TriOceans has spent 8 years curating a photoID catalogue for bottlenose dolphin in Far North Waters and can track how the population parameters evolve.
PhotoID (short for photo identification) is used by researchers to track bottlenose dolphin movements, social networks and habitat preferences. Each fin is unique like a human fingerprint, enabling individual movements to be tracked with minimal disturbance.
Dolphin acoustics
Dolphins communicate with whistles, clicks and buzzes. In a world where visibility is rarely more than a few meters, sound is the way to go to find each other… or other species!
Similarly to bats, dolphins use echolocation to precisely detect their prey. That is the reason behind their bulbous head: a sac of oil called the melon helps produce their whistles and clicks.
Little is known about the significance of each sound… however, we do know dolphins use something similar to a name: the “signature whistle”. Each individual dolphin has its own signature whistle, and calves will often imitate their mothers’, with their own unique tempo of course!
Markov chains are used to assess how the behaviour of marine mammals changes across a range of variables (depth, group size, presence of calves or vessels…). Results indicate bottlenose dolphins spend less time feeding and resting, but more time milling and socialising in the presence of vessels. This work follows from a Massey unviersity study conducted in 2016 – https://www.doc.govt.nz/globalassets/documents/conservation/marine-and-coastal/bottlenose-responses-dolphin-vessel-activity-northland.pdf
Kernel density maps of little blue penguins in the Bay of Islands
The TriOceans team drives pre-planned transect lines to cover Far North waters evenly whilst searching for target species. This allows for reliable population and distribution estimates. Amongst those recorded are the little blue penguin, allowing us to build an 8 year database of their daytime movements.
Little blue penguins are found throughout Far North waters, yet they remain largely unstudied
TriOceans