Tag Archives: whales

Whales eat much more than we assumed, and it has huge ecological implications

Baleen whales eat a lot more food than previously assumed: three times as much, to be exact, according to new research. The findings are not meant to shame these animals into going on a diet. Rather, they shed light on the key ecological role whales play in the ocean.

Image via Pixabay.

The sheer size and appetite of whales make them important players in the ocean. In particular, they serve as key drivers of nutrient recycling in the ocean. They consume vast amounts of food, releasing important nutrients back into the water following digestion. A new paper refines our understanding of just how much food whales as a group can consume, and take a look at the ecological implications of the decline in whale numbers since the onset of the 20th century.

Big eaters

“While it may just seem like a fun trivia fact, knowing how much whales eat is an important aspect of ecosystem function and management,” Matthew Scott Savoca, a Postdoctoral Research Fellow at Stanford University and corresponding author of the paper, told ZME Science. “If we want to protect whales and make sure they are thriving in modern oceans, then knowing how much food they need to survive and reproduce is critical.”

“There are implicit benefits of having whales on the planet — isn’t it cool to think that we live at a time when we’re alongside the largest animal in the history of life on Earth? Beyond that, whales have direct value as carbon sinks (e.g., sequestering carbon in their bodies and exporting it to the deep sea when they die and sink – which we did not discuss in this study). In addition, whale watching is a multi-billion dollar per year global business that is expanding as whales are recovering.”

Previous estimates of just how much whales eat were built upon data obtained from metabolic models or direct analysis of the stomach contents of whale carcasses. Such data can give us a ballpark figure but, according to the new paper, they are quite inaccurate.

Savoca and his colleagues directly measured the feeding rates of 321 baleen whales across seven species in the Atlantic, Pacific, and Southern oceans. They tracked foraging behavior and estimated prey consumption by tracking the whales using GPS tags. Location data was then combined with sonar measurements of prey density, of the quantity of prey consumed per feeding, and current estimates of how much each species typically eats per feeding event.

Overall, the results suggest that we’ve underestimated how much food baleen whales ingest by a factor of three. On average, these animals consume between 5% and 30% of their body weight per day, depending on species, across all the investigated regions. In total, blue, fin, and humpback whales in the California Current Ecosystem consume over two million tonnes of krill every year per species.

The study also puts into perspective just how massive an impact whaling and other stressors have placed on whales and, by extension, on the ecosystems they inhabit. Prior to the 20th century, the team estimates, whales in the Southern Ocean were consuming around 430 million tonnes of Antarctic krill per year. This figure is twice the total estimated biomass of Antarctic krill today.

Whales, the paper explains, serve an important ecological role as nutrient recyclers, tying into that last tidbit of information. Prior to the 20th century, before whales were hunted in meaningful numbers, these animals consumed a massive amount of biomass, releasing much of the nutrients in their food back into the ocean as waste. This, in turn, allowed for much greater productivity in the ocean (as they made large quantities of nutrients freely-available for krill and other phytoplankton to consume).

“In brief, if whales eat more than we thought, then they also recycle more nutrients (i.e., poop) than we thought. If that is the case then limiting nutrients may have been used more effectively and efficiently in a system that had many more whales,” Savoca said for ZME Science. “It’s not that these whales add more iron (or other nutrients) to the system, they just [move] it from within the bodies of their prey, to in the seawater itself where it could, in theory, fertilize phytoplankton — the base of all open ocean food webs.”

To put things into perspective, the authors estimate that today, baleen whales in the Southern Ocean recycle around 1,200 tons of iron per year; prior to the 20th century, this figure was likely around 12,000 tons of iron per year. In essence, whaling has led to a 90% decrease in the amount of essential nutrients whales can recycle in their ecosystems.

I asked Savoca whether there is any overlap between the decline in baleen whale populations and the detrimental effects of industrial fishing on today’s ocean ecosystems. Should we expect trouble ahead as we’re removing key nutrient recyclers from one side of the equation, and taking more fish out of the sea on the other?

“You are hitting on a major issue,” he admitted. “We have noticed that oceans have become less productive after removing millions of large whales in the 19th and 20th centuries. The same is true of ongoing industrial fishing. The collapse of predatory fish communities have the same detrimental impacts on marine communities as the wholesale decimation of the whales did.”

“I am not against fishing, but we have to do so as sustainably as possible if we want to maintain essential ocean productivity into the future.”

Whales and their extended family — cetaceans — have been experiencing immense pressures ever since the onset of industrial-scale whaling in the early 20th century. Commercial whaling only slowed down in the 1970s, which is a very, very short time ago from an ecological perspective. This has allowed whales and other cetaceans some much-needed respite, but they are still struggling. Over half of all known cetacean species today are inching towards extinction, 13 of which are listed as “Near Threatened”, “Vulnerable”, “Endangered”, or “Critically Endangered” on the International Union for Conservation of Nature’s (IUCN) Red List of Threatened Species. Besides the lingering effects of whaling, this family is still struggling under the combined effects of (chemical and noise) pollution, loss of habitat, loss of prey, climate change, and direct collisions with ships.

Research such as this study and many others before it can raise an alarm that not all is well with the whales. But actually doing something about it hinges on us and governments the world over taking the initiative to protect them. Understanding just how important whales are for the health of our oceans and, through that, for our own well-being and prosperity definitely goes a long way towards spurring us into action.

But Savoca’s conclusion to our email discussion left an impression on me. There is great beauty in natural ecosystems that we’re destroying, oftentimes unaware. Beyond the practical implications of conserving whale species, we have a chance to conserve these for our children and all future generations.

“I remember one day in Monterey Bay when we were surrounded by blue whales (likely over a dozen), each about twice the size of the boat we were on. I will also never forget the sound and scale of the ice in Antarctica,” Savoca wrote for ZME Science.

“My life’s work is devoted to making sure people and animals have these (and ideally ever better) ecosystems of awe and plenty well into the future.”

The paper “Baleen whale prey consumption based on high-resolution foraging measurements” has been published in the journal Nature.

Fossil Friday: ancient whale that walked on all fours found deep in the Egyptian desert

Roughly one decade ago, Egyptian environmentalists uncovered the bones of an ancient whale — in the sands of the Western Desert. Now, a new paper details this strange finding, describing a brand new species of ‘semi-aquatic’ whale ancestor.

The holotype (the specimen from which the species was described and named) of Phiomicetus anubis. Image credits Abdullah S. Gohan et al., (2021), Proc. R. Soc. B.

This four-legged whale ancestor lived around 43 million years ago, and was, by all indications, an accomplished hunter.

Grandma whale

“We chose the name Anubis because it had a strong and deadly bite,” said paleontologist Hesham Sallam, professor of paleontology at Mansoura University in Egypt, who led the research effort. “It could kill any creature it crossed paths with.”

Phiomicetus anubis is a key new whale species, and a critical discovery for Egyptian and African palaeontology,” the study’s lead author, Abdullah Gohar, told Reuters news agency.

The whale is part of the extinct Phiomicetus genus of protocetidae whales — essentially, the family from which modern whales emerged. It was given the name Anubis in honor of the ancient Egyptian god of death, as judging from its fossils, the animal was quite an accomplished killer.

The animal’s elongated snout and skull point to it being a capable carnivore both in regards to grasping prey and chewing through tough hides and bones.

Perhaps its most unusual features, for most people, would be that P. anubis was semi-aquatic, and possessed four stout legs instead of flippers. The area that makes up the Western Desert today used to be a sea 43 million years ago. P. anubis hunted in its waters and, likely, walked around its shores.

The fossil was first found in 2008, but Sallam put off investigating it until 2017, as he worked to assemble a team of paleontologists that would do the fossil justice. Their work culminated last month when they officially confirmed that the fossil belongs to a completely new species.

From a paleontological standpoint, the discovery is particularly exciting as P. Anubis is one of the last known members of the whale family that retained functional, land-going limbs. Whales as a family have evolved from land mammals that returned to the sea, also transitioning from a herbivorous to a carnivorous diet in the process. Today, all members of the whale family (cetaceans) live exclusively in the seas and oceans. Thus, they have quite an interesting story to tell.

P. anubis was a species that emerged during that transition period, making it a valuable source of information on how it took place and when. Fossils from this window of the whales’ evolutionary history are particularly valuable for helping us understand when they finally made the full transition to ocean life, and where. Currently, our best indication is that it took place around 50 million years ago in today’s India or Pakistan, but this is by no means a settled topic. The new species will undoubtedly help flesh out our understanding of this timeline.

Surprisingly for a desert, Egypt’s Western Desert is quite famous for its prehistoric whale fossils. One area in particular, the White Valley of Wadi al-Hitan, has been declared a natural World Heritage site and attracts a lot of tourist attention due to its prehistoric whale fossils.

The paper “A new protocetid whale offers clues to biogeography and feeding ecology in early cetacean evolution” has been published in the journal Proceedings of the Royal Society B: Biological Sciences.

Swallowed whole: lobster diver swallowed and spat out by humpback whale

Humpback whales are gentle giants who don’t enjoy interacting with humans — but it’s still advisable to keep a distance from them. Image credits: Flicker Photos.

Michael Packard has been a lobster diver out of Provincetown for 40 years, but he wasn’t prepared for what was about to happen.

“All of a sudden, I felt this huge shove and the next thing I knew it was completely black,” Packard recalled Friday afternoon following his release from Cape Cod Hospital in Hyannis. “I could sense I was moving, and I could feel the whale squeezing with the muscles in his mouth.”

Packard’s vessel, the “Ja’n J,” was surrounded by a fleet of boats catching striped bass. He went diving when, without warning, he felt scooped up. Although he didn’t feel any injuries or teeth, he realized he had been swallowed and things were pretty bad.

“Then I felt around, and I realized there was no teeth and I had felt, really, no great pain,” he said. “And then I realized, ‘Oh my God, I’m in a whale’s mouth. I’m in a whale’s mouth, and he’s trying to swallow me.’ “

“I was completely inside; it was completely black,” Packard said. “I thought to myself, ‘there’s no way I’m getting out of here. I’m done, I’m dead.’ All I could think of was my boys — they’re 12 and 15 years old.”

Still in his scuba gear, Packard started moving and struggling, until the whale began shaking its head. Packard felt the whale didn’t like, and after 30 seconds that seemed like an eternity, the whale finally surfaced and spat him out.

“I saw Mike come flying out of the water, feet first with his flippers on, and land back in the water,” Joe Francis, a charter boat captain who happened to be nearby, told WBZ-TV. “I jumped aboard the boat. We got him up, got his tank off. Got him on the deck and calmed him down and he goes, ‘Joe, I was in the mouth of a whale.’ “

“Then all of a sudden he went up to the surface and just erupted and started shaking his head. I just got thrown in the air and landed in the water,” Packard recalled. “I was free and I just floated there. I couldn’t believe. . . I’m here to tell it.”

Packard’s story was corroborated by his own crew, as well as Francis, and experts say that while extremely rare, this type of accident can happen. The whale doesn’t want to swallow people, but it can do so out of carelessness — much like a cyclist swallowing a fly. When a humpback whale opens its mouth to feed, it billows out and blocks its forward vision. This helps the whale scoop up more prey, but also makes it unable to distinguish what it’s scooping up.

Unlike toothed whales such as orcas, baleen whales such as the humpbacks cannot injure humans with their teeth; their esophagus is also too small to actually swallow a human. But whales can still cause a lot of damage to the unfortunate creatures they swallow. “He’s damn lucky to be alive,” Captain Joe Francis added.

Even so, what Packard went through is extremely rare. Whales don’t generally want to interact with humans, and it’s not uncommon for divers in the tropics to swim alongside them, enjoying a lovely experience. Experts generally advise keeping a distance of around 100 meters to avoid any potential accident.

Packard was released from Cape Cod Hospital Friday afternoon. He described his injuries as “a lot of soft tissue damage” but no broken bones. He said he’d return to diving as soon as he was healed.

Operation Beluga — or how a Soviet ice breaker played music to whales to save them from starving

The Soviet Union (USSR) is a thing most people today know only from memory or history books. And many parts of its history are unsavory, to say the least. But Operation Beluga (‘Belukha’ in Russian) isn’t one of those. Operation Beluga involved them sending an ice-breaker, and blasting classical music at full volume, in order to save a pack of thousands of whales that were iced-in in the Chukchi Peninsula.

A beluga whale at the Oceanografic de Valencia, Spain. Image credits Salva Barbera via Flickr.

In 1959, the Finish company Wärtsilä delivered the ice-breaker Moskva to the USSR. The contract for this ship was signed three years prior, and as part of its stipulations, the ship was equipped with one of the most powerful diesel-electric engines at the time. It would go on to help hundreds of ships navigate the (iced-over) Northern Sea Route, which spans from Murmansk to Vladivostok, cutting the travel time down to an average of 10 days — which was quite fast for the day. Moskva’s powerful engines allowed it to break through thicker ice than its peers at the time, which effectively extended the shipping season possible along this route.

Crowned with shipping glory, the Moskva was later stationed in Vladivostok and sent to escort ships along the eastern stretches of the Northern Sea Route. But as fate would have it, this would not be the last time we heard of the Moskva’s adventures — ‘we’ here meaning us, as well as beluga whales.

Iced in, iced out

Every good heroic story needs someone in need, and in around December 1984, thousands of such someones were found.

Along the frigid landscape of the Chukchi Peninsula (this is the bit of Russia that’s across the pond from Alaska) lives the Chukchi or Chukchee, an indigenous people closely related to the original inhabitants of the Americas. Their traditions and lifestyle hadn’t changed much until 1920 when the Soviet government organized (state-run) schools and industries in the area. Even after this point the Chukchi relied heavily on local wildlife for food and provided raw materials for some of those newly-minted industries in the form of fishing, hunting of marine mammals, or reindeer herding. Subsistence hunting (i.e. for the purpose of obtaining food) is still practiced by the Chukchi to this day, although it’s greatly reduced in scope.

In late December 1984, a Chukchi hunter or hunting party — it’s not known exactly how many people were present at that point — happened upon the motherlode of prey: roughly 3,000 beluga whales trapped in the frozen waters of the peninsula’s Senyavin Strait. The hunter realized they were trapped because the whales (a prime local source of food) were flocking around small pools of open water dotting the strait, desperate to catch a breath of air.

Faced with such a sight, those present were likely very excited at the prospect of easily-captured meat. As they inched closer, however, the magnitude of what they were actually seeing started to sink in: the straight hold around 3,000 whales.

To this day, we’re still not sure how they got there, especially in such huge numbers. One running theory is that the whales — either as a whole or as several smaller groups — chased after prey, most likely a bank of cod, right into the straight. Powerful winds then filled the straight with chunks of drift ice up to 12 ft (4 meters) thick. This was way too strong for the whales to break through, leaving only small openings between the chunks of ice for the whales to breathe through. Now, the whales could swim under this ice to freedom, but the distance was too long for them to make the trip on a single breath of air — which was a risky endeavor. So, they stayed put.

Needless to say, finding thousands of whales stranded in a straight is the kind of thing you tend to report to authorities, which the hunter did. Experts and helicopters were dispatched to survey the scene, and locals even brought frozen fish to feed the trapped whales.

Enter the Moskva

The Moskva, photographed while being built in dry dock. Image via Wikimedia.

The teams sent to the site quickly concluded that the only way to save the whales was to clear a path through the ice for them to escape. Four-meter-thick ice is hardly a trivial barrier, and due to this (alongside the close proximity of Vladivostok), the Moskva was eventually sent to break the whales free.

According to Whalescientists, when the Moskva first reached the area (in February 1985), its captain A. Kovalenko, whose full first name I’ve been unable to find, wanted to call the mission off. The ice was simply too thick. He seems to have changed his mind “after dozens of whales started to perish”. However, there are also some reports of up to 500 whales being carried off by local hunters; whether these were hunted or taken after their deaths, we don’t know. But Whalescientists adds that the helicopters were used to feed the whales during this time. So, there were genuine efforts to keep these animals alive being made at this time, despite the obvious conflict of interests between a community that practices subsistence hunting to this day, and a big, trapped pack of animals.

Still, after this initial delay, the crew weighed down the ship with as much fuel as it could carry, and forced it through the ice. At first, however, it didn’t go quite the way they expected.

The whales seemed very excited for the new space made available to them, going out through the large gaps in the ice to feed and rest. They were happy to be out of the water and recovering, even “playing, whistling, squealing, snorting” according to a Russian state newspaper cited by The New York Times.

But they didn’t come close to the ship or the passage it was clearing. The icebreaker moved “to and from the herd”, making no progress — then “someone” recalled that beluga whales reacted well to music. So they turned up the speakers on the Moskva’s deck and tried it, discovering that classical music seemed to attract the whales. It was a Pied Piper moment.

In the end, the crew made repeated forays through the ice, going back and forth towards the whales, to make them understand. The animals eventually started following them “kilometer by kilometer” on the passage the ship created. In this way, the many trapped whales (around 2,000) finally found their way to freedom.

A whale of a time

Now, not everyone reading this has had the ‘pleasure’ of living under totalitarian regimes, as the USSR was. Given that our primary sources for these events were state-controlled — as virtually all official news outlets were — and that states have a vested interest in painting themselves as kind, generous, just, and therefore legitimize themselves, we can assume that certain elements of the story were done up a bit, or that other unsavory details never made it in the published story. So don’t take everything here at face value.

But overall, Operation Beluga definitely happened. It’s a very heartwarming story of how humanity can foster and protect our cousins in the wild. It also showcases how behaviors that evolve over thousands of years can serve a species in general but fail them in particular situations they simply weren’t designed to deal with. In such conditions, our technology and ability to think on our feet can help solve the issue.

I personally enjoy thinking that humanity will, one day, take on the role of fostering the natural world around us. Stories like this one show how all of us stand to benefit: we get aww-inducing feel-good stories, feelings of fulfillment, and healthy ecosystems. The whales get to not starve to death. Definitely a win-win.

Breathtaking underwater photographs document the hidden lives of humpback whales

Humpback whales (Megaptera novaeangliae) are some of the most charismatic creatures of the world, thanks to their frequent aerial acrobatic displays and elaborate songs. Every year, these gentle giants migrate from their summer feeding grounds to their winter breeding grounds, and some people are blessed enough to cross paths with them.

Sydney-based photographer Jem Cresswell spent so much time submerged in the southern Pacific Ocean with these humpback whales, he could have easily passed as one of their calves.

For four years between 2014 and 2018, Cresswell took countless shots of humpbacks and their calves off the coast of Tonga, capturing the majestic marine creatures in never-before-seen intimate poses. His incursions into the secret lives of humpbacks have been documented in a 220-page photo book called Giants — and the author has been gracious enough to share some of the book’s material in this article.

“I grew up exploring the rugged desolate coastline of The Great Australian Bight, surfing, diving, and camping with friends. This sense of escape and freedom grew my love of the ocean.

Below the surface it feels like you’re entering another world, it’s such a multi-sensory experience and there is always something new to see. I initially found it quite intimidating, but now I am in awe of what lives below,” Cresswell told ZME Science.

“I now live on the east coast of Australia where every year numerous whales travel past on migration to the warmer breeding grounds of the pacific. I was initially drawn to humpback whales due to their gentle nature, sheer size, and the feeling of insignificance in their presence. I began this project with the aim of creating portrait images of the humpback whale with eye contact with the camera, on lenses that I would normally use in the studio to photograph the portrait of a human. I wanted to try and capture the expressive emotions and individual personalities of these gentle giants.”

“There is very little you can control underwater, except for the technical side of your camera and your body language. You are at the mercy of the elements, and of the wildlife, which makes it all the more rewarding when everything comes together. The biggest challenge was the pure amount of time out on the water. To have the opportunity to capture the portrait style images I envisioned required a genuinely curious whale to come over to investigate you, which is where the moments of eye contact and interaction were evident. Every encounter with a humpback whale is unique. The possibility of what you might capture is endless, especially when you let these incredible creatures dictate the terms of the interaction,” Cresswell said.

“One of my most memorable moments was with a mother humpback and her young calf. After watching them for a long time, we entered the water from a distance, just floating silently, observing and keeping our heart rate down. After about 15 minutes, we edged closer in short increments, watching their behaviour. Initially mum kept an eye on us, but before long she was closing it, completely relaxed, resting below the surface,” Creswell recounted.

“The small calf was atop mum’s head, using its pectoral fins to hold on. Every so often mum would gently lift the calf to the surface to breathe. The calf would then swim underneath its mother and feed, before taking its place back atop her head. After a while, the calf closed its eyes and rested. The bond between the mother whale and her calf was undeniable and it was a beautiful exchange to witness first hand.”

“Over the following weeks, we swam with the same mum and calf on several occasions. It was amazing to see how much the calf had grown and the confidence she had developed. It’s experiences like this that will always draw me to nature and have taught me a greater appreciation for all life on this planet.”

Humpbacks are famous for their exuberant and haunting songs. These complex, lengthy, and distinctive songs are relayed by males to communicate their presence to females and entice them to mate. These sounds range from canary-like chirps to deep rumblings sounds that can be sensed from hundreds of kilometers away. Each humpback population has different songs, and every year the songs change subtly.

“One of the things that fascinate me is that only the male humpbacks sing the complex songs. All of the male humpbacks migrating to the same breeding ground sing the same song, though it may evolve over time. Every few years the song is retired, and a completely new song is created. A study of whale song over a 19-year period has shown that whilst there can be some general patterns, the exact combination of sounds are never repeated. I have been in the water near a male humpback singing, and it was so loud it was causing my whole body to vibrate on the deeper tones,” Cresswell said.

Humpback whales were nearly hunted to extinction once. A 1985 ban on commercial whaling has since helped some populations rebound, although their numbers haven’t nearly recovered to their historical highs. Today, the biggest threats to humpbacks are collisions with ships and entanglement in fishing gear.

“It is amazing to be witnessing the humpback whale numbers slowly recovering, especially after an estimated 200,000 humpback whales were butchered between 1904 and 1980, seeing the global population reduced by 90%. There so much more to be learned from these intelligent and complex creatures. They are worth so much more alive,” Cresswell said.

Cresswell is currently working on a project celebrating the beauty of a particular species found on Australia’s Great Barrier Reef. This project will have an exhibition series, as well as a large video and sound installation, to help people immerse themselves in the experience, the artist told ZME Science.

You can learn more about Jem Cresswell’s projects and buy Giants on his website. Follow Jem on Instagram for more breathtaking underwater photography.

All the photos in this article have been shared with permission from Jem Cresswell. For those curious, he used a Canon 5DS R, 24-70mm F2.8L II and 16-35mm F4L in an Aquatech underwater housing.

Whales enjoying the sound of silence as COVID-19 pandemic reduces ship traffic

Whales and other sealife have experienced a dramatic decrease in noise pollution this year. (Image: Pixabay)

COVID-19 might be terrifying the rest of the world, but the whales sure are probably enjoying it. Declines in the economy due to the coronavirus have slowed exports and imports by around 20 percent and this has caused a dramatic decrease in the ocean noise.

Oceanographer David Barclay of Canada’s Dalhousie University and his team have been analyzing ocean sound signals from seabed observatories run by Ocean Networks Canada near the port of Vancouver. Their observations of sound power in the 100 Hz range from two sites have revealed a decrease in noise level of up to five decibels.

“There has been a consistent drop in noise since January 1, which has amounted to a change of four or five decibels in the period up to April 1,” Barclay told The Guardian. “Generally, we know underwater noise at this frequency has effects on marine mammals.”

The two research locations include a deep-ocean site approximately 60 kilometers (37 miles) from the Vancouver port in 3,000 meters (9,842 feet) of water and a more shallow inland site. The deepwater location recorded a drop in weekly noise of 1.5 decibels.

A study of baleen whales after the 9/11 attacks in 2001 showed that the reduction in ship and air traffic was associated with a reduction in chronic stress in marine mammals.

“We are facing a moment of truth,” Michelle Fournet, a marine acoustician at Cornell University, who studies humpback whales in southeast Alaska, told The Guardian. “We have an opportunity to listen – and that opportunity to listen will not appear again in our lifetime. “

“We have a generation of humpbacks that have never known a quiet ocean,” said Fournet.

The drop in tourism has also been a source of the decline of ocean traffic, another added benefit for cetaceans. Late April generally marks the beginning of the cruise ship season in southeast Alaska with boats docking in Vancouver before heading to the 49th state.

“What we know about whales in southeast Alaska is that when it gets noisy they call less, and when boats go by they call less,” said Fournet. “I expect what we might see is an opportunity for whales to have more conversation and to have more complex conversation.”

“The clearest benefit of the reduction in vessel traffic is to humpback mothers and nursing calves, who tend to be somewhat reclusive,” Marc Lammers, research coordinator for the Hawaiian Islands Humpback Whale National Marine Sanctuary, told Hawaii’s Star-Advertiser. “Not having humans either trying to view them or, in some cases, interact with them will be a huge benefit for the mother, whose priority is to protect and nurse her calf so it can be strong enough to make the trip to Alaska. It allows her to conserve her energy and transfer that energy to her calf in peace, without having to respond to stand-up paddlers and five or six boats approaching at a time.”

Whales blow bubbly nets to help them fish — and we have it on camera

New research at the University of Hawaiʻi at Mānoa is shedding light on whales’ bubble-net fishing.

Cetaceans, the group that whales and dolphins are part of, are pretty smart creatures. We’ve known that they can use ‘nets’ to catch food — the animals dive deep and swim in a circle around their prey, blowing out bubbles as they do. The rising body of air traps fish in the middle. Other whales then simply have to swim up with their mouths open and cash in on the food with virtually zero effort.

Now, new research is showing what this process looks like from the perspective of the whales.

Like shooting fish in a barrel

“We have two angles. The drone’s perspective is showing us these bubble nets and how the bubbles are starting to come to the surface and how the animals come up through the bubble net as they surface, while the cameras on the whales are showing us the animal’s perspective,” said marine biologist Lars Bejder of the university’s Marine Mammal Research Program.

The study included members from the Alaska Whale Foundation, members of Stanford University’s Goldbogen Lab, and from the Bio-telemetry and Behavioral Ecology Lab at the University of California, Santa Cruz. Together with Bejder and colleagues at UH Mānoa, they stuck cameras and accelerometers on whales using suction cups. The material was supplemented by drone footage of the behavior from above to create an “exciting” set of data, Bejder explains.

Migratory humpback whales spend their summer along Alaska’s coast before heading down to Hawaii for winter — where they’ll raise a new generation of whales. However, all that romance leaves little time for feeding (the humpbacks eat very little during their breeding period), so fat reserves need to be plumped up before the journey.

That’s where the bubble nets come into play. Whales could just swim around and filter krill the old fashioned way, but time is of the essence during winter. The bubble-fishing technique allows groups of whales to invest as little time and energy as possible while maximizing their caloric intake. It’s a win-win approach.

The team notes that the behavior is learned — the whales don’t instinctively engage in bubble fishing. Not all humpbacks hunt this way, they add, and there is a pretty wide range of variations in technique among those who do. However, it’s always a cooperative process, requiring groups of whales to work together to ensure that everyone has a chance at the buffet.

The team reports that the behavior has also been observed Bryde’s whales (Balaenoptera edeni) and bottlenose dolphins (genus Tursiops) off the coast of Florida. Instead of using bubbles, however, these groups of cetaceans engage in mud-ring feeding: this involves stirring up a ring of sediment in shallow waters to trap schools of fish.

This study was done in an effort to understand just what is going on with humpback whales. A ban on commercial whaling in 1985 saved the species from almost assured extinction and, while they have recovered somewhat, there has been a substantial decline in humpback whale sightings over the last five years, the researchers report. Some of the factors they are considering include changes to food populations, anthropogenic impacts on their habitat, and climate breakdown.

But, while the researchers ply their trade, we’re left with some awesome shots of whales doing whale things — of course no one’s complaining.

“The footage is rather groundbreaking,” Bejder said. “We’re observing how these animals are manipulating their prey and preparing the prey for capture. It is allowing us to gain new insights that we really haven’t been able to do before.”


Roman fish salting workshops reveal two whale species lost from the Mediterranean

The Roman Empire used to dine on whale fished from the Mediterranean Sea — the two species have, since then, virtually disappeared from the area and the wider North Atlantic, however.

Grey whale.

Adult grey whale.
Image credits José Eugenio Gómez Rodríguez.

Bones discovered in the ruins of a Roman fish salting compound near the strait of Gibraltar suggest that the Empire’s subjects may have hunted whales for food. The implications are interesting not only from a historical and archaeological point of view — the Romans are not traditionally regarded as accomplished sailors — but also from an ecological standpoint.

Bread, games, and salted whale

Back in Rome’s heyday, the Gibraltar region served as a central fish-processing hub. Ruins from hundreds of factories outfitted with large salting tanks (indicative of an industrial-scale endeavor) still litter the area. Based on the scale of the industry, it’s likely that the products manufactured here used to reach far and wide onto plates across the Roman Empire.

The recent discovery of whale bones amid these workshops in the Gibraltar region stands to change our understanding of the Roman fishing industry and the history of two whale species — which have now virtually disappeared from the North Atlantic area.

One team, led by researchers from the Archaeology Department at the University of York, drew on DNA analysis and collagen fingerprinting to identify the bones — their results showing the remains belonged to the North Atlantic right whale (Eubalaena glacialis) and the Atlantic gray whale (Eschrichtius robustus).

The findings surprised them, to say the least. On the one hand, the Mediterranean, despite housing several species of whales and other cetaceans today, was always considered outside of the historical range of both the gray and right whale. On the other hand, the Romans simply didn’t have the means to fish such large prey — none that we’re aware of, anyway.


Some fish-salting tanks in the ancient Roman city of Baelo Claudia (near today’s Tarifa in Spain). The largest circular tank is 3 meters / 10 feet wide, with some 18 meters3 / 193 cubic feet capacity. They were used to salt large fish such as tuna, but perhaps whales as well.

Right whales are listed as Endangered under the IUCN’s Red List, and are further protected by the Endangered Species Act in the US. The species is considered to be one of the hardest-pressed species of whales in the world. Populations in the western North Atlantic can only boast a few hundred individuals, while those in the eastern North Atlantic may already be functionally extinct, with under 50 members.

Gray whales technically fare much better and are listed under ‘least concern’ overall, as there are enough individuals to ensure a stable population and the last three years have seen an increase in their numbers. The western subpopulation is listed separately — based on genetic evidence showing they’re an isolated, distinct group — as ‘Critically Endangered.’ However, it must be noted that the gray whale has been completely wiped out in the North Atlantic, and the family’s range is now limited to the North Pacific exclusively.

Both species got so ragged after centuries of whaling. For context, the first records of right whale hunting come from Basque (northern Spain) whalers plying their trade in the Bay of Biscay in the 11th century. Gray whales have been hunted by indigenous populations since antiquity, although it’s likely that right whales suffered a similar fate.

Previously widespread

The findings, however, suggest that both species once inhabited much wider ranges than we ever suspected. The findings were only made possible by their use of “new molecular methods” to analyze the whale bones, the team says.

“Whales are often neglected in Archaeological studies,” says Dr. Camilla Speller, paper co-author, “because their bones are frequently too fragmented to be identifiable by their shape.”

“Our study shows that these two species were once part of the Mediterranean marine ecosystem and probably used the sheltered basin as a calving ground.”

Since both species are migratory, their presence east of Gibraltar (the strait that connects the Mediterranean sea to the Atlantic) suggests they came here to give birth in safer waters.

Southern Right Whale.

Southern Right Whale (Eubalaena australis).
Image credits Gregory “Slobirdr” Smith / Flickr.

The findings also raise the possibility that the Romans developed a form of whaling alongside traditional fishing practices. However, the evidence is far from conclusive. There is evidence that they fished for large species such as tuna, but based on what we know of their sailing and boat-building capabilities, it seems rather unlikely they would be able to hunt something as large as a whale.

“[…] perhaps the bones are evidence of opportunistic scavenging from beached whales along the coast line,” adds Dr. Speller.

“Romans did not have the necessary technology to capture the types of large whales currently found in the Mediterranean, which are high-seas species. But right and gray whales and their calves would have come very close to shore, making them tempting targets for local fishermen,” says study lead author Dr. Ana Rodrigues.

The opportunistic approach is more likely, especially since we know Basque whalers centuries later would successfully hunt for their prey using small rowing boats and hand harpoons.

The findings also help clarify historic sources such as texts penned by Roman naturalist Pliny the Elder, which describes killer whales attacking newborn calves and their mothers in the Cadiz bay. Today, such descriptions simply don’t make any sense, “but it fits perfectly with the ecology if right and gray whales used to be present,” according to co-author Anne Charpentier, a lecturer at the University of Montpellier.

The authors hope that — armed with their findings that coastal whales once formed an important part of the Mediterranean ecosystem — historians and archeologists can make better sense of other primary sources.

The paper “Forgotten Mediterranean calving grounds of gray and North Atlantic right whales: evidence from Roman archaeological records” has been published in the journal Proceedings of the Royal Society of London B.

Llanocetus denticrenatus

Early baleen whales were fearsome predators with wicked teeth, but lost them entirely

Baleen whales (parvorder Mysticetes) haven’t always been ‘baleen’, new research shows — and this unique adaptation hasn’t evolved from teeth, as previously suspected.

Llanocetus denticrenatus

A reconstruction of Llanocetus denticrenatus.
Image credit Carl Buell.

Today’s baleen whales are truly distinctive. Their most distinctive feature, the baleen — the comb-like filter-feeder system such whales use to capture krill — is so unique, we’ve used it to name the whole group. According to new research, however, the group didn’t always sport this specialized feeding apparatus. Just 34 million years ago, they were using good ol’ fashion teeth to do some good ol’ fashioned chomping with, one fossil reveals.

Teethy giants

“Llanocetus denticrenatus is an ancient relative of our modern gentle giants, like humpback and blue whales,” says lead author Felix Marx of the Royal Belgian Institute of Natural Sciences. “Unlike them, however, it had teeth, and probably was a formidable predator.”

Although you wouldn’t tell by their girth, whales actually originate from land mammals. Because of this, researchers knew the whales had to pick up filter-feeding after retreating back to the oceans (since you can’t really filter-feed on land). Up until now, common wisdom held baleen whales first started filter-feeding back in the days they still had teeth, but this may not have been the case.


Skull of Llanocetus denticrenatus. (A) Dorsal view. (B) Ventral view.
Image credits R. Ewan Fordyce, Felix G. Marx, (2018) / Current Biology.

Just like modern whales today, Llanocetus denticrenatus sported a series of distinctive grooves on the roof of its mouth (palate), the team reports. These grooves create the space necessary for blood vessels that supply the baleen in present-day Mysticetes. In Llanocetus, however, the grooves are clustered around teeth sockets — which suggests that they were feeding gums and teeth, not baleen. Baleen is fragile and would have been too exposed in such areas, liable to be crushed. Instead, the Marx suspects that the beast “simply had large gums and, judging from the way its teeth are worn, mainly fed by biting.”

Given that Llanocetus could grow to about 8 meters (26.2 feet), it likely had to do a lot of biting to keep reasonably fed. Thankfully for it, it came equipped for the job, the team finding a row of sharp, widely-spaced teeth with marked wear embedded in its rostrum.

I asked Ewan Fordyce, Professor at the Department of Geology at the University of Otago, New Zealand and paper co-author about what Llanocetus‘ meals likely consisted of. He admits that the team is “not sure” yet what this toothy whale hunted, but that its anatomy can yield some clues:

“It was probably not a top predator, Because these small teeth could only deal with medium-sized prey,” he told ZME Science in an e-mail. “It ate prey that was processed in part at least by teeth that could shear and pierce. Perhaps took small to medium-sized fish, not too bony, and maybe squid.”

Feeding apparatus

Feeding Apparatus of Llanocetus denticrenatus.
Image credits R. Ewan Fordyce, Felix G. Marx, (2018) / Current Biology.

The team’s findings suggest that baleen actually evolved from the gums, not the teeth themselves. The soft tissue gradually became more complex over evolutionary time and developed into the baleen, the team writes. This transition likely happened after the whales had already lost their teeth, and switched from biting larger victims to slurping in small pray. Marx and Fordyce believe that baleen evolved as a way to more effectively keep such prey inside the animals’ mouth — meaning they had to already be doing it for evolution to favor the baleen.

One factor that could be behind this change of menu is simple economics:

“Felix and colleagues have made the point that by feeding on small food, baleen whales move down the food chain,” Fordyce added for ZME Science, “[where] they have more resources than if they were at the top of the food chain.”

The results show that the evolution of baleen whales was more convoluted than previously thought, the team says. Next, they’ll try to get a better understanding of the baleen whales’ evolutionary path.

The paper “Gigantism precedes filter feeding in baleen whale evolution” has been published in the journal Current Biology.

Why whales are so big

The gentle giants of the oceans have fascinated people since time immemorial. Now, in a new study, researchers have found why whales grew to such impressive sizes — and why they don’t get even bigger.

As far as we know, the blue whale is the largest creature in history — which is a bit strange if you think about it. Even during the warm, lush times of the Cretaceous, when giant dinosaurs reigned supreme both on land and in the sea, nothing even came close to the blue whale.

It’s not just the blue whale as an outlier: several species of marine mammals grow to dramatic sizes. According to recent research, they have no other choice — their marine environment forces them to grow and grow.

“Many people have viewed going into the water as more freeing for mammals, but what we’re seeing is that it’s actually more constraining,” said co-author Jonathan Payne, a professor of geological sciences at Stanford’s School of Earth, Energy & Environmental Sciences (Stanford Earth). “It’s not that water allows you to be a big mammal, it’s that you have to be a big mammal in water – you don’t have any other options.”

Marine mammals as a whole are a pretty strange bunch. Contrary to popular belief, marine mammals have nothing in common with fish or other non-mammal sea creatures. Marine mammals started evolving some 50 million years ago, from land-dwelling creatures. To this day, they maintain many physical features from their terrestrial ancestors, despite their aquatic lifestyle. The most common theory is that they took to the sea in order to evade an overly competitive land environment and exploit an unfilled ecological niche in the sea. To paint an even weirder family picture, groups of marine mammals aren’t even related to each other — whales and dolphins are related to hippos and other hoofed land mammals, manatees share ancestry with elephants, while seals and sea lions are rather related to dogs.

In order to make sense of this unusual group, researchers compiled body masses for 3,859 living and 2,999 fossil mammal species from existing data sets (70% of living creatures, and 25% from extinct species). They found that as animals adapted to a more aquatic lifestyle, they quickly grew in size, converging at about 450 kg (1000 pounds). Using computer models to map and interpret the data, they drew a comprehensive picture of marine mammals and their mass.

“The key is having a phylogenetic tree to understand how these species are related to one another and the amount of time that has taken place between different evolutionary branching events,” said lead author Will Gearty, a graduate student at Stanford Earth. “The tree of ancestral relationships allows us to build models based on data from modern species to predict what the ancestors’ body sizes would have been and see what evolutionary trajectories best fit with what we see in the modern day.”

The reason why these animals grew so much and so fast, researchers say, is heat. Being bigger is simply more efficient in terms of conserving your own body heat.

“When you’re very small, you lose heat back into the water so fast, there’s no way to eat enough food to keep up,” Payne said.

So animals had an incentive to get bigger, but they also couldn’t get too big, otherwise they just couldn’t eat enough food to support themselves.

“Basically, animals are machines that require energy to operate. This need for energy places hard limits on what animals can do and how big they can be,” said Craig McClain of the Louisiana Universities Marine Consortium, who was a co-author on the study.

Interestingly, the sea seems to be a much more unforgiving place than land, as it allows for less variation. This lies in contrast with previous studies which claimed that evolutionary pressure is more relaxed in water as animals don’t need to support their body on legs.

“The range of viable sizes for mammals in the ocean is actually smaller than the range of viable sizes on land,” Payne said. “To demonstrate that statistically and provide a theory behind it is something new.”

Of course, there are also exceptions to this rule. At the lower end, we have creatures like otters. Otters took to the water much later than other creatures, and they still spend a significant part of their lives on land — these are probably the main reasons why they don’t follow the trend. At the other end, we have the true giants: baleen whales.

Baleen whales, which range in size from the 20 ft (6 m) and 6,600 lb (3,000 kg) pygmy right whale to the 112 ft (34 m) and 190 t (210 short tons) blue whale, broke the trend by completely changing how they eat. They don’t have teeth, instead filtering the oceans for zooplankton and krill. It’s this adaptation that allowed them to get so immensely big; without it, they would taper off in size and mass much faster.

“The sperm whale seems to be the largest you can get without a new adaptation,” Gearty said. “The only way to get as big as a baleen whale is to completely change how you’re eating.”

The study has been published in the Proceedings of the National Academy of Sciences.


Ancient whales had sharp predator teeth unlike today’s gentle giants

Ancient baleen ancestors had teeth as sharp as today’s lions which they used to slice prey to shreds, overturning long-held assumptions about baleen whale evolution. Modern baleen whales use a series of horny filtering combs that line the upper jaw.


Baleen whale ancestors had sharp teeth a new comparative-analysis suggests. Credit: Museums Victoria and Monash University .

At up to 29.9 metres (98 ft) in length and with a maximum recorded weight of 173 tonnes (190 short tons), the blue whale (Balaenoptera musculus) is the largest creature in Earth’s history. That may sound terrifying but this is a gentle giant whose diet consists almost exclusively of krill, a small oceanic creature that generally measures a measly 1-2 centimeters. It does eat copious amounts of it, consuming up to 40 million krill per day or 8,000 pounds simply by plowing the ocean with its bristle-like baleen structures that filter food from the water.

There are 12 baleen whale species divided into 4 families. However, there’s a second group known as the toothed whales (Odontoceti) since they use sharp teeth instead of baleen structures to catch prey. A prime example is the killer whales (Orcas Orca)which are actually dolphins.

[panel style=”panel-info” title=”Tooth whales don’t include ‘just’ whales” footer=””]Toothed whales make up one of two suborders within the cetacean species.

The term can be misleading since addition to whales the toothed whale suborder also consists of all species of dolphin and porpoise. [/panel]

From hunting to going for volume

A long-standing debate among scientists is when and how did baleen filter feeding appear. As early as Charles Darwin, scientists have speculated that baleen whale ancestors had teeth shaped like precursors to filter-feeding. But paleontologists at the Museums Victoria and Monash University reveal a different picture.
The team built 3-D digital models of ancient whale fossils and then compared them to modern mammals. They not only looked at modern whales but also four terrestrial extant species (lions, coyotes, pumas, and dingoes), as well as five seal species. That might seem like an odd analysis; after all, what do a lion and a humpback whale have in common? Not much, besides being both mammals, but the reality is scientists can learn a great deal about a species’ diet and feeding patterns judging from the size, orientation, and sharpness of teeth alone.

Tooth sharpness comparison between various ancient whales and modern carnivorous. Note the sharp cutting edges in the dingo and †Janjucetus. Credit: Carl Buell.

Tooth sharpness comparison between various ancient whales and modern carnivorous. Note the sharp cutting edges in the dingo and †Janjucetus. Credit: Carl Buell.

At the end of the day, the paleontologists surprisingly found that early whales such as Janjucetus, a 25-million-year-old species that co-existed with the forerunners of baleen whales, had teeth that were ‘optimized for slicing through flesh.’ In fact, they were just as sharp as today’s African lions!
This suggests that unlike today’s gentle giants, early whales looked like vicious predators.

“These results are the first to show that ancient baleen whales had extremely sharp teeth with one function—cutting the flesh of their prey,” Museums Victoria’s senior curator of vertebrate palaeontology Erich Fitzgerald said.

“Contrary to what many people thought, whales never used their teeth as a sieve, and instead evolved their signature filter feeding technique later—maybe after their teeth had already been lost.”

The baleen open question

In other words, ancient mysticeti — a term used to describe whales that feed using baleen — had teeth just as sharp and adapted for slicing meat as today’s most successful terrestrial predators and seals. They “never passed through a tooth-based filtration phase, and that the use of teeth and baleen in early whales was not functionally connected,” the authors wrote in the journal Biology Letters. 

While the results are quite revealing, they still leave the important question of how baleen filtering appeared in the first place unanswered. One hypothesis suggests baleen filtering co-existed alongside raptorial teeth through a period of overlapping until the baleen strategy eventually won — or at least for some species. Another possibility is that some early mysticeti evolved into suction feeders which came with tooth loss.

More fossils might provide the missing link that bridges the answer to this yet open question. There is already good progress. In May 2017, we reported the discovery of the 36-million-year-old Mystacodon selenensis, which literally means ‘toothed whale’.

Wear on Mystacodon’s teeth tells us that this was a suction feeder who vacuumed up its prey instead of chomping it with its sharp teeth. Suction feeding — possibly an intermediate step toward the filter-feeding strategy we see today in baleen whales — is common among living marine mammals, including seals, dolphins and toothed whales, who use it either to capture prey or to prevent it from floating away while they swallow.

Whale and calf.

A single ‘letter’ difference in their DNA made some whales huge, others sleek and predatory

A single-letter difference in their genetic code dictates whether a whale species will be sleek and slim — or big and fat.

Whale and calf.

No disrespect intended.
Image credits David Mark.

Genes dictate everything about how our bodies look, behave, and live. Changes in a genome, then, will have an effect on what the animal encoded by those genes ends up being. Even the minutest of changes can have a really big impact — case in point, cetaceans.

Huge results

A paper led by Liyuan Zhao, a marine biologist from Ocean University in China and co-authored by Roger Cone, an obesity researcher at and director of the University of Michigan Life Sciences Institute, reports that the variation of a single amino-acid in whales led some species to evolve muscular bodies and prey on fish and seals, while other species grew to be the biggest mammals alive today, filter-feeding on immense volumes of krill.

Cone has spent the better part of his career studying the melanocortin system. This is a collection of central nervous circuits dictates how much energy a body stores as fat. In humans, mutations affecting this system are one of the most common genetic causes of early-onset obesity, and it functions similarly in all mammals and fish. While at the lab for a visiting fellowship, Zhao picked up on the idea; given its central role in maintaining energy balance, she wanted to see if variations in genes affecting the melanocortin system could explain the evolution of such different feeding behaviors and body sizes in the two main whale suborders.

Odontoceti, such as dolphins and killer whales, hunt their meals and the smallest members of the suborder usually grow to around 1.5 m (5 ft.) in length. In stark contrast, Mysticeti, such as humpback or blue whales, are filter-feeders which can grow well over 30.5 m (100 ft.).

Tiny causes

Working together with co-author Antonis Rokas, a Professor at the Vanderbilt University of Nashville’s Department of Biological Sciences, the two obtained DNA samples of 20 whale species from an existing repository at NOAA’s Southwest Fisheries Science Center in La Jolla, California. They were looking for the genes encoding the MCR4 neuropeptide receptor (a key receptor in the melanocortin system) and found one single difference, which perfectly correlated with one of the two groups:

Odontoceti (toothed whales) have the amino-acid arginine (A) in position 156 of their genetic code. Mysticeti (baleen whales) have glutamine in the same position of the genome. The team tied glutamine in this position to an increased sensitivity of the MCR4 receptor to the transmitter molecule that activates it.

“Our data suggest that the melanocortin system is more highly regulated in whales that hunt — and, conversely, that the giant filter feeders may receive reduced satiety signals from this system,” Cone explains.

“This difference could well have played some role in the divergence of these two major types of cetaceans — and may help explain the differences in feeding behavior and amazing range of body sizes among whales, which is far greater than in any other type of mammal.”

The team’s main interest is to take the results from “bench to bedside” and apply them to human health. Cone also joked that the research could go from “bench to barnside,” as the U.S. Department of Agriculture and the United States-Israel Binational Agricultural Research and Development Fund have funded the lab to apply their insight into feeding and growth of different species to improve feed efficiency in fish farms.

The paper “Functional variants of the melanocortin-4 receptor associated with the Odontoceti and Mysticeti suborders of cetaceans” has been published in the journal Scientific Reports.

Blue Whale.

Ancient climate change turned whales into Earth’s largest organisms ever , study reports

Ancient shifts in climate may have powered the baleen whale’s growth to such “ginormous” sizes, a new paper reports.

Blue Whale.

“Ginormous” seems rather fitting.

With some individuals growing to be the length of an average basketball court and weighing upwards of 200,000 kilograms (441,000 pounds), the blue whale is big fry indeed — in fact, they’re believed to be one of the largest animals that have ever lived on Earth. Which naturally begs the question of what led them, and their kin, to grow to such proportions.

[Turns out that a long time ago, a larger-than-whales dinosaur roamed the Earth. Why not read about it?]

Up to now, biologists have had (and debated over) two main theories in regards to why. The first one is that whales simply grew because they could, as water provides a lot of buoyancy for their bodies. So although they’d weigh a lot on dry land, way too much to be able to even move, they’re pretty nippy underwater and can still catch prey quite easily. The other theory is that the whales grew out of necessity, as their monumental size made them virtually immune to the attacks of giant sharks or other mega-predators.

Another point of interest is when they got so large. One paper published in 2010 under the lead of Graham Slater, an evolutionary biologist currently at the University of Chicago in Illinois, estimates that cetaceans (the whale’s extended family) split into size groups around 30 million years ago. It’s a lineage that still holds today, the paper argues — so the baleen whales trace their ancestry to the giant group, predatory whales (such as the beaked whale) hail from the middle-sized group, and dolphins from the runts of the litter, becoming the smallest of cetaceans.

Chubby cheeks

A new paper however could address both questions in one single swoop. Penned by Slater alongside Nicholas Pyenson, a whale expert at the Smithsonian Institution’s National Museum of Natural History in Washington D.C., and Jeremy Goldbogen at Stanford University in Palo Alto, California, the paper proposes that the whales’ size is a product of environmental stresses associated with global cooling in the Neogene some 4,5 million years ago.

The paper started taking shape a few years ago when Pyenson and Slater started working with the museum’s cetacean fossil collection to see if the diverging lineages theory holds water. Previously, Pyenson studied living whale populations to determine that a whale’s total size correlated well with the width of its cheekbones. So the duo gathered this numbers for 63 extinct whale species and 13 contemporary ones and plotted these values over the family’s timeline.

The trend showed that there weren’t any big whales early on, contradicting Slater’s earlier theory. There wasn’t any gradual increase in size over time, either — instead, what the team saw was that whales became moderately large and stayed so up until about 4.5 million years ago. After this, baleen whales suddenly grew “from relatively big to ginormous,” Slater says.

In case you’re not familiar with the ginormity scale, whales 4.5 million years ago clocked in at around 10 meters (about 32.5 feet) long — whereas today’s blue whales grow to around 30 meters (98.5 feet). So evolutionary speaking, the whales’ size is a pretty recent development.

Long road, big fins

Whale Fins.

“Laters haters!”

The next step was to look at the going-ons of the time to see what caused this very dramatic, 300% increase in size. The team found that the growth coincided with the beginning of the first ice ages. They explain that the colder climate lead to an increase in glacier cover which would melt during the warmer months of spring and summer, sending cold sediment (and nutrient) rich runoff into coastal waters which supported plankton and zooplankton (who like cold waters) blooms — which the whales were more than happy to dine on.

The problem was that until then, this krill was evenly distributed in the oceans and relatively plentiful, so the whales could go anywhere they pleased and dinner would be waiting for them. But climate change killed off most of the ocean biosphere at the time (ironic isn’t it) and severely weakened existing ecosystems, drastically lowering primary and secondary productivity (the rate at which plants turn sunlight into organic compounds, and the rate at which animals turn plant matter into their own biomass respectively).

Combined, this changed the pattern of food availability from “decent food pretty much anywhere” to “truckloads of food in far-apart areas at certain times during the year,” and the whales had to adapt. Goldbogen, who studies whale eating and diving behavior, helped explain the link between food availability and size. The more concentrated food becomes, larger whales with really big mouths gain a huge boost to feeding efficiency, he says. Moreover, larger whales could travel between feeding areas faster and with less effort than smaller ones.

Overall, these two factors put huge selective pressures on growing larger frames, so the bigger species thrived while smaller whales went extinct.

The paper, while not being the first to show how food and feeding habits shaped whale evolution, does offer a simple and pretty elegant explanation for the whales’ size. It also goes to show that evolution is powered by an interplay of factors, from climate to the way other species adapt to present conditions. And finally, it shows that a species’ adaptation to one particular constraint — in the whales’ case, food availability — can inadvertently address some of its other needs — such as safety from predators — or provide an unexpected boon to ecosystems.

The full paper “Independent evolution of baleen whale gigantism linked to Plio-Pleistocene ocean dynamics” has been published in the journal Proceedings of the Royal Society B.

Mystacodon selenensis

Ancient 36-million-year-old fossil helps track down how baleen whales lost their teeth

Baleen whales, also known as mysticetes, are the largest animals in the world. There are 12 baleen whale species divided into 4 families, among them the famous humpback and blue whales. Some of the defining features of mysticetes, beyond their husky size, are the paired blowholes and the long plates of baleen which hang in a row (like the teeth of a comb) from their upper jaws. It’s through these baleen plates that the whales filter water to capture tons of krill, other zooplankton, crustaceans, and small fish. At one point, however, mysticetes had teeth and a newly discovered 36-million-year-old fossil skeleton is helping scientists unravel the timeline of this transformation.

 Mystacodon selenensis

A mysterious jaw

The new mysticete ancestor was discovered in the Pisco Basin, right on the southern coast of Peru, by paleobiologists from Europe and Peru. The new find is called  Mystacodon selenensis, which means “toothed mysticete” owing to the fact that this is the oldest member of the group found thus far. All early mysticetes had teeth, unlike their modern versions which all employ a hallmark adaptation: baleen, a series of horny filtering combs that line the upper jaw. We can still to this day see the legacy of the toothed mysticetes in animals like orcas, dolphins, and other toothed whales.

Gray whale baleen plates.

Gray whale baleen plates at the Beaty Biodiversity Museum in Vancouver, British Columbia.

At what point and what mechanism this transition employed are some of the questions scientists been asking themselves for a while. Mystacodon was gracious enough to answer some. For instance, judging from its age, we know for sure mysticetes still had teeth some 36 million years ago. We’ve also come to understand that the striking transition from sharp teeth to baleen didn’t happen overnight.

According to  Olivier Lambert, a paleontologist at the Royal Belgian Institute of Natural Sciences in Brussels and co-author of the new study, Mystacodon was likely only 4 meters long or about the size of a pilot whale.

Mystacodon also holds on to some primitive whale features like a protruding hip bone, a remnant from the time when the whale’s ancestors were 4-legged, terrestrial creatures. For its timeline, some scientists had through this hind limb would be more or less gone but the findings clearly show the transition took longer than previously believed. The process also happened independently in toothed whales, not one time in the common ancestor of both toothed and baleen whales.

 The skull of Mystacodon has as a flattened snout and a mouth full of teeth, which baleen whales later lost.

The skull of Mystacodon has a flattened snout and a mouth full of teeth, which baleen whales later lost.

That’s not to say that Mystacodon lacks modern features. Its snout was flattened just like any other modern mysticetes. Additionally, Mystacodon couldn’t move the joints in the front flippers, a feature shared by modern mysticetes. Earlier whales could still flex these front flipper joints, likely a relic of the time when the flippers were actually legs. As such, Mystacodon can be considered a nice example of the final step of the transition of the forelimbs into flippers, as reported in Current Biology.

The fossil teeth were also more abraded and the eye sockets were found to be higher up on the skull. All of these are signs that these ancient animals used to hunt at the bottom of the ocean as it’s the sand of the sea floor that often wears teeth to such a degree and the higher-set eyes can help the animal look forward above its snout.

Clever innovation — fishing with a net instead of a hook

The fact that Mystacodon used to be so small compared to, say, a blue whale that can grow to 29.9 meters (98 ft) in length and 173 tonnes in weight, can be easily attributed to the baleen innovation. This is a rather clever strategy that allows the modern mysticetes to cut out predatory middlemen and feast directly on the abundance at the bottom of the food chain. The transition from a toothed to a baleen jaw, however, has always proved problematic. How could hard, slicing teeth and comparatively soft baleen occupy the same space in the jaw, and yet not get in each other’s way?

Wear on Mystacodon’s teeth tells us that this was a suction feeder who vacuumed up its prey instead of chomping it with its sharp teeth. Suction feeding is common among living marine mammals, including seals, dolphins and toothed whales, who use it either to capture prey or to prevent it from floating away while they swallow. Some scientists believe that suction feeding is a step toward the filter-feeding strategy we see today in baleen whales, considering early mysticetes show similar signs of wear. The connection between the two feeding mechanisms, however, is not clearly established.

To get to the bottom of things, scientists will have to dig more and deeper. A good place to start is in the same Peruvian desert where Mystacodon was unearthed where there’s a huge potential for excavations.

Scientists believe they’ve identified the source of the mysterious sound coming from the Mariana Trench

The first audio recordings from the Mariana Trench, the world’s deepest point, are creepy as hell.

Deep-sea rover exploring the Mariana Trench. Credit: NOAA

Among the sounds captured by an autonomous vehicle, an eerie 3.5 segment was especially mysterious, and it was captured several times from autumn 2014 to spring 2015. In other words, scientists couldn’t figure out where it was coming from – or what made it. After months of analysis, they might finally have the answer: a whale signal, unlike any other we’ve heard before.

“It’s very distinct, with all these crazy parts,” says one of the team, Sharon Nieukirk from Oregon State University. “The low-frequency moaning part is typical of baleen whales, and it’s that kind of twangy sound that makes it really unique. We don’t find many new baleen whale calls.”

The sound spans frequencies as low as 38 hertz and as high as 8,000 hertz – humans can hear between 20 and 20,000 Hz, so it’s within audible range, and it covers a very broad frequency. Because sound waves travel great distances in water, the source can be kilometers away so it could be almost anything. Without knowing where to start, they began to eliminate possible sources. Firstly, they eliminated man-made sounds.

“The sounds reported here are not similar to known anthropogenic sources such as noise produced by ships or seismic airguns,” the team reports.

Visual representation of the recording, showing five distinct parts. Credit: S. L. Nieukirk et al.

Then, they moved on to geological sounds but again, nothing fit the sound profile, and in the end, all they were left with was a biological source – a whale.

“They also do not resemble geophysical sources such as the very low-frequency sounds produced by earthquakes and ice, nor the sounds produced by wind or rain. … [We] hypothesise that these complex sounds were produced by a biological source.”

Although these sounds are absolutely unique in recorded history, Nieukirk found an equally bizarre recording from Australia’s Great Barrier Reef, coming from dwarf minke whale – the so-called Star Wars minke call. Although different, the minke whale call had some similarities to the Mariana Trench one, in terms of frequency and structure.

“The complex structure of the Western Pacific Biotwang sound, the frequency sweep, and the metallic nature of the final part of this call are all very similar to characteristics of dwarf minke whale Star Wars calls,” the team concludes.

But even if this is a call from minke whales, the big question still remains: what kind of a call is it? The first option would be a mating call, but mating calls are seasonal, and this sound was heard constantly.

“If it’s a mating call, why are we getting it year round? That’s a mystery,” says Nieukirk. “We need to determine how often the call occurs in summer versus winter, and how widely this call is really distributed.”

If it’s something else… then again – what could it be? In the end, as Nieukirk says, good science will explain it.

“It really is an amazing, weird sound, and good science will explain it,” says Nieukirk.

Journal Reference: Sharon L. Nieukirka, Selene Fregosi, David K. Mellinger, and Holger Klinck. A complex baleen whale call recorded in the Mariana Trench Marine National Monument. The Journal of the Acoustical Society of America > Volume 140, Issue 3 > 10.1121/1.4962377

Whales as Ecological Engineers


Credit: Pixabay.

Given the sheer size of whales, it should be no surprise that they make some very important contributions to ecosystems. What you may find surprising is the form that some of these contributions take. When we think of ecological engineers we tend to think of elephants, beavers, and corals, but the open ocean is also a fluid system where whales hold significant influence.

There is a tendency for nutrients in the form of biological material to slowly sink away from the surface into deep ocean environments. This downward migration of debris is referred to as a biological pump, and the debris itself is called marine snow. The nutrients in marine snow can become tied up in ocean floor sediments or dissolved in water that may take decades, if not centuries, to resurface. Consequently, ecosystems at the surface of the ocean are often nutrient-poor, whereas cold, deep water is often nutrient-rich.

It turns out that whales help to even the balance by a simple mechanism called a whale pump. They feed at varying depths, but they seem to defecate almost exclusively at the surface. These massive clouds of poop provide a big boost of iron and nitrogen to the ecosystem, and since whale excrement is mostly liquid, those nutrients are more likely to remain in suspension than sink. For a species that feeds at great depths, such as sperm whales, this pump effect would be very pronounced.

The whale pump phenomenon was first formally observed in 2010, so we are still honing our understanding of it. Quantitative estimations so far confirm that they transport sufficient nutrients to significantly enhance the productivity of surface-water environments (Roman and McCarthy 2010).


The biological pump transports nutrients away from the surface whereas the whale pump brings them back. (Roman and McCarthy 2010)

Whales don’t just engineer ecosystems; They create them. When a whale dies, it’s carcass sometimes descends all the way to the ocean floor. Within days of it’s arrival, scavengers will have converged from far and wide for a feast.

There are various stages that whale fall ecosystems progress through. Initially, there is a swarm of fish, sharks, and crabs that are capable of tearing through the tough blubber. As the carcass becomes more degraded, most of the larger organisms depart leaving the smaller scavengers like starfish to consume the residual tissues. Eventually, only bones remain, along with the bacteria, worms, and clams they support. There isn’t a clear consensus on how long whale falls persist, but 10-20 years seems to be a safe estimation.


The diversity found at whale falls rivals that of hydrothermal vents (Smith and Baco 2003), and whale falls are almost certainly more abundant. Unfortunately, in part due to the difficulty of locating and accessing them they haven’t been particularly well studied. What is clear is that these are one-of-a-kind ecosystems, and their abundance is directly tied to that of whales.

Whale populations have suffered greatly in recent centuries, largely thanks to the advent of whaling, and have never fully recovered. By conservative estimates, the historical global population was 6 times greater than it is today (Roman and Palumbi 2003). With their unique ecological contributions taken into consideration, this dramatic decline is likely to have had profound effects throughout the oceans. Therefore, it may be wise to rethink what we consider to be the natural state of our oceans.

This is an article by Steven Sande. Steve is an aspiring environmental professional from Ontario, Canada. You can find more of his work at stevenandrewsande.com.


Roman, Joe, and Stephen R. Palumbi. “Whales before whaling in the North Atlantic.” science 301.5632 (2003): 508-510.

Roman, Joe, and James J. McCarthy. “The whale pump: marine mammals enhance primary productivity in a coastal basin.” PloS one 5.10 (2010): e13255.

Smith, Craig R., and Amy R. Baco. “Ecology of whale falls at the deep-sea floor.” Oceanography and marine biology 41 (2003): 311-354.

Humpback whales bounce back from the brink of extinction

Humpback whales have made an epic return. Nine out of 14 distinct populations have now been crossed off the federal endangered species list. Four populations retain their endangered status, while one is listed as threatened.

Humpbacks frequently breach, throwing two-thirds or more of their bodies out of the water and splashing down on their backs. Photo by Wwelles14.

Conservation efforts do work, at least when they’re done properly. It took 50 years, but international efforts to protect humpback whales have been met with success as the numbers increased steadily decade after decade.

Humpback whales were almost hunted to extinction in the 19th and 20th century, mostly for their meat and fat, which was used much like oil. But a moratorium was passed in 1966, effectively banning whaling – and this was the key turning point for the whales. Now, after almost half a century, they’re finally off the endangered list.

“Today’s news is a true ecological success story,” Eileen Sobeck, assistant administrator for fisheries at the National Oceanic and Atmospheric Administration, said in a statement.

The feeling was echoed by many groups who reported seeing plenty of whales and wanted this change to underline a healthy recovery.

“We just saw a lot of whales. So we thought this is a success in ocean management and we wanted to point that out to the world – that things are good with whales in Hawaii,” said Phil Fernandez, president of the Hawaii Fishermen’s Alliance for Conservation and Tradition.

The image above, provided by NOAA, shows the 14 newly-identified humpback whale population segments and their migratory patterns.

Angela Somma, chief of NOAA Fisheries’ endangered species division, said “very little will actually change” in efforts to protect whales. According to her, humpbacks will still receive protection and the International Whaling Commission’s moratorium on commercial whaling will also remain in place.

“Many of the day-to-day protections and activities will continue to occur,” Somma said in a call to reporters Tuesday. “We will continue to work and maintain their conservation.”

However, not everyone agrees with this. Several biologists and conservationists have asked for continued protection on the endangered list.

According to the Miami Herald, Center for Biological Diversity attorney Kristen Monsell said that humpback whales face significant and growing threats, including getting entangled in fishing gear. She says the protections should stay in place for the whales.

It is true that even without whaling, humpbacks face growing challenges. They are vulnerable to collisions with ships, entanglement in fishing gear and noise pollution.

“These whales face several significant and growing threats, including entanglement in fishing gear, so ending protections now is a step in the wrong direction,” Kristen Monsell, an attorney with the Center for Biological Diversity, said in a statement.

Hopefully, the recovery won’t backfire and humpback whales will enjoy their recovery as time passes on.

Four populations are still considered endangered, including those that frequent waters in the Pacific Northwest, Central America, the Arabian Sea and northwest Africa.

Whales mourn, and grieve, and feel the loss of a loved one — just like you or me

A new study has found evidence of mourning behavior in more than six species of marine mammals. The animals have been seen clinging to the bodies of dead relatives or podmates, refusing to let go — a behavior similar to that of human grieving.

A mother orca with her dead newborn.
Image credits Robin W. Baird/Cascadia Research

The most likely explanation behind the animals’ observed behavior is grief, the researchers believe. Barbara King, emeritus professor of anthropology at William & Mary in Williamsburg, Virginia, and author of the book How Animals Grieve, defines animal grief as emotional distress coupled with a disruption of usual behavior.

“They are mourning,” says study co-author Melissa Reggente, a biologist at the University of Milano-Bicocca in Italy. “They are in pain and stressed. They know something is wrong.”

There is previous evidence of a growing number of species that seem to be stricken with grief at the loss of a family member. Elephants will even return over time to the resting place of a dead companion. All this lends weight to the argument that animals feel emotions. Throwing their hat into the controversy, Reggente and her colleagues gathered reports (most of them yet unpublished) of grieving behavior in seven whale species, from sperm whales to spinner dolphins. Their study found that all of these species have been reported to keep company with their dead around the globe. They’re not just isolated cases, either.

“We found it is very common, and [there is] a worldwide distribution of this behavior,” Reggente says.

And the animals seem to understand exactly what they’re doing. In one case, researchers on a boat in the Red Sea watched an Indo-Pacific bottlenose dolphin push the badly decayed corpse of a smaller dolphin through the water. When they lassoed the dead body and begun towing it towards land to bury it, the adult swam alongside the body, occasionally touching it. It escorted it until the water became dangerously shallow, and remained just offshore long after the carcass had been taken away. The relationship between the two dolphins isn’t clear, but Reggente believes they were either mother and child or close kin.

This behavior is even more striking when you consider just how costly it is for the animals. Keeping vigil over a dead companion means that the animals don’t feed and aren’t interacting with other whales, putting it at risk of starvation or social exclusion.

On other occasions, the scientists did have clues about the relationship between the mourner and the dead animals. One female killer whale, known as L72, was seen off San Juan Island in Washington carrying a dead new-born in her mouth. L72 showed signs of recently having given birth, and the researchers observing it reported that it was likely due to have another.

“She was trying to keep the [dead] calf up at the surface the entire time, balancing it on top of her head,” says study co-author Robin Baird of Cascadia Research Collective in Olympia, Washington, who witnessed the mother’s efforts.

A killer whale mother and her offspring may spend their whole lives together, he adds. When one dies Baird believes that “the animals go through a period where they’re experiencing the same kind of emotions you or I would when a loved one dies.”

The study also found reports of whales holding dead calves in their mouths, pushing them through the water or touching them with their fins. Grieving can also involve a whole community of whales — in one case, short-finned pilot whales in the North Atlantic Ocean created a circle around one adult and dead calf, seemingly protecting them.

Another case involving spinner dolphins took place in the Red Sea. Here, one adult pushed a young animal’s body toward a boat, and when the vessel’s crew lifted the carcass on board, the entire group of dolphins nearby circled the boat and swam off.

“We cannot explain why they did this,” Reggente says.

“Sure, sometimes we may be seeing curiosity or exploration or nurturing behavior that just can’t be ‘turned off,’” King said. “[But] it’s undeniable that we can also read something of the animals’ grief in the energy they expend to carry or otherwise keep dead infants afloat, to touch the body repeatedly, to swim in a social phalanx surrounding the primary affected individual.”

This behavior certainly has an element of curiosity or remanent nurturing instincts behind it, but they can’t, by themselves, explain what we’re seeing these animals do. They expend a whole lot of energy, either individually or as a group, in their rituals of carrying or keeping dead individuals afloat. The social interaction, centered on supporting the grieving individual, is also highly reminiscent of human society when confronted with the loss of its members.

We all know the pain and harrowing loneliness of losing a loved one, and it seems whales do too. The question now is how will we treat these animals, knowing they feel the same way as we do.

The full paper, titled “Nurturant behavior toward dead conspecifics in free-ranging mammals: new records for odontocetes and a general review” has been published online in the Journal of Mammalogy and can be read here.

Norway is now the world’s leading whaling nation

Norway is killing more whales than Japan and Iceland combined.

This is how whaling should be – a historical and long-abandoned practice.

They get a lot of praise for their progressive society and high living standard, but at least in one regard, Norway definitely doesn’t deserve any praise: whaling. A new report released today, calls on the international community to respond to Norway’s systematic whaling expeditions and efforts to loosen international regulations on whaling.

“As one of the world’s most modern and prosperous countries, Norway’s whaling is an anachronism,” said Dr. Sandra Altherr, biologist with ProWildlife. “Slaughtering whales to eat and trade has no place in Norway and serves only to diminish the country’s international reputation.”

But the country’s whaling industry doesn’t seem interested in preserving the international reputation. The Norwegian government itself is funding a number of projects to promote not only whale sales, but also alternative commercial products derived from whales, including dietary supplements, medicines, and cosmetics. In fact, whale oil seems to be a highly desired product in the Norwegian cosmetic industry.

“We were stunned that a Norwegian whaling company is actively selling health and beauty products manufactured from whale oil,” said Susan Millward, AWI executive director. “This is not the 1800s. It is incomprehensible that such a modern nation produces skin creams sourced from an inherently cruel industry.”

The sheer number of killed whales is also saddening. Frozen in Time: How Modern Norway Clings to Its Whaling Pastproduced by the Animal Welfare Institute (AWI), OceanCare and Pro-Wildlife, writes that Norway is not only the world’s leading whaler, but it kills more whales than the second and third place combined. Also, Norway uses their international leverage to escape criticism and carry on with business as usual.

“The IWC has not formally commented on Norway’s whaling since 2001 and the international community has not presented a demarche to Norway since 2006,” stated Sigrid Lüber, OceanCare president. “For as long as this remains the case, Norway will continue to let Iceland and Japan take the heat for whaling and maintain its business as usual.”

It’s indeed an anachronic situation, and one that shouldn’t really happen — not when we’re talking about a nation like Norway, and not in 2016.

Japan resumes whaling despite international ban

The island nation has recently announced that it will resume whaling operations in the Antarctic Ocean with the purpose of collecting “scientific data.” The decision was met with outrage and heavy criticism by other countries and conservation groups.

Minke Whales
Image via flikr

The IWC commissioner for Japan, Joji Morishita, announced in a series of new documents to the International Whaling Commission (IWC) that his nation is resuming whaling operations in the Antarctic (or Southern) Ocean starting 2016, with a target of some 333 minke whales per year. All in the name of scientific progress, they claim:

“In order to achieve conservation of [Antarctic] resources while pursuing their sustainable utilisation and to understand and predict the effects of factors such as climate change, it is scientifically imperative to obtain an accurate understanding of many aspects of the Antarctic marine ecosystem including its animals and their dynamics through collection, accumulation, and analysis of scientific data,” Japan’s whaling research plan states.

Japan’s in no way, shape or sense new to whaling — their previous operations in the Antarctic Ocean were ended after the International Court of Justice ruled against them in March 2014. While Japan claimed that its whaling in this region was justified under the 1946 International Convention for the Regulation of Whaling on grounds of scientific research, the court found that the research output from almost a decade, two studies based on nine whale specimens, was woefully insufficient for justifying the program and the scale of the slaughter.

“In light of the fact the [research program] has been going on since 2005, and has involved the killing of about 3,600 minke whales, the scientific output to date appears limited,” said presiding judge Peter Tomka of Slovakia during the ruling.

So the international community shut the whaling program down for good, they thought. But Japan now announced that it will keep on whaling regardless of the ICJ’s ruling with a new, amended program that plans for the killing of only 1/3 of the whales that their initial program had planned.

However, let’s be serious — it’s hard to justify a scientific program that requires the killing of 333 whale specimens per year. Japan’s decision has been met with outrage from conservation groups and representatives of other nations who are party to the IWC’s moratorium on commercial whaling.

“We do not accept in any way, shape or form the concept of killing whales for so-called ‘scientific research’,” said Greg Hunt, Australia’s minister for the environment. “Japan cannot unilaterally decide whether it has adequately addressed the [scientific] questions. There is no need to kill whales in the name of research. Non-lethal research techniques are the most effective and efficient method of studying all cetaceans.”

Adding his voice to the critics is Tokyo-based historian Jeff Kingston, who wrote for The Japan Times saying that Japan’s resumption of whaling flouts the rule of law and would have negative repercussions outweighing any potential upsides for the country’s whaling industry.

“Whaling advocates in the Japanese government may think they are justified on cultural and culinary grounds, but they are harpooning ‘Brand Japan.’ Japan’s scientific argument for the resumption of whaling was examined and found wanting by two international panels of experts,” he wrote.

“Moreover, in terms of Japan’s global public image, whaling is a losing proposition. It’s a diplomatic scarlet letter that negatively influences public opinion in Europe, North America and Australia over a program that uses taxpayer money to kill something that hardly anyone craves – all for the sake of a national identity that few embrace.”

It’s not yet clear what the repercussions will be for the island nation, but we’re likely to see the world’s reply to Japan’s whaling program soon.