Whats the Problem?
Gas, Oil and Australia
Australia has a long history with oil and gas production, the industry has been responsible for building a large part of Australia’s economy. However, in recent years concerns from other stakeholders have questioned the social licence of the industry.
An example of this can be seen when Norwegian company Equinor pulled out of their plans to drill the Great Australian Bight (GAB) due to pressure from the public.
In addition, stakeholders from other industries such as fisheries have recently raised concerns over direct impacts from oil and gas exploration. This has resulted in a senate enquiry into to impacts of seismic testing on fisheries and the marine environment.
Furthermore, Australia become art to the Paris Agreement in 2016, committing to dramatically decrease Co2 Levels by 2030 due to dangers of climate change. There is growing concern that Australia is not doing enough to meet these targets (climate analytics) and a gas-led recovery continues to support a fossil fuel industry, opposed to a renewable one.
Seismic Testing
Seismic testing is the first step in oil and gas exploration. Before resources can be extracted seismic surveys must be carried out to find the resource reservoir. In a 3D survey a vessel tows a sound source, usually airguns. As well as cables with sound receiving devices. This sends sound waves down through the seabed, penetrating kilometres into the earth. The receivers record how long it takes for the sound to bounce back up. Once the data is collected scientists with the help of computer technology can create a 3D map of the underground structures. This allows them to find oil and gas reservoirs.
The noise pollution from seismic surveys can have a negative impact on our marine creatures. Whilst the impacts on marine mammals have been studied for some time, the impacts on crustaceans are just starting to be explored.
Marine mammals rely on sound a lot! They use it to navigate, find food, interact and find mates. Seismic blasts are some of the loudest man made sounds in the world. These can cause the whale to become lost, stop feeding and stop communicating with one another.
New research has found negative impacts on crustaceans too. In southern rock lobster sensory organs can be damaged and their ability to keep themselves upright is compromised.
in Addition it has been found that seismic blasts can cause mortality in scallops and zooplankton.
Zooplankton and North West Tasmania.
The Australian continent (including Tasmania) has two major boundary currents. The Eastern Australian Current (EAC) which runs poleward from northern Queensland. And the Leeuwin Current (LC) which flows from Western Australia, GAB and down the west coast of Tasmania, where it is known as the Zeehan Current.
Both currents bring warm waters to Tasmania. The EAC is dominant in the summer months and the LC dominant in the winter months (Buchanan et al. 2013). When the LC is dominant it wraps around the southern tip of Tasmania. Whilst the behaviour of the EAC can vary from year to year, the LC is generally consistent in it patterns (Ridgeway 2007). Despite the LC’s consistent flow of warm water from the GAB the coastal dependency of this current is yet to be explored in any detail (Buchanan et al. 2013). Although studies have confirmed that the LC is of critical importance to a range of fisheries on mainland Australia, like the western rock lobster industry (Waite et al. 2007).
This is because both the LC and EAC are primary drivers for biological diversity on the Australian continental shelf (Buchanan et al. 2013). The currents deliver nutrients, zooplankton and phytoplankton which fuel primary productivity for all other species (Parks and Wildlife Australia 2007). Therefore, any changes to these currents can result in biodiversity impacts for coastal marine life (Buchannan et al. 2013). Further changes are seen in primary productivity throughout la Nina and el Nino events, with the current strengthening to create more upwelling during a la Nina. Changes on Tasmania’s east coast due to a strengthening EAC have been well documented. However, the influence of the LC on coastal communities in Tasmania is yet to be studied in any detail (Buchanan et al. 2013).
Zooplankton, which are carried in by ocean currents such as the LC and EAC, are pivotal for a healthy ocean. Any impact to these communities can have huge impacts on ecosystems (McCauley et al. 2017). A study by McCauley et al. published the first study of the effects of seismic testing on zooplankton in 2017. The Study concluded that using airguns for seismic testing resulted in a two to threefold increase in mortality of zooplankton. A range of 1.2km was sampled and with the mortality rate staying the same for the whole range. McCauley et al. also comments that zooplankton communities are of high importance for Laval stages of important fisheries (McCauley et al. 2017).
The area currently under exploration intercepts with the LC as well as the Zeehan Australian Marine Park (AMP). The Zeehan AMP is home to a diverse range of marine life. This is partly due to the Western Tasmanian canyons (WTC) within the MPA (ConocoPhillips 2020). These canyons are responsible for delivering an upwelling of nutrients to the area. In addition, they assist with the dispersion of larva and juvenile organisms. The enhanced productivity resulting from these canyons supports fish nurseries, seabirds, white shark as well as blue and humpback whales (ConocoPhillips 2020).
Senate Inquiry into Impacts of Seismic Testing
In September 2019 a parliamentary inquiry into the impacts of seismic testing on Australian Fisheries and the Marine Environment was Launched. 85 party’s contributed submissions to the inquiry. Lets go over some of the submissions:
CSIRO
The CSIRO’s submission provided a comprehensive overview of the science that has been completed on this issue. Highlighting there are substantial knowledge gaps around the impact of anthropogenic noise such as seismic airguns on marine life. Suggesting, whilst there has been considerable research conducted on the impacts to marine mammals, little is known about impacts to fish and invertebrates (CSRIO 2019).
The submission also addresses the difficulty in carrying out experimental studies. Many of the science completed to date has been based on observation studies within controlled environment’s and have so far had varying results. Due to the way sound travels, it can have varying effects depending on its location. This makes it very hard to compare results from observational studies or controlled environments to real world situations (CSIRO 2019). Furthermore, concern is displayed that a balance of conserving the health and natural capital of our oceans and economic benefits of resource extraction have not been achieved. Potentially resulting in a lack of confidence within management and regulation of the industry (CSIRO 2019).
IMAS
The Institute of Marine and Antarctic Study’s (IMAS) also included a comprehensive overview of completed science. Although this submission focused on commercially important species such as Southern Rock Lobster (SRL) and scallops as well as plankton.
In 2010 a seismic survey was carried out in Bass Straight, soon after this scallop fishermen in the area reported large losses in catches. At the end of the 2011 season the scallop industry blamed a loss of 24,000 tones and $70m directly on the impact, from the seismic survey. This highlighted a requirement for more research to be developed on the impacts from seismic surveys on invertebrate species, particularly those of commercial importance (IMAS 2019).
This prompted a research project through Fisheries Research and Development Corporation (FRDC) to investigate the impacts of exposure to seismic signals on the commercial scallop and the SRL. In conclusion the research program found that scallops were most effected although effects were not seen immediately. Over a 4-month period the physiology health of the scallops declined with no recovery. Furthermore, higher exposure to air gun noise increased mortality rates significantly (IMAS 2019).
Studies carried out on impacts to SRL concluded no damage to embryos from seismic testing. However, it is important to note these results may differ through different larval stages which were not investigated. For the adult SRL there were no cases of mortality were observed. Although evidence suggested impacts included a reduced ability to digest food, a lower count of blood cells and damage to the mechanosensory organs (IMAS 2019).
Regarding plankton, IMAS supports the research conducted by McCauley et al, 2017, this is addressed within the Primary productivity section of this paper. And acknowledges the need for additional research (IMAS 2019).
The submission acknowledges substantial knowledge gaps around the impacts from seismic surveys on marine life. Whilst the research outlined within the submission provides evidence of harm to marine life from seismic surveys. There are still large amounts of research to be completed to ensure prosperity of the coexistence of Australian fisheries and the oil and gas industry (IMAS 2019).
