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CSULB Shark Lab – Leopard Shark Tagging in Catalina Island

What we’re doing today is trying to
catch leopard sharks in Big Fisherman’s Cove at Catalina Island. so the goal is to get one of our smart tags on the sharks. Now the smart tags enable us to measure all the shark’s movements, the depth, the water temperature that is moving through. The other goal is to put a temperature
transmitter down the sharks into its stomach. And that will tell us its body temperature. So we actually caught a leopard shark this morning and I put a little backpack on it. So the backpack has an accelerometer, so it’s basically a remote so I can sense the movement of the shark, it has an acoustic tag so I can track it, and then it has a VHF and a video camera, so I can see what the shark sees. So, we’re using an autonomous underwater vehicle that’s programmed to follow the shark but not chase the shark. Now the great thing about the robot is it knows exactly where the shark is in 3D space and time. So by recording exactly where the shark is, we’re able to understand why they’re doing what
they’re doing. We have context to the behavior. So the
great thing is in addition to the robot, we also have an array of receivers on
the sea floor that’s also tracking the shark as it moves throughout this area. So, basically in the acoustic receiver, I had a decibel, a signal strength. And that’s
a proxy for how far away the shark is. And when I turn this angle of the
hydrophone it actually changes the angle I’m listening at, so by understanding
where it’s louder, I can figure out what direction the shark is, and I can drive
closer to it, and the signal strength gets louder and louder, and then when it
gets to a certain threshold, I’m basically on top of the shark. If we can understand how sharks are behaving relative to ocean temperatures, then we can make predictions on where sharks may be in the future, or where they more importantly may not be. If we know that, then we can better protect areas from
maybe fishing areas where they may aggregate during certain times of year
because conditions are optimal for sharks. In addition to temperature variability, we can figure out tons of questions about how sharks make decisions of the entire world surrounding them. So we have the video cameras, we can figure out what the shark sees, how it interacts with the environment around it, how it interact with other sharks even, you can sort of figure out how these animals make decisions on where to move how to behave and what to do.

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