No Images? Click here Welcome to Māui Watch! Issue 7Summer 20162015/ 2016 Māui dolphin Abundance EstimateDuring the summer months of 2015 and 2016 boat surveys were carried out to monitor any changes in the Māui dolphin population on the west coast of the North Island. The survey was a joint effort between the Department of Conservation (DOC), Ministry for Primary Industries (MPI), University of Auckland, and Oregon State University, surveying dolphins between the Kaipara Harbour and the Mokau River. Figure 1. Māui dolphin seen during the 2016 DOC and University of Auckland survey. Photo: Andrew Wright Perhaps most interesting was that among the 51 individual dolphins sampled in 2015 and 2016, 49 were Māui dolphins and two were Hector’s dolphins (1 male, 1 female). Māui and Hector’s dolphins look identical, so genetic testing is the only way to tell them apart. This now brings the total number of Hector’s dolphins sampled alive or dead on the west coast of the North Island to seven. However, there is still no evidence of interbreeding between Hector’s and Māui dolphins. While this new abundance estimate appears to be higher than the 2010/11 estimate of 55 dolphins (95% CI 48-69), we need to treat the numbers with caution. The confidence intervals of both abundance estimates overlap which means we can’t say whether the dolphin population has increased or decreased over the past five years. What we can say is, the number of Māui dolphins is still critically low, and we must continue to manage their threats. Discussions within the Māui Research Advisory Group (Māui RAG) revealed an interest in undertaking an abundance survey of Māui dolphins every 5 years using the same capture-recapture DNA profiling method. Figure 2. Biopsy dart used in DNA profiling. Photo: Laura Boren Figure 3. Tissue sample collection method. Photo: Bryan Williams Have you seen me?ID: M023Last seen: Swimming in a pod of 6-8 dolphins during the 2015 summer field survey. M023 was first identified in 2011 and has been seen swimming between Manukau and 9 km south of Port Waikato. Recent sightings
Research updateResearch update: C-PODs 4-week Pilot program Hundreds of hours on boats and in the air, have provided invaluable information on dolphin pods, but there remain many questions. For example, how far offshore do the Māui dolphins go and how often? Also, where do they go in winter and at night? Finding answers is tricky; intensive year-round visual surveying is challenging and expensive. Yet, even intensive surveying may not be able to address all the issues as it is limited to periods of good weather and daylight. One option to fill the knowledge gaps is to use sound rather than sight. In February 2016 DOC, MPI and Auckland Council initiated a 4-week pilot program deploying two acoustic recorders (CPODs) in known Māui habitat. One was positioned in Manukau Harbour and the second was moored off Hamilton’s Gap. Unfortunately, Māui dolphins were not recorded on the Harbour deployment, but that was not unexpected given low detection rates from earlier studies. However, Māui dolphins were frequently recorded at the Hamilton’s Gap location, reaching peak average detection rates of almost once every 4 minutes coinciding with midday. Following this success, DOC and MPI are planning an offshore (out to 12nm) deployment of CPODs to see if we can hear how far offshore they go. Figure 4: DOC's 2016 C-Pod deployment. Photo: Scott Baker
Team Māui - Krista HupmanKrista Hupman is a DOC Marine Ranger in the Auckland District. The main focus of her job is the response, compliance and advocacy for marine wildlife and reserves. Her work in conservation ranges from education to marine wildlife management. Her extensive background in marine biology and 15 years of research experience has influenced her growing interest in working towards lessening human induced impacts on marine mammals. Q: How do you think we could raise the conservation profile of Māui dolphins within DOC and in the public? – Any ideas or perspectives? Within DOC – I think we can better utilise volunteers to raise the conservation profile. Organisations such as Project Jonah have several willing volunteers in many areas of the country who could contribute to raising awareness about Māui dolphins to reach a greater number of people. For the public - while traditional methods for awareness (i.e. boat ramp signs) might spark the interest of some people, they won’t target everyone. It’s for this reason in my role I am working towards more up to date methods to spread the word about these animals. I think apps to log sightings and social media messaging could be better used to reach wider audiences. Q: What are some of the positive things you see happening through the current protection measures? What else would you like to see? With current protection measures our research is showing the population hasn’t gone down – this is good! However, I still think there is a lot of work to do. I look forward to seeing the next Hector’s and Māui dolphin Threat Management Plan review which will take place in 2018. I also think we need to critically assess any negative effects to Māui dolphin populations within sanctuaries. Every dolphin counts and therefore we cannot afford to lose any. Māui and Hector’s Dolphin Sighting Phone AppWant to do your part and help us keep an eye on the Hector’s and Māui dolphin population? Well now you can, by downloading either the ‘Hector’s Dolphin Sightings’ app or the WWF ‘Maui's Dolphin’ app; free from Google Play and the App Store. These interactive apps will let you upload a photo, log your location and show you where other dolphins and whales were sighted. This community-based citizen science initiative can help scientists understand the distribution, movement and habitat use of dolphins and whales. |