Giant Manta Rays of San Benedicto | Blue Realm | Free Documentary Nature

[Music] these graceful and majestic creatures are manta rays in an isolated corner of the globe the enormous animals approach and interact with humans and where there are mountains there are sharks [Music] a close relative of sharks manta rays have highly developed brains and appear to possess unusual intelligence researcher dr. Robert Rubin studies the fascinating behavior and biology of mantis and the best place to find them is 250 miles southwest of the tip of Mexico's Baja Peninsula these are the Giants of San venediktov [Music] [Applause] [Music] [Music] [Music] [Music] most fish are cold-blooded and are not generally considered intelligent manta rays however appear to be warm-blooded have very large brains and are perhaps even smart the giant animals were once called devil fish because their cephalic fins resembled the horns of a devil now known to be harmless filter feeders manta rays prey on nothing larger than tiny fish and plankton [Music] sometimes measuring over 20 feet across they glide through the water like seabirds on an ocean breeze [Music] manta rays are elasmobranch fish whose skeletons are made of cartilage rather than bone they are essentially modified sharks but unlike sharks manta rays have highly developed brains the largest of any fish in behavioral terms they are far more advanced than their shark cousins found primarily in tropical waters mantas also occur in cooler subtropical and occasionally even temperate seas these ocean voyagers are definitely not your average fish razor for the most part flattened sharks they have all the characteristics of sharks with the exception of the fact their bodies are flattened from top to bottom they differ from sharks and if they live most of their lives on the bottom as opposed to living in the open ocean manta rays are somewhat different than the classic description of the race in that they're very large in size they've appeared very recently evolutionarily and like sharks they're pelagic that is they swim in the open ocean evolutionarily sharks are a very old group and they appeared about 350 million years ago and for a long period of time sharks were the only cartilaginous fish on earth during the Triassic period most sharks experienced a worldwide extinction during a period of time when the seas were not highly productive there wasn't much food and when they reappeared a number of millions of years later raised also appeared and so raised are much more recent than sharks as a group and the mantas are the most recent there appear first in the fossil record about 20 million years ago dr. Robert Rubin is a college biology professor and also one of the world's foremost authorities on Ray's not teaching in central California he spends much of his time studying the enigmatic animals his passion unraveling the mysteries of this little-known giant I was attracted to mattress when I first saw them in the southern Sea of Cortez 30 years ago I doubt that I've ever seen an animal that has more charismatic grace and elegance as a biologist we become very curious about animals at the extremes I've always been interested in animals that seem to be pushing either environmental limits or evolutionary limits the beauty and the grace of the end I'm all coupled with the fact that almost nothing was known about them and the fact that they seem to live in a very unusual environmental niche can't help but attract the curious biologist mantas have a great deal in common with many species of sharks especially large filter feeders such as basking and whale sharks similarities between the two groups also extend to their preferred foods and habitats manta rays that a number of species of sharks are almost always found to coexist in similar habitats and in large part this is a function of the availability of food most of these offshore reefs and underwater sea mounts experience extensive periods of upwelling it increases the nutrient quality of the water and the food chain begins with that and so there's always food and as the food goes the Mantis and the Sharks go is one large pelagic community following the food dr. Rachel Alexander's studies the biology of manta rays at her lab in Cape Town South Africa she made an unusual discovery a large devil ray had washed up at one of the local beaches here in Cape Town and while we were working this animal up I came across a large network of blood vessels in the pectoral fin the structure of this plexus suggested that it was used to warm the swimming muscles of the animal which indicate that the species of rain is warm bodied [Music] many scientists believe the evolution of blood warming in wide-ranging species such as manta rays is related to a phenomenon called niche expansion most fish that are cold-blooded don't venture very far from their preferred habitat but when body temperatures are elevated above those of the surrounding sea animals can migrate into colder waters these rights have been known to occur in differing water temperatures colder waters than normally expected for these animals that live in tropical and subtropical regions there's even an unconfirmed report of manta occurring more so Falasca manta rays appear to heat not just their bodies but their oversized brains as well manta rays have extraordinarily large brains when you scale them to their body size in fact their brains are not too dissimilar to what you'd expect for a mammal of that size not a fish and as we look at the brains we see that not only are they large in size but the specific areas that are expanded to make the margin size are the same areas that are expanded in the mammalian brain recent work has supported the fact that they're probably maintained at a higher temperature so it's a huge step evolutionarily and has allowed them to occupy areas in the world that other Ray's couldn't be successfully where is the best place in the world to study mantis and how do you track their movements through the sea to study manta rays a team of researchers and filmmakers traveled to the southwestern tip of Mexico's Baja Peninsula the region is a busy tourism and sport fishing destination and the gateway to the remote sapporo islands in cabo san lucas the scientists and high-definition video crew boarded the live-aboard diving vessel Sol Mar 5 2014 [Music] the microbiologist dr. Gavin Chilcott and veteran cinematographers Tom Campbell and Dennis Kaufman before departure Ruben and Chilcott prepared their research tools including acoustic surveillance equipment [Music] Gavin and I built a PVC cage that would fit over one of the skiffs sides that we could attach a hydrophone to that allows us to actively track the animals around the island so we can use the tags in an active way by following them in the skiff with a hydrophone and so it gives us a daily pattern of the animals movements after a 24 hour 250 mile journey Southwest the expedition reached San Benedicto island and the Sakura archipelago desolate and inhospitable the islands offer little refuge and have been spared the ill effects of human settlement the isolated region is however a beacon to sharks whales and other pelagic animals [Music] the barren islands are part of a volcanic undersea mountain range that includes the Galapagos Islands lonely outposts in the open Pacific they rise thousands of feet from the seafloor while there is little sign of life above the surface the surrounding sea teams with activity volcanic spires swarm with schools of fish upwellings of cold nutrient-rich water deliver a steady supply of plankton and where there is food sharks and rays are sure to follow [Music] the main islands in the group San Benedict Oh Clarion and Socorro are spread out over hundreds of square miles Bob Rubin has made dozens of trips to the archipelago Sam Benedicto Island in particular is arguably the best place on the planet to study the giant waves we're now into about the 20th year of working on these animals and about the fifteenth year of working at San Benedetto we've chosen salmon a dick though as a study site because it certainly is unique in the major locations in the world where mantas are found and the mantas numerically are found in greater abundance here than anyplace else in the world that I know of and they come back so it allows us to take a look at them over a long period of time [Music] at San Benedicto Island Bob Rubin and Gavin Chilcott explore recent evidence of volcanic activity the geologists figure that this has been formed in three major events once the big cone came up and then volcanic dust and then Riesling 19:52 this whole lava flow just broke out in here split out the side and flowed into the Oakland water this turns out to be one of the more interesting places in the world so new that you can study the formation of land plant communities marine communities the first time I came here there was no vegetation on the island at all except some gourds [Music] I've always really liked Islands and they're really enchanting this one I've been on a lot of oceanic Islands but I think this one is one of the most charismatic and intriguing for me it's just so another landscape from another time one of the main goals of the expedition was to track mantas with high-tech acoustic tags the devices would allow the researchers to monitor the animals movements and provide a wealth of other valuable data [Music] recently in an effort to find out more about manta movements and the way in which these specific habitats we've begun to apply small acoustic tabs that allow us to track the animals by using underwater listening stations listening stations are receivers that are placed at various locations in the habitat around the island and our running continuously [Music] as the animals swim by they pick up a pink from the tag that's been attached the animal and recorded and so it gives us a pattern of when animals are in the habitat what the water temperatures are like when they're there and also how frequently they're there often these shallow bays are places in the morning particularly manses will come in and move around these bays interestingly in later afternoon they seem to go around from point to point actually what we want is we want to be as close to the tip of the lava flow right there as we can get to get a to get at least one good mark on the GPS analyzing the data has shown us that the animals are present somewhat infrequently and for a period of time that the tags have been out in the animals have been reported they're only in the habitat about two percent of the time the rest of the time they're away from the island and they may be moving between islands they may be in deep water we're not sure where they are but we know that they're not close to the listening stations we also have found that they're primarily animals of the early day during the night we have very very few hits from our stations suggesting that during the daylight hours they're present and during the dark hours they're not around the island of Paul behind this lava flow we just got several pretty strong signals and then they're gone now guesses going in and out of those troughs come get a signal and go back in again let's go see to find out where the Rays migrate when they are away from the islands ruben utilizes a new tagging system based on satellite technology the devices are attached to the animal's body where they begin to acquire and store information after gathering data for up to a year the tags are pre-programmed to detach and float to the surface they then search for a satellite and after receiving a strong signal begin downloading information the tags record a number of factors including water temperatures dive depths locations and in some cases even swimming speeds satellite monitoring is a dramatic leap forward in manta research satellite tracking will allow us not only to determine how the animals use the specific habitats that we know they're found in but also how they might move between islands and other habitats we may also see that there's a well-defined migratory pattern that connects groups of islands or different areas of the ocean that become critical areas to protect this particular tag we've set up so they don't come up on New Year's Day Newsday yeah Wow we'll we'll get the data we'll have the computer in one hand a bottle of champagne and the other yeah I'll give you a call this is the first time I've ever seen math is at this site and interesting enough one of the animals that we know from San Benedict oh we did see here 30 days later and that's the only other time that I've ever seen mantas at this site so we know that you between at least those two sites and a satellite tag will tell us a little more yeah maybe they follow some deep ridge liners maybe all these islands are on the same underwater Ridge system and that may be what they're using as a migratory cue yeah possibly why do manta rays approach and interact with humans and hitchhikers on their backs ready in the Sakura Islands it doesn't take long to find mantas drawn to the sound of boat motors the animals immediately approach and exhibit their renowned behavior even after 20 years of studying the Rays Bob Rubin is still amazed at how the animals port human company the interactions that exist between manta rays and humans are not only are curious but remarkable and I think it's fair to say that nowhere else in the world can people interact with wild vertebrates of this size in these numbers while vertebrate animals are not normally curious about him as except as potential predators or perhaps prey but mantas seem uniquely curious about human organisms to the point of courting the interactions coming very very close and making eye to eye contact and allowing humans to stroke them ride them pet them just about every possible type of contact that a person could make is not only possible but it seems to be promoted by the behavior of many of the animals [Music] the complexity of Manta brains suggests that they may be able to carry out a lot of higher functions that we normally associate with mammals and their behavior seems to reflect some of those characters I think it's fair to say that they're curious and curiosity to some degree is a sign of intelligence one of the most intriguing aspects of Manta and human interaction is that the animals appear to favor certain divers in simple experiments Ruben has attempted to discover how they choose their favorite playmates certain mantas will allow certain individual humans to come close while moving away from others and we wondered as to how they might be able to tell and so in small little experiments we've changed diving gear and they still are able to recognize the person that they would allow come close and the person that they reject and we also were able to show that by putting tinfoil in our masks where they couldn't see our eyes they no longer could tell who the person was they wanted to ride or the person they'd reject and so the speculation is that they're recognizing us by our eyes and their close proximity and the fact they come right next to you and look eye to eye may in fact support that mantas and other large pelagic animals play host to a strange fish called Lamora the hitchhiker's attach themselves to their rides with a specially adapted dorsal fin [Music] whale sharks such as this 45-foot giant are frequently covered with dozens of the fish the bigger the host the larger the size and number of remoras even a juvenile whale shark has to contend with the pesky freeloaders mantas are very much like a floating community in open water very big organisms like this attract a lot of other organisms that use manta ray see there is shelter protection from predators as a source of transport from one spot to another or perhaps even a guide to take any other species to food one of the organisms that exists in close association with mantas are large Remora fish that are sometimes called sucker fish it was thought for a long period of time that remoras were parasitic and war using the mantas as a point of attachment and cleaning the mantas to some degree symbiotically taking parasites and sawing off of their body or perhaps just picking up the scraps after a manta meal [Music] to investigate the relationship between the two fish we've enlisted the services of a free diver [Music] but catching one of the wily fish was no easy feat especially without scuba gear even if you do manage to grab on to them remoras iron grip make extraction difficult they do however make great handles for an exciting Manta ride [Music] you can see the disc and this is a this is a fin yeah this is the dorsal fin the same fin that you see in a shark it's just modified into a sucker and in a regular fish that the fin rays that go into the fin to hold it up have been modified here into these sucking arrangements they tie in then they pull into the skin and create a suction and also a grip you can feel the reverse spines here it's kind of like a gill but of course it's not and those are just the Rays of the fin the inside of the gills are overlapped they may be straining plankton in the same way the mantas are the Remora revealed an exciting discovery remoras like mantas appear to have their own hitchhikers these are copepod parasites they're very interesting probably unknown I would bet this species this is a new species these kinds of parasites are species specific so it could be that this kind of copepod parasite of this species is found only on Errol Morris there are similar copepods like this but they have much longer tail structures to tail like structures that have found the dorsal fins of sharks back at his lab Ruben made a more thorough examination of the unusual fish his findings have helped to disprove many long-held theories about remoras and their relationship with their hosts one of the things it's kind of interesting about him is that when you look at the mouth of the animal the mouth is just proportionately large has a really big mouth or a fish of this size and then you look at the gills of the animal here and see how large the gills are they're really big almost like the fish were some kind of a pelagic swimmer like a tuna among mantas and also among the great whales we see exactly this sort of thing that suggests that instead of feeding on fish as one might expect that they've been feeding on some kind of planktonic organism and I think this is a fairly reasonable verification of the fact that these animals are planktivores just like the mantas and they just use the manta rays as taxicabs to the restaurant a very unusual fish one of the great feats of evolutionary design in the marine world how do you tell mantis apart are they a potential source of new miracle drugs and what is the most popular attraction at one of the world's largest aquarium [Music] despite the fact that manta rays are very large in size and widely distributed relatively little is known about their biology or genetics all mantas are considered to be members of a single species although they are sometimes referred to as either a Pacific or Atlantic manta ray depending on where they're encountered [Music] the Rays also have two distinct body patterns manta rays occur in two different color types one of them with white on the back in a large V at the base of the dorsal fin and we call those Chevron mantas and others are solid black like large stealth bombers and we call those black mantas the black mantas are not found typically in warmer tropical waters whereas the chevron pattern seems to be the most common pattern worldwide individual manta rays like orcas and humpback whales have distinguishing characteristics these subtle and sometimes dramatic differences enable the researchers to utilize photo identification each animal has a different marking very much like an individual fingerprint by looking at the instance through time we've been able to establish that they don't change and so that once you have a photograph of an animals under surface you can enter it into a catalog and you can match a time after time new photographs we've identified now a hundred and forty-six individuals and of that 146 animals we've seen about forty animals more than once some of the animals we know for as long as 15 years the photo identification system allows us to get an estimate as to how big this population is and whether it's what biologists call an open or closed population and that really means our animals moving in and out of it from other sources or does this population represent one large group of animals that are genetically related like large families Bob Rubin and Gavin children's research includes DNA sampling of metal tissue these clues help the researchers piece together a difficult genetic puzzle acquiring a DNA sample requires a specially tipped spear that extracts a plug of tissue the size of a pencil eraser a quick jab from the sharp spearhead not unlike a mosquito bite secures the sample the difficult part is trying to catch the speedy Mantha's [Music] in sampling small amounts of skin and surface tissue we're able to bring that tissue back to the laboratory and analyze the sequences in the DNA of the cells those sequences when compared to other samples will tell us the kinship similarities between individual mantas and also between groups of mantas for example those found in one group of islands as opposed to those found in another [Music] why that was about the most cooperative Manta boy no kid he'll ever find in your life yeah that was successful despite a false start there you didn't get the DNA sample in the first go well the tissue didn't retain we did get a good punch but this she didn't didn't come out with tip and I'm not sure why so we changed the tip and second tip was successful but you get a good sample got a good sample the research team also collected samples of the mucus coating of mantas the potential healing properties of the mucus may one day be the source of new wonder drugs elasmobranch is a group the Sharks in the race seemed to have a remarkable capacity for wound repair and tissue regeneration manta rays are covered with a very fine mucus film one of the new things we've become interested in is the role that this mucus might play in protecting manta rays from pathogens from bacterial invaders and so recently we've collected some of this mucus and brought it back for laboratory analysis it's possible that mucus is of this type may have antibacterial qualities not only for the mantas but also for human skin as well and it's theoretically possible things like this could be produced by pharmaceutical companies and used to enhance wound repair and decrease the potential for infection we know that we've extracted a lot of natural products drugs and things that have been very useful in the human addition for optical rainforests and the sea seems to be the next frontier for that the Atlantis Resort and Casino in the Bahamas boasts one of the world's largest aquariums and the number one attraction for the past few years has been bubbles an Atlantic manta ray of course sharks are top draw for visitors but their graceful cousin consistently ranked as the guest favorite are sharks I'd say rate number two in terms of attraction for the guests and what outranks the Sharks for us is our impressive manta ray that we have right here in the ruins tank that's always the biggest draw for the guests is to watch the manta ray and because of the size right now this one that we have in the tank is just over 13 feet and with bubbles easily acclimatized to our new surroundings but the Darin feeties she dramatically increased in size once bubbles reached a wingspan of almost 15 feet it was clearly evident that she had outgrown or artificial home a reluctant decision was made to release her back into the wild [Music] capturing and transporting such a huge animal was no easy feat timing was critical and a helicopter waited on standby released within just a few minutes she quickly bolted into the dermis basically she just outgrew the aquarium they grow really quick they almost double their size in the first year so we had to release her it went very well was a great effort great team effort a few days later a six-foot juvenile Manta was caught off Rose Island like bubbles before her the new Rae appropriately named Rose will be a top attraction at Atlantis how does such an endearing animal find itself on an endangered species list in February 1994 members of the conservation group Seawatch visited the Socorro archipelago they were there to scuba dive and snorkel with the famed mantas on Valentine's Day Mexican fishing boats appeared and started pulling in nets on the southern tip of sand and addictive Island mantas that the group had been interacting with the day before were hopelessly trapped in gill nets the entangled rays destroyed valuable fishing gear and enraged fishermen killed the animals [Music] see watch brought the disturbing video footage to the attention of the mexican media influential television programs began airing the story and networks from around the world quickly seized on the dramatic images [Music] the footage was brought to the attention of the head of fisheries and the Mexican president government and public reaction was swift within two months the pacific manta ray was put on an endangered species list it is now a crime to kill a manta ray in mexico the islands are highly desirable as a fishing ground because they are so highly productive and in the recent past fishermen have used the islands to take large quantities of bill fish sharks and a variety of other species including manta rays manta rays were taken rather indiscriminately and killed rather viciously by fishermen because they were contaminating the nets mantas worldwide need protection because as you look at them biologically their first large animals that don't reach reproductive maturity until late in life that's true of most sharks and race they are also characterized by giving birth to a single pup and so it's then likely that a single female will give birth to maybe only 10 or 12 pups in their entire lifetime [Music] large animals like mantis can't survive without a conscious human conservation ethic [Music] today spectacular one black one and two Chevron one so we got a very good measurement of one complete measurement of both the width and the length after nearly a month of C it was time to return to Cabo San Lucas for Bob Rubin and the rest of the team leaving was bittersweet but the expedition revealed many Newton sites into Manta biology distribution and behavior after returning to his lab at Santa Rosa Junior College Ruben began to receive results from his satellite tagging program we recently received information from to tax that had been out for approximately a month and it translates into eight hundred and ninety pages of data speculation suggests that these animals are probably well away from the island in deep water and all the indications that we have implied that the animals move away from now and ignite into deep water to feed and then return to the island during daylight hours and we know that in some cases we've seen animals at one Island within a few days to several weeks we see the same animal one hundred kilometers away the animals are present for a few years at a time and then often gone for several years at a time so they may be perhaps thousands of miles away from these sites during other times of their life history and the satellite tags will allow us to identify those trends the Sakura archipelago and nearby Sea of Cortez were up until recently some of the richest waters on earth the undersea ecosystem in the region is now in danger of collapse industrial-scale gillnetting dramatically depletes resources and when fishing boats discard damaged Nets they continue to kill sharks sea lions and mantas are no match for the nearly indestructible lines long lining produces a huge bycatch of non-targeted species almost all the fish and other animals caught are incidental worthless to fishermen and Asians a man for shark fin soup fuels a wasteful industry there is hope due to the conservation efforts of groups such as sea watch and the save our seas foundation and scientists like Bob Rubin mantas have a fighting chance of survival the Socorro archipelago is now a protected biosphere of Mexico manta rays are one of the most incredible organisms the planet has ever spawned and to watch them to be around them to have the ability to study them and know more about their biology is exciting beyond belief I'm very optimistic about the future because I think some of the work that we're doing and the work of others will result in a much better understanding of who they are and how important they are in the structure of pelagic communities and in the world's oceans this whole [Music] working with manners is one of those exciting things that anybody could do and I love doing it every day I hope to continue to do it as long as I'm here and as long as they're here and I hope that they're here a lot longer than I am [Music] [Music] [Music]

Channel: Free Documentary - Nature

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Keywords: Free, Documentary, Documentaries, adventure, nature, nature documentary, documentary - topic, documentary (tv genre), ocean documentary, sealife, blue realm series, manta ray, manta ray documentary, marine life, marine life documentary, the bahamas, bahamas, caribbean, pacific ocean, diving, diving documentary, sharks, shark diving, shark tourism, pacific ocean documentary, Wildlife, Ocean Life, Ocean, Batoidea, Rays

Id: YVm_Ar4QwTY

Length: 47min 0sec (2820 seconds)

Published: Sun Apr 19 2020