Abstract
Little is known about how the Vulnerable dugong Dugong dugon uses coral reef lagoons despite the importance of these habitats throughout much of its vast range. We used GPS satellite tracking systems to explore the space use of 12 dugongs at 3 locations in the coral reef lagoons of the main island of New Caledonia in the southwest Pacific: Cap Goulvain, Ouano and Nouméa. The movements of the tracked dugongs varied among individuals and all except one animal undertook large-scale movements (>15 km; mean [±SE] 37.7 ± 5.2 km) from their capture location (maximum waterway distance range: 13.8 to 72.9 km). The straight-line distances between the furthest GPS locations during each animal’s tracking period ranged from 21.3 to 74.5 km. We identified areas used intensively by dugongs in all 3 study areas, some of which were areas where seagrass presence has not been verified, or where dugongs have not been observed during past aerial surveys. Dugongs spent most of their tracking time within the lagoons, with 99.4% of GPS locations found inside the barrier reef. Nonetheless, where the lagoon was narrow and confined, 3 tracked dugongs used the fore reef shelf outside the barrier reef in the open ocean to commute between bays. Our findings can inform conservation and management initiatives in New Caledonia as well as other countries within the dugong’s range which have similar habitat geomorphology but where dugongs occur in numbers too low to be tracked and are considered Critically Endangered.
Highlights
Information on the space use of wildlife can help their conservation (Cooke 2008, Fraser et al 2018)
We explored the space use of dugongs in the coral reef lagoons of New Caledonia by deploying GPS satellite tracking devices on 12 adult dugongs
We explored the space use of the tracked dugongs in relation to a spatially explicit model of dugong density developed from data collected during aerial surveys conducted in New Caledonia in 2003, 2008, 2011 and 2012 (Cleguer et al 2015b)
Summary
Information on the space use of wildlife can help their conservation (Cooke 2008, Fraser et al 2018). It is important to study how wildlife, species with vast distribution ranges, use the various habitats within their range (Mayor et al 2009). The dugong is listed as Vulnerable to extinction at a global scale by the International Union for Conservation of Nature (Marsh & Sobtzick 2019). Its conservation prospects are variable across its vast distribution range. Marsh et al (2011) consider the species to be at high risk of local extinction in multiple parts of its range, including several island groups with fringing coral reefs, such as Palau and the Nansei Islands south of Japan
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.