Seismic Testing on Sharks

It is critically important that these sharks are protected. This is particularly true for the School Shark/Eastern School Shark/Snapper Shark/Tope/Soupfin Shark.


For over 420 million years, sharks and rays have roamed our oceans, maintaining balance in ever-changing marine ecosystems. Australia is home to 322 species of sharks and rays, with 51% of these unique to our waters.


Predators are a vital component of ecosystem health. Large sharks are apex predators and are a significant part of marine ecosystems, but they are also slower growing than other species, later to breed and have relatively few offspring. 


Fishing and other human activities have dramatically reduced shark numbers all over the world, particularly in recent decades, and they are very sensitive to any disturbance. Because they breed relatively late in life and have fewer offspring than many large fish, it would take a long time for shark numbers to recover. 

 

In 2014, nearly a quarter of shark species were listed as threatened or endangered by the International Union for the Conservation of Nature (IUCN). By 2021 this number had grown to more than one-third of all sharks now facing extinction. Many more have not been sufficiently studied to conclude their conservation status. 


Vessel strikes can be lethal to sharks, but other collisions can result in injuries to the back and dorsal fin of sharks leading to blood loss, possible infection and reduced swimming ability. Sharks are highly mobile and could be in the area subjected to shipping associated with drilling at any time. The report admits that there is a lack of data about the reporting of collisions to marine life.


Some sharks are voracious eaters that gobble down whatever they find, including things that aren’t very digestible, like bird feathers, turtle shells, or other bones. If a shark finds itself in a high-stress situation which could result from drilling or seismic testing its instinct reaction is to get rid of that foreign, hard-to-digest food right away to make it easier to escape on an empty stomach. A stressed pregnant shark might abort its foetus in similar conditions.


Written by Tim Hawthorne

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