Research digital skills training 2021
Publishing the Bay of Island Bottlenose dolphin catalogue
Associate Professor Rochelle Constantine, School of Biological Sciences & Institute of Marine Science.
Fig. 1 Field work in the Bay of Islands. MMEG Photo.
Scientists from the Marine Mammal Ecology Group (MMEG) at the University of Auckland led by Assoc. Prof. Rochelle Constantine have studied the population size, spatial distribution, social associations, habitat use, group demographics, genetics and impacts of tourism on the bottlenose dolphins of Northland since late 1993 (Figure 2). Most of their research on this species has focused on the Bay of Islands as this is the area with the most frequent sightings of dolphins and high levels of anthropogenic disturbance (Figure1). They also curate the Hauraki Gulf catalogue in collaboration with Massey University, and comparisons between the two catalogues have revealed ~60% of the dolphins use both locations.
Bottlenose Dolphin in the Bay of Island
Bottlenose dolphins are listed as Nationally Endangered (under the New Zealand Threat Classification System) as two of the three main populations, including the Bay of Islands dolphins, are declining (Baker et al. 2016, Tezanos-Pinto et al. 2013). The Bay of Islands is a special place for bottlenose dolphins because it provides food and sheltered bays to look after their young.
The numbers of bottlenose dolphins using the Bay of Islands have fallen by 65% since the late 1990s. Three quarters of all calves die before they become independent from their mums. The group don’t know what factors impact on the bigger picture for the local population –but impacts from boats has clearly been detrimental to this population (Constantine 2001, Constantine et al. 2004). Liz Hartel, an MSc graduate found a significant shift in dolphin habitat use over a 10-year period consistent with the decline in dolphins using the Bay from 1997-2005 (Hartel et al. 2014). The most recent abundance estimate by Olivia Hamilton, another MSc graduate, was around 50 dolphins with a dramatic shift in the social structure of the dolphins when they are in the Bay. In less than two decades, half the lifetime of a bottlenose dolphin, we have reduced the habitat quality in the Bay of Islands to the point that we have a significant population decline, complete shift in social structure and one of the highest calf mortality rates.
Figure 2. Bottlenose dolphins in the Bay of Islands. MMEG photo
Photo-identification and open science
As part of this research the MMEG have created a photo-identification catalogue containing a collection of uniquely identified bottlenose dolphin dorsal fin photos from the Bay of Islands, New Zealand collected between 1993 and 2013. Where possible there is a right and left side image of each dorsal fin. Photo-identification is a non-invasive technique using nicks and scarring patterns on the dorsal fin that is used to study social structure, distribution range, site fidelity, calving rates as well as habitat use and abundance.
Assoc. Prof. Constantine and the MMEG have worked with the Centre for eResearch to make the catalogue openly available using the University of Auckland’s Figshare repository (Figure 3). Figshare is a web-based platform that helps manage, disseminate research outputs. By publishing the catalogue and making it available to a larger audience the team hope to improve practice and scholarly communication. Openness and sharing of information are important aspects of working with publicly funded research money and to further our efforts in conservation and science. Publishing the collection allows discovery, easy access for others as well as a method to track views, downloads and other altmetrics. To date the catalogue has had 286 views, 528 downloads and 2 tweets since it was uploaded. For a closer look check out this link: https://t.co/0z2Y8NDPO7.
Figure 3. Bay of Islands bottlenose dolphin catalogue in the University of Auckland’s Figshare repository.