Threatened species of the north west

 

Australia’s North West is home to some of our most iconic marine animals, such as whales, dugongs, sea turtles and sharks. Unfortunately, many of these are listed threatened species.

To manage potential threats from industrial activities on these animals, we need to understand where the populations are, where they move and the key areas they use to breed and feed. We can then better understand where they overlap with human activities and manage threats accordingly. This was the subject of Theme 3 of the North-west Shoals to Shore Research Program (NWSSRP).

Whales

Pygmy blue whales, a subspecies of the blue whale, are listed nationally as endangered. Before the NWSSRP information on their distribution and important areas was limited, especially in the north-west.

Researchers used three innovative methods to understand pygmy blue whale movement and distribution:

• attaching satellite tracking devices to individuals,
• recording their vocalisations using underwater microphones on the seafloor and on ocean gliders and,
• distribution modelling.

From analyses of the data collected, we mapped their distribution and important areas of use and used it to locate high-risk areas for pygmy blue whales and a range of other species on the North West Shelf.

For example, ship strike is a threat for these large whales, especially where there are higher numbers of vessels in the same vicinity. By using information on vessel activity with information on whale movement and distribution and identifying the overlap between the animals and vessels we have identified 'hotspots' of exposure to this and other threats. View the results by clicking here. 

AIMS research on pygmy blue whale movement is ongoing, and in particular on their diving and feeding behaviour. Learn more about the current research by clicking here.

Turtles

Green turtles and hawksbill turtles face a number of threats, including getting tangled in fishing gear, habitat loss and light pollution, e.g. turtle hatchlings being confused by light. 

In order to protect turtles we need to understand where these wide-ranging species roam and the areas they use the most. To do this AIMS researchers tracked their movements by attaching satellite tags to individual turtles and compiled satellite tracking data from previous studies. An analysis of the combined tracks identified the areas they used during the breeding season, their migratory pathways and the areas they feed. As with the blue whales, these important areas were compared to areas where threats occur, from human activities, such as shipping, oil and gas production, fishing and coastal development. The research highlighted where overlap occurred and where management might be needed to protect turtles and a range of other species from the threats that results from these activities. View the results by clicking here.  

AIMS research on marine turtles is ongoing. Learn more about the current research by clicking here.