From the frothy crests of the Atlantic to the shadowy depths
of the Mediterranean, this whale of paradoxes reigns supreme as the champion of
breath-hold and deep‑sea endurance. Deep beneath the Mediterranean’s azure
waves, the creature defies mammalian biology with such audacity that scientists
initially refused to believe their instruments. Meet the Cuvier’s beaked whale
(Ziphius cavirostris). It is the unassuming heavyweight champion of deep-sea
diving who is capable of holding it’s breath for nearly 4 hours and plunging to
depths where the pressure would crush nuclear submarines. Forget Everest; this
is the final frontier of survival on Earth.
 |
| Illustration of a Cuvier's beaked whale according to NOAA |
Imagine a world cloaked in perpetual darkness where daylight fades a mere few hundred metres beneath the surface. Here, at depths approaching 3 km, pressure mounts to over 300 bar which is enough to crumple steel. Yet in this alien realm thrives Cuvier’s beaked whale (Ziphius cavirostris) – a creature so exquisitely adapted that it routinely shatters mammalian records. Few creatures push the boundaries of endurance and physiology quite like the Cuvier’s beaked whale.
In this deep-dive exploration, we’ll reveal the astonishing
physiology, quirks, controversies and conservation challenges behind this
enigmatic cetacean. From ancestral roots to modern threats and from
record-shattering breath-holds to cutting-edge research, this blog explores
every facet of their jaw-dropping existence in THE deep. You will want to hold
on tight!
Table of contents
The physiology that powers their feats
From wolves to abyssal hunters – Evolutionary wizardry
How Cuvier’s dives dwarf other giants
Hunting in darkness, healing in silence – Life in the abyss
Death by mimicry and the plastic plague – Controversies
Why the abyss needs ambassadors
Conservation efforts and the future
Recent discoveries from the year 2024
The ocean’s ultimate endurance artists
References and suggested reading
The records
For starters…to really understand their tenacity, we have to
read the expedition logs of Dr. Alistair Finch who is a Marine Biologist. His
logs provide us insights into the whale’s incredible capacities. From one of
his logs during an expedition...
We’ve been tracking Ziphius cavirostris for 72 hours now. They are phantoms – surfacing just twice a day, leaving only a wispy blow and scarred dorsal fin visible before vanishing. Why the scars? Males duel with tusk-like teeth (the only two they possess), carving grooves into rivals’ skin. Females? Near-flawless. A cetacean beauty standard, if you will. Their ‘panda eyes’ – dark patches around sunken eyes – aren’t makeup. They are acoustic fat pads focusing echolocation clicks into a biological sonar cannon. Perfect for hunting in the hadal zone, 3km down where sunlight fears to tread.
 |
| Credit - Anaïs Remili |
See, it is a modest-sized whale (upto 7 metres long and
weighing upto 3,000 kgs) with a ‘goose-like’ beak, a permanent panda-eye
complexion with bodies scarred by cookie-cutter sharks and male rivals. There
you have it…that’s the Cuvier’s beaked whales. Unlike the breaching humpbacks or
charismatic orcas, Cuvier’s are the introverts of the cetacean world. You will
barely get to see them in the wild unless you purposefully search for them
underwater. They surface inconspicuously, breathe for roughly two minutes and then
vanish for marathon dives averaging 60-90 minutes. This period is longer than a
feature film!
In the year 2014, researchers off California sat stunned as
data streamed from satellite tags. It told them that one Cuvier’s had remained
submerged for 137 minutes. That record would be soon smashed 6 years later which
would be a feat equivalent to a human running a marathon underwater without
breathing. As Dr. Nicola Quick (Duke University) remarked…
“It goes against what we think mammals should be able to do!”
“When I first saw a 137‑minute dive, I thought my tag must be broken! Then we realised Mother Nature had simply set a new benchmark”.
…admits Dr Erin Falcone, the pioneer of MFAS response
studies.
 |
| Dr. Erin Falone |
This whale is one of the greatest record-breakers of the
deep oceans. They are truly masters of the deep with incredible skills to flex.
The physics of their dives can only be what seems to us as impossible dives.
Their record‑shattering deep dives are not only unbreakable but are beyond human
comprehension. Some of their amazing feats are listed below.
Deepest dive – The record for their maximum depth is
2,992 metres or 9,816 feet as recorded in the year 2014. The whale spent over 2
hours in the abyss which remains far beyond any human‑built submersible’s
typical operational limit. That is almost 3 kilometres below our feet or the
waves…absolutely crazy! A deep-sea plunge was documented off Southern
California of the United States. Natural History Museum in the UK have more
information on this particular feat. It is still the record for any mammal from
surface to depth and back again.
Longest dive – They are also the masters of holding
their breath underwater for the longest time. At an astounding 3 hr 42 min
(222 minutes) in the year 2020, it smashed the previous record of 2 hours. A
separate satellite tag confirmed the record time. Scientists initially
questioned the data integrity until repeated tags confirmed these marathon
dives were no anomaly. Can you imagine diving into water once and holding your
breath for 4 straight hours? The staggering dive officially made history as the
longest dive ever documented for any mammal on Earth. Human freediving records
pale in comparison to this seemingly super‑mammal.
Foraging cycles – Median foraging dives of these
whales last about 59 minutes with the top 5% exceeding 78 minutes. They use the
time to forage for food during that specific timespan. Dives over an hour are their
routine. They do not resurface for extended periods of time. And even then,
their surface intervals remain brief. They resurface for air and stay afloat
for around 2 to 8 minutes before plunging into the depths again. Tagged whales
occasionally vary wildly in their foraging patterns. Some surface for under
20 minutes after extreme dives while others take over 4 hours to recover. This
individual variation hints at personal ‘choice’…perhaps driven by
stress, prey availability or sonar disturbance.
To put it in perspective, the record-holding human is
Budimir Sobat from Croatia. He managed to hold his breath for a mere 24 minutes.
And, even that did not come easy. He had to undergo a long period of training
for it plus take oxygen assistance. These durations dwarf other mammals (even
human freedivers), shattering every expectation. The whales lounge below for
longer than a blockbuster film.
The physiology that powers their feats
Let us dissect their 222-minute dive record (2020, Cape
Hatteras). This is really interesting because it numbs our head by just imagining
or roleplaying as the underwater mammal.
Oxygen banking – They are mammals just like us. But,
their haemoglobin concentration is 60% higher than humans. Meaning, the sheer
amount of blood cells will ensure that they are holding oxygen more than us.
Each blood cell holds oxygen and travels through the body. They have massive
oxygen stores by which they are able to successfully hoard oxygen and keep stockpiling
them like a scuba tank. Remarkably, they can extract up to 90% of oxygen per
breath which is a vast advantage than human efficiency. Where humans extract
~15% of lung oxygen, these whales scavenge up to 90% per breath. Wish we could be
like them.
Muscle myoglobin – They have denser muscles compared
to us. An every day Cuvier’s has 6x denser muscles than the most elite human
freedivers. Being 7 metres in length of those dense muscles, comes with
high-end advantages like the Cuvier’s. They are rich in blood and muscle
concentrations of haemoglobin and myoglobin. They have a dark interior because
of trapping plenty of myoglobin. Their muscle tissue is heavily pigmented with
myoglobin which has earned it a near-black appearance. Myoglobin-rich muscles
appear nearly black. Those muscles are perfect oxygen reservoirs for their
marathon dives.
Spleen – Their spleen is many times better than ours.
The spleen of the Cuvier’s acts something like an ‘oxygen battery’. It
keeps contracting to flood blood with extra O₂ pre-dive. The Cuvier’s spleen
"oxygen bombs" their body by contracting to flood circulation with
extra oxygen. With ample oxygen circulating throughout the body, they won’t
need to resurface for air any time soon. They are in no rush since there is no
rush.
Pressure defiance – At 2,992 metres (their deepest
recorded dive), the pressure = 300 times of the atmospheres (like an elephant
balancing on a postage stamp). Hence, survival hinges on radical anatomical
adaptations and evolution has gifted them with the right tools to mitigate the
problem. They have collapsible airways that prevent nitrogen narcosis. Under
pressure, their ribs fold, lungs compress to 1/20th volume and all the air
shifts to their rigid nasal passages. Their collapsible thorax is what keeps
them capable of deepest dives. Flexible rib cages implode under pressure,
collapsing their lungs and forcing air into the windpipes. This prevents
nitrogen absorption which is a killer behind the dreaded phenomena called ‘bends’.
Without this lung collapse technique, they would not be able to dive deep as
they do. Their rib cages fold to avoid the bends and minimise nitrogen
absorption. This will not only keep them alive but also conscious. Ribcage
folding and lungs collapsing, prevents compression injuries and enables safe
freedom from buoyant air pockets. Minimal nitrogen uptake is vital to avoid
decompression sickness in repeated deep dives.
Metabolic shutdown – Their system becomes adaptive to
conditions. Their heart rate drops down drastically to 2 bpm and all digestion
halts. It is lower than their hearts beating during their resting time. During
rest, their heart beats at 60 bpm. Their blood circulation also gets tweaked to
accommodate deep dives. Blood flow reroutes only to the brain and heart. There
is no much blood flow to their extremities during the time needed. Their livers
and kidneys enter stasis mode while deprioritising blood circulation to the limbs
and for digestion. They cease all such temporary functions for the time required.
During the stasis period, no urine production either happens for hours since
digestion has been halted. This remarkable bradycardia slashes oxygen
consumption and prolongs endurance far beyond terrestrial mammals. Much of
their functions are put on hibernation to allow them to do what they do which
is smash records. The slowed metabolism is great boon for any creature of the
deep that love lingering at ocean bottoms. Because of it, non-essential organs
like the gut and kidneys suspend their functions for extended lengths. Due to
the metabolic downgrade, anaerobic respiration kicks in during record dives,
tolerating lactic acid buildup that would otherwise cripple other mammals. Their
metabolic rates are strikingly low for a cetacean of their size and often near
aerobic dive limits but capable of occasional anaerobic excursions into record
territory.
 |
| It's complete skeleton shows how collapsible it's ribs are |
Dive calculation – For a human freediver, the record
for holding breath for the longest time was 24 minutes, his O₂ consumption was 0.5L/min
and his lactic acid threshold was extremely low. However, everything is
king-size in the case of Cuvier’s beaked whales. Their highest breath-holding
record is almost 4 hours, their O₂ consumption lingers around 0.03L/min and
their lactic acid resistance is simply…Off. The. Charts. Their anaerobic
tolerance is the envy of divers. Even when oxygen runs low, they can still
endure lactic acid build-up much better than we could. They are successful in evolving
acid-buffering muscles.
Diving pattern – Their dive cycles often follow a particular
regime. The strict discipline allows them to achieve their deep dives and
holding of breath. They engage in long deep dives (often over an hour) followed
by several shallow ones with surface visits typically lasting only 2 to 8
minutes. Their behaviour in the deep seems to show that they have a encoded a rhythm
into their diving.
- Standard cycle – Several deep dives (often 1 – 2 km, 60 – 90 min) paired with short surface recovery (2 – 8 mins) and then followed by shallower dives.
- Variations galore – Recovery periods after long dives can range from under 20 minutes to over 4 hours. Like I mentioned earlier, this hints at their individuality in physiology or stress response.
The exercise helps them achieve deeper and longer dives
eventually.
Streamlined missiles – ‘Flipper pockets’ allow
them to tuck away limbs and hence they end up becoming hydrodynamic torpedoes.
Their dorsal fin sits far back which helps in minimising drag during vertical
plunges. They are born physicists of sorts, you could say. Their size and
stockiness is also another factor. The adults span only between 5 - 7 metres in
length and weigh up to roughly 3000 kilograms which is equivalent to a nice
shark. Cuvier’s beaked whales are bulbous and surprisingly squat comparable
with sleek dolphins. Their torpedo-like shape helps them to glide effortlessly
through crushing depths of the deep oceans.
Blubber springs – The 2024 biopsies revealed that
Cuvier’s equipped with collagen networks in blubber that rebound 5x faster than
sperm whales’ blubber. This aids in acting as biological shock absorbers for
the Cuvier, especially from the crushing pressures of a rapid deep dive.
These feats of diving have defied physiological models
predicting oxygen depletion after just 77 minutes and forced scientists to
recalibrate their understanding of anaerobic endurance. A mammal isn’t supposed
to be deprived of oxygen for as long as the Cuvier’s which has helped them set
the record. Even more astonishing? One whale completed a 78-minute dive, then
resumed deep foraging after only 20 minutes of recovery. This kind of metabolic
anomaly is mind-boggling! It is a metabolic rebound that would definitely kill
other mammals due to rapid lactic acid buildup. It is a 100% lethal condition
in other mammals. Dr. Nicola Quick (Duke University) confessed…
"We didn’t believe it at first... It goes against what we think mammals should be able to do".
How do they defy physiological limits? These whales are truly
physiological marvels. Cuvier’s are masterpieces of evolutionary engineering.
Streamlined bodies, foldable ribcages and prominent spleens/livers aid with
deep dives by managing oxygen and pressure.
From wolves to abyssal hunters – Evolutionary wizardry
These whales are living paradoxes in real life. They have a
lot of interesting features that distinguish them apart from other mammals and
whales.
Taxonomy – Belonging to the Ziphiidae family,
Cuvier’s beaked whale is the sole member of it’s genus called Ziphius. The Ziphiidae
family is the most species‑rich branch of toothed whales. Yet Cuvier’s stands
alone as the sole extant (living) species in the genus. It’s lineage stretches
back to the Pliocene epoch with adaptations uniquely tailored for life in the
abyss. That would be roughly 5 million years ago from today as indicated by
bone morphology and deep-sea adaptations. Fossilised remains unearthed from
Pliocene sediments (c. 5 million years ago), reveal that early Ziphius had
already possessed shortened rostra and robust skulls adapted for crushing deep‑sea
prey. It slowly evolved all the weapons in it’s arsenal which it has today. Over
epochs, natural selection sculpted their ‘goose‑bill’ beak and that compact
muscular body which became perfect for slicing through cold crushing waters. The
feature is also the one that earned it the quaint nickname as ‘goose‑beaked
whale’.
 |
| The skull of a Cuvier's on display |
Appearance – Their appearance and size are champion sized.
Their average length is about 15 – 23 feet or 4.5 – 7 metres. They weigh up to ~3100
kilograms or 6800 pounds. Their lifespan ranges approximately around 60 years
according to the website fisheries.noaa.gov. Their colouration ranges from reddish-brown
to slate grey. The hue comes partly from symbiotic algae blooming on their
skin. Depending on how many algae live on their skin, their skin displays a
range of colour spectrum. Sometimes they even appear yellowish!
Beak v/s teeth – Males wield a pair of small
tusk-like teeth on their lower jaw. The make is much like that of carnivorous
land animals. But those tusk-like teeth are remnants of an evolutionary past
and now used for social skirmishes rather than feeding. Despite the name ‘beaked’,
they suck prey into their toothless jaws like a cosmic hoover. Tusks? Purely
ornamental. Isn’t that crazy? Males’ two protruding teeth are useless for
feeding and have evolved solely for combat. Scarring patterns reveal ritualised
jousting over mates which is a behaviour documented via drone footage off
Hawaii in the year 2023.
Multi-chambered stomach – Now about stomachs. They
have not one, not three but a total of 9 chambers. Their nine-chambered stomachs
is a digestive labyrinth perfectly adapted for deep-sea squid, with vestigial
sections hinting at herbivorous ancestry. It is a relic from land-dwelling
ancestors. Yes, they evolved from wolf-like creature called Pakicetus. Descended
from Pakicetus (some 50 million years ago), they still retain bizarre
terrestrial relics.
 |
| A Cuvier's taking that brief quick breath before diving back into the deep |
Mitochondrial freaks – Unique mutations in energy-producing genes have made extreme anaerobic respiration become possible in their respiratory system. The mitochondrial mutations assist in tolerating lactic acid levels that would seize other mammals’ muscles. These whales carry molecular signatures of mutations in genes that govern oxygen storage and pressure tolerance. These are features that distinguish them even from their closest beaked‑whale cousins.
‘The Bends’ paradox – Despite these
adaptations, mass strandings linked to naval sonar show bubbles in their brains
and livers. It is only the proof that panicked ascents cause fatal
decompression sickness. In the 2000-year’s Bahamas stranding, 9 Cuvier’s died
after US Navy sonar exercises. It drove the whales ashore for some reason of
sheer panic. And then, identical events followed in the Canaries (2004) and
Spain (2024) too. They seem to be a well-evolved unit of a mammal and creatures
of the deep but somehow were getting stranded far from their favourite depths.
How Cuvier’s dives dwarf other giants
This comparison will tell you how incredibly powerful the Cuvier’s
beaked whale is cut out for deep dives against their fellow deep-sea creatures.
Their deepest record is 2,992 metres with a breath-hold of 222 minutes and a
recovery time at surface of under 2 minutes.
The deepest record for a Sperm Whale’s dive is 2,000 metres with
a breath-hold of 117 minutes and a recovery time at surface of 10 - 15 minutes.
The deepest record of dive for an Elephant Seal is 2,388 metres with a
breath-hold of 120 minutes and a recovery time at surface of 20-30 minutes.
Hunting in darkness, healing in silence – Life in the abyss
Total darkness begins from a depth below a kilometre onwards.
Cuvier’s beaked whales have to forage in absolute darkness where sun’s light
has never reached in the history of oceans. These depths are full of hills,
large predators, rocks, valleys, unpredictable currents etc. To navigate
through these lightless nightmares, the whale uses certain evolution-blessed
tools.
Diet composition – Analysis shows up to 98% of their diet is squid and some deep-sea fish including both bathypelagic and mesopelagic species. Giant squid beaks are frequently discovered among digested remains. Occasional fish bones suggest of opportunistic feeding on bathypelagic fish. Every dive is a calculated gamble where the deeper you go, the longer you can forage but the greater would be the recovery cost. Feeding primarily on deep-sea fish and squid is their major diet along with other minor unfortunate creatures in the mix.
Suction feeding – They expand their throat and suck the prey in. Just like a vacuum cleaner. This technique is efficient in the pitch-black depths of deep oceans. Expandable throat grooves create negative pressure to suck in prey. Although they have teeth and tusks, they are unable to chew or tear food into pieces. Hence, they have to swallow their prey whole.
 |
| Pic credit - ORCA, Ireland |
Echolocation – Cuvier’s inhabit a world devoid of
light so they engage in hunting fish and squid at depths exceeding 1,450 metres
using echolocation clicks. They use clicks to navigate and hunt beginning from
200 metres downwards. High‑frequency echolocation clicks, emitted only below
~200 m, bounce off squids and enable precise hunting in the inky blackness. They
always clicking deep underwater. But surprisingly, they remain silent near the
surface. It likely helps them in avoiding predators like orcas or sharks who
thrive on the surface. They reach a maximum growth length of 7 metres which is not
that big compared to their cousins and sharks. They don’t want to be bait by alerting
them with echolocation which can be traced by those predators. These predatory
sharks and whales literally listen in the dark by mapping prey with acoustic
pulses.
Hunting in pods – Socially, they are enigmatic
animals. They work in pods too so everyone gets a chance to be fed. Pods of 2 -
7 individuals communicate via clicks. Even though they cooperate for food, all
bets are off during the mating season. Males bear the scars of tusk-battles
against rivals over mates. As Dr. Grgur Pleslić (Blue World Institute) notes…
“Studying them is equal parts wonder and frustration...most of our fieldwork is waiting for them to resurface”.
Digestion – Their nine-chambered stomachs (discovered
in related spade-toothed whales) process cephalopods whole. Due to these
chambers, their digestion is quite efficient. Astonishingly, they surface from
epic dives needing barely 20 minutes of recovery. One tagged whale dove for 78
minutes and then resumed deep diving after just 4 hours of shallow dives. Their
incredible digestion and metabolism contribute to such efficiency.
Voice of the experts
“These guys blow our expectations!”
…says Nicola Quick who is a behavioural ecologist and helped document the 222‑minute immersion. Yet even experts suspect the record-breaking dives may be extraordinary responses and not natural reasons…possibly to naval sonar exposure. Yes it is thought to be so and observed too.
 |
| Dr. Nicola Quick | Pic credit - adbn.ac.uk |
Dr. Nicola Quick
was also a lead author of the 2020 JEB paper. In it, she wrote the following…
“It really did surprise us that these animals are able to go so far beyond what predictions suggest their diving limits should be”.
Dr. Erin Falcone who was an early dive pioneer in studying
these animals, said…
“When I first saw the data, I thought ‘is there any limit to what this animal can do?’”
Death by mimicry and the plastic plague – Controversies
There is a tragedy looming over these amazing whales and
guess who is responsible? Humans. Cuvier’s acoustic superpowers make them
catastrophically vulnerable to human noise. In other words, our eardrum shattering
sonar technology is hurting them. Military mid-frequency sonar triggers panic
which ends up causing whales to surface too rapidly. This is dangerous. The
result? Decompression sickness, haemorrhaging and mass strandings. If you
didn’t know, sonar pulses are extremely loud and could rupture your eardrums if
you were diving underwater. These sounds are powerful which go all the way down
to the sea floor and return back to the sender.
Once the whales (and not just Cuvier’s) panic, they lose
control over their vital functions from fright. Resurfacing for any animal
suddenly is dangerous and lethal. One has to eventually and slowly resurface by
taking a lot of time for it in order to not jeopardise internal organs.
Underwater pressure is incredibly great and recovery from it is not immediately
possible. It needs a lot of time. Sonar mapping and sonar usage have caused so
many casualties and disrupted the normal life of Cuvier’s beaked whales since
the past few years.
 |
| This beached Cuvier's was alive for some time after discovery | Pic credit - CBC News, Canada |
Bahamas, 2000 – More than 10 beaked whales were stranded
on the shore after US Navy drills in the Bahamas waters. 9 of these stranded
whales unfortunately died. Upon investigation, more and more evidence show up
as use of sonar work around it’s waters is pushing marine life onto the shores.
Canary Islands, 2004 – NATO’s sonar activities in the
sea are regularly linked to multiple Cuvier’s deaths. 14 strandings hours after
NATO drills were spotted. Autopsies on these whale carcasses revealed that they
had died from brain haemorrhaging. Mass strandings were clearly linked to naval
sonar with stranding events near the Bahamas, Canary Islands and Mediterranean
waters.
Almería, Spain, 2024 – A live-stranded Cuvier’s dies
despite rescue efforts – necropsy pending. This is recent news. But noise
pollution is being suspected as the driving factor for it’s resurface and
stranding. No other reasons explain why a whale came on shore in the area. Dr.
Lindy Weilgart (OceanCare) warns…
“These strandings are the visible tip of an iceberg...chronic noise disrupts feeding and communication, starving populations silently”.
 |
| A Cuvier's stranded in Almeria, Spain | Pic credit - OceanCare |
Navies now face pressure to adopt ‘quiet hours’ and
exclusion zones like the 50-nautical-mile ban around the Canaries that has
successfully halted strandings there. Necropsy shows bubbles in the livers of
Spanish whales show classic decompression sickness. The culprit? Military sonar.
Crete, 2022 – Cuvier’s populations declined by 67% in
sonar-testing zones in the waters of Crete Island. Unfortunately, it’s too late
to do anything since military activity is rampant in the region and Greece
isn’t doing much about it.
Mass stranding and mortality – Repeated evidence of
these amazing whales can be observed worldwide and not just in the waters of
the 4 countries above. Almost everywhere, the case is the same. Strandings
coincide with naval sonar exercises in the seas of Bahamas, Canary Islands,
Greece, Mariana Archipelago, etc. Unique traits can be observed on these dead
whales which die after being stranded ashore. Decompression-like gas-bubble
lesions in the stranded whales can be observed during necropsy.
Sensitivity to high-frequency noise – Behaviours of
the Cuvier’s seem disrupted and their deep dives are prolonged post-sonar
exposure. Unfortunately, they are feeling attacked by man’s interference in
deep waters. Mid-frequency (4.5 - 5.5 kHz) pulses can disorient whales and
trigger panic which make them ascend for safety due to intense fear. The rapid
ascent can cause risks from underwater surfacing to multiply very fast. Gases
trapped in tissues expand like shaken champagne and causes embolisms. These conditions
are lethal without being offset immediately and ‘immediately’ is an
impossible demand here. Dr. Isla McEwan (SMRU, St. Andrews) explains…
"It’s not malice. Navies simply didn’t grasp that our noise shreds their acoustic world. Imagine trying to chat over a jet engine".
Conservation – There is a conservation effort Classified
as “Least Concern”. It is trying hard and struggling to enforce conservation
rules. The Cuvier’s environment still remains under threat from fishing nets, naval
presence, ocean noise, trawling, vessel strikes etc.
Legal shields – Legal breakthroughs were put into
action by the year 2023. Under EU pressure, the Royal Navy trials ‘whale-safe’
sonar with 30% lower frequencies. The reduction seems to be working but more
studies are needed directly on the subjects to identify any ill effects. Cuvier’s
are now protected under MMPA (US), CITES Appendix II and regional agreements
like ASCOBANS and ACCOBAMS. For details on these laws, check out this link of
NOAA – fisheries.noaa.gov
Behavioural issues – A 2017 Californian study (Royal
Society Open Science) found sonar exposure led to alterations in their
behaviour like diving into unusual deeper depths, longer dive times and reduced
feeding time. These are peculiar behavioural changes in the species when
compared to past patterns. This trend is particularly observed after unexpected
helicopter sonar activities. If that wasn’t enough, there is more. Canadian
research off Newfoundland during NATO exercise CUTLASS FURY in the year 2016,
witnessed whales ceasing echolocation and foraging entirely during sonar events.
Meaning they weren’t even communicating with one another, foraging or showing
signs of living a normal life.
Plastic – If you were planning to accuse only sonar
for human activities, you must pause because there are more reasons. Beyond
sonar, Cuvier’s face a gauntlet of threats from humans and others out there in
the open wild. One of them is plastic pollution. More humans may have reached
the moon than the deepest point in the ocean called Mariana’s Trench but
plastic has made it there. As suction feeders, Cuvier’s inhale prey at 150 kPa
vacuum pressure. They have been tragically engulfing plastic debris by mistaking
them for squid. Suction-feeding whales ingest plastic bags because of it. In
the currents of the deep waters, plastic ends up mimicking like squids. You
know how plastic bags behave in underwater. They look like certain squids which
the Cuvier’s mistake and end up sucking in which goes on to cause fatal
blockages and killing them. Autopsies by Sicily Coastguard Lad and other agents
have discovered plastic in necropsied Cuvier’s calves. Inside one of such
whales, 4 kgs of debris like fishing nets, items from trawling that looked like
fish especially toy squids from trawling discards and plastic bags were found.
To the underwater animals, these synthetic items look much like edible fish or squid.
Microplastics – were also seen embedded in the
intestinal lining of these innocent calves. Microplastics are everywhere in our
environment by now both in our air and in our waters. They are even making into
our diet which is alarming. Tackling microplastics will be a major challenge in
the coming decades. These tiny plastics are not even detectable or visible
without equipment and they are easily carried across the world by air and water.
Fish consume them and then make it into the system of those who consume them. They
have even managed to infiltrate the bodies of deep ocean creatures. 2024 studies
found polystyrene particles embedded in kidney tissues of Cuvier’s beaked
whales. They ended up causing systemic inflammation and taking their lives
away. These poor whales ended up being confused between satiation and starvation.
Stomachs distended by plastic falsely signal that they have been fed or are full.
It only worsens for them and are led to emaciation. A calf stranded in Sicily
had 80% of it’s stomach volume occupied by a single plastic sheet. What a
terrible suffering it must have undergone prior to exiting this world!
 |
| The incredibly tiny microplastics |
Bycatch – …or trawling nets are a threat to all
aquatic life of the ocean floor. Trawling is targeted at fishing only 1 or few
species of fish and for which, entire ecosystem of aquatic species is
destroyed. When trapped by bycatch nets, they have no way to escape. Unlike
fish that don’t need to resurface, these whales need to resurface to breathe
air. Drift nets unfortunately, drown them from California to Indonesia. There
is no escape from these nets and not even for anyone in the vastness of oceans.
Trawling lines are so large than they can be seen from low-orbit satellites in
space.
Climate change – Warming oceans may shift squid
distributions which will end up starving populations of Cuvier’s beaked whales.
Squids don’t dive to the depths like whales and so hot waters will drive them
away to colder waters which will leave Cuvier’s without diet. In fact, the
effects of climate change in waters affect all underwater creatures in every
possible way. Climate change and global warming are not good for life.
Their reproduction is agonisingly slow – Females give
birth to one calf every 2 - 3 years after a 12-month gestation period. This is
very slow for such a small creature making it very menacing to go into deep
dives. With incredible underwater pressure and warming waters in the surface,
pregnant female Cuvier’s might find it challenging to dive into the colder
waters of the deep ocean. With lifespans up to 60 years, each adult lost is truly
a generational blow.
Military sonar – Once thought to be harmless from a
distance, has been repeatedly implicated in mass stranding cases of Cuvier’s
beaked whales. They have proven to be really dangerous over time. A landmark
2011 – 13 Southern California study tagged 16 individual Cuvier’s and
correlated dive patterns with 2 sonar types namely high‑power ship‑based and
mid‑power helicopter‑deployed MFAS. Certain effects were immediately obvious
from the whales’ point of view. During sonar use, whales extended both deep and
shallow dives and surface intervals lengthened by up to 50 % when within 50 km
of mid‑power sonar engagement. It looked as if their entire discipline was altered
upon exercising military sonar. These changes disrupted their foraging rhythms,
increased energetic stress and reduced feeding success. Clearly, their lives
were getting affected from the use of military sonar.
“Variability among individuals suggests personality or stress history plays a role. Some whales seem to ‘tough it out’ while others surface early, perhaps startled by noise”.
…notes Dr Nicola Quick.
Stranding tragedies – Wash‑ups in the Bahamas, Canary
Islands and the Mediterranean often coincide with naval exercises as mentioned
earlier. Post‑mortems reveal gas‑bubble lesions akin to human ‘bends’
suggesting rapid stress‑induced ascents from sonar panic. These tragic
unnecessary panics cause them immense fear and flight mode kicks in to get away
from the source of sonar. Sonar is one of the most ear-deafening noises that we
have managed to invent. The whales not only rush to the surface but as they
flee from the repeatedly beeping source of sonar, they run aground or get beached.
It is not going to be a nice plain beach everywhere. They get wedged into
places on the shore where it becomes impossible to make it back into waters
after the panic has gone. When mid‑frequency pings echo in the deep, it seems
whales almost always alter their dive profiles fatally. Cuvier’s navigate via
echolocation clicks at 5 - 25 kHz. These frequencies get directly overlapped by
military mid-frequency sonar (4.5 - 5.5 kHz). When bombarded by this powerful noise,
whales abort hunts and surface chaotically which ends up causing nitrogen
bubbles in the blood circulation to expand like shaken champagne. Stranded
individuals show brain lesions, haemorrhaged ears and ocular bleeding (e.g. –
the 1996 Greece stranding) which are effects of direct sonar impact.
Mediterranean populations near sonar zones declined 67% between the decades 2010
- 2022.
Science’s race to understand
In October of the year 2023, a landmark project was launched
in the Adriatic Sea. It was the first satellite tagging of Mediterranean
Cuvier’s beaked whales. By tagging these whales, newer findings could be made on
their behavioural patterns and habits. Using a catamaran and cross-border
collaboration, teams from Croatia and Italy deployed tags to track movements
and the dive profiles of these whales. Since then, few whales have been tagged
and are being studied today. Dr. Massimiliano Rosso (CIMA Foundation) called it
‘a game-changer for protecting these ghosts’. DTAGs and satellite-linked
tags record behaviour, depth and sound. The tech helps in revealing acoustic
foraging signatures and dive patterns.
Meanwhile, the July 2024 stranding of a spade-toothed whale
(a Cuvier’s cousin) in New Zealand offered rare dissection insights. This was
on the other side of the Earth. Anton van Helden, who named the species,
emotionally noted that…
“I can’t tell you how extraordinary it is...we found nine stomachs and vestigial teeth!”
Such data reveals evolutionary clues to their deep-diving
prowess. Advances in marine bio‑logging deliver unprecedented insight. What some
of these technologies can offer us is listed below.
- Stable isotope analysis work helps reconstruct diet and foraging depth and not simply by sight but via chemistry. We can accurately tell their diet and what they are eating. Chemical “fingerprints” in whale tissues reconstruct long‑term diet and habitat use because you are what you eat – at even atomic levels.
- Satellite‑Linked Tags (SPLASH10‑F) will record depth, locations and temperatures for weeks. This will instruct and reveal their long‑term patterns to the scientists.
- DTAGs
are suction‑cup devices that latch onto the whales. They keep capturing 3D
movement, acoustic environments, mapping echolocation clicks and sonar
exposures. These are important to be discovered and used in interpretation
to the military so that they can avoid unintentionally harming critical
species of our seas.
Together, these tools paint a dynamically detailed portrait
of the deep seas. We can get to find out dive by dive, whale by whale in the
open seas much better than our traditional techniques.
Why the abyss needs ambassadors
Understanding Cuvier’s beaked whales is very important for
us. We are the only animals in nature that can enact significant conservation
of other species. Studying these whales transcends mere curiosity and
contributes much to assist in their preservation. These gentle giants beckon us
to redefine our relationship with the ocean’s final frontier. They are not mere
record-breakers but even greater than that. They are bioindicators of ocean
health. As Dr. Enric Sala (NatGeo) puts it…
"If the deep is Earth’s last wilderness, Cuvier’s are it’s canaries. Their decline is a scream from the abyss we cannot ignore”.
Why the abyss needs ambassadors? For all the below reasons
primarily.
 |
| A Cuvier's beached in Cyprus | Source - medaces |
Illuminates extreme physiological adaptations, potentially guiding aerospace and medical innovation. We need to know what these whales are really made of and how they adapt to the tough conditions of the deep oceans. By forging their physiology and successfully mimicking what evolution gifted them, we can add progress to our technology and rocket mankind into the future.
Reveals how human noise pollution disrupts marine life on an unprecedented scale. Besides plastic and sonar, we might unknowingly be harming them with other technology. Hence, it is important that we need to know all possible threats against them whether artificial or natural.
Sparks public fascination with ‘hidden giants’ of our oceans and thereby breeding conservation support. Conservation efforts need more hands and it can only come from the fascination to discover more. Instigating public passion requires us to study them intently and come up with more data. Their superhuman dives which are over 3 hours in complete darkness sparks conservation spirit and wonder. Imagine viral headlines like ‘Whale Holds Breath Longer Than Most Films Run Time!’ They capture imaginations and galvanise conservation action. These whales can truly inspire the general public.
Biomedical insight from these whales about their amazing anatomy is important in all our researches back on land. Their metabolic control, oxygen management and pressure resistance could influence our researches from anaesthesia to space travel. Their oxygen management and pressure tolerance inform human medicine. All of these are important parameters for us to know especially for protection against deep-sea diving injuries and manned space travel.
These beautiful whales are bioacoustics sentinels. They highlight the disruptive impacts of human-generated noise — even in the deepest ocean trenches. They will tell us how our far-reaching technology is affecting even other species underwater just like it does to them. As ‘canaries of the deep’, their sonar headaches signal broader marine health risks, prompting noise regulations and quieter ship designs.
They are our best bio-indicators of oceanic health. Their dives map oxygen-minimum zones expanding due to climate change while their strandings expose pollution crises.
As Dr. Sascha Hooker (St. Andrews University) firmly asserts…
"Their collapse would be a canary-in-the-coal-mine for the deep’s unseen apocalypse".
Conservation efforts and the future
The road ahead is both hopeful and fraught with the unknown.
There is no telling but it seems to be getting better than the past many years.
Though classified as ‘Least Concern’ by the IUCN, Cuvier’s beaked whales
still face stealthy threats. But conservation works are active across the world
now and things are mapping out nicely.
Mitigation approaches – Naval sonar usage near key
whale habitats is under closer scrutiny and there are activists urging for regulated
quiet zones. Adjusting naval schedules, deploying passive acoustic monitoring,
establishing sonar-free zones and responsive strategies are helping improve
conditions in the oceans. Noise litigations in recent years are showing that
Cuvier’s conservation is being taken seriously by countries. NGOs like Whale
and Dolphin Conservation won a 2023 lawsuit forcing NATO to disclose sonar
exercise schedules which is enabling real-time whale alerts for those concerned.
 |
| An AQS-13 dipping sonar being lowered into the waters from a helicopter |
Bycatch prevention – Fishing restrictions and gear
modifications may reduce accidental entanglement. Gear modifications like
ropeless traps and weak links on trawl nets aim to spare deep‑diving whales from
entanglements. Countries like the UK for example, has already activated bycatch
reduction policies. UK policies mandate cetacean bycatch monitoring from the
year 2025 while California trials LED-lit nets that reduce entanglement by a 70%.
You can also help by opting for sustainable seafood. Make your deep-sea dining
worthwhile for others too. For example, choose MSC-certified squid to reduce
bycatch from destructive trawling.
Citizen awareness – Every strand or video shared
helps keep pressure on regulators. Inspired viewers are often the fuel of
change. Public pressure can be amplified by viral videos of these wonderful
whales and talking about them more often. Such push has already driven partial
policy shifts. Yet full protection demands global coordination and enforcement.
With internet and social media, these efforts can be driven forward very
effectively.
International protections – Listed on CITES Appendix
II, IUCN (Least Concern) and covered by legislative pacts of ASCOBANS,
ACCOBAMS, MMPA etc.
 |
| Pic credit - The Forefront Mag |
Sonar moratoriums and zones – Canary Islands ban
began in the year 2004. You cannot use sonar there anymore. After the ban, mass
strandings have ceased very significantly. The Cuvier’s are living in peace
around the islands since the ban. Similar quiet zones are now proposed in the
Mediterranean and North Atlantic regions too.
Silent Oceans Campaign – The campaign aims at petitioning
governments for sonar regulation around the sea parts where whales live. Petition
for mandatory sonar buffer zones using WDC templates are always in demand and
the headlines due to the campaign.
Stranding Networks – The UK has taken up this
initiative whereby their citizens can involve in the government’s conservation
efforts. Citizens can report strandings via the UK Cetacean Strandings
Programme. It is important to report carcasses via the UK Cetacean Strandings
Programme in the UK because it is vital for necropsy data. More data will help
all parties involved in formulating strategies to reduce such incidents in the
UK waters.
Temporal restrictions – These restrictions are very
beneficial for the whales since they temporarily halt military exercises in sea
waters. The military will have to take a break during their passage. Limiting
naval activities during known whale breeding or migration seasons reduces risk
that the whales have to face. With less to no disturbances, it is obvious that
the whales could thrive.
Acoustic Monitoring Networks – Real‑time detection of
beaked‑whale signals can trigger sonar shutdowns from creating a responsive ‘smart
navy’ approach. These new systems are in place across the world to trace
the ultrasonic signals from whales would engage a suspension of all sonar
activities. It is best for both worlds that way.
Tagging triumphs – A June 2024 data from ‘Lyra’
(a Mediterranean female whale) has revealed dialect-specific clicks between
pods. It was likely the first time that such a discovery was made. Such
information is critical for mapping breeding populations. They help us in
planning activities in the water that do not affect them or are conducted
anywhere near their pods. Despite slow reproduction (1 calf every 2 - 3 years),
recent victories are offering much hope.
Recent discoveries from the year 2024
A Duke University study in the year 2019 had tagged whales
off Cape Hatteras and capturing nearly 6,000 dives by the year 2024. They found
the whales engaging in regular deep dives (~1,600 m) with short breaks.
However, their recovery times after such long dives were pretty inconsistent.
This suggested significant individual variation. Biopsies even revealed
collagen structures in their blubber acting like spring-loaded depth gauges. It
is unusual. They were rebounding from compression 5x faster than Sperm
whales.
Also were threats and their impacts on these beautiful
whales discovered. The major threats that these whales faced by 2024 were
bycatch pingers, climate shift and noise pollution. In the Pacific ocean alone,
bycatch fishing resulted in the deaths of atleast 200 Cuvier’s every year upto
2024. The mitigation progress was monitored less than 10% by fisheries bodies.
Climate shift is causing squids to move towards the poles where the waters are not
warm and whales are left to starve. There is no immediate solution at all for
this. Noise pollution is causing them to have chronic stress and atleast 90% of
their foraging activities have been observed as reduced. To mitigate this,
there has to be partial sonar bans across the entire European Union territorial
waters.
Hope on the horizon?
The following log is from the Adriatic Sea by CIMA Research
Vessel in June 2024.
“We’ve tagged "Lyra" – a 5m female. Her GPS data is revolutionary.
- Daily routine – 3 epic dives >2,000m + 40 "micro-dives" at 300m.
- Recovery – Only 17 minutes between dives vs. 120 mins for elephant seals.
- Social clicks – Recordings show distinct dialects between Mediterranean/Ionian pods”.
The good news is that conservation efforts are really
working ever since the troubles of Cuvier’s were identified. A lot of progress
has been accomplished by the year 2025. Two of the major conservation wins are listed
below.
 |
| From one of the locations in Azores Marine Sanctuary |
✅ Azores Marine Sanctuary – Post-2023,
the EU enforced 50-nautical-mile sonar exclusion zones around critical habitats
like the Azores. As of the year 2023, 150,000km² sanctuary has been officially
formed. Meaning, there is zero sonar activity in this much of space.
✅ UK Bycatch Policy – Mandatory
cetacean bycatch monitoring from 2025. You cannot trawl in the UK waters like
you used to do earlier. New laws and policies are in place against illegal
trawling. However, there are conditions and procedures enacted by law to do
that. The Royal Navy now trials 30% lower-frequency ‘whale-safe’ sonar
though global coverage remains patchy.
Such candid insights illuminate not just data but the
ethical responsibility and scientific wonder behind each deployment. The abyss
has champions but they need voices at the surface.
The ocean’s ultimate endurance artists
As the sun sets over the Adriatic, researchers aboard the
Coolway catamaran scan the waves. They are busy monitoring our fellow mammals
of the deep ocean. A faint blow appears and then a Cuvier’s surfaces, exhales
and dips back into oblivion. Then, it might be up to the researchers of the
next shift to monitor them. For the next three hours, the whale will hunt in a
realm darker than space and under pressures that would liquefy steel before
resurfacing for the next breath.
“They are ambassadors reminding us that miracles exist in the unexplored”.
…muses Dr. Draško Holcer (Croatian Natural History Museum).
In a world obsessed with noise and speed, the Cuvier’s beaked whale is a
masterclass in patience, resilience and silent strength. They mind their own
business even when the males are warring with each other. Protecting them isn’t
just conservation but reverence for life’s most astonishing extremes. Cuvier’s
beaked whales remind us that the ocean still harbours wildest extremes and that
our activities echo into it’s deepest trenches.
In protecting their world by curbing sonar, expanding
acoustic sanctuaries and refining fishing practices, we ensure that these
marvels can continue their silent record‑shattering journeys. By doing so, we
not only preserve a species but safeguard the health and wonder of Earth’s vast
and unseen wilderness. Choose sustainable seafood to reduce bycatch, join beach
clean-ups whenever you can and support ocean noise regulation campaigns.
Fascinating bits
Facial art? Males often sport mating scars from tusk jousts.
Mating and tusk scars on the male whales speak of fierce dominance battles in
the deep ocean floors.
Algal skin coatings can make them look yellow which is a
natural oceanic accessory. They are algae tinted warriors. Sea-skin art
courtesy of algae?
They have strong group dynamics. They dive in small pods
though. Pods coordinate dives which is possibly for hunting, safety, sharing
hunting intelligence or sonar camouflage.
They are shy little devils. They surface briefly for just ~2
minutes before plunging into the inky blackness again.
A Cuvier’s 222-minute dive outlasts The Return of the King
(201 mins) movie. In a cinema versus dive, this whale outdid the production. It
is a cinematic shame for Avatar: The Way of Water which runs for 192 minutes. Their
3-hour and 42-minute dive even beats the Titanic movie whose duration is 3
hours and 14 minutes. James Cameron wishes that he didn’t get a cinema snub
from a co-mammal.
Algae couture can become a nuisance as they age. Older males
turn ginger or reddish-brown which is not from ageing but algae infestations.
Sometimes it looks like algae armour or rust. Unfortunately, they are symbiotic
algae colonising their scar tissues.
Tooth truth is that the male teeth or tusk are really useless for eating. Males wield two conical teeth as tusks which are not for eating but meant to fight for mates.
Cuvier’s whales are geriatric warriors too. They live to 60+
years. The females menopause by age 40 and still continues leading dives. They
incredibly keep surviving decades after menopause.
Last thoughts
Cuvier’s beaked whales are nature’s proof that life can
stretch far beyond human imagination. There will always be something astounding
for us out there. Their breath-hold records redefine what a mammal can do
beneath crushing pressure and near-freezing gloom. It is only something that we
can only dream of doing. Yet, that superpower may also highlight their
vulnerability since human hustle and sonar only push them to extremes. By
studying them, we get a glimpse of both a cautionary tale and evolutionary
genius for conservation.
 |
| You can see their 2 tiny tusks on the lips and also the extensive scratches on their skin incurred from fighting for mating rights |
Cuvier’s beaked whale embodies a paradox as the deepest
diver, yet most vulnerable to human noise. Share this post, spread the wonder and
next time you hear a sonar ping in the news, remember that under the surface,
giants are holding their breath. Let this also be a call to action for
continued research, quieter navy zones and sustainable fisheries. Because no
creature should have to out-perform physics just to survive in our noisy seas.
References and suggested reading
Statistical dive records & Guinness recognition (en.wikipedia.org, livescience.com,
reddit.com)
J. Exp. Biol. (2020) extreme dive limits paper (journals.biologists.com)
Canary Islands sonar-stranding history & policy (en.wikipedia.org)
RSOxygen whale sonar forgaging disruption (2017) (axios.com)
NATO sonar strandings & Nature reports (nature.com)
Mariana Archipelago sonar–strandings link
An Expedition Log by Dr. Alistair Finch, Marine Biologist –
Mediterranean Sea | 41°N, 18°E | 05:00 BST. Ending excerpt from her log…
“For real-time conservation alerts and satellite dive data, visit DeepSeaGuardians.org.uk. This is Dr. Finch – signing off to hunt coffee. Over”.
#cuvierbeakedwhales #marine #animal #mammal #whale #biology #science #anthropology #fact #sea #ocean #mediterranean #canaryislands #greece #italy #croatia #eu #europeanunion #uk #unitedkingdom #us #unitedstates #america #beach #sonar
0 Comments