The South-west Marine Region comprises Commonwealth waters and seabed from the eastern end of Kangaroo Island, South Australia, to 70 km offshore from Shark Bay, Western Australia. Inshore, the region is delineated by the outer jurisdictional boundary limit of the state waters of South Australia and Western Australia, while offshore it is delineated by Australia’s exclusive economic zone boundary. The South-west Marine Region is adjacent to, but does not cover, the state waters of South Australia and Western Australia, including waters adjacent to the Houtman Abrolhos Islands. The South-west Marine Region is generally characterised by low levels of nutrients and high species biodiversity, including a large number of endemic species. The flora and fauna of the region are a blend of tropical, subtropical and temperate species. Temperate species dominate the southern and eastern parts of the region, while tropical species become progressively more
South West Marine Region
Government evidence of impact of climate change:
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Australian Government Marine bioregional plan for the South West Marine Region
Right now; our iconic marine environment is coming under more and more pressure from industry; from pollution and; increasingly; from climate change.
Green turtle Change in oceanography (climate change) Leatherback turtle Loggerhead turtle The strength of the Leeuwin Current has decreased slightly since the 1970s.
Interactions with fisheries may increase as a result of possible changes to the turtles’ distributions as climate change progresses.
Longer term predictions estimate increases of 0.5 m to 1 m by 2100; relative to levels (Climate Commission 2011).
Sea levels are currently rising at near the upper end of current projections and will continue to rise in response to increasing concentrations of greenhouse gases.
Longer term predictions estimate increases of 0.5 to 1m by 2100; relative to 2000 levels (Climate Commission 2011).
There is also evidence from the region of latitudinal shifts in distribution; and these have been attributed to climate related changes (Dunlop 2009).
Longer term predictions estimate increases of 0.5 m to 1 m by 2100; relative to levels (Climate Commission 2011).
Short tailed shearwater Fairy tern Black faced cormorant Changes in sea temperature (climate change) Indian yellow nosed albatross Great winged petrel Soft plumaged petrel Sea surface temperatures around Australia are expected to increase by 1 2 C by 2030 and 2 3 C by 2070 (Hobday et al. 2006).
White faced storm petrel Flesh footed shearwater Black faced cormorant All species Ocean acidification (climate change) Driven by increasing levels of atmospheric Co; and subsequent chemical changes in the ocean; acidification is already underway and detectible.
Longer term predictions estimate increases of 0.5 to 1m by 2100; relative to levels (Climate Commission 2011).
There are a number of productivity hotspots in the region that may be affected by climate related changes; including the Western Eyre and Kangaroo Island upwelling.
Habitat degradation as a result of coastal development or climate related increases in coastal and inshore erosion may affect this vulnerable species.
Potential pressures on ecosystem functioning and integrity of this key ecological feature include commercial and recreational fishing; which may lead to overexploitation of important species (considered in Schedule 1) activities associated with coastal and marine infrastructure development; which have the potential to impact on water quality; and increase the risk of oil spill; chemical contamination and nutrient pollution onshore or offshore construction or dredging which results in habitat modification climate change.
Potential pressures on ecosystem functioning and integrity of this key ecological feature include noise generating activities; which might affect large whales that use these habitats (these are considered in Schedule 2.5) bycatch and extraction of living resources ; potentially leading to overexploitation of important species increased shipping traffic that might increase the likelihood of oil spill and chemical contamination and of ship strike for megafauna aggregating in the area (these are considered in Schedule 2.5) changes to oceanographic processes that are linked to localised productivity; and potential changes to community structure arising from shifts in marine species distribution as a result of climate change.
Seagrass meadows occur in more sheltered areas and in the inter reef lagoons along exposed sections of the coast Potential pressures on ecosystem functioning and integrity of this key ecological feature include coastal and marine infrastructure development and associated changes in water quality (oil; chemical and nutrient pollution; turbidity) development of offshore aquaculture and other marine infrastructure; which might adversely affect benthic communities bycatch and extraction of living resources; potentially leading to overexploitation of important species sea level rise; changes in sea temperature; changes in oceanography and ocean acidification as a result of climate change invasive species.
Marine bioregional plan for the South west Marine Region Actions that irrespective of where they occur; have a real chance or possibility of resulting in modification; destruction; fragmentation; isolation or disturbance of an important or substantial area of habitat such that an adverse impact on marine ecosystem functioning or integrity of the west coast inshore lagoons results nutrient pollutants; persistent organic chemicals; heavy metals or other potentially harmful chemicals accumulating in the west coast inshore lagoons have a high risk of a significant impact on the Commonwealth marine environment Actions that introduce a new source from which a severe oil spill or other chemical pollution has a reasonable potential of arising (e.g. port developments that increase shipping and drilling) in the west coast inshore lagoon habitats have a risk of significant impact on the Commonwealth marine environment of the South west Marine Region.
Potential pressures on ecosystem functioning and integrity of this key ecological feature include changes to water quality due to chemical and nutrient pollution or changes in turbidity physical habitat modification extraction of living resources noise pollution (considered in Schedule 2.5) oil pollution sea level rise; changes in sea temperature; changes in oceanography and ocean acidification as a result of climate change invasive species.
Climate change; through shifts in the strength of the Leeuwin Current; has the potential to alter the ecological values of this feature. 148
Marine bioregional plan for the South west Marine Region.
Potential pressures on ecosystem functioning and integrity of this key ecological feature include bycatch changes in sea temperature; changes in oceanography and ocean acidification as a result of climate change oil spills; as a number of species aggregate in the area (although the likelihood of oil spills is currently low; there is potential for the likelihood to increase as shipping traffic particularly of large vessels increases around the south west corner).
Potential pressures include changes in sea temperature; change in oceanography and ocean acidification as a result of climate change.
Existing pressures on the integrity of habitats in this key ecological feature include bycatch changes in sea temperature; change in oceanography and ocean acidification as a result of climate change noise generating activities which might affect large whales that use these habitats (these are considered in Schedule 2.5).
Potential pressures on the biodiversity values of this key ecological feature include extraction of living resources and bycatch severe oil spills; nutrient pollution and chemical pollution sea level rise; changes in sea temperature; change in oceanography and ocean acidification as a result of climate change invasive species.
Potential pressures on the integrity of habitats of this key ecological feature include physical habitat modification from activities such as bottom trawling (although this activity is limited by the morphology of the sea bed). sea level rise; changes in sea temperature; change in oceanography and ocean acidification as a result of climate change extraction of living resources.
Potential pressures on the ecological functioning and integrity of this key ecological feature include oil spills affecting aggregations of species at upwellings extraction of living resources and bycatch changes in sea temperature; change in oceanography and ocean acidification as a result of climate change noise pollution for marine megafauna (considered in Schedule 2.5).
They therefore provide an important food source for mesozooplankton in otherwise oligotrophic waters.
Marine bioregional plan for the South west Marine Region Potential pressures include changes in sea temperature; change in oceanography and ocean acidification as a result of climate change.
Potential pressures on this species include oil pollution; marine debris and pressures associated with climate change.
Pressures of concern include changes in sea temperature and oceanography (such as shifts in the strength of the Leeuwin Current) as a result of climate change.
Pressures of potential concern include sea level rise; ocean acidification (due to climate change); changes in turbidity; physical habitat modification; extraction of living resources and oil pollution.
Pressures of potential concern on this feature include changes in sea temperature and oceanography and ocean acidification as a result of climate change and physical habitat modification (such as caused by damage to benthic communities from bottom trawling).
Marine bioregional plan for the South west Marine Region|Pressures of concern for this key ecological feature include changes in sea temperature and oceanography as a result of climate change.|Pressure of potential concern include ocean acidification (due to climate change) disease (the introduction of a herpes virus in the late 1990s resulted in high levels of mortality among pilchards off Albany).
Climate change related pressures are of potential concern to all four species.
Marine bioregional plan for the South west Marine Region People planning to undertake actions in biologically important areas for humpback; sperm; southern right and blue whales should carefully consider the potential for their action to have a significant impact on the species.
Climate change is of concern; or of potential concern to all six species of bird.
The main drivers and sources of pressure on conservation values in the South west Marine Region are climate change and associated large scale effects; including shifts in major currents; rising sea levels; ocean acidification; and changes in the variability and extremes of climatic features (e.g. sea temperature; winds; and storm frequency and intensity) harvesting of living resources fast urban and industrial development in areas adjacent to the region increases in shipping and port activities growth in marine industries and infrastructure defence training activities within the Western Australian training exercise area off Perth emergence of offshore renewable energy industries.
For some of these species; changes in distribution and or prey availability have been recorded from the region and have been attributed to climate change.
The significance of the region to their ecology and their potential vulnerability to climate change and its effects make the species’ a regional priority for conservation.|Any wholesale shift in the productivity and trophic regimes of the region’s ecosystem in response to climate change has the potential to significantly affect large top predators; such as sharks.
As for other shark species; any wholesale shift in the productivity and trophic regimes of the region’s ecosystem in response to climate change has the potential to significantly affect large top predators.
Table 4.2 Pressures of regional priority for the South west Marine Region Pressure Rationale Strategies and actions identified to address the priority (see Section 4.2) Climate change 44
Marine bioregional plan for the South west Marine Region Strategy A; Action Strategy B; Action Strategy C; Action Climate change related pressures including changes in sea temperature; ocean acidification; sea level rise are predicted to increase in the South west Marine Region; with the potential to impact most conservation values to varying extents.|Loss of climatic habitat caused by anthropogenic emissions of greenhouse gases is listed as a key threatening process under the EPBC Act.
Climate change has been identified as a priority because of the extent of predicted impacts on conservation values in the region; particularly the cumulative nature of these impacts.
Support research to improve information on the impacts of climate change on protected species and key ecological features in particular; their vulnerability and adaptive capacity to predicted changes (regional priorities 1 19 medium to long term).
Longer term predictions estimate increases of 0.5 m to 1 m by 2100; relative to 2000 levels (Climate Commission 2011).
All key ecological features considered important for the region’s primary productivity and biological production are at risk from climate change.
Longer term predictions estimate increases of 0.5 m to 1 m by 2100; relative to 2000 levels (Climate Commission 2011).
Western rock lobster Naturaliste Plateau Changes in sea temperature (climate change) Diamantina Fracture Zone Sea temperatures have warmed by 0.7 C between 1910 1929 and 1989 2008; and current projections estimate ocean temperatures will be 1 C warmer by (Lough 2009).
Geographe Bay Loss and disturbance of mangrove habitat in the Houtman Abrolhos Islands due to Ancient coastline climatic changes and or further future development would have significant impacts (GAB) on the year round resident seabird populations of Australian lesser noddy.
Gunther’s pipehorse has a diet of small crustaceans and larval fish the species might be affected by climate related changes to the region’s productivity and trophic processes.
The impact of climate change on the winter southern bluefin tuna feeding grounds in the southern ocean may be significant (Sarmiento et al. 2004 cited in Hobday et al. 2008).
Driven by increasing levels of atmospheric CO; and subsequent chemical changes in the ocean; acidification is already underway and detectible.
Marine debris and sea level rise; changes in sea temperature and oceanography and ocean acidification are also of potential concern to the school shark.
Pressures of potential concern on this feature include changes in sea temperature and oceanography and ocean acidification noise pollution physical habitat modification extraction of living resources and bycatch noise generating activities; such as seismic surveying; might have an adverse effect on demersal fish species (for example; experimental studies on pink snapper in Western Australia have demonstrated physiological damage after exposure to seismic surveying McCauley et al. 2003).
Table S1.2 Summary of pressures on key ecological features and historic shipwrecks of the South west Marine Region Pressure Key ecological feature Sea level rise Changes in sea temperature Change in oceanography Ocean acidification Chemical pollution contaminants Nutrient pollution Changes in turbidity Marine debris Noise pollution 1.
Table S1.2 continued Summary of pressures on key ecological features and historic shipwrecks of the South west Marine Region Pressure Key ecological feature Sea level rise Changes in sea temperature Change in oceanography Ocean acidification Chemical pollution I contaminants Nutrient pollution Changes in turbidity Marine debris Noise pollution Light pollution 12.
Table S1.3 continued Summary of pressures on selected protected species in the South west Marine Region Pressure Species group Protected species Sea level rise Changes in sea temperature Change in oceanography Ocean acidification Chemical pollution I contaminants Nutrient pollution Changes in turbidity Marine debris Noise pollution Light pollution Seabirds Indian yellow nosed albatross Great winged petrel Soft plumaged petrel White faced storm petrel Flesh footed shearwater Little shearwater Short tailed shearwater Wedge tailed shearwater Bridled tern Caspian tern Fairy tern Roseate tern Sooty tern Australian lesser noddy Common (brown) noddy Pacific gull Little penguin Black faced cormorant Legend of concern of potential concern of less or no concern Some pressures considered in this analysis are made up of more than one category but are presented in this summary table under one heading.
Table S1.3 continued Summary of pressures on selected protected species in the South west Marine Region Pressure Species group Protected species Sea level rise Changes in sea temperature Change in oceanography Ocean acidification Chemical pollution I contaminants Nutrient pollution Changes in turbidity Marine debris Noise pollution Light pollution Sharks Grey nurse shark Longfin mako shark Shortfin mako shark Porbeagle shark School shark White shark Legend of concern of potential concern of less or no concern Some pressures considered in this analysis are made up of more than one category but are presented in this summary table under one heading.
Research on the impact of ocean acidification on Antarctic krill has found that increased levels of CO; kill their embryos (Kawaguchi et al. 2010).
Consequently; acidification impacts have the potential to affect species further up the food chain.
The potential effects of increased acidity on the region’s biodiversity also include changes to growth and population dynamics of some shell forming organisms; impacts on the reproductive and metabolic functions of a number of fish and invertebrate species; and sensitivity of some early life stages to acidification (Orr et al. 2009).
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Australian Government Species group report card - bonyfishes (South West Marine Region)
Given predicted impacts resulting from climate change; syngnathids are susceptible as they have low mobility; which may limit their ability to find and adapt to suitable new habitat.
Gunther’s pipehorse is likely to have a diet of small crustaceans; and possibly larval fishes the species might be affected by climate related changes to the region’s productivity and trophic processes; but its distribution and its use of the region’s habitats are poorly known.
The impact of climate change on the winter southern bluefin tuna feeding grounds in the Southern Ocean may be significant (Sarmiento et al. 2004 cited in Hobday et al. 2008).
Driven by increasing levels of atmospheric carbon dioxide and subsequent chemical changes in the ocean; acidification is already underway and detectible.
While evidence is absent; increasing acidification of the oceans is likely to be less of an issue for temperate fish species; and a direct impact only during the larval life stages (Hobday et al. 2009).
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Australian Government Species group report card - cetaceans (South West Marine Region)
Ocean acidification climate change Driven by increasing levels of atmospheric carbon dioxide and subsequent chemical changes in the ocean; acidification is already underway and detectible.
There are no observed impacts of climate change on zooplankton in Australian waters.
Recent research on the effects of ocean acidification on Antarctic krill has found that increased levels of carbon dioxide kill their embryos (Kawaguchi et al. 2010).
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Australian Government Marine environment report card (South West Marine Region)
As such; the Houtman Abrolhos Islands can provide insight into coral responses to climate change; which may be important for managing coral reefs in the face of rising global temperatures (Richardson et al. 2005).
Albany canyon group and adjacent shelf break Sea level rise Climate change Climate change Changes in sea temperature Climate change Change in oceanography Climate change Ocean acidification Chemical pollution I contaminants Agricultural activities Aquaculture operations Onshore and offshore mining operations Renewable energy operations Shipping Urban development (urban and or industrial infrastructure) Vessels (other) Nutrient pollution Agricultural activities Aquaculture operations Urban development Changes in turbidity Climate change (changes in rainfall; storm frequency) Dredging (spoil dumping) Land based activities Onshore and offshore mining operations Marine debris Noise pollution Defence surveillance activities Onshore and offshore construction Onshore and offshore mining operations Renewable energy infrastructure Seismic exploration Shipping Urban development Vessels (other) Light pollution Physical habitat modification Dredging (and or dredge spoil) Fishing gear (active and derelict) Offshore construction and installation of infrastructure Offshore mining operations Onshore construction Telecommunications cables Urban coastal development Legend of concern of potential concern of less or no concern Table 1 continued Outputs of the key ecological feature pressure analysis for the South west Marine Region Note To maintain uniformity among all bioregions; this table has been added subsequently to the review by independent experts.
Small pelagic fish of the south west marine region Sea level rise Climate change Climate change Changes in sea temperature Climate change Change in oceanography Climate change Ocean acidification Chemical pollution I contaminants Agricultural activities Aquaculture operations Onshore and offshore mining operations Renewable energy operations Shipping Urban development (urban and or industrial infrastructure) Vessels (other) Nutrient pollution Agricultural activities Aquaculture operations Urban development Changes in turbidity Climate change (changes in rainfall; storm frequency) Dredging (spoil dumping) Land based activities Onshore and offshore mining operations Marine debris Noise pollution Defence surveillance activities Onshore and offshore construction Onshore and offshore mining operations Renewable energy infrastructure Seismic exploration Shipping Urban development Vessels (other) Light pollution Physical habitat modification Dredging (and or dredge spoil) Fishing gear (active and derelict) Offshore construction and installation of infrastructure Offshore mining operations Onshore construction Telecommunications cables Urban coastal development Legend of concern of potential concern of less or no concern Table 1 continued Outputs of the key ecological feature pressure analysis for the South west Marine Region Note To maintain uniformity among all bioregions; this table has been added subsequently to the review by independent experts.
Small pelagic fish of the south west marine region Human presence at sensitive sites Nuisance species Extraction of living resources Commercial fishing (domestic or non domestic) Commercial fishing prey depletion Bycatch Commercial fishing Oil pollution Oil rigs Onshore and offshore mining operations Shipping Vessels (other) Collisions with vessels Collision entanglement with infrastructure Disease Aquaculture operations Fishing Shipping Tourism Invasive species Aquaculture operations Fishing vessels IUU fishing and illegal immigration vessels Land based activities Shipping Tourism Vessels (other) Legend of concern of potential concern of less or no concern Sea level rise climate change Global sea levels have risen by 20 cm between 1870 and 2004 and predictions estimate a further rise of 5 15 cm by 2030; relative to 1990 levels (Church et al. 2009).
Longer term predictions estimate increases of 0.5 to 1 m by 2100; relative to 2000 levels (Climate Commission 2011).
Changes in sea temperature; ocean circulation and currents climate change Changes in sea temperature; ocean circulation and currents are either of potential concern or of concern with respect to all key ecological features.
The structure of ecological communities of the continental shelf might be affected by climate related changes kelps in the central and southern Houtman Abrolhos Islands are at the northern limit of their distribution and an increase in sea surface temperature could have a direct negative effect on their distribution in the region.
Seagrass habitat is particularly susceptible to climate change pressures; and projected altered oceanic circulation due to climate change is likely to affect seagrass community species composition.
Key ecological features that are driven by oceanographic processes (such as meso scale eddies) are particularly vulnerable to changes in physical parameters (e.g. sea surface temperature; intensity and direction of currents) arising from climate change.
Upwelling off Kangaroo Island is enhanced by El Niño events; in part due to the increased frequency of upwelling favourable winds (Middleton et al. 2007); which is expected to further increase as a result of climate change (Hobday et al. 2006).
Climate change may also cause substantially increased summer upwelling (and decreased downwelling in winter) in the Eyre and Bonney coastal systems if it leads to increased El Nino conditions in these systems (Hayes et al. 2008).
Ocean acidification climate change Ocean acidification is of potential concern for all key ecological features in the region.
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Australian Government Species group report card - Pinnipeds (SouthWest Marine Region)
Species Pressure Source Australian sea lion New Zealand fur seal Light pollution Physical habitat modification Human presence at sensitive sites Recreational and charter fishing (burleying) Research Tourism Nuisance species Aquaculture operations Extraction of living resources Commercial fishing prey depletion Bycatch Commercial fishing Oil pollution Oil rigs Onshore and offshore mining operations Shipping Vessels (other) Collision with vessels Collision entanglement with infrastructure Aquaculture infrastructure Oil and gas infrastructure Renewable energy infrastructure Disease Invasive species Legend of concern of potential concern of less or no concern Sea level rise climate change Global sea levels have risen by 20 cm between 1870 and 2004 and predictions estimate a further rise of 5 15 cm by 2030; relative to 1990 levels (Church et al. 2009).
Longer term predictions estimate increases of 0.5 to 1 m by 2100; relative to 2000 levels (Climate Commission 2011).
With its similar life history characteristics; New Zealand fur seals are likely to be affected by climate change in a similar way to Australian sea lions.|Changes in sea temperature climate change Sea temperatures have warmed by 0.7 C between 1910 1929 and 1989 2008; and current projections estimate ocean temperatures will be 1 C warmer by 2030 (Lough 2009).
Driven by increasing levels of atmospheric carbon dioxide and subsequent chemical changes in the ocean; acidification is already underway and detectible.
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Australian Government Species group report card - reptiles (South West Marine Region)
Species Pressure Source Green turtle Leatherback Loggerhead turtle turtle Sea level rise Climate change Changes in sea temperature Climate change Changes in oceanography Climate change Ocean acidification Climate change Chemical pollution contaminants Nutrient pollution Changes in turbidity Marine debris Aquaculture infrastructure Fishing boats Land based activities Oil rigs Renewable energy infrastructure Shipping Urban development Vessels (other) Aquaculture infrastructure Noise pollution Defence surveillance activities Onshore and offshore construction Onshore and offshore mining operations Renewable energy infrastructure Seismic exploration Shipping Urban development Vessels (other) Light pollution Physical habitat modification Human presence at sensitive sites Nuisance species Extraction of living resources Bycatch Commercial fishing Oil pollution Collision with vessels Fishing Shipping Tourism Collision entanglement with infrastructure Disease Invasive species Legend of concern of potential concern of less or no concern Changes in sea temperature climate change Increases in sea temperatures are of potential concern to marine turtles through changes to their distribution and reproductive ability.
Impacts on turtles from rising sea temperatures in the region may include changes to the distribution of green; leatherback and loggerhead turtles increased water temperatures may extent the foraging range they are physiologically capable of withstanding an increase in leatherback breeding capacity associated with an increase in available foraging species (e.g. jellyfish) reduction is expected in loggerhead turtle breeding capacity associated with a decrease in ocean productivity and prey abundance (e.g. in benthic invertebrates) due to warming in foraging areas (Chaloupka et al. 2008) reduction in green turtle breeding capacity associated with a decrease in foraging habitat seagrasses are highly vulnerable to a changing climate (Connolly 2009) for example; almost 13 000 hectares of seagrass was killed by heat stress in a single incident in the Spencer Gulf; South Australia; in 1993 during an El Niño event (Seddon et al. 2000; in Connolly 2009).
The thermal requirements of marine reptiles are expected to result in changes in their distributions as climate change progresses.
The Leeuwin Current is known to be weaker during El Niño and is therefore likely to diminish if climate change results in extended El Nino years (Hayes et al. 2008).
Ocean acidification climate change Ocean acidification is of potential concern to marine turtles.
Interactions with fisheries may increase as a result of possible changes to the turtles’ distributions as climate change progresses.
Driven by increasing levels of atmospheric carbon dioxide and subsequent chemical changes in the ocean; acidification is already underway and detectible.
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Australian Government Species group report card - seabirds (South West Marine Region)
Species Pressure Source Sooty tern Australian lesser noddy Common (brown) noddy Pacific gull Little penguin Black faced cormorant Light pollution Fishing boats Land based activities Oil and gas infrastructure Onshore and offshore activities Onshore and offshore mining operations Renewable energy infrastructure Vessels (other) Physical habitat modification Dredging (and or dredge spoil) Onshore construction Urban coastal development Human presence at sensitive sites Nuisance species Aquaculture operations Extraction of living resources Commercial fishing prey depletion Bycatch Oil pollution Oil rigs Onshore and offshore mining operations Shipping Vessels (other) Collision with vessels Fishing Tourism Collision entanglement with infrastructure Disease Aquaculture operations Fishing Shipping Tourism Invasive species Legend of concern of potential concern of less or no concern Sea level rise climate change Global sea levels have risen by 20 cm between 1870 and 2004 and predictions estimate a further rise of 5 15 cm by 2030; relative to 1990 levels (Church et al. 2009).
Changes in sea temperature and changes in oceanography climate change Sea temperatures have warmed by 0.7 C between 1910 1929 and 1989 2008; and current projections estimate ocean temperatures will be 1 C warmer by 2030 (Lough 2009).
Ocean acidication climate change Ocean acidity is of potential concern to all seabird species in the South west Marine Region.
Driven by increasing levels of atmospheric carbon dioxide and subsequent chemical changes in the ocean; acidification is already underway and detectible.
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Australian Government Species group report card - sharks (South West Marine Region)
Longer term predictions estimate increases of 0.5 to 1 m by 2100; relative to 2000 levels (Climate Commission 2011).
Change in oceanography climate change Changes in the strength of the Leeuwin Current are of potential concern to white sharks; grey nurse sharks; porbeagle sharks and school sharks through changes in productivity; influencing the distribution and abundance of sharks.
Driven by increasing levels of atmospheric carbon dioxide and subsequent chemical changes in the ocean; acidification is already underway and detectible.