WEBVTT Kind: captions Language: en 00:00:02.720 --> 00:00:05.260 Predators are everywhere in the deep ocean. 00:00:05.260 --> 00:00:09.340 But until recently, scientists didn’t always know who was eating who. 00:00:09.340 --> 00:00:15.010 With unmanned vehicles and powerful cameras, they are uncovering these secrets. 00:00:15.010 --> 00:00:40.430 Some predators eat what they find, like this king crab. 00:00:40.430 --> 00:00:42.530 Sometimes prey becomes predator. 00:00:42.530 --> 00:00:56.610 This brittle star grabbed a tiny squid On 00:00:56.610 --> 00:01:04.960 our expeditions, many of the animal behaviors we see catch us by surprise. 00:01:04.960 --> 00:01:21.640 This burrowing fish hides before pouncing. 00:01:21.640 --> 00:01:32.600 Scientists control this remotely operated vehicle from a ship above. 00:01:32.600 --> 00:01:44.330 In an instant, this big wreckfish has made a meal of one unlucky shark. 00:01:44.330 --> 00:01:45.760 The wreckfish was fast. 00:01:45.760 --> 00:01:48.299 But there are also slow-motion predators. 00:01:48.299 --> 00:01:52.410 This starfish is stripping food off this branch of deepwater coral. 00:01:52.410 --> 00:01:57.550 It may take several months – or even a year - to finish this meal. 00:01:57.550 --> 00:02:03.630 Seeing these predators in action helps scientists understand the how ocean ecosystem fits together. 00:02:03.630 --> 00:02:06.310 And it is pretty amazing to watch! 00:02:06.310 --> 00:02:13.000 Now, let’s hear from an expert who studies these deep sea predators, marine biologist 00:02:13.000 --> 00:02:15.830 Scott France…..along with our host, Debi Blaney. 00:02:15.830 --> 00:02:23.200 Hello, I'm Debi Blaney, and I work for NOAA's Office of Ocean Exploration and Research. 00:02:23.200 --> 00:02:27.530 And today, I have the distinct pleasure of talking to Scott France. 00:02:27.530 --> 00:02:31.670 Scott is a marine biologist and professor at the University of Louisiana at Lafayette. 00:02:31.670 --> 00:02:35.959 He has been involved in our deep-sea exploration work for many years. 00:02:35.959 --> 00:02:36.959 Hi, Scott. 00:02:36.959 --> 00:02:38.450 Thank you for joining us today. 00:02:38.450 --> 00:02:39.450 Hi, Debi. 00:02:39.450 --> 00:02:42.500 Nice to virtually join you today. 00:02:42.500 --> 00:02:46.880 We just saw some impressive examples of predators eating their prey in the deep ocean. 00:02:46.880 --> 00:02:50.960 And the scientists seemed pretty surprised by what they observed. 00:02:50.960 --> 00:02:53.310 Why haven't we seen scenes like these before? 00:02:53.310 --> 00:02:56.500 Yeah, we're always excited to see that kind of stuff. 00:02:56.500 --> 00:03:04.690 And there are two primary reasons, and it's technology development and technology availability. 00:03:04.690 --> 00:03:09.810 Cameras for use in the deep-sea were really only first being developed in the late 1960s 00:03:09.810 --> 00:03:14.930 and 70s, and then remotely operated vehicles for scientific use really weren't common until 00:03:14.930 --> 00:03:17.200 the 1990s. 00:03:17.200 --> 00:03:23.000 We've had human occupied submersibles dedicated to science since the 1970s, but for a long 00:03:23.000 --> 00:03:25.820 time, there were only one or two in operation. 00:03:25.820 --> 00:03:30.590 And so, as you can imagine, demand for the use was really high, and the missions are 00:03:30.590 --> 00:03:36.330 so focused on a specific objective that we didn't have the luxury of time to survey for 00:03:36.330 --> 00:03:38.150 interesting behaviors. 00:03:38.150 --> 00:03:44.910 So basically, as more programs develop deep-sea capable remotely operated vehicles, ROVs, 00:03:44.910 --> 00:03:47.440 we have more opportunity for observations. 00:03:47.440 --> 00:03:53.360 And so, the Okeanos Explorer program, in particular, is well suited to these sorts of observations 00:03:53.360 --> 00:03:59.300 because they conduct these dedicated exploration dives that use high resolution cameras. 00:03:59.300 --> 00:04:04.100 And importantly, they pay careful attention to lighting the environment that gives us 00:04:04.100 --> 00:04:07.220 this opportunity to see these rare events unfold. 00:04:07.220 --> 00:04:12.790 And I think another important aspect is that the Okeanos Explorer program makes all its 00:04:12.790 --> 00:04:15.830 observations and data publicly available. 00:04:15.830 --> 00:04:19.549 And so whatever scientists see, so too does the public. 00:04:19.549 --> 00:04:23.870 There's a lot of hours of observation of the deep-sea that have been recorded there in 00:04:23.870 --> 00:04:28.480 the research archives, and so they're not easily viewed by the public. 00:04:28.480 --> 00:04:29.680 Yeah, you’re absolutely right, Scott. 00:04:29.680 --> 00:04:33.889 We're really, really deep and it's very dark down there and there's no natural light. 00:04:33.889 --> 00:04:38.850 So, having powerful lights will help us observe the environment. 00:04:38.850 --> 00:04:43.170 What are some of the tricks predators use to find and catch their prey when we're talking 00:04:43.170 --> 00:04:44.320 about the deep-sea? 00:04:44.320 --> 00:04:48.400 Well, the first thing you have to consider is there's no sunlight in the deep-sea. 00:04:48.400 --> 00:04:52.479 So, the answer typically won't be related to vision. 00:04:52.479 --> 00:04:56.350 Probably the most important sense in the deep-sea would be chemo sensory. 00:04:56.350 --> 00:05:02.520 Basically, the sense of smell detecting chemicals that are associated with prey in the water. 00:05:02.520 --> 00:05:07.800 And once the predators get that scent, then it's just a matter of tracking down that scent 00:05:07.800 --> 00:05:09.160 to its source. 00:05:09.160 --> 00:05:14.850 So, most predators tend to move upstream into our current to find the prey because the scent 00:05:14.850 --> 00:05:17.729 is coming downstream. 00:05:17.729 --> 00:05:23.130 Many predators can also detect motion in the water, movement in the water, basically pressure 00:05:23.130 --> 00:05:25.290 waves caused by swimming. 00:05:25.290 --> 00:05:30.080 Even sea anemones are able to detect pressure waves and they change how their little steam 00:05:30.080 --> 00:05:36.530 cells fire based on the pressure waves, and their knowledge of what's the size of the 00:05:36.530 --> 00:05:37.530 prey. 00:05:37.530 --> 00:05:41.860 You'll see shrimp and other crustaceans with these very long antennae that stream far from 00:05:41.860 --> 00:05:42.860 the body. 00:05:42.860 --> 00:05:46.990 Those would have sensory cells to detect the chemicals and the motion. 00:05:46.990 --> 00:05:49.020 And one of my favorites is the tripod fish. 00:05:49.020 --> 00:05:55.120 The tripod fish have modified fins that allow them to be propped up on the seafloor. 00:05:55.120 --> 00:05:59.789 And they have these long, thin rays that extend forward, kind of like a radar dish. 00:05:59.789 --> 00:06:06.490 And they're just kind of, I think, sensing motion, perhaps also chemo sensory smells. 00:06:06.490 --> 00:06:11.160 And once they detect something, they'll swim off to get it. 00:06:11.160 --> 00:06:18.480 Anglerfish have specialized lure right over the mouth, and sometimes those lures glow 00:06:18.480 --> 00:06:20.070 and that'll attract the prey. 00:06:20.070 --> 00:06:22.039 And they can feed on them. 00:06:22.039 --> 00:06:28.889 And some siphonophores, these colonial jellyfish like animals, also have bioluminescent lures, 00:06:28.889 --> 00:06:35.010 as well as stinging capsules that they use to paralyze prey such as small fish that get 00:06:35.010 --> 00:06:37.539 close enough to them. 00:06:37.539 --> 00:06:44.110 But we can also look at a lot of animals like corals and basket stars and sea lilies and 00:06:44.110 --> 00:06:50.889 even some sea cucumbers that basically can employ a strategy that's like a spider's web. 00:06:50.889 --> 00:06:56.319 That is, they're creating some kind of barrier in the water current that prey are going to 00:06:56.319 --> 00:06:57.319 run into. 00:06:57.319 --> 00:07:03.310 And these can be tentacles that can be arms, spines, even sheets of mucus. 00:07:03.310 --> 00:07:06.360 And this is why corals grow up into the water. 00:07:06.360 --> 00:07:10.990 They want to get their polyps that have the tentacles off the bottom because at the bottom, 00:07:10.990 --> 00:07:12.550 water isn't moving. 00:07:12.550 --> 00:07:15.569 And so, they get it up into the faster flow. 00:07:15.569 --> 00:07:19.830 And that's also why you see a lot of other animals climbing up on corals. 00:07:19.830 --> 00:07:23.260 They're basically hunting from the perch that is the coral. 00:07:23.260 --> 00:07:24.260 Wow. 00:07:24.260 --> 00:07:25.550 That's very interesting. 00:07:25.550 --> 00:07:30.210 And how do prey avoid their predators or escape them? 00:07:30.210 --> 00:07:33.200 Yeah, that's a tough living. 00:07:33.200 --> 00:07:37.600 Some prey have very powerful muscles that they use for rapid escape. 00:07:37.600 --> 00:07:40.190 Good examples of that would be squat lobsters and shrimp. 00:07:40.190 --> 00:07:43.950 They have these muscular abdomens that they can tuck underneath them. 00:07:43.950 --> 00:07:48.830 And then they dart backwards, hopefully away from the prey…excuse me…away from the 00:07:48.830 --> 00:07:51.110 predator, and not to the predator. 00:07:51.110 --> 00:07:53.669 Some species have a tube that they can retract into. 00:07:53.669 --> 00:07:55.770 This is very common among worms. 00:07:55.770 --> 00:08:00.539 And there's even one group of worms that's evolved to live with deep-sea octocorals such 00:08:00.539 --> 00:08:05.240 that the coral secretes a tunnel and the worms live in a tunnel. 00:08:05.240 --> 00:08:09.870 And so, you can find one colony of corals with about 100 different worms all living 00:08:09.870 --> 00:08:13.600 protected in their little tunnels. 00:08:13.600 --> 00:08:19.220 Other species will dig burrows into the sea floor that they can quickly retract into. 00:08:19.220 --> 00:08:24.060 This behavior has really surprised some ROV pilots who attempt to sample a sea pen colony 00:08:24.060 --> 00:08:29.919 that suddenly disappears into the sea floor when they sense the vibration. 00:08:29.919 --> 00:08:34.409 And then there are specialists that like to distract predators. 00:08:34.409 --> 00:08:40.229 For example, there are some squid that will release ink and mucus and that sort of combines 00:08:40.229 --> 00:08:44.139 and it forms something they call a pseudomorph that just kind of hangs and drifts in the 00:08:44.139 --> 00:08:49.689 water, that inky mucus, and so the predator goes there while the squid takes off in a 00:08:49.689 --> 00:08:50.689 different direction. 00:08:50.689 --> 00:08:51.689 There are even some deep-sea swimming worms that produce bioluminescent light, excuse 00:08:51.689 --> 00:08:52.689 me, I’m going to say that again. 00:08:52.689 --> 00:08:53.689 There are even some deep-sea swimming worms that produce bioluminescent light in structures 00:08:53.689 --> 00:08:54.689 that fall off the worm. 00:08:54.689 --> 00:08:55.689 So, the predator might chase the light ball while the worm swims away in the dark. 00:08:55.689 --> 00:08:56.689 So that's pretty cool. 00:08:56.689 --> 00:08:57.689 Oh, I did not know that, I had no clue. 00:08:57.689 --> 00:08:58.689 Swimmer. 00:08:58.689 --> 00:08:59.689 So how is predatory behavior in the deep ocean different from, say, the jungle? 00:08:59.689 --> 00:09:00.689 Probably the biggest difference is the density of animals is much lower in the deep sea. 00:09:00.689 --> 00:09:01.689 So, on average, things are really widely spread out. 00:09:01.689 --> 00:09:02.689 The probability of a chance encounter between a predator and a prey is therefore pretty 00:09:02.689 --> 00:09:03.689 low. 00:09:03.689 --> 00:09:04.689 And this is why predators really have to rely on these senses like humans, sensory or smell, 00:09:04.689 --> 00:09:05.689 in order to find their prey. 00:09:05.689 --> 00:09:06.689 And that low probability is why, historically, we don't often get to see many of these predator-prey 00:09:06.689 --> 00:09:07.689 events, which is why it's so great that we have so many opportunities now. 00:09:07.689 --> 00:09:08.689 And why is it important for us to learn about predators who prey in the deep ocean? 00:09:08.689 --> 00:09:09.689 Well, ultimately, all living organisms, including animals, need energy to survive. 00:09:09.689 --> 00:09:10.689 Prey is energy for predators. 00:09:10.689 --> 00:09:11.689 Humans are predators. 00:09:11.689 --> 00:09:12.689 Some of our prey, like many fish, are predators of smaller animals. 00:09:12.689 --> 00:09:17.320 And to understand how communities and organisms function, we need to understand who is eating 00:09:17.320 --> 00:09:18.790 who. 00:09:18.790 --> 00:09:23.319 Understanding predator prey relationships is an important step in the conservation of 00:09:23.319 --> 00:09:25.370 any community. 00:09:25.370 --> 00:09:31.000 But there's a bigger picture answer, and that is the flow of carbon and carbon compounds 00:09:31.000 --> 00:09:33.309 through our ecosystem. 00:09:33.309 --> 00:09:40.649 Carbon compounds are the key molecules for holding and transferring energy among organisms, 00:09:40.649 --> 00:09:44.519 and lots of carbon is bound up in the tissue of organisms. 00:09:44.519 --> 00:09:49.290 Of course, carbon compounds are also causing problems for our climate as they build up 00:09:49.290 --> 00:09:50.809 in our atmosphere. 00:09:50.809 --> 00:09:56.420 But the marine ecosystem is actually able to absorb a lot of that carbon. 00:09:56.420 --> 00:10:01.199 And so, it's important for us to know basically where is that carbon going. 00:10:01.199 --> 00:10:06.569 In the marine ecosystem and by understanding predator prey relationships, we have a clearer 00:10:06.569 --> 00:10:09.649 picture of how that carbon is moved through the ecosystem. 00:10:09.649 --> 00:10:10.649 Awesome. 00:10:10.649 --> 00:10:15.350 And we saw several scenes of predator prey behavior that were really fast, the shark 00:10:15.350 --> 00:10:18.079 going after the swordfish, the grouper going after the shark. 00:10:18.079 --> 00:10:23.170 But we also saw a scene of a sea star feeding on a coral. 00:10:23.170 --> 00:10:25.420 And I know that can be a very slow process. 00:10:25.420 --> 00:10:27.769 Can you talk more about that? 00:10:27.769 --> 00:10:32.209 Yeah, in general, a lot of processes in the deep sea are fairly slow. 00:10:32.209 --> 00:10:33.660 The deep sea is very cold. 00:10:33.660 --> 00:10:36.449 The average temperatures are below four degrees Celsius. 00:10:36.449 --> 00:10:38.750 It's like the temperature in your refrigerator. 00:10:38.750 --> 00:10:41.089 And that means metabolism is low. 00:10:41.089 --> 00:10:44.259 That's basically the generation of energy that keeps you alive. 00:10:44.259 --> 00:10:47.730 And if that's low, the pace of life is very slow. 00:10:47.730 --> 00:10:52.519 When you eat a meal, it takes a very long time for it to digest. 00:10:52.519 --> 00:10:57.670 And so, there are many species that have actually sort of adapted the strategy where they will 00:10:57.670 --> 00:11:02.009 have a big meal and then they can rest for weeks or even months. 00:11:02.009 --> 00:11:07.899 So, we made these observations of sea stars feeding on corals and we've had the opportunity 00:11:07.899 --> 00:11:11.540 to go back to the same coral after 18 months. 00:11:11.540 --> 00:11:16.269 And we've seen that the sea star has really only moved a few inches and is still feeding. 00:11:16.269 --> 00:11:22.089 So that means one predator is feeding on the same prey for more than a year. 00:11:22.089 --> 00:11:26.769 And that's just because it's taking a very long time to digest. 00:11:26.769 --> 00:11:29.540 So one meal lasting a year and a half or longer. 00:11:29.540 --> 00:11:32.549 Yeah, that's quite a refrigerator. 00:11:32.549 --> 00:11:34.470 That's pretty cool. 00:11:34.470 --> 00:11:37.379 Is there anything else you want to share with us today? 00:11:37.379 --> 00:11:43.699 Just, I hope everyone watching the Okeanos Explorer videos derives as much pleasure as 00:11:43.699 --> 00:11:45.279 deep-sea scientists do. 00:11:45.279 --> 00:11:51.290 Certainly, our objective is to learn as much as we can about this vast underexploited ecosystem. 00:11:51.290 --> 00:11:54.779 But we're all fans of this amazing and spectacular imagery. 00:11:54.779 --> 00:11:56.170 So please enjoy. 00:11:56.170 --> 00:11:59.700 Thank you, Scott, and good day to you. 00:11:59.700 --> 00:12:00.760 Bye Debi.