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Gilmour JP, Cook KL, Ryan NM, Puotinen ML, Green RH, Heyward AJ. A tale of two reef systems: Local conditions, disturbances, coral life histories, and the climate catastrophe. Ecol Appl 2022; 32:e2509. [PMID: 34870357 DOI: 10.1002/eap.2509] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 05/22/2021] [Accepted: 07/26/2021] [Indexed: 06/13/2023]
Abstract
Coral reefs have evolved over millennia to survive disturbances. Yet, in just a few decades chronic local pressures and the climate catastrophe have accelerated so quickly that most coral reefs are now threatened. Rising ocean temperatures and recurrent bleaching pose the biggest threat, affecting even remote and well-managed reefs on global scales. We illustrate how coral bleaching is altering reefs by contrasting the dynamics of adjacent reef systems over more than two decades. Both reef systems sit near the edge of northwest Australia's continental shelf, have escaped chronic local pressures and are regularly affected by tropical storms and cyclones. The Scott reef system has experienced multiple bleaching events, including mass bleaching in 1998 and 2016, from which it is unlikely to fully recover. The Rowley Shoals has maintained a high cover and diversity of corals and has not yet been impacted by mass bleaching. We show how the dynamics of both reef systems were driven by a combination of local environment, exposure to disturbances and coral life history traits, and consider future shifts in community structure with ongoing climate change. We then demonstrate how applying knowledge of community dynamics at local scales can aid management strategies to slow the degradation of coral reefs until carbon emissions and other human impacts are properly managed.
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Affiliation(s)
- James P Gilmour
- The Australian Institute of Marine Science, Indian Ocean Marine Research Centre, The University of Western Australia, Crawley, Western Australia, Australia
- Oceans Institute, University of Western Australia, Crawley, Western Australia, Australia
| | - Kylie L Cook
- The Australian Institute of Marine Science, Indian Ocean Marine Research Centre, The University of Western Australia, Crawley, Western Australia, Australia
| | - Nicole M Ryan
- The Australian Institute of Marine Science, Indian Ocean Marine Research Centre, The University of Western Australia, Crawley, Western Australia, Australia
| | - Marjetta L Puotinen
- The Australian Institute of Marine Science, Indian Ocean Marine Research Centre, The University of Western Australia, Crawley, Western Australia, Australia
| | - Rebecca H Green
- Oceans Institute, University of Western Australia, Crawley, Western Australia, Australia
- ARC Centre of Excellence for Coral Reef Studies, University of Western Australia, Crawley, Western Australia, Australia
| | - Andrew J Heyward
- The Australian Institute of Marine Science, Indian Ocean Marine Research Centre, The University of Western Australia, Crawley, Western Australia, Australia
- Oceans Institute, University of Western Australia, Crawley, Western Australia, Australia
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Wyatt M, Radford B, Callow N, Bennamoun M, Hickey S. Using ensemble methods to improve the robustness of deep learning for image classification in marine environments. Methods Ecol Evol 2022. [DOI: 10.1111/2041-210x.13841] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Mathew Wyatt
- The Australian Institute of Marine Science Indian Ocean Marine Research Centre, Fairway, Crawley 6009 Australia
- UWA School of Agriculture and Environment The University of Western Australia Crawley, Stirling Highway, WA 6009 Australia
| | - Ben Radford
- The Australian Institute of Marine Science Indian Ocean Marine Research Centre, Fairway, Crawley 6009 Australia
- UWA School of Agriculture and Environment The University of Western Australia Crawley, Stirling Highway, WA 6009 Australia
| | - Nikolaus Callow
- UWA School of Agriculture and Environment The University of Western Australia Crawley, Stirling Highway, WA 6009 Australia
| | - Mohammed Bennamoun
- UWA School of Computer Science and Software Engineering The University of Western Australia Crawley, Stirling Highway, WA 6009 Australia
| | - Sharyn Hickey
- UWA School of Agriculture and Environment The University of Western Australia Crawley, Stirling Highway, WA 6009 Australia
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Lester E, Langlois T, Lindgren I, Birt M, Bond T, McLean D, Vaughan B, Holmes TH, Meekan M. Drivers of variation in occurrence, abundance, and behaviour of sharks on coral reefs. Sci Rep 2022; 12:728. [PMID: 35031666 DOI: 10.1038/s41598-021-04024-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Accepted: 11/29/2021] [Indexed: 11/08/2022] Open
Abstract
Quantifying the drivers of population size in reef sharks is critical for the development of appropriate conservation strategies. In north-west Australia, shark populations inhabit coral reefs that border growing centres of human population, industry, and tourism. However, we lack baseline data on reef sharks at large spatial scales (hundreds of km) that might enable managers to assess the status of shark populations in the face of future development in this region. Here, we examined the occurrence, abundance and behaviour of apex (Galeocerdo cuvier, Carcharhinus plumbeus) and reef (C. amblyrhynchos, C. melanopterus, Triaenodon obesus) sharks using > 1200 deployments of baited remote underwater stereo-video systems (stereo-BRUVs) across > 500 km of coastline. We found evidence for species-specific influences of habitat and fishing activities on the occurrence (probability of observation), abundance (MaxN) and behaviour of sharks (time of arrival to the stereo-BRUVs and likelihood of feeding). Although the presence of management zoning (No-take areas) made little difference to most species, C. amblyrhynchos were more common further from boat ramps (a proxy of recreational fishing pressure). Time of arrival for all species was also influenced by distance to boat ramp, although patterns varied among species. Our results demonstrate the capacity for behavioural metrics to complement existing measures of occurrence and abundance in assessing the potential impact of human activities on shark populations.
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Langlois TJ, Wakefield CB, Harvey ES, Boddington DK, Newman SJ. Does the benthic biota or fish assemblage within a large targeted fisheries closure differ to surrounding areas after 12 years of protection in tropical northwestern Australia? Mar Environ Res 2021; 170:105403. [PMID: 34271482 DOI: 10.1016/j.marenvres.2021.105403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 06/22/2021] [Accepted: 06/25/2021] [Indexed: 06/13/2023]
Abstract
A large (~2450 km2) offshore (~75 km) targeted fisheries closure (TFC) area was implemented on the North West Shelf of Australia (NWS) in 1998 as part of a suite of management controls to address overfishing concerns, and in the process to potentially mitigate any impacts of trawling to benthic habitats. Twelve years later, the benthic biota and fish assemblages in the TFC were assessed using stereo-video and compared with adjacent areas that have been consistently fished with a range of commercial fishing methods. The remote nature of the region has meant that these areas would be inaccessible to recreational fishers. After 12 years of protection there were significant differences between the TFC and comparable fished areas in both the composition and the height of biogenic structures, however the magnitude of these differences were subtle, except for branching soft corals, which were significantly taller in the TFC area. Despite the relatively young age of the TFC, significant differences in the fish abundance and biomass compositions were driven by the slower growing, longer lived and inherently less productive fishery target species. The abundance of Lutjanus sebae (red emperor) and Epinephelus multinotatus (Rankin cod), and the associated biomass of L. sebae and Pristipomoides multidens (goldband snapper) were all greater within the TFC. However, neither the abundance or biomass of the relatively shorter lived and more productive fishery species (e.g. the bluespotted emperor Lethrinus punctulatus and the brownstripe snapper Lutjanus vitta) were greater within the TFC. Growth rates of benthic biota across the NWS are unknown, however the limited detectable differences in benthic biota between the TFC and fished areas, suggests that either recovery of the benthic biota is slow and may not yet be at a threshold for detection and/or alternatively that current fishing activities are not causing adverse impacts to biogenic structures. These large, offshore targeted fishery closures provide a useful reference point to examine the natural variability, growth and recovery of benthic biota and fish assemblages after the cessation of fishing.
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Affiliation(s)
- Tim J Langlois
- Western Australian Fisheries and Marine Research Laboratories, Department of Primary Industries and Regional Development, Government of Western Australia, P.O. Box 20, North Beach, WA, 6920, Australia; The UWA Oceans Institute and School of Biological Sciences, The University of Western Australia, 35 Stirling Highway, Crawley, WA, 6009, Australia.
| | - Corey B Wakefield
- Western Australian Fisheries and Marine Research Laboratories, Department of Primary Industries and Regional Development, Government of Western Australia, P.O. Box 20, North Beach, WA, 6920, Australia; School of Molecular and Life Sciences, Curtin University, GPO Box U1987, Perth, WA, 6845, Australia
| | - Euan S Harvey
- School of Molecular and Life Sciences, Curtin University, GPO Box U1987, Perth, WA, 6845, Australia
| | - Dion K Boddington
- Western Australian Fisheries and Marine Research Laboratories, Department of Primary Industries and Regional Development, Government of Western Australia, P.O. Box 20, North Beach, WA, 6920, Australia; School of Molecular and Life Sciences, Curtin University, GPO Box U1987, Perth, WA, 6845, Australia
| | - Stephen J Newman
- Western Australian Fisheries and Marine Research Laboratories, Department of Primary Industries and Regional Development, Government of Western Australia, P.O. Box 20, North Beach, WA, 6920, Australia; School of Molecular and Life Sciences, Curtin University, GPO Box U1987, Perth, WA, 6845, Australia
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