Our Coastal & Marine Vulnerabilities

The following key vulnerabilities to the coastal and marine systems of the NAR have been identified:

Coastal development

Development including urban areas, infrastructure and resource extraction results in the direct loss of coastal habitat. Indirect impacts may include soil salinity, contamination or erosion problems. Coastal infrastructure related to ports and marinas may also impact natural sand movements, resulting in changes to erosion and accretion patterns. Consideration must be given to social amenity and public access, as well as the management of coastal process risks (hazards) and the adequacy of coastal foreshore reserves. Such developments have also led to loss of some seagrass in the area.

Vegetation loss on local sand dunes

Vegetation loss has not only occurred on dunes, but also on some areas of limestone and sandstone. Evidence of other contributors to degradation of vegetation include: uncontrolled traffic, illegal waste disposal, fire (Lancelin, Cervantes), illegal residency, resource exploration south of Dongara, and firewood poaching.

Vegetation loss in riparian areas

Estuaries associated with the Greenough, Irwin, Chapman Rivers have lost riparian vegetation and ecological function as a consequence of recreational, agricultural and urban use.

Increase in nutrients

Increased nutrients, toxicants, sediment and litter all impact benthic primary producer habitats and invertebrate and fish communities. Increased nutrient loading may contribute to the creation of favourable conditions for microalgal blooms, for example Nodularia, blocking sunlight to benthic seagrasses and macroalgae and creating anoxic conditions.

Recreation activities and tourism

Activities such as boating, diving, island visitation and reef walking have the potential to result in significant coastal impacts. Access to vulnerable areas including offshore islands by boat and off road vehicles can impact on coastal ecosystems, social amenity and safety through the destruction of habitat and landform from mooring and anchoring scouring habitat, the introduction of pests and weeds, collection of firewood and dumping of litter and rubbish.

Land ownership and public access

In some areas the only coastal access is through private property, creating conflicts for land owners, the public and coastal managers. The adequacy of foreshore reserves and public access points may require a review in some locations, and particularly as local populations grow.

Inappropriate access of coastal areas

Areas of high activity along the NAR coast have been heavily affected by increased use of 4WD vehicles on the foredunes and beaches. The most severely disturbed areas are adjacent to towns such as Geraldton, Dongara, Green Head, Jurien, Cervantes, Lancelin and Ledge Point, but accessing of more remote surfing, fishing and camping spots along the coast has caused significant degradation.

Commercial and recreational fishing

Where inappropriately managed, commercial and recreational fishing has the potential to deplete fish stocks and impact on marine environments and other marine species. Changes in climatic conditions are also likely to have a significant impact on current fishing practices.

Decreased marine and coastal water quality

Water quality in marine and coastal waters can be impacted in many ways and from various sources: increased turbidity from dredging for shipping channels and port development, oil and gas exploration, and seasonal discharges from rivers; eutrophication resulting from sewage, septic tanks, agricultural catchments, aquaculture feeding, rock lobster processing outfalls, and urban stormwater runoff; contaminant inputs from spills, hull antifouling of boats, pesticides and herbicides from agricultural catchments, oil spills from shipping/petroleum production, and metals from historic mining activities; and litter and waste from commercial and recreational boating and urban stormwater runoff.

Aquatic biosecurity

Aquatic pests and diseases are a significant threat to Western Australia’s oceans and rivers. Aquatic pests can be transported by ocean-going vessels, and by escaping or being released into coastal waters and rivers. Pests and diseases can devastate aquatic ecosystems damaging economies, environments and lifestyles.

Shoreline retreat

Some areas of the coast, such as Seabird and Horrocks, are experiencing shoreline retreat due to natural causes. Other foreshore areas, such as the northern beaches of Geraldton, are experiencing significant change in the shoreline that is at least partially attributable to construction of coastal infrastructure (Worley Parsons, 2010). Changes to climate and sea level are predicted to accelerate coastal recession throughout the region (NACC, 2005).

Climate change

Changing climatic conditions create coastal management issues through impact on coastal ecosystems and coastal communities, and requires integrated planning responses. Impacts include sea level rise, storm surge, coastal erosion and recession, coastal inundation, changing rainfall patterns, increasing ocean surface temperatures, changing current patterns and wave heights, ocean acidification, and a change in the distribution and functioning of marine systems.

Resource sharing

The population along the Western Australian coast continues to grow and therefore the increase usage of the coastline by recreational angulars is increasing. This sometimes leads to conflicts between commercial and recreational fishers.

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