Research which analyses the DNA of New Zealand bottlenose dolphins may help with the long-term conservation of the species. Analysis of DNA inherited from dolphins’ mothers will reveal if there are any connections between different populations of dolphins here and around the Pacific Ocean.
This information would help with the management of the dolphins, Gabriela de Tezanos Pinto, a PhD student based at the University of Auckland’s School of Biological Sciences, said.
Three small and isolated populations had been identified in the coastal waters of New Zealand at Northland, Marlborough Sound and Fiordland.
“Compared with other dolphin populations in New Zealand, such as the dusky and Hector’s dolphins, bottlenoses are less abundant, are more isolated and have lower rates of reproduction,” Ms Pinto said.
This was a concern because the ability of a population to adapt and evolve to environmental change was determined by genetic variations.
The greater the variability in a gene pool the easier it was to adapt, evolve and survive, she said.
“Before my research, we didn’t know whether bottlenose dolphins represented one single robust population with individuals moving from one place to the other or whether they were three isolated and vulnerable populations,” Ms Pinto said.
“This is an important question for the long-term management of the species in New Zealand.”
The number of dolphins actively reproducing in Doubtful Sound was expected to be only about 20, fewer than the number of reproducing kakapos — a concern for the future of the population.
While the kapako and Hector’s dolphin had received a lot of attention and funding for conservation efforts because they were New Zealand native species, bottlenose dolphins could be found elsewhere in the world, she said.
“What is being overlooked is that New Zealand’s bottlenose dolphins have certain special characteristics which make them different from other populations in the world, and they need to be protected.”