scholarly journals Dugong (Dugong dugon) movements and habitat use in a coral reef lagoonal ecosystem

2020 ◽  
Vol 43 ◽  
pp. 167-181
Author(s):  
C Cleguer ◽  
C Garrigue ◽  
H Marsh
Keyword(s):  
Coral Reef ◽  
Large Scale ◽  
New Caledonia ◽  
Satellite Tracking ◽  
Barrier Reef ◽  
Straight Line ◽  
Tracking Time ◽  
Vast Range ◽  
Conservation And Management ◽  
Coral Reef Lagoons

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.

scholarly journals Diet composition of carnivorous fishes from coral reef lagoons of New Caledonia

2005 ◽  
Vol 18 (3) ◽  
pp. 231-250 ◽  
Author(s):  
Michel Kulbicki ◽  
Yves-Marie Bozec ◽  
Pierre Labrosse ◽  
Yves Letourneur ◽  
Gérard Mou-Tham ◽  
...  
Keyword(s):  
Coral Reef ◽  
Diet Composition ◽  
New Caledonia ◽  
Coral Reef Lagoons

scholarly journals Large‐scale, multidirectional larval connectivity among coral reef fish populations in the Great Barrier Reef Marine Park

2016 ◽  
Vol 25 (24) ◽  
pp. 6039-6054 ◽  
Author(s):  
David H. Williamson ◽  
Hugo B. Harrison ◽  
Glenn R. Almany ◽  
Michael L. Berumen ◽  
Michael Bode ◽  
...  
Keyword(s):  
Coral Reef ◽  
Great Barrier Reef ◽  
Reef Fish ◽  
Coral Reef Fish ◽  
Large Scale ◽  
Fish Populations ◽  
Barrier Reef ◽  
Marine Park ◽  
Larval Connectivity

Management of Water Quality in the Great Barrier Reef Marine Park

1989 ◽  
Vol 21 (2) ◽  
pp. 31-38 ◽  
Author(s):  
Simon Woodley
Keyword(s):  
Water Quality ◽  
Coral Reef ◽  
Great Barrier Reef ◽  
Barrier Reef ◽  
Management Issue ◽  
Reef System ◽  
Marine Park ◽  
World Heritage List ◽  
The World ◽  
Coral Reef System

The Great Barrier Reef is the largest coral reef system in the world. It is recognised and appreciated worldwide as a unique environment and for this reason has been inscribed on the World Heritage List. The Reef is economically-important to Queensland and Australia, supporting substantial tourism and fishing industries. Management of the Great Barrier Reef to ensure conservation of its natural qualities in perpetuity is achieved through the establishment of the Great Barrier Reef Marine Park. The maintenance of water quality to protect the reef and the industries which depend on it is becoming an increasingly important management issue requiring better knowledge and possibly new standards of treatment and discharge.

scholarly journals Stokes drift through corals

2021 ◽  
Author(s):  
Joseph J. Webber ◽  
Herbert E. Huppert
Keyword(s):  
Coral Reef ◽  
Coral Reefs ◽  
Porous Layer ◽  
Large Scale ◽  
Fluid Layer ◽  
Ocean Waves ◽  
Stokes Drift ◽  
Inviscid Fluid ◽  
Porous Bed ◽  
Vertical Drift

AbstractMotivated by shallow ocean waves propagating over coral reefs, we investigate the drift velocities due to surface wave motion in an effectively inviscid fluid that overlies a saturated porous bed of finite depth. Previous work in this area either neglects the large-scale flow between layers (Phillips in Flow and reactions in permeable rocks, Cambridge University Press, Cambridge, 1991) or only considers the drift above the porous layer (Monismith in Ann Rev Fluid Mech 39:37–55, 2007). Overcoming these limitations, we propose a model where flow is described by a velocity potential above the porous layer and by Darcy’s law in the porous bed, with derived matching conditions at the interface between the two layers. Both a horizontal and a novel vertical drift effect arise from the damping of the porous bed, which requires the use of a complex wavenumber k. This is in contrast to the purely horizontal second-order drift first derived by Stokes (Trans Camb Philos Soc 8:441–455, 1847) when working with solely a pure fluid layer. Our work provides a physical model for coral reefs in shallow seas, where fluid drift both above and within the reef is vitally important for maintaining a healthy reef ecosystem (Koehl et al. In: Proceedings of the 8th International Coral Reef Symposium, vol 2, pp 1087–1092, 1997; Monismith in Ann Rev Fluid Mech 39:37–55, 2007). We compare our model with field measurements by Koehl and Hadfield (J Mar Syst 49:75–88, 2004) and also explain the vertical drift effects as documented by Koehl et al. (Mar Ecol Prog Ser 335:1–18, 2007), who measured the exchange between a coral reef layer and the (relatively shallow) sea above.

scholarly journals Wind-induced variability in larval retention in a coral reef system: A biophysical modelling study in the South-West Lagoon of New Caledonia

2014 ◽  
Vol 122 ◽  
pp. 105-115 ◽  
Author(s):  
Marion Cuif ◽  
David Michael Kaplan ◽  
Jérôme Lefèvre ◽  
Vincent Martin Faure ◽  
Matthieu Caillaud ◽  
...  
Keyword(s):  
Coral Reef ◽  
New Caledonia ◽  
The South ◽  
Larval Retention ◽  
Reef System ◽  
System A ◽  
South West ◽  
Coral Reef System ◽  
Modelling Study ◽  
Biophysical Modelling

scholarly journals Remote sensing of <i>Trichodesmium</i> spp. mats in the western tropical South Pacific

2018 ◽  
Vol 15 (16) ◽  
pp. 5203-5219 ◽  
Author(s):  
Guillaume Rousset ◽  
Florian De Boissieu ◽  
Christophe E. Menkes ◽  
Jérôme Lefèvre ◽  
Robert Frouin ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Large Scale ◽  
New Caledonia ◽  
Hot Spot ◽  
Regional Scale ◽  
Atmospheric Correction ◽  
South Pacific ◽  
Aggregation Processes ◽  
Modis Imagery ◽  
Generate Surface

Abstract. Trichodesmium is the major nitrogen-fixing species in the western tropical South Pacific (WTSP) region, a hot spot of diazotrophy. Due to the paucity of in situ observations, remote-sensing methods for detecting Trichodesmium presence on a large scale have been investigated to assess the regional-to-global impact of this organism on primary production and carbon cycling. A number of algorithms have been developed to identify Trichodesmium surface blooms from space, but determining with confidence their accuracy has been difficult, chiefly because of the scarcity of sea-truth information at the time of satellite overpass. Here, we use a series of new cruises as well as airborne surveys over the WTSP to evaluate their ability to detect Trichodesmium surface blooms in the satellite imagery. The evaluation, performed on MODIS data at 250 m and 1 km resolution acquired over the region, shows limitations due to spatial resolution, clouds, and atmospheric correction. A new satellite-based algorithm is designed to alleviate some of these limitations, by exploiting optimally spectral features in the atmospherically corrected reflectance at 531, 645, 678, 748, and 869 nm. This algorithm outperforms former ones near clouds, limiting false positive detection and allowing regional-scale automation. Compared with observations, 80 % of the detected mats are within a 2 km range, demonstrating the good statistical skill of the new algorithm. Application to MODIS imagery acquired during the February-March 2015 OUTPACE campaign reveals the presence of surface blooms northwest and east of New Caledonia and near 20∘ S–172∘ W in qualitative agreement with measured nitrogen fixation rates. Improving Trichodesmium detection requires measuring ocean color at higher spectral and spatial (<250 m) resolution than MODIS, taking into account environment properties (e.g., wind, sea surface temperature), fluorescence, and spatial structure of filaments, and a better understanding of Trichodesmium dynamics, including aggregation processes to generate surface mats. Such sub-mesoscale aggregation processes for Trichodesmium are yet to be understood.

scholarly journals From Planning to Action: Forest Conservation and Management in Papua New Guinea

2000 ◽  
Vol 6 (4) ◽  
pp. 277 ◽  
Author(s):  
Kathy MacKinnon
Keyword(s):  
Papua New Guinea ◽  
Large Scale ◽  
Forest Conservation ◽  
Forest Products ◽  
New Guinea ◽  
Subsistence Agriculture ◽  
The Past ◽  
Language Groups ◽  
Eastern Half ◽  
Conservation And Management

Papua New Guinea (PNG) occupies the eastern half of the island of New Guinea and still boasts 33 million hectares of closed natural forest (77% of the country), home to numerous endemic species. Overall PNG is sparsely populated with some 700 distinct cultural/ language groups. Economic growth over the past two decades has been spurred by large-scale mining, petroleum and logging operations though the majority of the population continues to rely upon subsistence agriculture (swidden) and collection and utilization of forest products. Some 15 million hectares of forests are accessible for logging, of which 1.5 million hectares have already been logged, generally in an unsustainable manner. Of the over 6 million ha of approved timber blocks more than 1.5 million hectares have been located in areas of high biological value. Forest loss and degradation is now becoming a serious problem.

Sign in / Sign up

Export Citation Format

Share Document