The Affect of Seismic Surveying on Bluefin Tuna Migration in the Bight off Australia

Following on from my previous blog: Seismic Effects on the South African and Namibian Tuna 2012/2013 Season, as mentioned I would discuss the effects the seismic testing has had on the Australian’s Southern Bluefin Tuna migration and subsequent poor catches.

The Australian Southern Bluefin Tuna Industry (ASBTIA) is strongly opposing and contesting the seismic surveying being conducted in the Great Australian Bight in first half of 2013 by Bight Petroleum (a Canadian Company). The tuna industry is arguing that the surveys are being conducted near the eastern part of the Bight where the bluefin tuna migrate through.  The association has gone on to say that due to the high level of concern they were considering launching action under the Common Wealth Environment Act to put a stop to the surveys. Some 3000 locals are employed in their tuna industry both directly and indirectly. This would be ideal for us in South Africa and Namibia if we had such acts in our constitution…but alas we have no such Act but since both governments are prioritizing job creation for the unemployed I feel that this should be a priority considering the number of people employed within the fishing sector. (One would think?) 

Now back on topic, the bluefin tuna migrate normally through the Bight for approximately five months out of the year and a temporary solution would therefore be to conduct the surveys outside of these months. During November 2011 to May 2012 whilst BP was conducting their seismic surveying in the Western Bight, the migration paths of the tuna completely changed. The ASBTIA went on to say that long term documented data by CSIRO from the past 30 years indicated that the tuna migrate directly thought the surveying area each year. The Australians usually catch their tuna west of Port Lincoln and the 2012 season catch data shows the exact opposite and in fact was caught east of the port. The last time bluefin were caught near Kangaroo Island was way back in 1980 according to ASBTIA. The only change to the Australian tuna season is that of the seismic activity and this variable is now speculated to have been the real factor behind this. 

The tuna industry has since done research to try and explain the reasoning behind the change. The Australians have gone on to spend approximately AUS$20mill (A portion contributed by BP) to fund the study of the ecosystem as a whole. I can never imagine either of the Southern African countries collectively budgeting, even a small portion of this amount into the same research here. (Long may I live to eat my own words)

On the political front there are two politicians opposing the seismic testing namely Senators Penny Wright and Rachel Siewert who argue that the seismic testing around Kangaroo Island has unacceptable environmental risks no matter the time of year. They have gone on to say that the region is home to more than 20 species of whales and dolphins and the Southern Bluefin Tuna are known to migrate here as well and marine reserves should not be compromised by industries which damage biodiversity and sustainable fishing. 

Just like back home, an immediate solution would be for the seismic surveying to be conducted outside of the tuna migrating and catching season. Until we have conclusive data documenting that seismic activity does in fact impact the migration of tuna, this will remain a “David VS Goliath” scenario.

Ref: Port Lincoln Times