{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,31]],"date-time":"2026-03-31T10:32:37Z","timestamp":1774953157496,"version":"3.50.1"},"reference-count":47,"publisher":"Canadian Science Publishing","issue":"4","license":[{"start":{"date-parts":[[2008,4,1]],"date-time":"2008-04-01T00:00:00Z","timestamp":1207008000000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/www.nrcresearchpress.com\/page\/about\/CorporateTextAndDataMining"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Can. J. Zool."],"published-print":{"date-parts":[[2008,4]]},"abstract":"<jats:p>In this study, we present for the first time a model for the social structure of Risso\u2019s dolphins ( Grampus griseus Cuvier, 1812). Over the period 2004\u20132006, 1028 Risso\u2019s dolphins were identified at Pico island, Azores. Individuals sighted on 10 or more occasions were included in the analysis of social structure (n = 183). High resighting rates indicate strong site fidelity for at least part of the population. We found that individuals form stable, long-term bonds organised in pairs or in clusters of 3\u201312 individuals. Social structure is stratified based on age and sex classes, with strong associations between adult males and between adult females. We suggest that clusters form the basic units of Risso\u2019s dolphin society. Thirteen pods consisting solely of adults, likely males, and 3 pods consisting of mother\u2013calf pairs were identified. Males are organised in stable, long-term associations of varying size that occur throughout the complete range of behavioural states observed. For females, associations can be of similar strength, but the time scale may vary depending on the presence of nursing calves. As subadults, associations also occur (pair formation), but are less stable than those observed for adults. We propose a new model for Risso\u2019s dolphin societies known as a stratified social organisation, which differs from the fission\u2013fusion and matrilineal society models.<\/jats:p>","DOI":"10.1139\/z07-138","type":"journal-article","created":{"date-parts":[[2008,4,1]],"date-time":"2008-04-01T19:18:42Z","timestamp":1207077522000},"page":"294-306","source":"Crossref","is-referenced-by-count":87,"title":["Social structure of Risso\u2019s dolphins (Grampus griseus) at the Azores: a stratified community based on highly associated social units"],"prefix":"10.1139","volume":"86","author":[{"given":"K. L.","family":"Hartman","sequence":"first","affiliation":[{"name":"Nova Atlantis Foundation, Rua Dr A.F. Pimentel 11, 9930-309 Santa Cruz das Ribeiras, Lajes do Pico, Pico island, Azores, Portugal."},{"name":"University of Amsterdam, Institute for Biodiversity and Ecosystem Dymanics, Nieuwe Achtergracht\u00a0127, 1018\u00a0WS Amsterdam, the Netherlands."},{"name":"Netherlands Organisation for Applied Scientific Research, Oude Waalsdorperweg\u00a063, 2597\u00a0AK Den Haag, the Netherlands."}]},{"given":"F.","family":"Visser","sequence":"additional","affiliation":[{"name":"Nova Atlantis Foundation, Rua Dr A.F. Pimentel 11, 9930-309 Santa Cruz das Ribeiras, Lajes do Pico, Pico island, Azores, Portugal."},{"name":"University of Amsterdam, Institute for Biodiversity and Ecosystem Dymanics, Nieuwe Achtergracht\u00a0127, 1018\u00a0WS Amsterdam, the Netherlands."},{"name":"Netherlands Organisation for Applied Scientific Research, Oude Waalsdorperweg\u00a063, 2597\u00a0AK Den Haag, the Netherlands."}]},{"given":"A. J.E.","family":"Hendriks","sequence":"additional","affiliation":[{"name":"Nova Atlantis Foundation, Rua Dr A.F. Pimentel 11, 9930-309 Santa Cruz das Ribeiras, Lajes do Pico, Pico island, Azores, Portugal."},{"name":"University of Amsterdam, Institute for Biodiversity and Ecosystem Dymanics, Nieuwe Achtergracht\u00a0127, 1018\u00a0WS Amsterdam, the Netherlands."},{"name":"Netherlands Organisation for Applied Scientific Research, Oude Waalsdorperweg\u00a063, 2597\u00a0AK Den Haag, the Netherlands."}]}],"member":"155","reference":[{"key":"atypb1\/ref1","doi-asserted-by":"crossref","first-page":"227","DOI":"10.1163\/156853974X00534","volume":"49","author":"Altmann J.","year":"1974","journal-title":"Behaviour"},{"key":"atypb2\/ref2","doi-asserted-by":"publisher","DOI":"10.1111\/j.1748-7692.2004.tb01146.x"},{"key":"atypb3\/ref3","doi-asserted-by":"publisher","DOI":"10.1126\/science.8480176"},{"key":"atypb4\/ref4","first-page":"201","volume":"37","author":"Arnbom T.","year":"1987","journal-title":"Rep. Int. Whal. 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U.K."},{"key":"atypb14\/ref14","first-page":"286","volume":"58","author":"Cockroft V.G.","year":"1993","journal-title":"Saeugetierkd. Mitt."},{"key":"atypb15\/ref15","unstructured":"Connor, R.C. 2000. Group living in whales and dolphins.InCetacean societies: field studies of dolphins and whales.Edited byJ. Mann, R.C. Connor, P.L. Tyack, and H. Whitehead. The University of Chicago Press, Chicago. pp.\u00a0199\u2013218."},{"key":"atypb16\/ref16","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.89.3.987"},{"key":"atypb17\/ref17","unstructured":"Connor, R.C., Wells, R.S., Mann, J., and Read, A.J. 2000. The bottlenose dolphin, social relationships in a fission\u2013fusion society.InCetacean societies: field studies of dolphins and whales.Edited byJ. Mann, R.C. Connor, P.L. Tyack, and H. Whitehead. The University of Chicago Press, Chicago. pp.\u00a091\u2013126."},{"key":"atypb18\/ref18","doi-asserted-by":"publisher","DOI":"10.1098\/rspb.2000.1357"},{"key":"atypb19\/ref19","doi-asserted-by":"publisher","DOI":"10.1111\/j.1748-7692.1998.tb00738.x"},{"key":"atypb20\/ref20","unstructured":"Evans, P.G.H. 1987. The natural history of whales and dolphins. Christopher Helm Ltd., Bromley, Kent, UK."},{"key":"atypb21\/ref21","first-page":"25","volume":"48","author":"Gannier A.","year":"1998","journal-title":"Vie Milieu"},{"key":"atypb22\/ref22","doi-asserted-by":"publisher","DOI":"10.1007\/s10592-006-9205-y"},{"key":"atypb23\/ref23","doi-asserted-by":"publisher","DOI":"10.1139\/z05-155"},{"key":"atypb24\/ref24","doi-asserted-by":"crossref","first-page":"219","DOI":"10.47536\/jcrm.v3i3.874","volume":"3","author":"Matthews J.N.","year":"2001","journal-title":"J. Cetacean Res. Manag."},{"key":"atypb25\/ref25","unstructured":"Heimlich-Boran, J.R. 1993. Social organization of the short-finned pilot whale,Globicephala macrorhynchus, with special reference to the comparative social ecology of delphinids. Ph.D. thesis, Department of Zoology, Cambridge University, Cambridge."},{"key":"atypb27\/ref27","unstructured":"Kruse, S., Leatherwood, S., Prematunga, W.P., Mendes, C., and Gamage, A. 1991. Records of Risso\u2019s dolphins,Grampus griseus, in the Indian Ocean, 1891\u20131986.InCetaceans and cetacean research in the Indian Ocean Sanctuary.Edited byS. Leatherwood and G. Donovan. United Nations Environmental Programme, Nairobi, Kenya. pp.\u00a066\u201377."},{"key":"atypb28\/ref28","unstructured":"Kruse, S., Caldwell, D.K., and Caldwell, M.C. 1999. Risso\u2019s dolphinGrampus griseus(G. Cuvier, 1812).InHandbook of marine mammals. Vol.\u00a06.Edited byS.H. Ridgway and R. Harrison. Academic Press, San Diego. pp.\u00a0183\u2013212."},{"key":"atypb29\/ref29","first-page":"951","volume":"77","author":"Leatherwood S.","year":"1980","journal-title":"Fish. Bull. (Wash. D.C.)"},{"key":"atypb30\/ref30","doi-asserted-by":"publisher","DOI":"10.1139\/z02-102"},{"key":"atypb31\/ref31","doi-asserted-by":"publisher","DOI":"10.1098\/rspb.1999.0644"},{"key":"atypb32\/ref32","doi-asserted-by":"publisher","DOI":"10.1111\/j.1469-7998.1998.tb00008.x"},{"key":"atypb33\/ref33","doi-asserted-by":"publisher","DOI":"10.1111\/j.1748-7692.1999.tb00784.x"},{"key":"atypb34\/ref34","unstructured":"Mortan, B., Britton, J.C., and De Frias Martins, A.M. 1998. Coastal ecology of the Azores. Sociedade Afonso Chaves, Ponta Delgada, Azores, Portugal."},{"key":"atypb35\/ref35","first-page":"111","volume":"36","author":"Olavarr\u00eda C.","year":"2001","journal-title":"Rev. Biol. Oceanogr."},{"key":"atypb36\/ref36","doi-asserted-by":"publisher","DOI":"10.1139\/z03-127"},{"key":"atypb37\/ref37","doi-asserted-by":"publisher","DOI":"10.1006\/jmsc.1997.0280"},{"key":"atypb38\/ref38","first-page":"97","volume":"6","author":"Perrin W.F.","year":"1984","journal-title":"Int. Whal. Comm. Spec. Issue"},{"key":"atypb39\/ref39","first-page":"259","volume":"11","author":"Ross G.J.B.","year":"1984","journal-title":"Ann. Cape Prov. Mus. Nat. Hist."},{"key":"atypb40\/ref40","doi-asserted-by":"publisher","DOI":"10.1111\/j.1748-7692.1986.tb00026.x"},{"key":"atypb41\/ref41","doi-asserted-by":"crossref","first-page":"38","DOI":"10.1163\/156853992X00101","volume":"123","author":"Smolker R.A.","year":"1992","journal-title":"Behaviour"},{"key":"atypb43\/ref42","unstructured":"Wells, R.S. 1991.The role of long-term study in understanding the social structure of a bottlenose dolphin community.InDolphin societies: discoveries and puzzles.Edited byK. Pryer and K.S. Norris. University of California Press, Berkeley. pp.\u00a0199\u2013225."},{"key":"atypb44\/ref43","doi-asserted-by":"publisher","DOI":"10.1007\/s002650050238"},{"key":"atypb45\/ref44","doi-asserted-by":"publisher","DOI":"10.1006\/anbe.1999.1099"},{"key":"atypb46\/ref45","unstructured":"Whitehead, H. 2003. Sperm whales: social evolution in the ocean. University of Chicago Press, Chicago."},{"key":"atypb48\/ref48","unstructured":"Whitehead, H., and Mann, J. 2000. Female reproductive strategies of cetaceans.InCetacean societies: field studies of dolphins and whales.Edited byJ. Mann, R.C. Connor, P.L. Tyack, and H. Whitehead. The University of Chicago Press, Chicago. pp.\u00a0219\u2013246."},{"key":"atypb49\/ref49","doi-asserted-by":"publisher","DOI":"10.1121\/1.399376"},{"key":"atypb50\/ref50","first-page":"43","volume":"12","author":"W\u00fcrsig B.","year":"1990","journal-title":"Rep. Int. Whal. Comm. Spec. 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