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dc.contributor.advisorDawson, Stephen Michael
dc.contributor.authorBrough, Tom Evan
dc.date.available2013-11-21T01:51:33Z
dc.date.copyright2013
dc.identifier.citationBrough, T. E. (2013). Using photography to study the conservation biology of bottlenose dolphins in southern New Zealand. (Thesis, Master of Science). University of Otago. Retrieved from http://hdl.handle.net/10523/4480en
dc.identifier.urihttp://hdl.handle.net/10523/4480
dc.description.abstractPhotography is a key tool in conservation science and has numerous applications. In the present study, photography and photogrammetry are used to provide new abundance estimates for the populations of Doubtful and Dusky Sounds, and to determine potential causes of the dramatic variation in reproductive success of females in Doubtful Sound. Additionally, this thesis aims to document the presence of an unstudied population of bottlenose in the Stewart Island area. Mark-recapture analyses of photo-ID data show that bottlenose dolphin abundance in Doubtful and Dusky Sounds for 2012 were 61 (CV=0.5%) and 116 (CV=0.2%) respectively. Both populations underwent a decline between 2011 and 2012, and have a history of previous declines. To aid our understanding of the causes of these declines, a stereo-photogrammetric system was built, and calibrated, to measure dolphins in the field. Repeated measurements of all individuals within the population of Doubtful Sound produced a mean CV of 2.43%. Analysis of a range of factors potentially influencing calf survival showed that survival to 1 year depended primarily on being born at the optimum time (January). Survival to 3 years was predicted by the size of the mother (larger=higher calf survival) and the sea water temperature at birth (warmer=higher calf survival). Frequent reports of sightings suggested the presence of a previously unstudied population inhabiting the south-coast coast of the South Island. Surveys of Paterson Inlet, Stewart Island resulted in an abundance estimate of 18 (95%CI= 15-20) regular users of the area. Results from this thesis indicate that the Fiordland populations are still vulnerable to population decline, and provide insight on why this is so. The repeated observation of dolphins at Stewart Island provides new information as to the distribution and abundance of this threatened species in NZ waters.
dc.format.mimetypeapplication/pdf
dc.language.isoen
dc.publisherUniversity of Otago
dc.rightsAll items in OUR Archive are provided for private study and research purposes and are protected by copyright with all rights reserved unless otherwise indicated.
dc.subjectconservation
dc.subjectdolphins
dc.subjectFiordland
dc.subjectNew Zealand
dc.titleUsing photography to study the conservation biology of bottlenose dolphins in southern New Zealand.
dc.typeThesis
dc.date.updated2013-11-21T00:34:14Z
dc.language.rfc3066en
thesis.degree.disciplineMarine Science
thesis.degree.nameMaster of Science
thesis.degree.grantorUniversity of Otago
thesis.degree.levelMasters
otago.openaccessOpen
otago.evidence.presentYes
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