Hostname: page-component-586b7cd67f-t7fkt Total loading time: 0 Render date: 2024-11-24T05:03:26.996Z Has data issue: false hasContentIssue false

An analysis of dorsal edge markings in short-beaked common dolphins (Delphinus delphis) from the Bay of Gibraltar and the Moray Firth

Published online by Cambridge University Press:  11 August 2015

Connor Christian George Bamford
Affiliation:
Cetacean Research & Rescue Unit, PO Box 11307, Banff, Aberdeenshire AB45 3WB, UK
Kevin Peter Robinson*
Affiliation:
Cetacean Research & Rescue Unit, PO Box 11307, Banff, Aberdeenshire AB45 3WB, UK
*
Correspondence should be addressed to:K.P. Robinson, Cetacean Research & Rescue Unit, PO Box 11307, Banff, Aberdeenshire AB45 3WB, UK email: [email protected]

Abstract

In the present study, short-beaked common dolphins (Delphinus delphis L.) from the Bay of Gibraltar (GIB) and the Moray Firth (MF) were examined to document the relative frequency, distribution and shape of dorsal edge markings (DEMs) in the species and investigate potential causes for their occurrence. A dorsal fin layout system was used to map the relative positions and shapes of presenting DEMs along the anterior/posterior and upper/lower fin margin from 617 animals. A total of 1989 DEMs were extracted from the combined datasets, with individuals exhibiting between one and 11 nicks (median = 3). DEMs (in the form of tears, nicks, notches and indents) were primarily observed along the posterior trailing edges of fins, with the highest concentration being recorded in the upper region of the posterior fin (80.3%). Approximately 80% of all DEMs were round or rectangular in shape. Square (notched) and indented nick shapes were further recorded, but in significantly lower numbers. In contrast to all other nick shapes however, indented DEMs predominantly occurred along the anterior fin margin. Both natural and anthropogenic sources were implicated as causes of DEMs in the dataset. Interactions with fisheries were apparent in both GIB and MF animals and evidently present a threat to both populations. Indeed, the occurrence, prevalence and type of presenting DEM and/or fin injuries (e.g. missing fins or disfigurements) in the species may provide a useful measure of the type and intensity of fisheries interactions affecting different populations.

Type
Research Article
Copyright
Copyright © Marine Biological Association of the United Kingdom 2015 

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

Auger-Méthé, M. and Whitehead, H. (2007) The use of natural markings in studies of long-finned pilot whales (Globicephala melas). Marine Mammal Science 23, 7793.Google Scholar
Baird, R.W. and Gorgone, A.M. (2005) False killer whale dorsal fin disfigurements as a possible indicator of long-line fishery interactions in Hawaiian waters. Pacific Science 59, 593601.Google Scholar
Baird, R.W., Mahaffy, S.D., Gorgone, A.M., Cullins, T., McSweeney, D.J., Oleson, E.M., Bradford, A.L., Barlow, J. and Webster, D.L. (2015) False killer whales and fisheries interactions in Hawaiian waters: evidence for sex bias and variation among populations and social groups. Marine Mammal Science 31, 579590.Google Scholar
Baird, R.W. and Whitehead, H. (2000) Social organization of mammal-eating killer whales: group stability and dispersal patterns. Canadian Journal of Zoology 78, 20962105.Google Scholar
Bearzi, G. (2000) First report of a common dolphin (Delphinus delphis) death following penetration of a biopsy dart. Journal of Cetacean Research and Management 2, 217222.Google Scholar
Bearzi, G., Politi, E., Agazzi, S., Bruno, S., Costa, M. and Bonizzoni, S. (2005) Occurrence and present status of coastal dolphins (Delphinus delphis and Tursiops truncatus) in the eastern Ionian Sea. Aquatic Conservation: Marine and Freshwater Ecosystems 15, 243257.Google Scholar
Connor, R.C., Read, A.J. and Wrangham, R.W. (2000) Male reproductive strategies and social bonds. In Mann, J., Connor, R.C., Tyack, P.L. and Whitehead, H. (eds) Cetacean societies: field studies of dolphins and whales. Chicago, IL: University of Chicago Press, pp. 247269.Google Scholar
Corkeron, P.J., Morris, R.J. and Bryden, M.M. (1987) Interactions between bottlenose dolphins and sharks in Moreton Bay, Queensland. Aquatic Mammals 13, 109113.Google Scholar
Das, K., Lepoint, G., Loizeau, V., Debacker, V., Dauby, P. and Bouquegneau, J.M. (2000) Tuna and dolphin associations in the North-East Atlantic: evidence of different ecological niches from stable isotope and heavy metal measurements. Marine Pollution Bulletin 40, 102109.Google Scholar
De Boer, M.N., Leaper, R., Keith, S. and Simmonds, M.P. (2008) Winter abundance estimates for the common dolphin (Delphinus delphis) in the western approaches of the English Channel and the effect of responsive movement. Journal of Marine Animals and their Ecology 1, 1521.Google Scholar
Evans, P.G.H. and Hammond, P.S. (2004) Monitoring cetaceans in European waters. Mammal Review 34, 131156.Google Scholar
Frantzis, A. and Herzing, D.L. (2002) Mixed-species associations of striped dolphins (Stenella coeruleoalba), short-beaked common dolphins (Delphinus delphis), and Risso's dolphins (Grampus griseus) in the Gulf of Corinth (Greece, Mediterranean Sea). Aquatic Mammals 28, 188197.Google Scholar
Hammond, P.S., Mizroch, S.A. and Donovan, G.P. (1990) 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, 440 pp.Google Scholar
Herzing, D.L. (1996) Vocalizations and associated underwater behavior of free-ranging Atlantic spotted dolphins, Stenella frontalis, and bottlenose dolphins, Tursiops truncatus. Aquatic Mammals 22, 6179.Google Scholar
Jefferson, T.A., Stacey, P.J. and Baird, R.W. (1991) A review of killer whale interactions with other marine mammals: predation to co-existence. Mammal Review 21, 151180.CrossRefGoogle Scholar
Kato, H. (1984) Observation of tooth scars on the head of male sperm whales, as an indication of intra-sexual fighting. Scientific Reports of the Whales Research Institute 35, 3946.Google Scholar
Kirkwood, J.K., Bennet, P.M., Jepson, P.D., Kuiken, T., Simpson, V.R. and Baker, J.R. (1997) Entanglement in fishing gear and other causes of death in cetaceans stranded on the coasts of England and Wales. Veterinary Record 141, 9498.Google Scholar
Kiszka, J., Pelourdeau, D. and Ridoux, V. (2008) Body scars and dorsal fin disfigurements as indicators of interaction between small cetaceans and fisheries around the Mozambique Channel island of Mayotte. Western Indian Ocean Journal of Marine Science 7, 185193.Google Scholar
Kreb, D. (2004) Abundance of freshwater Irrawaddy dolphins in the Mahakam River in East Kalimantan, Indonesia, based on mark-recapture analysis of photo-identified individuals. Journal of Cetacean Research and Management 6, 269277.Google Scholar
Kuiken, T., Simpson, V.R., Allchin, C.R., Bennett, P.M., Codd, G.A., Harris, E.A., Howes, G.J., Kennedy, S., Kirkwood, J.K. and Law, R.J. (1994) Mass mortality of common dolphins (Delphinus delphis) in south west England due to incidental capture in fishing gear. Veterinary Record 134, 8189.Google Scholar
Long, D.J. and Jones, R.E. (1996) White shark predation and scavenging on cetaceans in the eastern North Pacific Ocean. In Klimley, A.P. and Ainley, D.G. (eds) Great white sharks: the biology of Carcharodon carcharias. San Diego, CA: Academic Press, pp. 293307.Google Scholar
MacLeod, C.D. (1998) Intraspecific scarring in odontocete cetaceans: an indicator of male ‘quality’ in aggressive social interactions? Journal of Zoology 244, 7177.Google Scholar
Marley, S.A., Cheney, B. and Thompson, P.M. (2013) Using tooth rakes to monitor population and sex differences in aggressive behaviour in bottlenose dolphins (Tursiops truncatus). Aquatic Mammals 39, 107115.Google Scholar
Morizur, Y., Berrow, S.D., Tregenza, N.J.C., Couperus, A.S. and Pouvreau, S. (1999) Incidental catches of marine-mammals in pelagic trawl fisheries of the northeast Atlantic. Fisheries Research 41, 297307.Google Scholar
Murphy, S., Collet, A. and Rogan, E. (2005) Mating strategy in the male common dolphin (Delphinus delphis): what gonadal analysis tells us. Journal of Mammalogy 86, 12471258.Google Scholar
Murphy, S., Winship, A., Dabin, W., Jepson, P.D., Deaville, R., Reid, R.J., Spurrier, C., Rogan, E., López, A., González, A.F., Read, F.L., Addink, M., Silva, M., Ridoux, V., Learmonth, J.A., Pierce, G.J. and Northridge, S.P. (2009) Importance of biological parameters in assessing the status of Delphinus delphis. Marine Ecology Progress Series 388, 273291.Google Scholar
Neumann, D.R., Leitenberger, A. and Orams, M.B. (2002a) Photo-identification of short beaked common dolphin (Delphinus delphis) in North-East New Zealand: a photo-catalogue of recognisable individuals. New Zealand Journal of Marine and Freshwater Research 36, 593604.Google Scholar
Neumann, D.R., Russell, K., Orams, M.B., Baker, C.S. and Duignan, P. (2002b) A new method for identifying mature male short-beaked common dolphins at sea, based on the presence of a postanal hump. Aquatic Mammals 28, 181187.Google Scholar
Read, A.J. (2008) The looming crisis: interactions between marine mammals and fisheries. Journal of Mammalogy 89, 541548.Google Scholar
Robinson, K.P. (2014) Agonistic intraspecific behavior in free-ranging bottlenose dolphins: calf-directed aggression and infanticidal tendencies by adult males. Marine Mammal Science 30, 381388.Google Scholar
Robinson, K.P., Eisfeld, S.M., Costa, M. and Simmonds, M.P. (2010) Short-beaked common dolphin (Delphinus delphis) occurrence in the Moray Firth, northeast Scotland. Marine Biodiversity Records 3, e55, 4 pp.Google Scholar
Robinson, K.P., O'Brien, J.M., Berrow, S.D., Cheney, B., Costa, M., Eisfeld, S.M., Haberlin, D., Mandleberg, L., O'Donovan, M., Oudejans, M.G., Ryan, C., Stevick, P.T., Thompson, P.M. and Whooley, P. (2012) Discrete or not so discrete: long distance movements by coastal bottlenose dolphins in UK and Irish Waters. Journal of Cetacean Research and Management 12, 365371.Google Scholar
Rommel, S.A., Pabst, D.A. and McLellan, W.A. (1993) Functional-morphology of the vascular plexuses associated with the cetacean uterus. Anatomical Record 237, 538546.Google Scholar
Rowe, L.E. and Dawson, S.M. (2009) Determining the sex of bottlenose dolphins from Doubtful Sound using dorsal fin photographs. Marine Mammal Science 25, 1934.Google Scholar
Scott, E.M., Mann, J., Watson-Capps, J.J., Sargeant, B.L. and Connor, R.C. (2005) Aggression in bottlenose dolphins: evidence for sexual coercion, male-male competition, and female tolerance through analysis of tooth-rake marks and behavior. Behavior 142, 2144.Google Scholar
Scott, M.D., Wells, R.S., Irvine, A.B. and Mate, B.R. (1990) Tagging and marking studies on small cetaceans. In Leatherwood, S. and Reeves, R.R. (eds) The bottlenose dolphin. New York, NY: Academic Press, pp. 489513.Google Scholar
Smuts, B.B. and Smuts, R.W. (1993) Male aggression and sexual coercion of females in nonhuman primates and other mammals: evidence and theoretical implications. Advances in the Study of Behavior 22, 163.Google Scholar
Stockin, K.A. and Visser, I.N. (2005) Anomalously pigmented common dolphins (Delphinus sp.) off northern New Zealand. Aquatic Mammals 31, 4351.Google Scholar
Tetley, M.J., Baumgartner, N., Björgvinsson, Á., Robinson, K.P. and Wald, E. (2007) A study comparing the position and morphology of minke whale dorsal fin edge marks between Scotland and Iceland. Paper presented at 17th Biennial Conference on the Biology of Marine Mammals, Cape Town, South Africa, 29 Nov–3 Dec 2007. http://www.crru.org.uk/publications.asp.Google Scholar
Thompson, P.M. and Hammond, P.S. (1992) The use of photography to monitor dermal disease in wild bottlenose dolphins (Tursiops truncatus). Ambio 21, 135137.Google Scholar
Urain, K.W., Hohn, A.A. and Hansen, L.J. (1999) Status of the photo-identification catalog of coastal bottlenose dolphins of the western North Atlantic. Beaufort, SC: NOAA Technical Memorandum.Google Scholar
Wedekin, L.L., Daura-Jorge, F.G. and Simões-Lopes, P.C. (2004) An aggressive interaction between bottlenose dolphins (Tursiops truncatus) and estuarine dolphins (Sotalia guianensis) in southern Brazil. Aquatic Mammals 30, 391397.Google Scholar
Wells, R.S. and Scott, M.D. (1997) Seasonal incidence of boat strikes on bottlenose dolphins near Sarasota, Florida. Marine Mammal Science 13, 475480.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