F.R.V. Scotia Mackerel Egg Survey 2010

Transcription

1 F.R.V. Scotia Mackerel Egg Survey 2010 Cetacean Distribution & Relative Abundance Survey 4 th May 11 th May 2010 Sowerby s beaked whales breaching, Rockall Trough ( Dave Wall) Surveyor: Dave Wall Ship Surveys Programme Irish Whale and Dolphin Group Marine Biodiversity Research Group Galway-Mayo Institute of Technology Introduction

2 The waters of Ireland s Exclusive Economic Zone (EEZ) are thought to represent one of the most important cetacean (whales, dolphins and porpoise) habitats in Europe. To date 24 species of cetacean have been recorded (Appendix I), with seven of these having been confirmed as calving within the Irish EEZ, while a number of other species are possibly calving (e.g. minke whale and northern bottlenose whale) (Berrow 2001). In recognition of their importance for cetaceans, the Irish government declared all Irish waters (within the EEZ) to be a whale and dolphin sanctuary in 1991 (Rogan and Berrow 1995). Despite this recognition, information on the distribution and relative abundance of cetaceans within the Irish EEZ, especially in offshore waters, is very limited (Wall et al. 2006). The Irish Whale and Dolphin Group (IWDG) have been collecting data on the distribution and relative abundance of cetaceans in Irish waters (including Northern Ireland) since The IWDG casual and constant effort sightings schemes record data mainly from land-based sightings and surveys (Berrow et al. 2001). The IWDG has conducted cetacean surveys on board commercial ferries since 2001, on board research vessels since 2003 and on board naval service vessels since In 2008, the IWDG in collaboration with the Galway-Mayo Institute of Technology commenced PReCAST, a three-year project ( ) which aims to provide robust scientific data to support conservation policy and provide guidance to state agencies in implementing national and international obligations. PReCAST is committed to gaining a more complete understanding of the seasonal distribution, relative abundance and habitat use of cetaceans within the Irish EEZ. As part of this project a cetacean distribution and relative abundance survey was conducted on board the Scottish Fisheries Research Services vessel Scotia during the Mackerel Egg Survey from 4 th - 11 th May 2010.

3 Methods The survey was conducted on board the Scottish Fisheries Research Services vessel Scotia during the Mackerel Egg Survey between 4 th and 11 th May The survey area covered waters over the western Irish Shelf, Rockall Trough, northern Scottish shelf and North Sea. The survey areas were opportunistic and based on survey transects chosen for the ICES Mackerel Egg Survey A single marine mammal observer was present on board during the survey and conducted watches from the ships bridge nest located 10m above sea level. Observer effort focused on a 90-degree arc ahead of the ship; however sightings located up to 90 degrees to port and starboard were also included. The observer scanned the area by eye and using 10 X 40 binoculars. Bearings to sightings were measured using an angle board and distances were estimated with the aid of distance measuring stick. Environmental data were recorded every 15 minutes using Logger 2000 software (IFAW 2000). Sightings were also recorded using Logger Automated position data were obtained through a laptop computer linked to GPS receiver. As this was a survey onboard a vessel of opportunity, the survey was conducted in passing mode and cetaceans sighted were not approached. Sightings were identified to species level where possible, with species identifications being graded as definite, probable or possible. Where species identification could not be confirmed, sightings were downgraded (e.g. unidentified dolphin / unidentified whale / unidentified beaked whale etc.) according to criteria established for the IWDG s cetacean sightings database (IWDG 2010).

4 Results Environmental Conditions Environmental data was collected at 218 stations. Sea state was 3 at 3.2% of environmental stations, 4 at 23.4% of stations and 5 at 68.3% of stations. Visibility was >5km at 87.6% of stations, 1 5km at 23.9% of stations and <1km at 0.5% of stations. Swell of 2m+ was recorded at 17% of stations. Fog was recorded at 9.2% of stations, rainfall was recorded at 0.9% of stations and snow was recorded at 1 station (fig. 1). No survey effort was lost due to bad weather but survey effort was continued in poor weather conditions (sea state 6+) in order to survey for large baleen whales and breaching beaked whales. 8 Sea State (Beaufort) Visibility (0-4) Swell (0-3) /05/2010 AM 05/05/2010 PM 06/05/2010 AM 06/05/2010 PM 07/05/2010 AM 07/05/2010 PM 08/05/2010 AM 08/05/2010 PM 09/05/2010 AM 09/05/2010 PM 10/05/2010 AM 10/05/2010 PM Date/Time Figure 1. Sea state, swell conditions and visibility recorded twice daily during days on survey. Cetacean Visual Survey Results hours of survey time were logged with 3.1% (1.43 hrs) of this at Beaufort sea state three or less; 23% (10.72 hrs) at Beaufort sea state four or less and 69.2% (32.23 hrs) at Beaufort sea state five or less. Five sightings of three cetacean species, totalling 46 individuals were recorded (fig. 2).

5 Figure 2. Distribution and group size of cetacean species recorded during the survey. Identified cetacean species were common dolphin (Delphinus delphis), pilot whale (Globicephala melas) and Sowerby s beaked whale (Mesplodon bidens). Table 1. Sightings, counts and group size ranges for cetaceans sighted during the survey. Species No. Sightings No. Individuals Range of Group Size Juveniles/ Calves Common dolphin Pilot whale Sowerby s beaked whale Bird Activity Daily species lists were made of all seabird species seen around the survey vessel. 15 seabird species were recorded during the survey: puffin (Fratercula arctica), guillemot (Uria aalge); gannet (Morus bassanus); razorbill (Alca torda); fulmar (Fulmarus glacialis); kittiwake (Rissa tridactyla); black-headed gull (Larus ridibundus); lesser black backed gull (Larus fuscus); great black-backed gull (Larus marinus); herring gull (Larus argentatus); great skua (Stercorarius skua); parasitic skua (Stercorarius parasiticus); manx shearwater (Puffinus puffinus); great northern diver (Gavia immer); storm petrel (Hydrobates pelagicus).

6 References Berrow, S.D., Whooley, P. and Ferriss, S. (2001) Irish Whale and Dolphin Group cetacean sighting schemes: development of a system to record sightings of cetaceans (whales, dolphins and porpoises) in Irish waters. Final report to the Heritage Council (Ireland), Kilkenny. IFAW (2000) Logger 2000 software. Inter-national Fund for Animal Welfare, London. IWDG (2009) IWDG Cetacean Sightings Database (Rep. Ireland & Northern Ireland). Ó Cadhla, O., Mackey, M., Aguilar de Soto, N., Rogan, E. & Connolly, N. (2004). Cetaceans and Seabirds of Ireland s Atlantic Margin. Volume II Cetacean distribution & abundance. Report on research carried out under the Irish Infrastructure Programme (PIP): Rockall Studies Group (RSG) projects 98/6 and 00/13, Porcupine Studies Group project P00/15 and Offshore Support Group (OSG) project 99/38. 82pp. Rogan, E. and Berrow, S.D. (1995) The management of Irish waters as a whale and dolphin sanctuary. In A.S. Blix, L. Walløe and Ø. Ulltang (eds), Whales, seals, fish and man, Amsterdam. Elsevier Science. Wall D., O Brien J., Meade J. & Allen B.M. (2006) Summer distribution and relative abundance of cetaceans off the west coast of Ireland. Biology and Environment: Proceedings of the Royal Irish Academy, 106B (2),

7 Previous Survey Reports Kavanagh L. (2010) Cetacean Distribution and Relative Abundance Survey during German Mackerel Egg Survey Report to the Bundesforschungsinstitut für ländliche Räume, Wald und Fischerei, Hamburg, Germany. Wall D. (2010) Cetacean Distribution and Relative Abundance Survey during FSS Mackerel Egg Survey Report to the Marine Institute, Oranmore, Ryan C. (2009) Cetacean Distribution and Relative Abundance Survey during NUIG Bright Sparks Survey Report to the National University of Ireland, Wall D. and O Brien J. (2009) Cetacean Distribution and Relative Abundance Survey during the NPWS Geogenic Reef Habitat Mapping Survey Cruise Report to the National Parks and Wildlife Service, 7 Ely Place, Dublin 2. Wall D. et al. (2010) Cetaceans on the Frontier Survey Cruise report to the Marine Institute, Oranmore, O Brien J. (2010) Cetacean Distribution and Relative Abundance Survey during the Marine Institute Oceanographic Survey Report to the Marine Relative Abundance Survey during the AFBI Autumn Herring Acoustic Survey Cruise Report to the Agriculture, Food and Biosciences Institute, Belfast. Wall D. et al. (2009) Cetaceans on the Frontier Survey Cruise report to the Marine Institute, Oranmore, Wall D. (2010) Cetacean Distribution and Relative Abundance Survey during the LE Roisín & LE Niamh January Patrol Cruise Report to Irish Naval Service, Haulbowline, Cork, Ireland. Abundance Survey during FSS Deepwater Survey Report to the Marine Institute, Oranmore, O Brien J. (2009) Cetacean Distribution and Relative Abundance Survey during FSS Groundfish Survey Report to the Marine Institute, Oranmore, Abundance Survey during FSS Southwest Herring Acoustic Survey Report to the Marine Relative Abundance Survey during the AFBI Biological Oceanography Survey Cruise Report to the Agriculture, Food and Biosciences Institute, Belfast. Relative Abundance Survey during the AFBI Nephrops Survey Cruise Report to the Agriculture, Food and Biosciences Institute, Belfast. Relative Abundance Survey during the AFBI Summer Herring Acoustic Survey Cruise Report to the Agriculture, Food and Biosciences Institute, Belfast. Kavanagh L. (2009) Cetacean Distribution and Relative Abundance Survey during FSS Northwest

8 Herring Acoustic Survey Cruise Report to the Marine Report to the Agriculture, Food and Biosciences Institute, Belfast. Abundance Survey during the NUI Galway, Climate Change Survey Cruise Report to National University of Ireland, Relative Abundance Survey during the Marine Institute Nutrient Survey Report to the Marine Relative Abundance Survey during the AFBI Juvenile Gadoid Survey Cruise Report to the Agriculture, Food and Biosciences Institute, Belfast. Abundance Survey during the LE Niamh January Patrol Report to Irish Naval Service, Haulbowline, Cork, Ireland. Abundance Survey during the NUI Galway, Coralfish Survey Cruise Report to National University of Ireland, Wall D. (2008) Cetacean Distribution and Relative Abundance Survey during the LE Róisín December Patrol Report to Irish Naval Service, Haulbowline, Cork, Ireland. Abundance Survey during the LE Emer April Patrol Cruise Report to Irish Naval Service, Haulbowline, Cork, Ireland. Tuffy P. (2008) Cetacean Distribution and Relative Abundance Survey during IFREMER Groundfish Survey Report to the French Institute for the Exploitation of the Sea. O Brien J. (2009) Cetacean Distribution and Relative Abundance Survey during the Tridens Blue Whiting Survey Report to the Dutch Ministry of Agriculture, Nature and Food Quality (LNV), Den Haag, The Netherlands. Murray C. (2008) Cetacean Distribution and Relative Abundance Survey during CEFAS Groundfish Survey Report to the Centre for Environment, Food and Agriculture Sciences, Suffolk, England. Relative Abundance Survey during the AFBI Groundfish Survey Report to the Agriculture, Food and Biosciences Institute, Belfast. Tuffy P. (2008) Cetacean Distribution and Relative Abundance Survey during AFBI Groundfish Survey Report to the Agriculture, Food and Biosciences Institute, Belfast. Abundance Survey during the Marine Institute Oceanographic Survey Report to the Marine Wall D. (2008) Cetacean Distribution and Relative Abundance Survey during FSS Southwest Herring Acoustic Survey Report to the Marine Tuffy P. (2009) Cetacean Distribution and Relative Abundance Survey during AFBI Gadoid Survey Wall D. (2008) Cetacean Distribution and Relative Abundance Survey during FSS Deep Water Survey

9 2008. Report to the Marine Institute, Oranmore, Murray C. (2008) Cetacean Distribution and Relative Abundance Survey during AFBI Nephrops Assessment Survey Report to the Agri-Food and Biosciences Institute, Northern Ireland. Wall D. (2008) Cetacean Distribution and Relative Abundance Survey during NIOZ Cold Water Coral Fish Survey Report to the Royal Netherlands Institute for Sea Research and the Marine Institute, Oranmore, Wall D. (2008) Cetacean Distribution and Relative Abundance Survey during FSS Blue Whiting Acoustic Survey Report to the Marine Baer J. (2008) Cetacean Distribution and Relative Abundance Survey during CEFAS Irish Sea Plankton Survey Report to the Centre for Environment, Fisheries & Aquaculture Science and the Marine Wall D. (2007) Cetacean Distribution and Relative Abundance Survey during Rockall Trough Oceanographic Survey Report to the Marine Wall D. (2007) Cetacean Distribution and Relative Abundance Survey during FSS Northwest Herring Acoustic Survey Report to the Marine Wall D. (2006) Cetacean Distribution and Relative Abundance Survey during FSS Southwest Herring Acoustic Survey Report to the Marine Wall D. (2006) Cetacean Distribution and Relative Abundance Survey during FSS Deep Water Survey Report to the Marine Institute, Oranmore, Wall D. (2005) Cetacean Distribution and Relative Abundance Survey during FSS Southwest Herring Acoustic Survey Report to the Marine Wall D. (2007) Cetacean Distribution and Relative Abundance Survey during FSS Southwest Herring Acoustic Survey Report to the Marine Wall D. (2005) Cetacean Distribution and Relative Abundance Survey during Irish Seabed Survey: Leg 17. Report to the Marine Institute, Oranmore, Wall D. (2007) Cetacean Distribution and Relative Abundance Survey during FSS Deep Water Survey Report to the Marine Institute, Oranmore, Wall D., O Brien J., Meade J. & Allen B.M. (2004) Summer Distribution and Relative Abundance of Cetaceans off the West Coast of Ireland. Final report to the Heritage Council, Kilkenny, Ireland. Wall D. (2007) Cetacean Distribution and Relative Abundance Survey during NIOZ Canyons Survey Report to the Royal Netherlands Institute for Sea Research and the Marine Institute, Oranmore, O Brien J. (2004) Cetacean Distribution and Relative Abundance Survey during FSS Northwest Herring Acoustic Survey Report to the Marine O Brien J. (2004) Cetacean Distribution and Relative Abundance Survey during FSS Blue Whiting Survey

10 2004. Report to the Marine Institute, Oranmore, Acoustic Survey Report to the Marine Wall D. (2004) Cetacean Distribution and Relative Abundance Survey during the Celtic Sea Herring

11 Appendix I: List of cetacean species recorded within the Irish EEZ and adjacent waters. Atlantic White-Sided Dolphin Lagenorhynchus acutus Beluga Delphinapterus leucas Blue Whale Balaenoptera musculus Bottlenose Dolphin Tursiops truncatus Common Dolphin Delphinus delphis Cuvier's Beaked Whale Ziphius cavirostris False Killer Whale Pseudorca crassidens Fin Whale Balaenoptera physalus Gervais Beaked Whale Mesoplodon europaeus* Harbour Porpoise Phocoena phocoena Humpback Whale Megaptera novaeangliae Killer Whale Orcinus orca Minke Whale Balaenoptera acutorostrata Northern Bottlenose Whale Hyperoodon ampullatus Northern Right Whale Eubalaena glacialis Pilot Whale (long-finned) Globicephala melas Pygmy Sperm Whale Kogia breviceps Risso's Dolphin Grampus griseus Sei Whale Balaenoptera borealis Sowerby's Beaked Whale Mesplodon bidens Sperm Whale Physeter macrocephalus Striped Dolphin Stenella coeruleoalba True's Beaked Whale Mesplodon mirus White-Beaked Dolphin Lagenorhynchus albirostris Vagrant * Recorded only from Stranding IWDG Ship Surveys Unit Page 1 13/07/2010