorhynchus albirostris) 4 Risso’s dolphin (Grampus griseus) 2 Striped dolphin (Stenella coeruleoalba) 1 Long-finned pilot whale (Globicephala melas) 1 Minke whale (Balaenoptera acutorostrata) 1 Leatherback turtle (Dermochelys coriacea) 1 Total 76

* Of the 56 harbour porpoises reported here, two were carcasses retrieved directly from fishing vessels.

Table C: Post-mortem Investigations conducted in England during 2005

Species Number

Harbour porpoise (Phocoena phocoena) 43 Short-beaked common dolphin (Delphinus delphis) 17 Striped dolphin (Stenella coeruleoalba) 3 Bottlenose dolphin (Tursiops truncatus) 1 White beaked dolphin (Lagenorhynchus albirostris) 1 Atlantic white-sided dolphin (Lagenorhynchus acutus) 1 Leatherback turtle (Dermochelys coriacea) 1 Loggerhead turtle (Caretta caretta) 1 Total 68

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Table D: Post-mortem Investigations conducted in Wales during 2005

Species Number

Harbour porpoise (Phocoena phocoena) 27 Short-beaked common dolphin (Delphinus delphis) 2 Striped dolphin (Stenella coeruleoalba) 1 Bottlenose dolphin (Tursiops truncatus) 1 Long-finned pilot whale (Globicephala melas) 1 Total 32

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Results of UK cetacean and marine turtle post-mortem examinations conducted in 2005

Causes of death Table E summarises the causes of death of 173 cetaceans and three marine turtles examined at post-mortem in the UK in 2005. It was not possible to establish the cause of death of eight UK-stranded harbour porpoises, one bottlenose dolphin, two leatherback turtles and one loggerhead turtle. Causes of cetacean mortality Infectious disease mortality During 2005, 32 harbour porpoises, five short-beaked common dolphins, one bottlenose dolphin, one Atlantic white-sided dolphin and one striped dolphin died owing to infectious diseases (Table E). In the harbour porpoises, these consisted of parasitic infections of the lungs resulting in severe airway obstruction, acute pulmonary haemorrhage, parasitic pneumonia or secondary bacterial or fungal infections (n=21), generalised bacterial infections (n= 9) and parasitic gastritis (n=2). The short-beaked common dolphins died as a result of meningo-encephalitis (n=3), parasitic gastritis (n=1) and a generalised bacterial infection (n=1). The bottlenose dolphin died as a result of a heavy generalised parasitic infection and old age, the Atlantic white-sided dolphin with a generalised bacterial infection, and the striped dolphin with meningo-encephalitis. The spatial distribution of these cases is shown in Figure 1. There were no cases of distemper due to morbillivirus infection in any UK-stranded cetaceans examined at post mortem in 2005. Entanglement in fishing gear (Bycatch) Following post-mortem examination, 24 stranded harbour porpoise carcasses were diagnosed to have died due to bycatch in 2005. An additional two harbour porpoise carcasses were retrieved for post-mortem examination directly from fishing vessels. 14 UK-stranded short-beaked common dolphins were diagnosed as bycatches, all of which were found in or around the south-west of England (Cornwall, Devon and Dorset). Five of these short-beaked common dolphins were retrieved floating at sea by a Greenpeace vessel off the Devon coastline near Plymouth. A single striped dolphin stranded in Cornwall, England was also diagnosed as bycatch in 2005. The spatial distribution of these UK-stranded cetacean bycatches (excluding the harbour porpoises retrieved directly from fishing vessels and the short-beaked common dolphins retrieved by the Greenpeace vessel) examined at post-mortem in 2005 are shown in Figure 2. Trends in cetacean strandings diagnosed as bycatches since 1990 in south-west England (Cornwall, Devon and Dorset) and other UK regions are discussed in more detail in the final report to Defra (Contract no. CRO 238).

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Figure 2 Spatial distribution of 24 stranded harbour porpoises (excluding porpoises retrieved directly from fishing vessels) (rreedd), 14 stranded (or floating at sea) short-beaked common dolphins (bblluuee), and one striped dolphin (yyeellllooww) diagnosed as bycatch in 2005.

Figure 1 Spatial distribution of 32 stranded harbour porpoises (rreedd), five stranded short-beaked common dolphins (bblluuee), one bottlenose dolphin (ggrreeeenn), one Atlantic white sided dolphin (bbllaacckk) and one striped dolphin (yyeellllooww) that died from infectious diseases in 2005.

Physical trauma (including fatal attack from bottlenose dolphins) 25 UK-stranded harbour porpoises were found on post-mortem examination to have died from physical trauma (excluding bycatch) during 2005. Of these, 15 had lesions consistent with fatal attack from bottlenose dolphins comprising seven from west Wales, five from Scotland (generally between the Moray Firth and Firth of Forth areas), one from north-west England and two from south-west England (Devon/Cornwall) (Figure 3). As in previous years, fatal attack from bottlenose dolphins (along with bycatch) was one of the most common causes of death diagnosed in UK-stranded harbour porpoises in 2005. The number of cases diagnosed in west Wales has increased almost annually since 1999. A more detailed analysis of trends in harbour porpoises killed by bottlenose dolphins since 1990 is included in the final report to Defra (Contract no. CRO 238).. Starvation Starvation was diagnosed as the cause of death in animals that were severely emaciated, in the absence of any other underlying disease processes that could explain the poor nutritional status. The deaths of 23 harbour porpoises (including four neonates), two short-beaked common dolphins and single cases of a striped dolphin, a Risso’s dolphin, an Atlantic white-sided dolphin and a white-beaked dolphin were attributed to starvation. The spatial distribution of these cases is shown in Figure 4.

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Figure 3 Spatial distribution of 15 stranded harbour porpoises (rreedd), that died as a result of fatal interactions with bottlenose dolphins in 2005.

Figure 4 Spatial distribution of 23 stranded harbour porpoises (rreedd), two short-beaked common dolphins (bblluuee), one striped dolphin (yyeellllooww), one Risso’s dolphin (oorraannggee), one Atlantic white-sided dolphin (bbllaacckk) and one white beaked dolphin ( ) that died from starvation in 2005.

Live stranding Live stranding was diagnosed as the cause of death in animals that were known or suspected (from post-mortem examination) to have stranded alive while in apparent good health and nutritional status. The cause of death of diseased or emaciated animals that stranded alive was attributed to the disease process rather than the live stranding event. Live stranding was diagnosed as the cause of death in 11 harbour porpoises, four white beaked dolphins, three Atlantic white-sided dolphins, three short-beaked common dolphins and single cases of a striped dolphin, a Risso’s dolphin and a pilot whale. The spatial distribution of these cases is shown in Figure 5.

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Figure 5 Spatial distribution of 11 stranded harbour porpoises (rreedd), four white beaked dolphins ( ), three Atlantic white-sided dolphins (bbllaacckk), three short-beaked common dolphins (bblluuee), one striped dolphin (yyeellllooww), one Risso’s dolphin (oorraannggee) and one pilot whale (ttuurrqquuooiissee) diagnosed as live strandings in 2005.

Other causes of death The other remaining causes of death of the stranded cetaceans and marine turtles examined in 2005 are listed in Table E.

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Table E: Causes of death of cetaceans and marine turtles examined at post

mortem in the UK in 2005

Species Cause of death category No. Harbour porpoise Bycatch* 26 Starvation (including four neonates) 23 Pneumonia (parasitic/bacterial/mycotic) 21 Physical trauma (bottlenose dolphin attack) 15 Live Stranding 11 Physical trauma (unidentified cause) 10 Generalised bacterial infection 9 Gastropathy and/or Enteropathy 2 Others 1 Not established 8 Short-beaked common dolphin Bycatch 14 Live Stranding 3 (Meningo) encephalitis 3 Starvation 2 Gastropathy and/or Enteropathy 1 Generalised bacterial infection 1 Others 1 Striped dolphin Bycatch 1 Live Stranding 1 (Meningo) encephalitis 1 Starvation 1 Others 1 White-beaked dolphin Live Stranding 4 Starvation 1 White-sided dolphin Live stranding 3 Starvation 1 Generalised bacterial infection 1 Bottlenose dolphin Pneumonia (Parasitic) 1 Not Established 1 Risso’s dolphin Live stranding 1 Starvation 1 Long-finned pilot whale Live Stranding 1 Others 1 Minke whale Entanglement 1 Leatherback turtle Not Established 2 Loggerhead turtle Not Established 1

* Of the 26 harbour porpoise bycatches reported here, two were carcasses retrieved directly from fishing vessels.

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Investigations of relationships between environmental contaminants and health status Toxicology data from UK-stranded harbour porpoises Tissue samples for toxicological analyses continued to be collected and archived from stranded marine mammals examined during 2005. Samples taken from 65 stranded cetaceans (predominantly harbour porpoises) were sent to the CEFAS Burnham Laboratory, Essex (CEFAS) for toxicological analyses during 2005. Investigations of potential relationships between exposure to persistent environmental pollutants and health status in UK harbour porpoises continued in 2005 in collaboration with the Sea Mammal Research Unit (University of St Andrews) and the CEFAS Burnham Laboratory, Essex. A case-control study in 257 harbour porpoises demonstrating statistically significant associations between elevated blubber polychlorinated biphenyls (PCBs) levels and infectious disease mortality (compared to controls that died of acute physical trauma) was published in 2005 (Jepson et al. 2005a). This association was not confounded by a range of factors including age, sex, stranding location and two quantitative indices of nutritional status, and was considered consistent with PCB-induced immunosuppression leading to increased risk of mortality due to infectious disease (Jepson et al. 2005a). This type of analysis enables dose-response relationships between PCB exposure and lethal effect to be generated using empirical pathological and toxicological data, and may form the basis of future risk assessments predicting the population level impacts of PCBs in populations of known size and PCB exposure. A range of analyses of toxicological and pathological data generated in stranded harbour porpoises have been included in the final report to Defra (Contract no. CRO 238). These analyses include trends in contaminant exposure (organochlorine pesticides, chlorinated biphenyl congeners, heavy metals, butyltins and polybrominated flame retardants) in harbour porpoises stranded in the UK between 1989 and 2001 and investigations of potential relationships between exposure to these contaminants and health status in stranded harbour porpoises (see also Jepson 2003). Gas embolism Detailed pathological findings in 10 cetaceans that stranded in the UK between 1992 and 2004 with acute and chronic gas embolic lesions were published in 2005 (Jepson et al. 2005b). These animals consisted of four common dolphins, four Risso’s dolphins, a Blainville’s beaked whale (Mesoplodon densirostris) and a harbour porpoise. Brief details of eight of these UK cases have been published previously and in conjunction with cases of gas embolism in a beaked whale mass-stranding in the Canary Islands in 2002 (Jepson et al. 2003; Fernandez et al. 2004). There were no new cases of gas embolism recorded in any UK cetaceans in 2005. Additional collaborative research activity A number of collaborative research activities were supported by access to data and/or tissue samples collated by the Defra-funded UK Cetacean and Turtle Strandings Programme.

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• A NERC-funded PhD studentship investigating the population structure of

harbour porpoises in UK waters using genetic (microsatellite) markers was submitted as an MPhil in 2005. The research was jointly supervised by the Institute of Zoology and Cambridge University.

• Institute of Zoology (Zoological Society of London). A collaborative research

programme to develop population-based models for the dynamics of parasites and their mammalian hosts, utilising data from UK stranded cetaceans (specifically harbour porpoises), was continued in 2005 in collaboration with Dr. Andrew Fenton and Dr. James Bull.

• Professor Antonio Fernandez, Facultad de Veterinaria Universidad de Las Palmas

de Gran Canaria, Spain. Pathological investigations into gas and fat embolism in cetaceans.

• Dr. Simon Northridge, Sea Mammal Research Unit, Gatty Marine Laboratory,

University of St. Andrews, St Andrews, Fife. Teeth and stomach contents from cetaceans stranded in England and Wales are routinely sent for teeth ageing and stomach content analysis respectively. These biological data from stranded cetaceans form an integral part of additional Defra-funded research on cetacean bycatch co-ordinated by the Sea Mammal Research Unit.

• Dr. Ailsa Hall, Sea Mammal Research Unit, Gatty Marine Laboratory, University of

St. Andrews, St Andrews, Fife. Risk-assessment analyses of impacts of polychlorinated biphenyls (PCBs) on populations of harbour porpoises.

• Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik,

Midlothian, EH26 0PZ, Scotland. Expert neurohistopathological studies on cetacean tissues from Scottish cetaceans.

• Dr. Graham Pierce, University of Aberdeen, Department of Zoology, Lighthouse

Field Station, George Street, Cromarty, Ross-shire IV11 8YJ. Collaboration on life history, dietary and toxicological studies of harbour porpoises and other cetaceans (including internationally collaborative EU-funded BIOCET project completed in 2005).

• Dr. Paul Thompson, University of Aberdeen, Department of Zoology, Lighthouse

Field Station, George Street, Cromarty, Ross-shire IV11 8YJ. Collaboration on biological studies of harbour porpoises and bottlenose dolphins.

• Dr. Krishna Das, Laboratory for Oceanology, MARE Center, B6c, Liège

University, B-4000 Liège, Belgium/Dr. Ursula Siebert, Forschungs- und Technologiezentrum Westkueste Hafentoern D-25761 Buesum Germany. A collaboration investigating the potential thyrotoxic histopathological effects of persistent organic pollutants (such as PCBs) on thyroid microanatomy continued with these research institutes in 2005.

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• Dr. Ursula Siebert, Forschungs- und Technologiezentrum Westkueste Hafentoern D-25761 Buesum Germany. On 1st October 2004, the Institute of Zoology began a small (Defra-funded) 2-year project to examine the feasibility of using formalin-fixed auditory tissue (ears) collected from UK stranded cetaceans to investigate potential auditory impacts of anthropogenic noise exposure. The research is in collaboration with the Forschungs und Technologiezentrum Westkueste, Buesum, Germany.

• Dr Andrew Kitchener, Royal Museum of Scotland, Edinburgh, Scotland. Recording

all marine mammal stranding events in Scotland. Marine mammal skulls and scapulae are sent to Dr. Kitchener for marine mammal morphometric studies.

• Dr Alistair MacMillan, Brucella Section, Veterinary Laboratories Agency, New Haw,

Addlestone, Surrey, KT15 3NB. Serological studies to assess exposure to Brucella spp. and typing of Brucella isolates.

• Dr Jacques Godfroid, Centre d'etude et de la Recherches Veterinaires et

Agronomiques, B-1180 Brussels, Belgium. Molecular typing of Brucella isolates. • Professor David Collins, University of Reading, Reading RG6 6AP. Sequencing of

novel bacterial isolates. Scientific Meetings attended In 2005, the Technical Co-ordinator of scientific research (Dr Paul Jepson) was an invited speaker/participant at the following meetings relating to the impacts of anthropogenic noise on marine mammals:- • Inter-Agency Committee on Marine Science and Technology Working Group on

Underwater Noise and Marine Life (February 2005; London, UK) • Beaked whale/active sonar workshop at the annual scientific conference of the

European Cetacean Society (April 2005; La Rochelle, France) • Intergovernmental conference on Noise and Marine Mammals organised by the

US Office of Naval Research and the UK Defence Science and Technology Laboratory (May 2005; Lereci, Italy)

• Scientific meeting to develop an International Strategy for Scientific Research on the Effects of Noise on Marine Mammals (October 2005; Oxford, UK)

Additional Report writing Dr Paul Jepson (Institute of Zoology) co-authored a 2005 International Convention of the Exploration of the Seas (ICES) ad-hoc working group report on the “Impact of Sonar on Cetaceans”. Advice deriving from the report was commissioned by the European Commission. Student theses The following student theses were completed in 2005 using samples and/or data collated by the UK Marine Mammal Strandings Research Programme.

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MPhil theses

• Thatcher, O.R. (2005) Genetic population structuring and relationships between heterozygosity and susceptibility to parasitic disease in the harbour porpoise Phocoena phocoena population of Great Britain. MPhil thesis. Magdalene College, University of Cambridge. Pp.1-143. July 2005.

MSc theses

• Provan, H. (2005) The condition scoring of stranded cetaceans using direct and indirect techniques. Submitted in part fulfilment of the requirements for the degree of Master of Science in Wild Animal Health, University of London, 2005

• Zachariah, A. (2005) Evidence of leptospirosis in phocid seals of coastal United Kingdom. Submitted in part fulfilment of the requirements for the degree of Master of Science in Wild Animal Health, University of London, 2005

2005 Publications Jepson, P.D., Bennett, P.M., Deaville, R., Allchin, C.R., Baker, J.R. and Law, R.J. (2005a) Relationships between polychlorinated biphenyls and health status in harbour porpoises (Phocoena phocoena) stranded in the United Kingdom. Environmental Toxicology and Chemistry 24(1): 238-248. Jepson, P.D., Deaville, R., Patterson, I.A.P., Pocknell, A.M., Ross, H.M., Baker, J.R., Howie, F.E., Reid, R.J., Colloff, A. and Cunningham, A.A. (2005b) Acute and chronic gas bubble lesions in cetaceans stranded in the United Kingdom. Veterinary Pathology 42: 291-305 Law, R.J., Allchin, C.R. and Mead, L.K. (2005). Brominated diphenyl ethers in twelve species of marine mammals stranded in the UK. Marine Pollution Bulletin, 50, 356-359. Lawson, P. A., Foster, G., Falsen, E. and Collins, M. D. (2005) Streptococcus marimammalium sp. nov., isolated from seals. International Journal of Systematic and Applied Microbiology 55:271-274. MacLeod, C.D., Bannon, S.M., Pierce, G.J., Schweder, C., Learmonth, J.A., Herman, J.S. and Reid, R.J. (2005) Climate Change and the Cetacean Community of North-West Scotland. Biological Conservation 124: 477-483 Conference abstracts Deaville, R., Baker, J.R., Penrose, R.S., Jepson, P.D. (2005) Increasing incidence of stranded harbour porpoises (Phocoena phocoena) killed by bottlenose dolphins (Tursiops truncatus) in England and Wales - a bio-indicator of habitat degradation? Proceedings of the 19th annual conference of the European Cetacean Society, La Rochelle, France, 2-7 April 2005.

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Jepson, P.D., Houser, D.S., Crum, L.A., Tyack, P.L. & Fernández, A. Beaked whales, sonar and the “bubble hypothesis”. (2005) Proceedings of the nineteenth Annual Conference of the European Cetacean Society, La Rochelle, France, 4-7 April 2005 Jepson, P.D., Houser, D.S., Crum, L.A., Tyack, P.L. & Fernández, A. Beaked whales, sonar and the “bubble hypothesis”. (2005) Proceedings of the sixteenth Biennial Conference of the Society for Marine Mammalogy, San Diego, USA, 12-16 December 2005 References cited Evans, W.E. (1994) The Handbook of Marine Mammals Vol.5 – the First Book of Dolphins. S. Ridgway and R. Harrison (eds). Academic Press, London. Evans, P.G.H. (1995) Guide to the Identification of Whales, Dolphins and Porpoises in European Seas. Sea Watch Foundation Publication, Oxford, 1995. Fernandez, A., Arbelo, M., Deaville, R., Patterson, I.A.P., Castro, P., Baker, J.R., Degollada, E., Ross, H.M., Herráez, P., Pocknell, A.M., Rodriguez, E., Howie, F.E., Espinosa, A., Reid, R.J., Jaber, J.R., Martin, V., Cunningham, A.A., and Jepson, P.D. (2004) Whales, sonar and decompression sickness (reply). Nature, doi:10.1038/nature02528 Jefferson, T.A., Leatherwood, S., Webber, M.A. (1993) FAO Species Identification Guide. Marine Mammals of the World. United Nations Environment Programme, Food and Agriculture Organization of the United Nations, Rome, 1993. Jepson, P.D. (2003) Pathology and toxicology of stranded harbour porpoises (Phocoena phocoena) in UK waters. PhD thesis. Royal Veterinary College (University of London). Pp.1-221. July 2003. Jepson, P.D., Arbelo, M., Deaville, R., Patterson, I.A.R., Castro, P., Baker, J.R., Degollada, E., Ross, H.M., Herráez, P., Pocknell, A.M., Rodriguez, E., Howie, F.E., Espinosa, A., Reid, R.J., Jaber, J.R., Martin, V., Cunningham, A.A., and Fernandez, A. (2003) Gas-bubble lesions in stranded cetaceans. Nature, 425, 575-576 Jepson, P.D., Bennett, P.M., Deaville, R., Allchin, C.R., Baker J.R. & Law, R.J. (2005a) Relationships between PCBs and health status in UK-stranded harbour porpoises (Phocoena phocoena). Environmental Toxicology and Chemistry 24, 238–248 Jepson, P.D., Deaville, R., Patterson, I.A.R., Pocknell, Ross, H.M., Baker, J.R., Howie, F.E., Reid, R.J., Colloff, A. and Cunningham, A.A. (2005b) Acute and chronic gas bubble lesions in cetaceans stranded in the United Kingdom. Veterinary Pathology 42: 291-305

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Muir, A.I., Chimonides, P.D.J. & Spurrier, C.J.H. (1999) Trends in Cetacean Strandings on the British Coastline, 1998. The Natural History Museum, London. Penrose, R.S. (2006) Marine Mammal and Marine Turtle Strandings (Welsh Coast) Annual Report 2005. Marine Environmental Monitoring, February 2006. Perrin, W.F. & Reilly, S.B. (1984) Reproductive parameters of dolphins and small whales of the family Delphinidae. In: Reproduction in Whales, Dolphins and Porpoises (Eds W.F. Perrin, R.L. Brownwell and D.P. DeMaster) pp.97-133. Rep. Int. Whal. Comm, Spec. Issue No. 6, Cambridge. Reid, J. B., Evans, P. G. H. and Northridge, S. P. (2003) Atlas of Cetacean Distribution in North-West European Waters. Joint Nature Conservation Committee. Whitehead, H. (2002) Sperm whale Physeter macrocephalus. In: Encyclopedia of Marine Mammals (Eds W.F. Perrin, B. Wursig and J.G.M Thewissen) p. 1165. Academic Press.

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Appendix 1. UK cetacean distribution maps (all categories reported) by species, 2005

Map 1. All UK records of cetacean strandings, 2005

37

Map 2. Minke whale, fin whale and unidentified baleen whale strandings, 2005

38

39

Map 3. Short-beaked common dolphin strandings etc, 2005.

40

Map 4. Long-finned pilot whale, Risso’s dolphin and killer whale strandings etc, 2005.

41

Map 5. White sided, white beaked, bottlenose and striped dolphin strandings, 2005.

42

Map 6. Harbour porpoise strandings etc, 2005.

43

Map 7. Sperm whale, Sowerby’s beaked whale, Cuvier’s beaked whale and unidentified beaked whale strandings, 2005.

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Map 8. Unidentified cetacean strandings etc, 2005.

Appendix 2. Stranded cetacean lengths by species, UK, 2005 2.1. Minke whale

SW. number

Date of stranding

County/Region Sex Total length (metres)

2005/166a 26-Jun-05 Strathclyde F 7 2005/198b 26-Jul-05 Highland - 4.5 2005/198d 26-Jul-05 Highland - - 2005/204d 06-Aug-05 Highland - - 2005/204f 08-Aug-05 Grampian - 8 2005/204g 08-Aug-05 Highland - 8 2005/226c 01-Sep-05 Strathclyde - 8 2005/247 06-Oct-05 Strathclyde - 8.7 2005/248a 08-Oct-05 Orkney Islands F 7.8 2005/253c 15-Oct-05 Grampian - 10 2005/256 18-Oct-05 Lincolnshire M 5.94 2005/256a 19-Oct-05 Grampian - 7 2005/287b 08-Dec-05 Highland - 5 2005/287d 11-Dec-05 Orkney Islands F 5.53

2.2. Fin whale SW. number

Date of stranding

County/Region Sex Total length (metres)

2005/278 19-Nov-05 Hampshire M 13.41

2.3. Long-finned pilot whale SW. number

Date of stranding

County/Region Sex Total length (metres)

2005/12g 18-Jan-05 Dorset - 3.6 2005/17b 20-Jan-05 Strathclyde - 5 2005/28b 07-Feb-05 Strathclyde M 2.64 2005/30a 10-Feb-05 Western Isles - 7 2005/31c 13-Feb-05 Western Isles - 2.1 2005/68a 22-Mar-05 Devon ?M 4.5 2005/90 05-Apr-05 Devon - 3.9 2005/156b 13-Jun-05 Orkney Islands - 6.1 2005/181 06-Jul-05 Pembrokeshire F 4.62 2005/187b 14-Jul-05 Western Isles M 5.8 2005/188b 15-Jul-05 Highland - 1.8 2005/197a 23-Jul-05 Strathclyde F 4 2005/201a 28-Jul-05 Highland M 6 2005/202d 31-Jul-05 Highland - 4 2005/225a 29-Aug-05 Highland - 1.8 2005/239a 26-Sep-05 Orkney Islands - - 2005/243c 29-Sep-05 Orkney Islands - 3.1 2005/257 20-Oct-05 Devon - 2.74 2005/270 07-Nov-05 Dorset F 5.43

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2.4. Risso’s dolphin

SW. number

Date of stranding

County/Region Sex Total length (metres)

2005/42b 1 24-Feb-05 Highland - 3 2005/59f 1 13-Mar-05 Highland - 2.7 2005/61e 1 15-Mar-05 Orkney Islands - 2.36 2005/142d 1 04-Jun-05 Orkney Islands - 3.36 2005/156a 1 13-Jun-05 Shetland Isles - 0 2005/159e 1 15-Jun-05 Grampian - 3.3 2005/159i 1 15-Jun-05 Orkney Islands - 3.5 2005/194a 1 21-Jul-05 Western Isles F 2.99 2005/197c 1 24-Jul-05 Highland - 3.2 2005/204h 1 09-Aug-05 Orkney Islands - 2.07 2005/226e 1 02-Sep-05 Grampian F 3.08 2005/243d 1 29-Sep-05 Shetland Islands M 1.41 2005/290a 1 19-Dec-05 Shetland Islands - 3

2.5. White-sided dolphin

SW. number

Date of stranding

County/Region Sex Total length (metres)

2005/59e 12-Mar-05 Shetland Isles M 2.4 2005/159f 18-Jun-05 Western Isles M 2.41 2005/163b.1 23-Jun-05 Shetland Isles - 0 2005/163b.2 23-Jun-05 Shetland Isles - 0 2005/204e 07-Aug-05 Western Isles M 2.58 2005/212 15-Aug-05 Norfolk F 2.25 2005/212c 15-Aug-05 Fife M 2.3 2005/253a 13-Oct-05 Grampian M 2.5 2005/275a 15-Nov-05 Strathclyde - 2.2

2.6. White-beaked dolphin

SW. number

Date of stranding

County/Region Sex Total length (metres)

2005/60c 14-Mar-05 Highland - 1.57 2005/76g 27-Mar-05 Orkney Islands - 2 2005/85 03-Apr-05 North Yorkshire F 2.03 2005/133a 28-May-05 Fife F 2.49 2005/197b 23-Jul-05 Highland M 1.25 2005/202c 31-Jul-05 Highland M 1.35 2005/212d 16-Aug-05 Highland - 1.2 2005/283a 02-Dec-05 Orkney Islands M 2.39

2.7. Striped dolphin

SW. number

Date of stranding

County/Region Sex Total length (metres)

2005/1f 03-Jan-05 Highland - 1.7 2005/19b 23-Jan-05 Highland M 1.65 2005/38 23-Feb-05 Carmarthenshire F 1.53 2005/137a 02-Jun-05 Hampshire M 1.86 2005/138a 03-Jun-05 Cornwall M 2.03 2005/247a 07-Oct-05 Cornwall (N) F 1.93 2005/262b 29-Oct-05 Cornwall F 1.6

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2.8. Bottlenose dolphin SW. number

Date of stranding

County/Region Sex Total length (metres)

2005/151b 09-Jun-05 Fife F 3.2 2005/193 20-Jul-05 Ceredigion F 3.1 2005/209 14-Aug-05 Denbighshire F 3.18 2005/254a 16-Oct-05 Highland - 3.5 2005/269 07-Nov-05 Dorset - 3 2005/271 08-Nov-05 Cornwall M 3.2 2005/292b 27-Dec-05 Grampian - 2

2.9. Sperm whale

SW. number

Date of stranding

County/Region Sex Total length (metres)

2005/109c 20-Apr-05 Highland - 11 2005/127f 24-May-05 Orkney Islands M 11.84 2005/166b 27-Jun-05 Western Isles M 13 2005/188c 18-Jul-05 Western Isles - 13 2005/213e 18-Aug-05 Highland - 15

2.10. Sowerby’s beaked whale

SW. number

Date of stranding

County/Region Sex Total length (metres)

2005/18f 22-Jan-05 Grampian M 4.7 2.11. Cuvier’s beaked whale

SW. number

Date of stranding

County/Region Sex Total length (metres)

2005/1e 02-Jan-05 Strathclyde - 5 2005/4b 10-Jan-05 Western Isles F 3.13 2005/285b 05-Dec-05 Orkney Islands - 4.75

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Consultancy ReportTRENDS IN CETACEAN STRANDINGS AROUNDTHE UK COASTLINE, CETACEAN AND MARINE TURTLEPOST-MORTEM INVESTIGATIONS 2005(CONTRACT CRO 346)Introduction 7Results 8Distribution of cetacean species 12Balaenoptera acutorostrata – minke whale 12Lagenorhynchus acutus – white-sided dolphin 16Causes of death 26Toxicology data from UK-stranded harbour porpoises 31Gas embolism 31Additional collaborative research activity 31R. Penrose: Marine Environmental Monitoring (MEM)ABSTRACTThe first evidence of cetacean gas and fat embolism and assoPart ATRENDS IN CETACEAN STRANDINGS AROUND THE COASTLINE OF THE UNIntroductionTable 2: Reported cetacean strandings etc. in the UK for 20SCOTLANDSTATES OF JERSEYTOTALMinke whaleFin whaleUnidentified rorqualShort-beaked common dolphinHarbour porpoiseSowerby’s beaked whaleCuvier’s beaked whaleUnidentified beaked whale

Table 3. Numbers of all cetacean species stranded around th

2001Minke whaleSei whaleFin whaleShort-beaked common dolphinHarbour porpoisePygmy sperm whaleSperm whaleNorthern bottlenose whaleSowerby’s beaked whale

Cuvier’s beaked whaleUnidentified beaked whaleIn 2005, the NHM received 12 reports of unidentified toothedPart BUK Cetacean and Marine Turtle Post-mortem Investigations 200Table A: UK Cetacean and Marine Turtle Post-mortem InvestigaNumberNumberHarbour porpoise (Phocoena phocoena)56Short-beaked common dolphin (Delphinus delphis)6Atlantic white-sided dolphin (Lagenorhynchus acutus)4White beaked dolphin (Lagenorhynchus albirostris)4Striped dolphin (Stenella coeruleoalba)11Total76Table C: Post-mortem Investigations conducted in England dur

SpeciesNumberBottlenose dolphin (Tursiops truncatus)1Leatherback turtle (Dermochelys coriacea)1Loggerhead turtle (Caretta caretta)1Table D: Post-mortem Investigations conducted in Wales durin

SpeciesNumberBottlenose dolphin (Tursiops truncatus)1

Causes of deathCauses of cetacean mortalityInfectious disease mortalityStarvationLive strandingToxicology data from UK-stranded harbour porpoisesReferences cited

Jepson, P.D., Bennett, P.M., Deaville, R., Allchin, C.R., BaMuir, A.I., Chimonides, P.D.J. & Spurrier, C.J.H. (1999) Tr