so another video that's rather murdery well if that's your sort of thing you should definitely
consider checking out my podcast the casual criminalist which puts out two new episodes
every week from serial killers that haven't aged out of primary school yet just schizophrenic
breakdowns and bible obsessed sociopaths so i write a callum is combing through
the graveyards of history like an absolute weirdo and it's all in the name of giving you some great
crime content so if you're looking for a good true crime podcast that's casually done why
not give the casual criminalist to try there are links below and let's get into the video
sable island lies 300 kilometers off the coast of nova scotia canada near the edge
of the eastern continental shelf a windswept crescent-shaped sandbar 43 kilometers long
and barely one kilometer wide it has long been known as the graveyard of the atlantic with over
350 ships having founded on its shores since 1583. the treacherous waters around the island
prompted the establishment of a rescue station in 1801 which over the following 150 years saved
the lives of thousands of shipwrecked sailors today sable island hosts a weather station run
by the canadian government manned year-round by a small group of researchers an important wildlife
preserve the island is home to a population of 550 wild stable island horses descendants of livestock
released onto the island in the late 18th century and large breeding colonies of seabirds as well as
grey harp hooded ring and harbour seals but in 1993 sable island became the site of a gruesome
murder mystery prompting a decades-long hunt for the strange and elusive killer
in january 1993 canadian researcher zoe lucas was conducting regular patrols of the island's beaches
searching for oil covered birds and other signs of environmental damage when she stumbled across
a number of seal carcasses washed up on the beach the seals had been horribly mutilated with bizarre
corkscrew wounds spiraling head to tail the edges of the wounds were clean as if they had been cut
with a sharp instrument and cut right through the seal's skin and blubber while leaving the muscle
beneath untouched lucas had never seen anything quite like it while at first this gruesome
discovery seemed to be an isolated incident soon more and more carcasses began turning up by 1996
over 400 had been discovered on the island while by 2011 the total had reached over 4 thousand
meanwhile across the atlantic dead seals began washing ashore near norwich england saint andrew
scotland and strangeford log northern ireland all bearing the same distinctive corkscrew
wounds these discoveries corresponded with a sharp decline in the birth rates of grain harbor seals
the victims were nearly all young pups or pregnant mothers but what on earth could be inflicting such
strange injuries as in any good murder mystery zoe lucas began rounding up the usual suspects human
action pack ice boat propeller strikes and attacks by orcas but all these culprits were quickly ruled
out as a federally controlled territory access to sable island is strictly controlled making it
highly unlikely that human assailants could have snuck ashore and mutilated the seals pack ice also
does not form within 200 kilometers of stable island and most of the harbor sealed deaths had
occurred in june and july while at first chip propellers appeared to be the most plausible
culprit the corkscrew wounds brought little resemblance to the propeller strike injuries found
on other sea creatures like manatees nor did they resemble injuries from entanglements in fishing
lines or nets furthermore many of the seals were still warm or even alive when discovered
indicating that they had been attacked just offshore in water too shallow for most ships to
travel finally attacks by orcas were ruled out as the wounds were inconsistent with the tooth shape
and hunting behavior of those particular predators lucas quickly found herself back at square one
but soon two tantalizing pieces of evidence turned up the first was the carcass of a seal which had
been fitted with a time depth monitor as part of an environmental study to lucas's surprise the
corkscrew wound ran beneath the webbing used to secure the monitor to the seal's skin but
the webbing itself had not been damaged this seemed to indicate that the skin and blubber
had not been sliced but rather torn the second piece of evidence was the fact that while 98 of
the examined carcasses exhibited the distinctive corkscrew wounds a small fraction bore markedly
different injuries such as missing heads and flippers linear slash marks and crescent-shaped
bites to lucas this could mean only one thing the seals were the victims of a shark attack but what
kind of shark well to find out lucas wrote letters to shark experts in south africa australia and
california in closing photos of the unusual spiral wounds one of the experts she contacted had ever
seen anything like it in 2002 lisa natanzan a scientist with the united states is national
oceanographic and atmospheric administration apex predators program agreed to help lucas
track down the culprit nattinson drew up a list of six large shark species commonly found in the
waters off sable island but once again the peculiar circumstances of the seal slayings
seemed to rule out most of them the blunt-nosed six-gill shark and the tiger shark had only ever
been reported in the area as juveniles and these were too small to prey upon adult seals ditto
for the blue shark while the needle-like teeth of the short fin mako shark did not match the spiral
wounds the great white shark was known to frequent the area and was likely responsible for at least
some of the killings but this did not account for the large number of grey-sealed deaths in january
and february when the waters of sable island are too cold for great whites this left only one
highly unusual candidate the greenland shark the greenland shark is a mysterious and elusive
creature a member of the insomniocedile or sleeper sharks they typically inhabit the cold dark depths
of the arctic ocean where the temperature rarely rises above freezing as a result the greenland
shark lives life in the slow lane with one of the slowest metabolisms of any shark this in
turn gives it exceptional longevity with certain individuals estimated to have lived for nearly 500
years the greenland shark is a generalist predator and scavenger feeding on a variety of sea life
like fish squid crabs jellyfish and the carcasses of any land animals that happen to sink to the sea
floor indeed one specimen was discovered with an entire reindeer in its stomach strangely nearly
all greenland sharks are infected with a type of crustacean called a coke pod which anchors itself
in the corner of the shark's eyes effectively rendering them blind at first glance the greenland
shark's slow scavenging lifestyle would seem to make it an unlikely culprit and the saber island
seal killings but the closer lucas and nattinson looked the more the facts seemed to fit together
while commonly associated with arctic waters greenland sharks actually migrate widely and have
been found as far south as north carolina indeed they are known to frequent the waters around
sable island in the winter and even to come into shallower waters to feed while at first it seemed
unlikely that such a slow-moving shark could catch a fast and agile seal lucas and natinson
speculated that the greenland sharks hunted by ambush attacking inexperienced pups in murky water
or while they were sleeping but the key piece of evidence was the shark's particular anatomy
and feeding style the teeth of the greenland shark differ dramatically between its upper and
lower jaw with the upper teeth being needle-like for gripping and the lower teeth blade-like for
slicing though capable of brief bursts of speed when ambushing fast prey the greenland typically
feeds by suction quickly opening its buckle cavity to draw the prey into its mouth with the prey
firmly clamped in its jaws the shark then shakes its end violently side to side to further slice
a tarp before swallowing it according to lucas and nattinson this combination of gripping and
shaking would cause the seal's skin and blubber to split and tear the unusual corkscrew pattern being
accounted for by two factors first the collagen fibers in the seal's skin wind around its body in
a spiral fashion and it is along these lines that the skin splits and second a seal's instinctive
reaction when grabbed is to spin around its body axis in a bit to free itself a reflex which
ironically worsens the damage inflicted lucas and nattinson's findings published in 2010 were picked
up by dozens of scientific journals and formed the basis of a national geographic documentary
on the case the pair were widely celebrated having finally solved the mystery of the corkscrew killer
but had they according to geoffrey gallant of the sun lawrence shark observatory lucas
and nattinson's theory just doesn't add up firstly most of the seal carcasses found in the
uk washed up in july when the waters around the british isles are a full 20 degrees warmer than
greenland sharks typically prefer making them unlikely culprits in those killings
secondly the greenland shark theory failed to account for the sudden appearance of the corkscrew
corpses which had never been reported prior to 1993. but most damningly the seals injuries
were entirely inconsistent with greenland shark behavior as gallant explains there is no doubt
that the greenland shark does occasionally predate live seals however the victim would probably be an
inexperienced pup or be asleep distracted asleep injured in an ice hole or the visibility would
have to be so poor as to offer the seal no warning of the incoming shark's presence the greenland
shark is much more likely to feed on an already dead seal which requires no energy output and
that offers no risk of injury for even small seals have sizable teeth with which to defend themselves
furthermore photoanalysis reveals that many seal carcasses found with the corkscrew wound appear
otherwise intact no parts are missing it makes no sense whatsoever for a greenland shark to
needlessly expend the fuel it needs to survive if it isn't going to feed so if not sharks then
what else could have inflicted such strange spiral wounds this was the question plaguing
david thompson of the saint andrews university marine mammal research unit in scotland one of
the first researchers to investigate the uk seal carcasses like lucas and natinson at first thomas
dismissed boat propellers as the culprit as the seal's wounds did not match known boat
strike injuries but one day it occurred to him that if some structure held the seals against a
propeller it would create a corkscrew-shaped wound instead of the typical series of straight gashes
and as luck would have it certain ships featured just a structure known as positional thrusters or
court nozzles these devices consist of a propeller housed in a short swiveling duct they're typically
found on tugboats oil rigs and drill ships and are used to maintain the vessel's position over the
sea floor unlike a regular propeller positional thrusters are only operated intermittently
in short bursts meaning that an inquisitive seal could easily swim up into one only to be
sucked in when the propeller is activated pouring through shipping records for the areas where the
sealed carcasses were found thompson discovered that in nearly every case a vessel with positional
thrusters had been nearby experiments conducted by thompson's research assistant joseph honor through
seemed to confirm the theory honor through constructed small wax models of seals and fed
them into a scale model of a positional thruster the models emerged bearing the same corkscrew
wounds as the real seals cut at the same 35 degree angle these findings published at the same time as
lucas and natinson's prompted politicians to take action to prevent further seal deaths in april
2012 the uk government issued official advice to the shipping industry to avoid using positional
thrusters near seal conservation areas and during seal breeding season according to geoffrey gallant
thompson and honor freu's discovery turns the case of the sable island seals from a curious natural
mystery to a tragedy of environmental degradation human activity is yet again the likely cause for
these needless deaths who knows how many lifeless bodies didn't actually make it to shore life is
dangerous enough for seals without having to deal with giant underwater food processors if i were a
seal i'd choose the shark i would at least have a fighting chance to survive and if i were killed my
death would serve to sustain a fellow creature of the sea but just as the mystery appeared to
have been solved once again a new discovery came along and blew the case wide open in december
2014 amanda bishop a doctoral candidate at durham university in scotland was observing a colony of
grey seals on the isle of may when she witnessed a shocking incident as she watched a male seal
grabbed a newly weaned pub dragged it to a nearby freshwater pool and drowned it once the pup was
dead the male began tearing into it ripping up and eating pieces of skin and blubber such behavior
is common in many animals as a means of reducing genetic competition but what caught bishop's eye
was the manner in which the male seal attacked the pup's carcass as the male worked his way along the
pup's body the skin tore along the spiral collagen lines creating a distinctive corkscrew wound over
the following week bishop along with joseph honor through watched the male commit infants aside
three more times in every case inflicting wounds nearly identical to the sable island carcasses in
a 2016 paper bishop onofru and their colleagues posited that cannibalistic infanticide by male
seals and not sharks or positional thrusters was the true cause of the court's true deaths
as for why this kind of spiral wound had never been reported prior to 1993 the team speculated
that most seal colonies are located far from shore or on ice-making making carcasses unlikely to wash
up on inhabited beaches or that the wounds had previously been misattributed to other causes
like entanglement in fishing lines and nets in particular they pointed to an incident in 1998
where a large number of mutilated seal corpses washed up on the beaches of prince edward island
resulting in widespread speculation that they had been deliberately mutilated by fishermen
or sealers or become trapped and torn up by sea ice according to honor through the discovery of
infanticide among grey seals presents a valuable lesson in the power of preconception in science
i firmly believe that if grey seals had been witnessed attacking grey seal pups or harbor seals
killing them and creating corkscrew legions before any of these other seals had washed up nobody
would have thought of ship propellers however this discovery has done little to bring the case of the
corkscrew killer to a satisfying conclusion and many researchers remain convinced that the true
culprit is still greenland sharks or positional thrusters or even something completely different
like tidal turbines used to generate electricity some even argue that all four could be responsible
each accounting for a portion of the total deaths but one thing is certain when dealing with nature
nothing is ever as simple as it seems so i really hope you found that video interesting if you did
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