Sustained Monitoring of Whales at South Georgia
This project is creating a long-term framework for monitoring whale numbers and behaviour.
Marine mammal expert and population biologist at BAS. Graduated at the University of Barcelona with a PhD on marine mammal population assessment. Research Associate at the NOAA Southwest Fisheries Science Center in La Jolla, CA (USA), before joining BAS.
I conducted field work and population assessments on marine mammals in the western Mediterranean, western Sahara, Eastern North Atlantic, North Sea, and Eastern Tropical Pacific. Since I joined BAS in 2002, I have spent 1006 days (2.76 years) over 15 different field seasons working on Antarctic fur seals, leopard seals, and elephant seals at Bird Island, South Georgia. I have also done a short field season in Svalbard, Ny Alesund, working on walruses.
I research how a range of marine mammals and seabirds in the Southern Ocean respond and adapt to increasing environmental fluctuation. Key components of this research focus upon food web interactions (e.g. energetic requirements, prey preferences), life history and population responses (e.g. intrinsic and environmental impacts, individual effects, genotypes), regional density and ecological impact of key species (e.g. seals and resource consumption in areas managed for fisheries) and anthropogenic impacts (e.g. climate change effects on the physical habitat of marine predators).
My specific work focuses:
Book Chapters:
FORCADA J (2021) Antarctic Fur Seal (Arctocephalus gazella, Peters 1875), In “Ecology and Conservation of Pinnipeds in Latin America” (G. Heckel, and Y. Schramm, eds). Springer, Cham. https://doi.org/10.1007/978-3-030-63177-2_4
FORCADA J (2018) Distribution, In “Encyclopedia of Marine Mammals” (Bernd Würsig, J.G.M. Thewissen, and Kit M. Kovacs, eds.), 3rd ed, pp. 259 – 262, Academic Press/Elsevier, San Diego, CA, USA.
FORCADA J, Staniland (2018) Antarctic fur seal Arctocephalus gazella, In “Encyclopedia of Marine Mammals” (Bernd Würsig, J.G.M. Thewissen, and Kit M. Kovacs, eds.), 3rd ed, pp. 25 – 27, Academic Press/Elsevier, San Diego, CA, USA.
Trathan P N, FORCADA J, Murphy E J (2012) Environmental forcing and Southern Ocean marine predator populations. In: Rogers, A. D., Johnston, N. M., Murphy, E. J., Clarke, A. eds. Antarctic Ecosystems: An Extreme Environment in a Changing World. Blackwell Publishing Ltd.
FORCADA J, Staniland I J. 2008. Antarctic fur seal. In: W. F. Perrin, Würsig, B., and Thewissen, H. G. M. eds., The Encyclopedia of Marine Mammals 2nd Edition. Academic Press-Elsevier.
FORCADA J. 2008 Distribution. In: W. F. Perrin, Würsig, B., and Thewissen, H. G. M. eds., The Encyclopedia of Marine Mammals 2nd Edition. Academic Press-Elsevier.
Gilmartin W G and FORCADA J (2008) Monk Seals (Monachus monachus, M. tropicalis, and M. schauinslandi). In: W. F. Perrin, Würsig, B., and Thewissen, H. G. M. eds., The Encyclopedia of Marine Mammals 2nd Edition. Academic Press-Elsevier.
FORCADA J. 2008. The Impact of Climate Change on Antarctic Megafauna. Impacts of Global Warming on Polar Ecosystems (ed Carlos M Duarte), pp. 83-108. Fundación BBVA, Madrid.
FORCADA J. 2007. El cambio climático y sus repercusiones para la megafauna antártica. Impactos del calentamiento global sobre los ecosistemas polares (ed Carlos M Duarte), pp. 83-110. Fundación BBVA, Madrid.
Trathan P N, Murphy E J, FORCADA J, Croxall J P, Reid K, Thorpe S E (2006) Physical forcing in the southwest Atlantic: ecosystem control. In Boyd I L, Wanless S, Camphuysen C J (eds) Top predators in Marine Ecosystems. Cambridge University Press, Cambridge, p 28-45.
Gazo M, FORCADA J, Aguilar A, Fernandez-Contreras M, Borrell A, Gonzalvo J and Tornero V (2004) Sector Norte (Cataluña e islas Baleares). In Raga J A, Pantoja J (eds) Proyecto Mediterraneo. Zonas de especial interes para la conservacion de los cetaceos en el Mediterraneo Español. Ministerio de Medio Ambiente, Naturaleza y Parques Nacionales, Serie Tecnica. Madrid, Spain, p 15-64.
Gilmartin W G and FORCADA J (2002) Monk Seals (Monachus monachus, M. tropicalis, and M. schauinslandi). In: W. F. Perrin, Würsig, B., and Thewissen, H. G. M. eds., The Encyclopedia of Marine Mammals. Academic Press.
FORCADA J (2002) Distribution. In: W. F. Perrin, Würsig, B., and Thewissen, H. G. M. eds., The Encyclopedia of Marine Mammals. Academic Press.
Aguilar A, FORCADA J, Gazo M and Badosa E (1997) Los cetáceos del Parque Nacional de Coiba. A: Flora y fauna del Parque Nacional de Coiba (Panamá). Agencia Española de Coperación Internacional, Madrid, Spain.
Aguilar A, Grau E, Borrell A, Calzada N and FORCADA J (1995) Dofí llistat, Stenella coeruleoalba. In: Els Grans Mamífers de Catalunya i Andorra. Coordinadors: Jordi Ruiz-Olmo and Alex Aguilar. Edicions Lynx, Barcelona, Spain.
Beaubrun P, Bayed A, Bompar J M, Boutiba Z, FORCADA J, Gannier A, Giordano A, Maigret J, Notarbartolo di Sciara G, Ozturk B and Ripoll T H (1995) Atlas préliminaire de distribution des cétacés de Méditerranée. Commission lnternationale pour I’Explotation Scientifique de la mer Méditerranée. Musée Océanographique, Monaco, France.
Technical Reports:
Silber G K, Lettrich M, Thomas P O, Baker J, Baumgartner M, Becker E A, Boveng P, Dick D, Fiechter J, FORCADA J, Forney K A, Griffis R, Hare J, Hobday A, Howell D, Laidre K, Mantua N, Quakenbush L, Santora J, Spencer P, Stock C, Stafford K, Sydeman W, Van Houtan K, Waples R. 2016. Report of a Workshop on Best Approaches and Needs for Projecting Marine Mammal Distributions in a Changing Climate. NOAA Technical Memorandum NMFS-OPR-54. http://www.nmfs.noaa.gov/pr/publications/techmemos.htm
Forcada, J. 2002. Multivariate methods for size-dependent detection in conventional line transect sampling. SWFSC Admin. Rep., La Jolla, LJ-02-07, 35 p. http://swfsc.nmfs.noaa.gov/IDCPA/TunaDol_rep/LJ_02_07.pdf
Gerrodette, T., and J. Forcada. 2002. Estimates of abundance of northeastern offshore spotted, coastal spotted, and eastern spinner dolphins in the eastern tropical Pacific Ocean. SWFSC Admin. Rep., La Jolla, LJ-02-06, 43 p. http://swfsc.nmfs.noaa.gov/IDCPA/TunaDol_rep/LJ_02_06.pdf
Gerrodette, T., and J. Forcada. 2002. Estimates of abundance of striped and common dolphins, and pilot, sperm and Bryde’s whales in the eastern tropical Pacific Ocean. SWFSC Admin. Rep., La Jolla, LJ-02-20, 24 p. http://swfsc.nmfs.noaa.gov/IDCPA/TunaDol_rep/LJ_02_20.pdf
Gerrodette, T., Watters, G. and Forcada, J. 2005. Preliminary estimates of 2003 dolphin abundance in the eastern tropical Pacific. SWFSC Admin. Rep., La Jolla, http://swfsc.nmfs.noaa.gov.
Conference Proceedings:
FORCADA, J., AGUILAR, A., EVANS, P.G.H. and PERRIN, W.F.1990. Distribution of Common and striped dolphins in the temperate waters of the Eastern North Atlantic. A: P.G.H. Evans, Aguilar, A and Smeenk, C. Ed: European Research on Cetaceans, 4: 64-66.
AGUILAR, R., PASTOR, X. and FORCADA, J. 1991. Results of the Greenpeace cetacean survey cruises during the Western Mediterranean striped dolphin epizootic. A: P.G.H. Evans. Ed: European research on cetaceans, 5: 18-21.
FORCADA J, Aguilar A, Hammond P, Pastor X and Aguilar R (1992) Striped dolphin abundance in the western Mediterranean basin after the 1990 epizootic. Pags.143-149. Proceedings of the Mediterranean Striped Dolphin Mortality International Workshop. Pastor, X. & Simmons, M. Ed. Greenpeace International. Mediterranean Sea Project. Palma de Mallorca.
FORCADA J, Aguilar A, Hammond P, Pastor X and Aguilar R (1992) Population estimate of striped dolphin inhabiting the Western Mediterranean sea. A: P.G.H. Evans. Ed: European Research on cetaceans, 6: 105-107.
FORCADA J, Aguilar A, Hammond P, Pastor X and Aguilar R (1994) Distribution and Abundance of fin whales in the Western Mediterranean Sea during the summer. A: P.G.H. Evans. Ed: European Research on Cetaceans, 7: 120-130.
Notarbartolo di Sciara G, FORCADA J, Acquarone M and Fabbri F (1994) Population estimates of fin whales and striped dolphins summering in the CorsoLigurian basin. A: P.G.H. Evans. Ed: European Research on Cetaceans, 7: 135-138.
FORCADA J, Aguilar A, Hammond P, Pastor X and Aguilar R (1995) Striped dolphin abundance in the north-western Mediterranean. A: P.G.H.Evans. Ed: European Research on Cetaceans, 8: 96-98.
Goujon M, FORCADA J and Desportes G (1995) Fin whale abundance in the eastern north Atlantic, estimated from the French program MICA-93 data. A: P.G.H. Evans. Ed: European Research on Cetaceans,8: 81-83.
FORCADA J (1995) Striped dolphin habitats in the north-western Mediterranean. A: P.G.H.Evans. Ed: European Research on Cetaceans, 8: 95.
FORCADA J (1996) Abundance of common and striped dolphins in the south-western Mediterranean. A: P.G.H.Evans. Ed: European Research on Cetaceans, 9: 153-155.
Cantos G, Samaranch R, Badosa E, Grau E, Forcada J and Aguilar (1997) Photo-identification catalogue of Mediterranean monk seals (Monachus monachus) from the western Sahara. P.G.H.Evans. Ed: European Research on Cetaceans, 11:300-301.
Aguilar A, FORCADA J, Arderiu A, Gazo M and Silvani L (1999) Status and conservation threats of small cetaceans in Spanish waters. P.G.H. Evans, J. Cruz and J. A. Raga Ed: European Research on Cetaceans, 13:75.
Gazo M, FORCADA J, Pastor T, Cantos G, Grau E and Aguilar A (1999) Status and conservation threats of small cetaceans in Spanish waters. P.G.H. Evans, J. Cruz and J. A. Raga Ed: European Research on Cetaceans, 13:377.
Aguilar A, FORCADA J, Arderiu A, Gazo M and Silvani L (1999) Status and conservation threats of small cetaceans in Spanish waters. P.G.H. Evans, J. Cruz and J. A. Raga Ed: European Research on Cetaceans, 13:75.
FORCADA J and Gerrodette T (2001) Improving abundance estimates from line transect surveys: modelling sighting conditions and school size distribution. P.G.H. Evans and E. O’Boyle Eds: European Research on Cetaceans, 15:420.
Forcada, J., Dunn, M., & Waluda, C. (2025). Seasonal sea ice concentration at Signy Island, South Orkney Islands, 1982-2024 (Version 1.0) [Data set]. NERC EDS UK Polar Data Centre. https://doi.org/10.5285/0283c3e4-2164-4dfb-a066-0c49b816d7b6
Fretwell, P., Bamford, C., Skachkova, A., Trathan, P., & Forcada, J. (2025). Model input and output statistics on fifteen-year assessment of emperor penguin breeding populations from the Bellingshausen sea to the Weddell sea from VHR satellite imagery, 2009-2023 (Version 1.0) [Data set]. NERC EDS UK Polar Data Centre. https://doi.org/10.5285/c8d8ffe6-0aff-493c-b40f-e63f0c35f081
Forcada, J. (2021). Counts of Antarctic fur seals from the special study beach at Bird Island South Georgia, from 1984 to 2019 (Version 1.0) [Data set]. NERC EDS UK Polar Data Centre. https://doi.org/10.5285/97acea13-b93d-4f3a-9cc7-f32e8df86cc0
Forcada, J. (2021). Antarctic Fur seal pup weight at Bird Island, South Georgia, from 1973 to 2020 (Version 1.0) [Data set]. NERC EDS UK Polar Data Centre. https://doi.org/10.5285/692fb625-ea99-4896-8354-b4da490535bb
Dunn, M., Nichol, C., Forcada, J., & Trathan, P. (2020). Population numbers and breeding success of Gentoo penguins (Pygoscelis papua) at Port Lockroy, Goudier Island, 1996 – 2020 (Version 1.0) [Data set]. UK Polar Data Centre, Natural Environment Research Council, UK Research & Innovation. https://doi.org/10.5285/92e92c14-0ff2-4ce2-8305-83d5b3a4071d
Staniland, I., Waluda, C., & Forcada, J. (2020). Platform Transmitting Terminal (PTT) tracking of Antarctic Fur Seals at Bird Island, South Georgia, from 1995 – 2010 (Version 1.0) [Data set]. UK Polar Data Centre, Natural Environment Research Council, UK Research & Innovation. https://doi.org/10.5285/224003cc-8f77-4980-8cac-5574e179e4f8
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