For the biggest fish in the sea, whale sharks (Rhincodon typus) are rather elusive. Aside from a few known feeding aggregation sites, which are mostly frequented by juvenile males, baby whale sharks, adults, and females whale sharks are rarely seen.
Whale shark feeding sites have been identified in Isla Mujeres Mexico, Mafia Island in Tanzania, also Madagascar, Tofo Mozambique, the Philippines, Seychelles, and Thailand. But still, only juvenile males have been counted in these sites.
There are some exceptions to this general rule, however, where we find huge pregnant momma whales sharks. These are generally offshore seamounts or volcanic islands. Adult females are typically found in oceanic waters around or outside the 200 m isobath, where the ocean is 200m deep, while juveniles tend to stick to shallower nearshore coastal water.
Whale Shark Conservation
Dr. Simon J. Pierce has the job we all dream of. He is the world’s top whale shark conservation biologist and travels the world studying these gentle giants. Identifying whale sharks populations outside of their familiar aggregation sites is important for the conservation of this globally endangered species.
One of the best places in the world to see gigantic pregnant female whale sharks is 300km from the nearest town, around Darwin Island, Galapagos. Whale sharks normally spend less than a day at Darwin Island not to feed but most likely to calibrate their built-in GPS.
Historical volcanic eruptions at Darwin have created concentric rings of magnetically polarised rock on the seafloor, providing a detailed relief map for animals.Whale sharks are acutely attuned to the Earth’s magnetic field and they use these oceanic seamounts as a way to calibrate their internal compass.
But here is the problem. Darwin Island is remote, and it’s hard for Simon and his team to visit Darwin for more than a couple of weeks per year. Simon has dedicated his life to photographing, studying, and tracking whale sharks, but that doesn’t mean the average diver help too. Cue Wildbook an online photo-identification library for whale shark.
Whale sharks all have a unique pattern of spots, meaning that each individual is photo-identifiable. The Wildbook uses photographs of the skin patterning behind the gills of each shark, and any scars, to distinguish between individual animals.
In 2017 Simon and his team documented 7 new sharks over 36 dives, raising the total number of whale sharks identified from the Galapagos to 180.
However, none of these sharks have ever been re-sighted outside the Galapagos.
Where are the sharks going?
They generally swim right out into the Pacific Ocean, far from any landmass. There’s a long productive zone where cooler waters from the Peruvian coast meet warm tropical waters above the equator and, based on tracking data, the whale sharks are feeding out there. They’re also, most likely, giving birth in that area too.
In a recent newsletter from Simon he put out the call for scuba divers to submit their whale shark photos from the Galapagos to the global Wildbook database at www.whaleshark.org. Photos from visiting divers (from years past, too) are a huge boost to their research efforts.
Where sharks breed, and how often they are breeding is still an unknown. The more photos they receive the faster they can solve the whale shark mystery.
“I never would have thought it was a humpback whale so I didn’t really take the time to go over and try to locate it. Now, I’m very mad at myself.”
PANAMA CITY BEACH — It was nothing short of a “whaley” big surprise.
A passing fisherman didn’t even realize what he saw until later, but a Florida Fish and Wildlife (FWC) Officer in the area took a picture of the gray hump that surfaced offshore.
It was a humpback whale, both FWC and the National Oceanic and Atmospheric Administration confirmed.
“I never would have thought it was a humpback whale so I didn’t really take the time to go over and try to locate it,” said the fisherman Bob Bennett. “Now, I’m very mad at myself.”
He was he was about 12 to 15 miles offshore on Feb. 15 when a buddy he was fishing with, Dallas Doyle, said “what is that hump?” Bennet shut down his boat in time to see the whale dive back down, but didn’t see the humpback again after that.
In the winter months, juvenile humpback whales will head to Florida and often stay near shore, said FWC spokeswoman Rebekah Nelson said in an email. Normally, they stay in the Atlantic ocean, but occasionally they will make a detour.
“Like right whales, humpbacks are occasional visitors to the Gulf,” Nelson said. “We don’t expect to find them there regularly, but we are not surprised by the sighting either.”
She added, there is no reason to suspect the humpback was ill or injured.
While uncommon, this is the second time this year a whale has been spotted off Panama City Beach. In January, an endangered right whale was spotted swimming past the second sandbar, the first seen in Gulf of Mexico since 2006. There are less than 500 of them left.
While humpback whales were one of the original species listed under the Endangered Species Act, they are now off the list due to growing populations, according to the 2016 stock assessment.
A fully grown humpback whale weighs 25 to 40 tons, is up to 60 feet long and will live to be about 50 years old. They’re well known by whale watchers for their habitat of breaching — jumping out of the water — and slapping the water with their fins, tails and head.
Humpback whales — whose scientific name Megaptera novaeangliae means “big-winged New Englander” — spend the summer months building up fat stores in the rich feeding grounds such as the Gulf of Maine and Gulf of Mexico before heading south to tropical or subtropical waters in the winter months to breed. According to NOAA, they make the farthest migration of an mammal.
When I first took a freediving class, it was because of a colleague and good friend of mine. I mean, freediving is just snorkeling, but a bit deeper right? Oh, how I was wrong! Nine years and quite a few classes later I still love the world of freediving, and I base it all on the lessons that I learned in my early classes. The world of freediving is filled with misconceptions, misconceptions that taking a good quality freediving class can help clear up.
So, Physics and Physiology!
By understanding how the water impacts your physiology, you can change the way you think about freediving. I found this to be the key to opening up depth. We typically fear what we don’t understand, that relies on comfort. Increasing your knowledge on what’s happening to you while being at depth helps remove that evil monkey that sits on your shoulder telling you to turn around, allowing for a calm, relaxed state of mind and better dives.
Learning about breathing and recovery breathing was the next significant impact on my freediving. A reliable, evidence-based approach to breathing and recovery breathing can extend your dive times and deepen your relaxation.
When you’re researching where to take your freediving class the right instructor/facility. Having a reputable instructor that you vibe with.
In my personal experience, I have found that programs that are overseen by a facility tend to be more consistent in the information and knowledge in which they provide. Of course, this isn’t true of every program that is out there. But, by looking for programs that are overseen by a freediving facility you’ll have a higher chance that the program you are looking at keeps within agreed upon industry standards and the instructors that teach it is being held accountable for their level of instruction by someone other than themselves.
Ask your prospective instructor/facility how much time you get for practice and receive critique.
The last thing I suggest looking for in your instructor is their ability to teach equalization. Not just any equalization, but the Frenzel method. There are instructors out there that believe that teaching new freedivers to get by with the Valsalva method of equalization is ok. If your instructor can’t show you how to Frenzel, even in your level 1 class, then you are going to struggle to get to depths below 10m.
Freediving is an incredible sport. One that can change your life on both a physical and psychological level. After years of freediving, I still love it just as much as the first day I placed my head underwater. There’s something that’s deep within us that speaks to the ocean, but to hear it we first must quite our minds to truly experience what it has to say. Taking the right freediving class will not only help you improve your skills in the water but will allow you to do so safely, putting your mind at rest and opening the gate to a lifetime of freediving adventure.
Marine turtles, a resilient group of creatures that have been around for over 200 million years and survived mass extinction that wiped out the dinosaur, are today facing their gravest challenge yet. Nearly all species are classified as endangered – under threat from overfishing, pollution, habitat destruction and rising temperatures.
Members of a regional task force from Bangladesh, India, Maldives, Pakistan and Sri Lanka made urgent calls for a plan to stop the decline of the threatened species when they met in Colombo at the second meeting of The Northern Indian Ocean Marine Turtle Task Force (NIO-MTFF) at the end of January. The task force, comprising experts and government officials from each country, was set up by the Indian Ocean and South East Asia (IOSEA) Marine Turtle Memorandum of Understanding, an inter-governmental agreement under the Convention on Migratory Species (CMS). This provides a rare opportunity for conservationists from across the region – including India and Pakistan – to share experiences and for countries to work together towards a common goal.
Sharing country-specific experiences, the experts pointed out that the threats to their survival included fishing, poaching, habitat degradation and coastal development. Apart from adopting best practices from other countries, they also committed to enforcing relevant legislation and collaborating with each other on research initiatives, including satellite and flipper tagging.
“I think regional collaboration is a very important initiative,” said marine biologist Fehmida Firdaus, the only Pakistani with a doctorate in marine turtles. “We really need a task force like this for undertaking conservation programme.” A dearth of both manpower and financial resources make patrolling beaches or quality research impossible: “This regional cooperation will give impetus to both,” said the researcher, who retired from the Sindh Wildlife Department in 2014 having given over 30 years to marine turtle conservation and research.
Species under threat
Two of the world’s seven marine turtle species – the Olive Ridley and the leatherback – are ranked as ‘vulnerable’, according to the International Union for Conservation of Nature’s (IUCN) Red List of threatened species, while loggerhead and green turtles are classified as ‘endangered’ and the hawksbill and kemp’s ridley ‘critically endangered’. Data for flatback turtles remains insufficient.
On land, the threats discussed included the degradation of turtle nesting areas and development activity on the beaches, said Samar Hussain Khan, Deputy Conservator (Wildlife) at Pakistan’s Ministry Of Climate Change. Other threats included the hundreds of eggs that are destroyed and poached by people, dogs and other predators and the callous use of artificial light on beaches confusing both the nesting females and their hatchlings, leading them astray instead of towards the water or the hatcheries.
But the threats to turtles in the water are a more significant concern, said Umair Shahid, manager of the marine programme at WWF- Pakistan. “Our biggest concern was the by-catch and ghost nets [lost or abandoned fish gear] that posed a serious threat to the turtle population.” Getting accidentally caught in fishing nets and big trawlers is the biggest danger to the turtles.
“It is frustrating,” said Shahid, “that the lack of evidence and data keeps countries from taking robust decisions on implementing conservation and management measures to mitigate by-catch of sea turtles in fishing operations.”
While there is still a lot to be done to ensure survival of these magnificent animals, fishermen hold the “key for sustainable fishing, since they have been actively involved in the release of thousands of sea turtles alive from fishing gear,” said the WWF spokesperson.
In 2013, WWF-Pakistan started training fishermen to safely release sea turtles entangled in their nets. Since then about 20,000 sea turtles have been safely released. This has resulted in a major impact on the population of sea turtles in Pakistani waters.
At the same time, Firdaus hoped the government would declare nesting areas in Pakistan as protected areas. “Even if just 5 km of the 12 km area at the beach at Hawkesbay [near Karachi] becomes a turtle reserve and covered by legislation it will be wonderful,” she said. She also hoped the Sindh Wildlife Ordinance, which she helped draft in 2010 and continues to gather dust at the provincial assembly, will get a new lease of life.
But even enforcement of existing laws remains weak, lamented Khan, due to lack of awareness, limited inter-agency collaboration and financial constraints. Under various laws, it is illegal to hunt, kill or capture protected species. Even export and domestic consumption is prohibited.
In the 1980s, when Firdaus began visiting the nesting areas of the turtles, there were a few houses around the beaches; today, to her horror, “the place is swamped with housing colonies”.
“More people are seen visiting and have constructed beach huts there and hold parties till late in the night. They light up the place and make noise, play loud music and litter the place. How will the turtles lay their eggs?” She warned that if turtles are unable to nest, the ecosystem’s food chain will be broken. “If the turtle population decreases, the plankton and algae on which they feed in the sea will grow unabated.”
Olive Ridley turtles used to visit Pakistani beaches, but since 2013 no nesting has been reported, said Samar Khan of the Climate Change ministry. The WWF says that no nesting has been reported in the last 13 years. Even Firdaus cannot remember the last time she witnessed their nesting, though Khan claims they are reported in Pakistani waters in good numbers.
But this is nothing compared to the arrival Firdaus witnessed in Odisha, on India’s eastern coast, when hundreds come out of the Bay of Bengal en masse on to the beach, each one digging up a two-foot hole, depositing a hundred or so eggs and then awkwardly lumbering back into the water – a sight she will never forget.
In hot water
Along with the real and present threats, the task force meeting also touched upon the slow unfolding impacts of climate change and how associated rising temperature is causing an imbalance in the sex ratio in this reptile. Earlier this year a study published in Science Direct revealed that increased temperatures linked to climate change was leading to the ‘feminisation’ of green turtles in the northern Great Barrier Reef. Only about 1% of these juvenile turtles were hatching male. “…many sea turtle populations are in danger of high egg mortality and female-only offspring production” stated the study.
Pollution of the ocean by plastic was a key item on the Colombo meeting agenda. According to WWF, 8.8 million tonnes of plastic enters the ocean every year, the equivalent of a garbage truck dumping a full load every minute. Hundreds and thousands of turtles die each year from becoming entangled in or ingesting plastic and other waste.
“This is a planetary crisis,” the UN oceans chief Lisa Svensson had told the BBC. “In a few short decades since we discovered the convenience of plastics, we are ruining the ecosystem of the ocean.”
Along with the dumping of plastic, Shahid is concerned about the 450 million gallons of untreated waste from Pakistan alone going into the Arabian Sea every day.
HATTERAS INLET, N.C. – Members of the Coast Guard Station Hatteras Inlet released its third batch of sea turtles that were being rehabilitated after being cold stunned in December 2017.
“Sea turtles are a “Federally Protected” species and we work closely with several agencies to recover, rehabilitate and release them back into warmer waters,” said the Coast Guard Station Hatteras Inlet in a post on its Facebook page.
The agency that it worked with was the North Carolina Aquarium in Manteo.
42 sea turtles were released back in late December 2017 into the ocean on Roanoke Island by the NC Aquarium after being brought to their rehabilitation center because of a dip in ocean temperatures.
The NC Aquarium said that they received 100 sea turtles to its Sea Turtle Assistance and Rehabilitation (STAR) Center from December 10 to December 20 because the drop in temperatures cold-stunned the turtles. This means that they suffered hypothermia-like symptoms, which lowered their heart rate and circulation.
STAR Center staff said they treated the cold-stunned turtles by warming them slowly over the course of a few days. Some turtles required extended stays until they are fit to swim and fend for themselves, but others were cleared for release after a check-up by the NC Aquariums veterinary team.
“As long as they are swimming well, display no signs of injury, malnutrition or illness and pass a vet exam, they are OK for release,” said STAR Center Manager Amber White.
The NC Aquarium said that donations have helped them be able to care for the turtles, and that Coast Guard has also helped and will continue to help release turtles into warmer parts of the ocean.
An endangered baby beluga whale is getting a second chance at life thanks to rescue efforts from SeaWorld.
The beluga calf, named Tyonek, will live at SeaWorld San Antonio as the first-ever beluga whale from Cook Inlet, Alaska to be successfully rescued and rehabilitated.
Tyonek was found stranded in 2017 in Cook Inlet. He was less than a month old.
Experts from the Alaska SeaLife Center believe the whale had been stranded for several hours. He was in a weakened condition but did not show evidence of major physical trauma. It is likely Tyonek’s mother either abandoned him or died, so reuniting him with her was not an option.
Three animal care specialists from SeaWorld San Diego helped to nurse Tyonek back to health.
NOAA Fisheries selected the calf’s new home at SeaWorld San Antonio because it is the “location best suited for Tyonek to thrive.”
The federal agency based its decision largely on the facility’s ability to accommodate his social and medical needs, support all necessary transport and contribute to scientific research on the species to help conservation efforts in the wild.
“We are proud to play our part in Tyonek’s continued care, alongside the federal government and others who have helped since his rescue,” said SeaWorld Chief Zoological Officer Dr. Chris Dold. “Experts from across North America came together to give Tyonek a second chance at life, and this is the culmination of those countless hours of care from passionate and dedicated people.”
NOAA Fisheries determined Tyonek to be non-releasable in January 2018.
According to NOAA Fisheries, at five months, Tyonek is currently nutritionally and socially dependent, and lacks both survival and socialization skills needed to be successful on his own in the wild.
Researchers are using underwater microphones to interpret and characterize the calls of blue whales swimming through Southern California’s oceans, revealing new insights into the behavior of these endangered marine mammals, according to new research being presented at the Ocean Sciences Meeting here on Tuesday.
Stretching nearly 30 meters (100 feet) long and weighing up to 172 metric tons (190 short tons), the endangered blue whale is the largest animal known to have existed. Though the exact purpose of blue whale vocalizations remains elusive, researchers think the whales may use calls to maintain distance between one another, facilitate mating or signal the presence of prey, among other purposes.
To better understand these vocalizations, scientists recorded and analyzed more than 4,500 sounds from blue whales tagged with underwater microphones and pressure sensors in and around Southern California’s Channel Islands between 2002 and 2016. Listen to a recording of two different whale calls here.
The new research compared three types of calling behavior with different diving patterns to uncover behavioral links.
The researchers found some variability in the times and under what conditions whales call or sing. The vocalizations varied depending on the whale’s sex and the dive’s purpose – behaviors with some similarities to other animals, according to Ana Širović, an oceanographer at the Scripps Institution of Oceanography in La Jolla, California, who will present the new findings Tuesday at the 2018 Ocean Sciences Meeting, co-sponsored by the Association for the Sciences of Limnology and Oceanography, The Oceanography Society and the American Geophysical Union.
“Understanding the context under which blue whales make calls is a critical step in developing non-invasive, non-lethal acoustic methods to study population trends and recovery status of this endangered species,” Širović said. “And as a species on top of the food web, understanding their status and contribution to the ecosystem is important for understanding the status of the ecosystem as a whole.”
The researchers found male whales were chattier at night, when it seemed the animals weren’t feeding. Males produce more calls than their female counterparts, Širović said, indicating some of the calls may aid in reproduction.
The researchers noticed great variability in the male whales’ use of single sounds, as opposed to songs composed of multiple sounds strung together. Other researchers have suggested these single calls could help maintain pair-bonding when males and females meet while foraging. Male bonobo chimpanzees employ a similar strategy, calling to nearby females when food is present, which boosts their chances of mating.
The researchers found dive behavior varies with the seasons, when whales spent more time in shallow waters during late summer and early fall. This may mean whales are hunting for more surface-dwelling prey at those times or traveling, according to the researchers.
The rate at which calls are produced varied within the time of day as well, where song production was highest at dusk and lower during the day. This could be because the whales time their singing for periods when prey is less densely aggregated, though the researchers did not measure prey abundance. A similar, energy-conserving behavior has been observed in European robins and nightingales, who adjust their singing in line with their energy reserves.
A shorter, less far-traveling call past researchers had associated only with foraging behavior seemed to be more socially complex than previously thought. Both males and females used this call during non-feeding dives, leading Širović and her colleagues to suggest it may serve as a close-range call to communicate only with nearby whales.
The research represents the most extensive analysis into the behavioral context of blue whale calling in the region, according to Širović.
The travels of whale sharks Tiffany and Doug are causing a stir. As a marine species typically found in tropical waters off Western Australia’s coast, the pair inexplicably have headed south and showed up off the coast of Perth.
Tiffany is an 8m whale shark named after the female pilot who regularly flies scientists over the giants’ favourite haunts near Ningaloo Reef, 1250km north of Perth. Doug is named after a member of the CSIRO Oceans and Atmosphere team conducting a five-year, $5.4 million study of the reef ecology.
The puzzling arrival of Tiffany and Doug so far south is posing questions for scientist Richard Pillans and his team, which attached small transmitter tags to the mottled flanks of 10 whale sharks last year. “Given there are two of our 10 tagged whale sharks in exactly the same place at the same time, it’s very likely there are a lot more sharks out there as well,” he says. “There’s obviously something going on out there.”
As the largest living non-mammalian vertebrate on earth, the whale sharks’ daunting size and gentle habits attract thousands of visitors to the World Heritage-listed Ningaloo Reef each year. Tourists swim alongside the whale sharks in clear Indian Ocean waters.
Perth residents eager to swim alongside Tiffany and Doug would have a hard time even finding them, says Dr Pillans. “Both sharks are in really deep water of 2000m to 3000m on the edge of the continental shelf. That’s really unusual for whale sharks, because more often they stay within 200m of the shoreline.
“Presumably there’s an upwelling of cold, nutrient-rich water that’s being forced up, creating a mass food opportunity like krill, one of their favourite foods.”
Adult females are rarely seen at Ningaloo Reef. “Whale sharks give birth to live young which are less than a metre long, and we know very little about where this occurs,” Dr Pillans said.
The Ningaloo Outlook project, a partnership between CSIRO and BHP, hopes to shed light on such aspects, and on the reef’s complex ecosystem.
“One of the aims is to look at the impact of ocean warming on the distribution of whale sharks on the WA coast, but we haven’t got a good handle on that yet,” said Dr Pillans. “None of the previous tagged sharks have come this far south.”
That Tiffany and Doug were found 130km off Perth’s coastline may be unusual, but another tagged whale shark, Roger, made a longer journey, from Ningaloo to Queensland’s Gulf of Carpentaria, about 3500km away.
Last year a tagged animal made it to Christmas Island, 1500km northwest of Ningaloo.
“One of the hard things with whale sharks is to keep the tags on them for long enough to get meaningful data,” said Dr Pillans. “Nine to 12 months is basically what we’re aiming for in order to track them as they move away from Ningaloo.”
Whether Tiffany and Doug’s travels are motivated by food or sexual frolic is unknown.
WASHINGTON — Some of the nation’s leading coral scientists stressed Thursday that the situation facing coral reefs is nothing short of desperate — and a drastic cut in global carbon dioxide emissions won’t be enough to protect corals from deadly bleaching events and other environmental threats.
In hopes of giving the reefs a fighting chance, a newly formed committee of the National Academies of Sciences, Engineering and Medicine will review a variety of potential intervention strategies, from genetic modification of coral species to spraying salt water into the atmosphere to shade and cool reefs.
At the committee’s first meeting on Thursday, Mark Eakin, coordinator of the National Atmospheric and Oceanic Administration’s (NOAA) Coral Reef Watch, said the “severity” of what has occurred between June 2014 and May 2017 — the “longest, most widespread, and possibly the most damaging” bleaching event on record — has changed the scientific community’s perspective about what should be done.
“The dire situation is here now,” he told the 12-person committee at its first meeting on Thursday. “We know that climate change is accelerating and accelerating bleaching. And so we need to make sure that this study isn’t something that talks about some nice areas of science but is too little and too late for the corals.”
The project, titled “Interventions to Increase the Resilience of Coral Reefs,” is expected to take up to two years and will assess both the risks and benefits of intervention strategies. It is sponsored by NOAA.
Tom Moore, manager of NOAA’s Coral Reef Restoration Program, said the agency’s position is that saving the world’s reefs will require a multi-pronged approach that includes “immediate and aggressive action” to combat climate change, ongoing restoration and more drastic measures.
“We are trying to buy time here until hopefully we get things in check on a global scale,” he said.
Although still hopeful, Moore and others are realistic about the challenges ahead. They stressed that the enormity of the problem and a lack of resources means the scientific community will face tough decisions.
A recent United Nations-backed study found that “annual severe bleaching” will impact 99 percent of the world’s reefs within the century if humans do not take swift action to curb greenhouse gas emissions.
“Tomorrow’s reefs are not going to look like yesterday’s reefs,” Moore said.
The most sobering appeal came from Joanna Walczak, a regional administrator at the Florida Department of Environmental Protection. Over the last three years, she says she helplessly watched the majority of the reef-building corals off Florida’s southeast coast collapse due to an unknown disease outbreak.
“I’ve gone through many, many different stages of grief, from visceral sadness to disbelief and anger. I’ve definitely had some despondence and actually was planning for a career change because I really, truly didn’t see hope for a while there,” she told the committee via a video feed. “But I’ve ultimately come through all of that and have made it back with focus and determined action to do everything in my power to make a difference with whatever little time we have left.”
Florida is already out of time, Walczak added. And with the rate that corals are currently being lost, officials there have had to completely shift their management strategy, from reactive to proactive. Among the ideas being entertained are large-scale disease treatment on the largest coral colonies and culling, which Walczak said means “specifically sacrificing some to potentially save the rest.”
“I’m going to make a really hard ask of you all,” she told the committee. “I need precautionary principle-based, expert-opinion-derived leaps of faith. Because after all I’ve seen, I’m ready to take these risks now.”
The study by the National Academies kicks off as the Trump administration abandons the Obama administration’s efforts to combat climate change and works feverishly to promote fossil fuel production in its quest for “energy dominance.” President Donald Trump — who famously dismissed climate change as a Chinese hoax in 2012 — has surrounded himself with like-minded climate change skeptics, including Environmental Protection Agency Administrator Scott Pruitt, who this week suggested global warming may be beneficial to humans.
BREATHTAKING scenes of a seal working with dolphins to feast on fish have been captured by an ingenious underwater camera.
The mother fur seal filmed herself feasting on a giant “bait ball” of anchovies from a tiny lens fitted to her back by a wildlife television crew.
These remarkable scenes of the seal powering through the swirling mass of small fish corralled by a school of dolphins have given scientists a unique insight into the marine mammals they have been studying for more than 20 years.
In just two hours, Gordon Buchanan’s Animals with Camera team not only came up with gripping scenes from the shark-infested waters off Australia’s Kanowna Island, their footage has explained some of the holy grail mysteries of how fur seals survive in such a harsh marine environment.
By fitting a tiny waterproof camera to one of the island colony’s 15,000 seals, scientists have discovered how they evade the attentions of marauding great white sharks as well as the way they eat a wide array of prey and even team up with dolphins for spectacular feasts.
Professor John Arnould from Melbourne’s Deakin University was left awestruck as the camera relayed crystal clear shots of the mother’s seal hunting forays back to shore.
Footage first shows how she clambers from the nursery colony over rocks into the sea and then takes a seaweed manicure to remove parasites off her luxuriant fur.
Then, she gets down to the business of hunting, ever alert to the huge great white sharks that patrol the waters on the look out for their favourite food – fur seals.
The mother seal is filmed hugging the sea bed as this prevents her being attacked from below, one of the favourite ambush techniques of great whites.
Although the seal has to surface to breath every eight minutes, she performs a series of barrel rolls so she can spot any sinister shark in the vicinity.
While her own hunting strategy sees her capturing a cuttle fish and octopus, it the sight of a dolphin pod creating the anchovy bait ball that leaves Professor Arnould almost nonplussed.
He says: “I’ve learnt so much from the camera footage that it’s hard to know where to start.
“We’ve discovered they eat a lot more of some prey types than we previously thought and some prey we didn’t know they consumed.
“And we’re beginning to understand just how much time and effort these animals devote to vigilance and predator avoidance.”