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  • I'm out here with my team and we're doing surveys for sharks

  • so we're using drones to fly along the beach to look for sharks that we see

  • close to shore and if we see them from the video we can use that to estimate

  • their size and determine what species most of the sharks you see here are juvenile

  • white sharks and we believe this is a really good nursery habitat for them my

  • name is Chris Lowe a professor of marine biology and the director of the shark

  • lab at Cal State Long Beach so this new project that we've embarked on is a

  • survey study where we're shooting video transects along the beach so the goal is

  • to come up with what we'd call an encounter assessment who's most likely

  • to encounter sharks and under what conditions and then we can also use that

  • same video footage to look at how sharks behave when they're in close proximity

  • to people are attacking aggressively are they attracted to people are they

  • repelled by people or do they just ignore people so we have hours of

  • footage of people in the water surfing swimming sharks swimming right by them

  • sometimes right underneath them and completely ignoring them they don't

  • change their speed they don't change their heading they don't turn around and

  • come back when we show that video footage to people they're astounded

  • because it doesn't match what they think of as encountering a shark so we're

  • right in the middle of a two-year study and hopefully by the end of this study

  • we'll be able to answer those questions

  • so one of the challenges of doing a large-scale study like this is you end

  • up with hundreds of hours of video footage that somebody would have to

  • screen through so by working with engineers computer scientists we're

  • developing machine learning algorithms that will go through and identify

  • surfers stand-up paddleboarders boogie boarders swimmers waders and then the

  • software will automatically identify those and then measure their distance to

  • the wave break into the shore line so to my knowledge this has never been done at

  • this scale so if we can develop those predictive models here the goal should

  • be we can do this anywhere in the planet

  • we've been studying juvenile white sharks in Southern California for about

  • 15 years now we've tagged over 80 sharks right now that have active transmitters

  • we have listening stations all along the shoreline from Santa Barbara all the way

  • down to San Diego so anytime the tagged shark swims within 300 yards of one of

  • our underwater receivers the receiver will log the time the date of the ID

  • number and then all the lifeguards or our partners can become subscribers to

  • that alert system so they will get text alerts or they'll get email alerts and

  • then they will use that information at their own discretion to decide whether

  • they want to pull people out of the water or not we also have an autonomous

  • underwater robot that we use to characterize the water column around

  • these beaches where we know the sharks are hanging out the robots also have

  • video cameras on them so as they're moving up and down through the water

  • we're videotaping the seafloor what's in the water column there's also on the

  • robot a receiver so it's listening for tag sharks while it's swimming along

  • doing its transects so this new technology coupled with our aerial

  • surveillance coupled with our tagging is doing something nobody else has ever

  • done before and giving us really high resolution information about why the

  • Sharks are here at this Beach and not that Beach and not that Beach so the

  • idea there is maybe with enough data we'll be able to predict why they're

  • here and where they're gonna be next

  • you

I'm out here with my team and we're doing surveys for sharks


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B2 中高級 美國腔

科学用无人机捕捉大白鲨和泳客之间的近距离接触(Science Captures Close Encounters Between Great White Sharks and Beachgoers With Drones)

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    joey joey 發佈於 2021 年 04 月 28 日