The slow and gentle dugong has developed an interesting strategy to avoid its nemesis, tiger sharks.
Australia’s shark bay is home to over ten-thousand dugongs.
It seems like a perfect spot for these air-breathing herbivores. The water is shallow and peppered with beds of sea grass, the dugongs main source of food.
Biologist Aaron Wirsing has come here from Canada to study the dugong.
Aaron Wirsing: “We know almost nothing about its habitat use patterns, its feeding habits, and the way it gets along with some of its major predators like tiger sharks.”
The tiger shark, a beautiful, agile, and powerful hunter is the one thing that keeps shark bay from being a paradise for the slow moving dugongs.
Named for their stripes, tiger sharks are massive warm-water predators capable of growing over 14ft long, and reaching weights of 2,000 pounds.
Seems like a bit of a mismatch for the smaller dugongs, which are more closely related to the elephant than to other seafaring mammals like seals and walruses.
Aaron Wirsing: “And there’s a very interesting race going on right here in shark bay between dugongs and tiger sharks.”
To get a closer look at that race from the perspective of the dugongs, our team deploys some Crittercams.
The team is eager to learn what they can about how these clumsy looking vegetarians manage to evade the tiger sharks.
There are a few surprises in store. First of all the dugongs are going much deeper than Aaron thought.
But there’s not nearly as much food down here as there is in the shallower waters. Still, the Cittercam team believes that feeding at greater depth may be how the dugongs manage to evade the sharks.
Shallow water means tiger sharks. So dugongs do a lot of their foraging in deep water where the tiger sharks don’t hunt.
Another of nature’s mysteries solved, thanks to a dedicated team of scientists and Crittercam.