Summer Abundance of Harbour Porpoises (Phocoena phocoena) in the Coastal Waters of Iceland and the Faroe Islands
DOI:
https://doi.org/10.7557/3.4939Keywords:
harbour porpoise, abundance estimate, Iceland, Faroe Islands, aerial survey, distance sampling, cetaceanAbstract
This study presents the first fully corrected abundance estimates for the harbour porpoise (Phocoena phocoena) for Iceland and the Faroe Islands. In both regions reliable estimates are needed to assess the impact of by-catch and other threats to harbour porpoises. Aerial surveys with harbour porpoise as a secondary and main target species were conducted in the summers of 2007 and 2010 in Icelandic and in Faroese coastal waters respectively. In Iceland, the cue counting procedure was used (which also produces the data required for line transect analysis), while in the Faroese, standard line transect sampling was applied, following the SCANS-II (Small Cetacean Abundance in the North Sea) survey protocol. In both surveys, identical aircraft surveyed at an altitude of 600 ft and a speed of 90–100 kn. Only data collected during Beaufort Sea States (BSS) lower than 3 and during good or moderate porpoise sighting conditions were used for abundance estimates. Abundance estimates were corrected using stratified estimates of esw (incorporating g(0)) values derived during the SCANS-II survey in 2005 as principal observers took part in this survey as well. In Iceland, realised effort in good or moderate harbour porpoise sighting conditions totalled 8,289 km in 13 survey strata, where 77 sightings (109 individuals) were made by the experienced harbour porpoise observer only. In Faroese waters, only part of the area inside the 300 m depth curve could be surveyed and 1,564 km were surveyed in good or moderate porpoise sighting conditions, yielding 39 sightings (49 individuals). The total abundance estimates were 43,179 porpoises (CV=0.45; 95% CI: 31,755–161,899) for Icelandic coastal waters and 5,175 porpoises (CV=0.44; 95% CI: 3,457–17,637) for Faroese waters.
References
Astthorsson, O. S., Gislason, A. and Jonsson, S. (2007). Climate variability and the Icelandic marine ecosystem. Deep-Sea Research Part II: Topical Studies in Oceanography, 54(23–26), 2456–2477. https://doi.org/10.1016/j.dsr2.2007.07.030 https://doi.org/10.1016/j.dsr2.2007.07.030
Buckland, S. T., Anderson, D. R., Burnham, K. P., Laake, J. L., Borchers, D. L. and Thomas, L. (2001). Introduction to distance sampling. Estimating abundance of biological populations (S. T. Buckland Ed.). New York: Oxford University Press.
Burt, M. L., Borchers, D. L. and Samarra, F. (2006a). Aerial survey abundance estimates for harbour porpoise. Unpublished manuscript (In SCANSII (2008), Small Cetaceans in the European Atlantic and North Sea. Final report to the European Commission under project LIFE04NAT/GB/000245. Appendix D3.2).
Burt, M. L., Borchers, D. L. and Samarra, F. (2006b). Design-based abundance estimates from SCANS-II. Unpublished manuscript (In SCANSII (2008), Small Cetaceans in the European Atlantic and North Sea. Final report to the European Commission under project LIFE04NAT/GB/000245. Appendix D3.4).
Gunnlaugsson, T. and Sigurjónsson, J. (1990). Estimation of whale abundance based on observation made onboard Icelandic and Faroese survey vessels. Reports of the International Whaling Commission, 40, 571–5¬80.
Gilles, A., Scheidat, M. and Siebert, U. (2009). Seasonal distribution of harbour porpoises and possible interference of offshore wind farms in the German North Sea. Marine Ecology Progress Series, 383, 295–307. https://doi.org/10.3354/meps08020 https://doi.org/10.3354/meps08020
Gilles, A., Viquerat, S., Becker, E.A., Forney, K.A., Geelhoed, S.C. V, Haelters, J., … Aarts, G. (2016). Seasonal habitat-based density models for a marine top predator, the harbor porpoise, in a dynamic environment. Ecosphere, 7, e01367. https://doi.org/10.1002/ecs2.1367 https://doi.org/10.1002/ecs2.1367
Hammond, P. S., Benke, H., Berggren, P., Borchers, D. L., Buckland, S. T., Collet, A., … Øien, N. (1995). Distribution and abundance of harbour porpoises and other small cetaceans in the North Sea and adjacent waters. European Community LIFE Programme, Life, LIFE 92-2/IL/027, 240 pp. Retrieved from https://core.ac.uk/download/pdf/30844818.pdf
Hammond, P. S., Macleod, K., Berggren, P., Borchers, D. L., Burt, L., Cañadas, A., … Vázquez, J. A. (2013). Cetacean abundance and distribution in European Atlantic shelf waters to inform conservation and management. Biological Conservation, 164, 107–122. https://doi.org/10.1016/j.biocon.2013.04.010 https://doi.org/10.1016/j.biocon.2013.04.010
Hansen, R. G., Boye, T. K., Larsen, R. S., Nielsen, N. H., Tervo, O., Nielsen, R. D., … Heide-Jorgensen, M. P. (2019). Abundance of whales in West and East Greenland in summer 2015. NAMMCO Scientific Publications, 11. https://doi.org/10.7557/3.4689 https://doi.org/10.7557/3.4689
Hiby, A.R. and Hammond, P.S. (1989). Survey techniques for estimating current abundance and monitoring trends in abundance of cetaceans. Reports of the International Whaling Commission, (special issue 11), 47–80.
Hiby, L. (1999). The objective identification of duplicate sightings in aerial survey for porpoise. In G. W. Garner, S. C. Amstrup, J. L. Laake, B. F. J. Manly, L. L. McDonald and D. G. Robertson (eds.), Marine Mammal Survey and Assessment Methods, 179–189. Rotterdam: Balkema. https://doi.org/10.1201/9781003211167-17
Hiby, L. (2006). Effective strip width estimates from aerial survey data. Unpublished manuscript. In: SCANSII (2008). Small Cetaceans in the European Atlantic and North Sea. Final report to the European Commission under project LIFE04NAT/GB/000245. Appendix D3.1.
Hiby, L. and Lovell, P. (1998). Using aircraft in tandem formation to estimate abundance of harbour porpoise. Biometrics, 54(4), 1280–1289. https://doi.org/10.2307/2533658 https://doi.org/10.2307/2533658
Laake, J. L., Calambokidis, J., Osmek, S. D. and Rugh, D. J. (1997). Probability of detecting harbor porpoises from aerial surveys: estimating g(0). Journal of Wildlife Management, 61(1), 63–75. https://doi.org/10.2307/3802415 https://doi.org/10.2307/3802415
Larsen, B. H. (1995). A note on catches and exploitation of Harbour Porpoises (Phocoena phocoena L. 1758) around the Faroe Islands. Reports of the International Whaling Commission, (special Issue 16), 155–158.
Marine and Freshwater Research Institute (MFRI). (2019). Meðafli fugla og sjávarspendýra í grásleppuveiðum 2014-2018 [Bycatch of seabirds and marine mammals in lumpsucker gillnets 2014-2018]. Retrieved from https://www.hafogvatn.is/static/extras/images/medafli-fugla-og-spendyra-i-grasleppuveidum1158397.pdf
Marine and Freshwater Research Institute (MFRI). (2020, in press). Bycatch of marine mammals and seabirds in Icelandic waters 2016-2019. Unpublished manuscript (MFRI Tech Report).
Marsh, H. and Sinclair, D. F. (1989). Correcting for visibility bias in strip transect surveys of aquatic fauna. Journal of Wildlife Management, 53, 1017–1024. https://doi.org/10.2307/3809604 https://doi.org/10.2307/3809604
Mikkelsen, B. (2016). Fisheries in Faroese waters and the potential for by-catch of marine mammals. Unpublished manuscript (document NAMMCO/SC/23/BYC/05 for the North Atlantic Marine Mammal Commission).
North Atlantic Marine Mammal Commission (NAMMCO). (2018). Harbour porpoise. Retrieved from https://nammco.no/topics/harbour-porpoise/
North Atlantic Marine Mammal Commission and the Norwegian Institute of Marine Research (NAMMCO and IMR). (2019). Report of Joint IMR/NAMMCO International Workshop on the Status of Harbour Porpoises in the North Atlantic. Tromsø, Norway. Retrieved from https://nammco.no/wp-content/uploads/2020/03/final-report_hpws_2018_rev2020.pdf
Ólafsdóttir, D. (2010). Report on monitoring of marine mammal bycatch in Icelandic fisheries, Statistics for 2009 and review of previous information. Unpublished manuscript (document NAMMCO/SC17/16 for the North Atlantic Marine Mammal Commission).
Pálsson, Ó. K., Gunnlaugsson, T. and Ólafsdóttir, D. (2015). By-catch of seabirds and marine mammals in Icelandic Fisheries. Marine Research No. 178. Retrieved from https://www.hafogvatn.is/static/research/files/fjolrit-178.pdf
Pike, D. G., Paxton, C. G. M., Gunnlaugsson, T. and Víkingsson, G. A. (2009). Trends in the distribution and abundance of cetaceans from aerial surveys in Icelandic coastal waters, 1986-2001. NAMMCO Scientific Publications, 7, 117–142. https://doi.org/10.7557/3.2710 https://doi.org/10.7557/3.2710
Pike, D. G., Gunnlaugsson, T. and Víkingsson, G. A. (2010). Distribution and abundance of humpback whales in Icelandic coastal waters in summer 2007. Unpublished manuscript (document SC/62/O14 for the IWC Scientific Committee).
Pike, D. G., Gunnlaugsson, T., Mikkelsen, B., Halldórsson, S. D. and Víkingsson, G. (2019). Estimates of the abundance of cetaceans in the central North Atlantic based on the NASS Icelandic and Faroese shipboard surveys conducted in 2015. NAMMCO Scientific Publications, 11. https://doi.org/10.7557/3.4941 https://doi.org/10.7557/3.4941
Pike, D. G., Gunnlaugsson, T., Sigurjónsson J. and Víkingsson, G. A. (2020). Distribution and abundance of cetaceans in Icelandic waters over 30 years of aerial surveys. NAMMCO Scientific Publications, 11. https://doi.org/10.7557/3.4805 https://doi.org/10.7557/3.4805
Punt, A. E., Siple, M., Sigurðsson, G. M., Víkingsson, G., Francis, T. B., Granquist, S. M., … Moore, J. E. (2020). Evaluating management strategies for marine mammal populations: an example for multiple species and multiple fishing sectors in Iceland. Canadian Journal of Fisheries and Aquatic Sciences, 77(8), 1316–1331. https://doi.org/10.1139/cjfas-2019-0386 https://doi.org/10.1139/cjfas-2019-0386
Sigurjónsson, J. and Víkingsson, G. A. (1997). Seasonal abundance of the estimated food consumption by cetaceans in Icelandic and adjacent waters. Journal of Northwest Atlantic Fishery Science, 22, 271–287. https://doi.org/10.2960/J.v22.a20 https://doi.org/10.2960/J.v22.a20
Sigurjónsson, J., Gunnlaugsson, T. and Payne, M. (1989). NASS-87: Shipboard sightings surveys in Icelandic and adjacent waters June-July 1987. Report of the International Whaling Commission, 39, 395–409.
Scheidat, M., Gilles, A., Kock, K. and Siebert, U. (2008). Harbour porpoise Phocoena phocoena abundance in the southwestern Baltic Sea. Endangered Species Research, 5, 215–223. https://doi.org/10.3354/esr00161 https://doi.org/10.3354/esr00161
Teilmann, J. (2003). Influence of sea state on density estimates of harbour porpoises (Phocoena phocoena). Journal of Cetacean Research and Management, 5, 85–92. https://doi.org/10.47536/jcrm.v5i1.830
Thomas, L., Buckland, S. T., Rexstad, E. A., Laake, J. L., Strindberg, S., Hedley, S. L., … Burnham, K. P. (2010). Distance software: design and analysis of distance sampling surveys for estimating population size. Journal of Applied Ecology, 47(1), 5–14. https://doi.org/10.1111/j.1365-2664.2009.01737.x https://doi.org/10.1111/j.1365-2664.2009.01737.x
Víkingsson, G. A., Ólafsdóttir, D. and Sigurjónsson, J. (2003). Geographical and seasonal variation in the diet of harbour porpoises (Phocoena phocoena) in Icelandic coastal waters. NAMMCO Scientific Publications, 5, 243–270 https://doi.org/10.7557/3.2829 https://doi.org/10.7557/3.2829
Víkingsson, G. A., Ólafsdóttir, D. and Hauksson, E. (2004). Iceland – Progress report on marine mammal research in 2002. In NAMMCO Annual Report 2003, NAMMCO, Tromsø, 323–327. Retrieved from https://nammco.no/topics/annual-reports/
Víkingsson, G. A. andValdimarsson, H. (2006). Hvalir og umhverfisþættir [Whales and the environment]. Þættir úr vistfræði sjávar 2005 [Environmental conditions in Icelandic waters 2005]. Hafrannsóknastofnunin Fjölrit, 125, 30–33 [In Icelandic].
Víkingsson G. A., Elvarsson, B. Þ., Ólafsdóttir, D., Sigurjónsson, J., Chosson, V. and Galan, A. (2014). Recent changes in the diet composition of common minke whales (Balaenoptera acutorostrata) in Icelandic waters. A consequence of climate change? Marine Biology Research, 10, 138–152. https://doi.org/10.1080/17451000.2013.793812 https://doi.org/10.1080/17451000.2013.793812
Víkingsson, G. A., Pike, D. G., Valdimarsson, H., Schleimer, A., Gunnlaugsson, T., Silva, T., … Hammond, P. S. (2015). Distribution, abundance and feeding ecology of baleen whales in Icelandic waters: have recent environmental changes had an effect? Frontiers in Ecology and Evolution, 3, 1–18. https://doi.org/10.3389/fevo.2015.00006 https://doi.org/10.3389/fevo.2015.00006
Zerbini, A. N., Ward, E. J., Kinas, P. G., Engel, M. H. and Andriolo, A. (2011). A Bayesian Assessment of the conservation status of humpback whales (Megaptera novaeangliae) in the western Atlantic Ocean (Breeding Stock A). Journal of Cetacean Research and Management, 3, 131–144. https://doi.org/10.47536/jcrm.vi3.320
Downloads
Published
How to Cite
Issue
Section
License
Copyright (c) 2020 Anita Gilles, Thorvaldur Gunnlaugsson, Bjarni Mikkelsen, Daniel G. Pike, Gísli A. Víkingsson
This work is licensed under a Creative Commons Attribution 4.0 International License.
