Blair Outhwaite has completed a year of study into the Hauraki Gulf’s bottlenose dolphins. He encountered many bottlenose dolphins last year, as his research took him around Whangaparaoa waters. Photos, Blair Outhwaite.
More than a year of fieldwork and a further year of writing resulted in Blair Outhwaite’s 181-page thesis called The Ecology of the Bottlenose dolphins in the Hauraki Gulf, which he completed last month.
Data was collected through Facebook, a dedicated research vessel and the local whale and dolphin watching boat (Auckland Whale and Dolphin Safari) around the Whangaparaoa and North Shore coastlines.
Among the focus points of Blair’s work was the contribution that citizen science – the observations of members of the community – could make to dolphin research.
Blair became aware of the Whale and Dolphin Watch Whangaparaoa Facebook page, which started in 2014. Here, members post photos of local sightings that became a resource for Blair’s studies (HM October 1, 2015).
He has dedicated a chapter of his thesis to citizen science, using the Facebook page as a key example.
“It is clear that citizen science has been really helpful in finding bottlenose dolphins, because they normally come close to the coastline,” he says. “The Facebook page gave us eyes and ears and photos that were helpful in identifying what species had been seen.”
He says since then, he and a colleague started a North Shore page and similar pages have been set up in East Auckland, Waiheke Island, Wellington and Dunedin.
“It definitely added to what people already knew about dolphin movements in the area,” he says.
“These groups have provided a large number of bottlenose dolphin reports in an area previously lacking dedicated surveys. The inner Hauraki Gulf is such a large area, but the Facebook page drew attention to more occurrences of bottlenose dolphins – these may have been missed or underrepresented in previous studies.”
He says earlier studies found that bottlenose dolphins were encountered most frequently in winter and autumn within the inner Hauraki Gulf, and the least in summer.
“The Facebook groups’ data detected a similar trend as most independent reports occurred in winter followed by spring and autumn. It is possible that bottlenose dolphins are using the inner Hauraki Gulf more frequently than what has been reported during autumn, winter and spring, but are not concentrated in a particular area and thus, more difficult to locate than in other parts of their range.”
He says that the distribution of bottlenose dolphins during summer appears to be concentrated towards the middle and northern areas of the inner Hauraki Gulf.
Travelling was the most recorded behavioural state, which is similar to other populations in New Zealand.
“It is possible that bottlenose dolphins use the Whangaparaoa and North Shore coastlines as a corridor to other foraging areas either within, or outside the inner Hauraki Gulf,” Blair says.
Now that his thesis is done and dusted, Blair is taking a break after more than six years of study for his Masters degree.
The absence of bottlenose dolphins from the study area during summer is expected given these results, as bottlenose dolphins are generally sighted in deeper waters, if at all, during summer periods and the Facebook sightings are largely limited to land based observations.