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Estimating the abundance of the Hector's dolphins ( Cephalorhynchus hectori hectori ) that use Porpoise Bay, New ZealandNARA Subscribed
Hector's dolphin, an endangered species endemic to the coastal waters of Aotearoa New Zealand, has a highly fragmented population structure. Low abundance of some local subpopulations, coupled with a stepping‐stone mode of gene flow, suggests that these are at high risk of extinction. During the austral summer, dolphins from the small, genetically distinct subpopulation found along the South Island's south‐east coast frequentl...
Decadal stability in the distribution of bottlenose dolphins in Dusky Sound/Tamatea, New ZealandNARA Subscribed
Recreational use of wild spaces is increasingly popular, resulting in a burgeoning tourism industry. Such activities can degrade the environment and disrupt the behaviour and natural function of organisms. A small population of bottlenose dolphins ( Tursiops truncatus ) is resident in Dusky Sound, New Zealand, a fjord with increasing human use. Dolphins, as top predators, play an important role within ecosystems and are at ris...
The broadnose sevengill shark ( Notorynchus cepedianus ) is a large marine predator found in temperate coastal marine habitats. Despite being commonly encountered, details of its ecology are limited. To partially address this, we quantified the size and sex structure of N. cepedianus in Paterson Inlet, Stewart Island, New Zealand. A stereo‐camera baited underwater video system (BRUV) was deployed in a shallow coastal embayment...
Multi‐decadal observations of the size structure of sperm whales at Kaikōura, New ZealandNARA Subscribed
Measurements of body length play an important role in the assessment of size and population structure of whales, allowing estimation of population parameters such as age at sexual and physical maturity. Uniquely, sperm whales can be measured from the interpulse interval (IPI) of their echolocation clicks, which contain information on the length of the head, which is allometrically related to body length. Measurements of IPI we...
Aerial surveys of Hector's dolphins were carried out to evaluate the effectiveness of the Banks Peninsula Marine Mammal Sanctuary. In summer, the proportion of sightings inside the 4 nautical mile offshore boundary of the sanctuary was 79%. This dropped to just over 35% in winter. These estimates were used in a population viability analysis to determine whether the sanctuary needs to be extended to reduce dolphin bycatch to su...
Abundance, residency, and habitat utilisation of Hector's dolphins ( Cephalorhynchus hectori ) in Porpoise Bay, New ZealandNARA Subscribed
Theodolite tracking and boat‐based photo‐identification surveys were carried out in the austral summers of 1995/96 and 1996/97 to assess abundance, residency, and habitat utilisation of Hector's dolphins (Cephalorhynchus hectori van Beneden 1881) in Porpoise Bay, on the south‐east corner of the South Island of New Zealand. Data are consistent with the model of a small resident population that is visited occasionally by members...
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