Hostname: page-component-78c5997874-xbtfd Total loading time: 0 Render date: 2024-11-17T15:15:00.020Z Has data issue: false hasContentIssue false

Social structure of a population of bottlenose dolphins (Tursiops truncatus) in the oceanic archipelago of Madeira, Portugal

Published online by Cambridge University Press:  30 May 2017

Ana Dinis*
Affiliation:
Madeira Whale Museum, Caniçal, Madeira, Portugal University of Madeira, Faculty of Life Sciences, Madeira, Portugal CIIMAR/CIIMAR-Madeira, Interdisciplinary Centre of Marine and Environmental Research of Madeira, Edifício Madeira Tecnopolo, 9020-105, Funchal, Portugal
Filipe Alves
Affiliation:
Madeira Whale Museum, Caniçal, Madeira, Portugal CIIMAR/CIIMAR-Madeira, Interdisciplinary Centre of Marine and Environmental Research of Madeira, Edifício Madeira Tecnopolo, 9020-105, Funchal, Portugal
Cátia Nicolau
Affiliation:
Madeira Whale Museum, Caniçal, Madeira, Portugal
Cláudia Ribeiro
Affiliation:
Madeira Whale Museum, Caniçal, Madeira, Portugal CIIMAR/CIIMAR-Madeira, Interdisciplinary Centre of Marine and Environmental Research of Madeira, Edifício Madeira Tecnopolo, 9020-105, Funchal, Portugal
Manfred Kaufmann
Affiliation:
University of Madeira, Faculty of Life Sciences, Madeira, Portugal CIIMAR/CIIMAR-Madeira, Interdisciplinary Centre of Marine and Environmental Research of Madeira, Edifício Madeira Tecnopolo, 9020-105, Funchal, Portugal
Ana Cañadas
Affiliation:
ALNILAM– Research and Conservation, Madrid, Spain
Luís Freitas
Affiliation:
Madeira Whale Museum, Caniçal, Madeira, Portugal CIIMAR/CIIMAR-Madeira, Interdisciplinary Centre of Marine and Environmental Research of Madeira, Edifício Madeira Tecnopolo, 9020-105, Funchal, Portugal
*
Correspondence should be addressed to: A. Dinis, Madeira Whale Museum, Caniçal, Madeira, Portugal email: [email protected]

Abstract

In order to investigate social structure, 11 years of individual photo-identification data of bottlenose dolphin were analysed. We examined the type of association indices between pairs of identified individuals; the patterns of affiliation between individual dolphins and the probabilities of association between individuals over time. Between 2001 and 2012, there were 272 encounters which resulted in the identification of 501 individuals. The discovery curve resulting from the photo-identification analysis indicated an open population with regular recruitment of new individuals. All individuals were found to be associated at an association index of <0.05. A total of 291 individuals recorded from 2004 to 2012 were used to assess the temporal pattern of the social structure. The model fit to the Standardized Lagged Association Rate (SLAR) that best described the studied bottlenose dolphin population was ‘casual acquaintances’, and the analysis of associations over time showed a decreasing SLAR curve that falls until reaching the null rate, confirming random associations. The decline of the SLAR curve after ~500 days (1.4 years) suggests disassociation over that time period which can be explained by demographic events such as mortality or emigration. In an open ocean habitat like Madeira this is not unexpected, as there are neither geographic boundaries nor enclosed environments. This population presented a dynamic and fluctuating social structure, where groups change in size and composition. In future conservation efforts this population should be considered as one large community, where individuals associate, disassociate and reassociate with each other over time.

Type
Research Article
Copyright
Copyright © Marine Biological Association of the United Kingdom 2017 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Alves, F., Querouil, S., Dinis, A., Nicolau, C., Ribeiro, C., Freitas, L., Kaufmann, M. and Fortuna, C. (2013) Population structure of short-finned pilot whales in the oceanic archipelago of Madeira based on photo-identification and genetic analyses: implications for conservation. Aquatic Conservation: Marine and Freshwater Ecosystems 5, 758776.Google Scholar
Auger-Méthé, M. and Whitehead, H. (2007) The use of natural markings in studies of long-finned pilot whale (Globicephala melas). Marine Mammal Science 23, 7793.Google Scholar
Augusto, J.F., Rachinas-Lopes, P. and dos Santos, M.E. (2012) Social structure of the declining resident community of common bottlenose dolphins in the Sado Estuary, Portugal. Journal of the Marine Biological Association of the United Kingdom 92, 17731782.Google Scholar
Bedjer, L., Fletcher, D. and Bräger, S. (1998) A method for testing association patterns of social animals. Animal Behaviour 56, 719725.Google Scholar
Bridge, P. (1993) Classification. In Fry, J. (ed.) Biological data analysis: a practical approach. New York, NY: Oxford University Press, pp. 219242.Google Scholar
Burnham, K.P. and Anderson, D.R. (2002) Model selection and multimodel inference: a practical information-theoretic approach. New York, NY: Springer-Verlag.Google Scholar
Cairns, S.J. and Schwäger, S.J. (1987) A comparison of association indices. Animal Behaviour 35, 14541469.Google Scholar
Caldeira, R. and Sangrá, P. (2012) Complex geophysical wake flows: Madeira Archipelago case study. Ocean Dynamics 62, 683700.Google Scholar
Connor, R., Wells, R., Mann, J. and Read, A. (2000) The bottlenose dolphin: social relationships in a fission-fusion society. In Mann, J., Connor, R., Tyack, P.L. and Whitehead, H. (eds) Cetacean societies: field studies of dolphins and whales. Chicago, IL: University of Chicago Press, pp. 91126.Google Scholar
Costa, J. and Fitzgerald, T. (1996) Developments in social terminology: semantics battles in a conceptual war. Trends in Ecology Evolution 11, 285289.Google Scholar
Eisfield, S. and Robinson, K. (2004) The sociality of bottlenose dolphins in the outer Moray Firth NE Scotland: implications for current management proposals. Proceedings of the 18th Annual Conference of the European Cetacean Society, Kolmården, Sweden, 28–31 March.Google Scholar
Foley, A., MacGrath, D., Berrow, S. and Gerristsen, H. (2010) Social structure within the bottlenose dolphin (Tursiops truncatus) population in the Shannon Estuary, Ireland. Aquatic Mammals 36, 372381.Google Scholar
Geldmacher, J., Van Den Bogaard, P., Hoernle, K. and Schmincke, H. (2000) The 40Ar/39Ar age dating of the Madeira Archipelago and hotspot track (eastern North Atlantic). Geochemistry Geophysics Geosystems 1, 1999GC000018.Google Scholar
Ginsberg, J.R. and Young, T.P. (1992) Measuring association between individuals or groups in behavioural studies. Animal Behaviour 44, 377379.Google Scholar
Greiller, S., Hammond, P.S., Wilson, B., Sanders-Reed, C.A. and Thompson, P.M. (2003) Use of photo-identification data to quantify mother-calf association patterns in bottlenose dolphins. Canadian Journal of Zoology 81, 14211427.Google Scholar
Hoelzel, A., Potter, C. and Best, P. (1998) Genetic differentiation between parapatric ‘nearshore’ and ‘offshore populations of the bottlenose dolphin. Proceedings of the Royal Society Series B, Biological Sciences 265, 11771183.Google Scholar
Louis, M., Viricel, A., Luca, T., Peltier, H., Alfonsi, E., Berrow, S., Brownlow, A., Covelo, P., Dabin, W., Deaville, R., de Stephanis, R., Gally, F., Gauffier, P., Penrose, R., Silva, M.A., Guinet, C. and Simon-Bouhet, B. (2014) Habitat-driven population structure of bottlenose dolphins, Tursiops truncatus, in the North-East Atlantic. Molecular Ecology 23, 857874.Google Scholar
Lusseau, D., Schneider, K., Boisseau, O.J., Haase, P., Slooten, E. and Dawson, S. (2003) The bottlenose dolphin community of Doubtful Sound features a large porportion of long-lasting associations: can geographic isolation explain this unique trait? Behavioral Ecology and Sociobiology 54, 396405.Google Scholar
Lusseau, D., Williams, R.J., Wilson, B., Grellier, K., Barton, T.R., Hammond, P.S. and Thompson, P.M. (2004) Parallel influence of climate on the behaviour of Pacific killer whales and Atlantic bottlenose dolphins. Ecology Letters 7, 10681076.Google Scholar
Lusseau, D., Wilson, B., Hammond, P.S., Grellier, K., Durban, J.W., Parsons, K.M., Barton, T.R. and Thompson, P.M. (2006) Quantifying the influence of sociality on population structure in bottlenose dolphins. Journal of Animal Ecology 75, 1424.Google Scholar
Manly, B. (1995) A note on the analysis of species co-occurrences. Ecology 76, 11091115.Google Scholar
Mann, J., Connor, R.C.L., Barre, M. and Heithaus, M.R. (2000) Female reproductive success in bottlenose dolphins (Tursiops sp.): life history, habitat, provisioning, and group-size effects. Behavioral Ecology 11, 210219.Google Scholar
Maze-Foley, K. and Würsig, B. (2002) Patterns of social affiliation and group composition for bottlenose dolphins (Tursiops truncatus) in San Luis Pass, Texas. Gulf of Mexico Science 20, 122134.Google Scholar
Merriman, M.G. (2007) Abundance and behavioural ecology of bottlenose dolphins (Tursiops truncatus) in the Marlborough Sounds, New Zealand. Master's thesis, Massey University, New Zealand.Google Scholar
Newman, M. (2004) Analysis of weighted networks. Physical Review E70, 056131.Google Scholar
Quérouil, S., Silva, M.A., Freitas, L., Prieto, R., Magalhães, S., Dinis, A., Alves, F., Matos, J.A., Mendonça, D., Hammond, P. and Santos, R.S. (2007) High gene flow in oceanic bottlenose dolphins (Tursiops truncatus) of the North Atlantic. Conservation Genetics 8, 14051419.Google Scholar
Silva, M.A., Prieto, R., Magalhães, S., Seabra, M.I., Santos, R.S. and Hammond, P.S. (2008) Ranging patterns of bottlenose dolphins living in oceanic waters: implications for population structure. Marine Biology 179, 179192.Google Scholar
Slooten, E., Dawson, S.M. and Whitehead, H. (1993) Associations among photographically identified Hector's dolphins. Canadian Journal of Zoology 71, 13111328.Google Scholar
Smolker, R., Richards, A., Connor, R.C. and Pepper, J.W. (1992) Sex differences in patterns of association among Indian Ocean bottlenose dolphins. Behaviour 123, 3869.Google Scholar
Stevick, P.T., Palsbøll, P.J., Smith, T.D., Bravington, M.V. and Hammond, P.S. (2001) Errors in identification using natural markings: rates, sources, and effects on capture-recapture estimates of abundance. Canadian Journal of Fisheries and Aquatic Science 58, 18611870.Google Scholar
Wells, R. (1991) The role of long-term study in understanding the social structure of a bottlenose dolphin community. In Pryor, K. and Norris, K. (eds) Dolphin societies: discoveries and puzzles. Berkeley, CA: University of California Press, pp. 199225.Google Scholar
Wells, R. (1986) Population structure of bottlenose dolphins along the central west coast of Florida. Southeast Fisheries Center: Contract Report to National Marine Fisheries Service.Google Scholar
Wells, R., Rhinehart, H., Cunningham, P., Whaley, J., Baran, M., Koberna, C. and Costa, D. (1999) Long distance offshore movements of bottlenose dolphins. Marine Mammal Science 15, 10981114.Google Scholar
Wells, R., Scott, M., Irvine, A. (1987) The social structure of free-ranging bottlenose dolphins. In Genoways, H. (ed.) Current mammalogy. New York, NY: Plenum Press, pp. 247305.Google Scholar
Whitehead, H. (1995) Investigating structure and temporal scale in social organizations using identified individuals. Behavior Ecology 6, 199208.Google Scholar
Whitehead, H. (1999) Testing association patterns of social animals. Animal Behaviour 57, 2629.Google Scholar
Whitehead, H. (2007) Selection of models of lagged identification rates and lagged association rates using AIC and QAIC. Communication in Statistics – Simulation and Computation 36, 12331246.Google Scholar
Whitehead, H. (2008) Analyzing animal societies: quantitative methods for vertebrate social analysis. Chicago, IL: University of Chicago Press.Google Scholar
Whitehead, H. (2009) SOCPROG programs: analysing animal social structures. Behavioral Ecology and Sociobiology 63, 765778.Google Scholar
Whitehead, H. and Dufault, S. (1999) Techniques for analysing vertebrate social structure using identified individuals: review and recommendations. Advances in the Study of Behavior 28, 3374.Google Scholar
Whitehead, H. and Van Parijs, S. (2010) Studying marine mammal social systems. In Boyd, I., Don Bowen, W. and Iverson, S. (eds) Marine mammal ecology and conservation: a handbook of techniques. New York, NY: Oxford University Press, pp. 263282.Google Scholar
Wilson, D. (1995) The ecology of bottlenose dolphins in the Moray Firth, Scotland: a population at the northern extreme of the species’ range. PhD thesis, Aberdeen University, Aberdeen, Scotland.Google Scholar
Wilson, E.O. (1975) Sociobiology: the new synthesis. Cambridge, MA: Belknap Press.Google Scholar
Würsig, B. and Jefferson, T. (1990) Methods of photo-identification for small cetaceans. In Hammond, P.S., Mizroch, S.A. and Donovan, G.P. (eds) Individual recognition of cetaceans: use of photo-identification and other techniques to estimate population parameters. Report of the International Whaling Commission, special issue 12. Cambridge: International Whaling Commission, pp. 4352.Google Scholar
Würsig, B. and Würsig, M. (1977) The photographic determination of group size, composition and stability of coastal porpoises (Tursiops truncatus). Science 198, 755756.Google Scholar