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Great White Shark in Oct 2004 at Guadalupe I., Mexico © Chris Hartzell (above, from a cage dive); another Great White Shark in June 1998 at Dyer I., South Africa © Dan Singer (below right) |
Great White Shark Carcharodon carcharias
is the largest of the dangerous sharks, with individuals recorded up to
6.4m (21 ft.) and 3175 km (7000 lbs). More typically, large adults are
3–5.5m (10-18 ft max). The Great White was, of course, the subject of
Peter Benchley's novel and the Steven Spielberg movie Jaws.
Many consider it to be the most feared predator on earth. [But not me
... I am much more afraid of large crocs and Polar Bears (see those
accounts). I would be willing to dive with Great Whites in clear water
outside a cage, except at my age, my diving days may be over.]
The
International Shark Attack File (ISAF) is cited by Carwardine (2002).
ISAF investigated 2154 unprovoked shark attacks and found that about
25% proved to be fatal. Great White Shark was by far the primary
species confirmed in the fatal attacks. The percentage of attacks
attributable to "White Death" has risen in recent years as more humans
have been using the shoreline ocean habitat used by Great Whites to
hunt their primary prey — pinnipeds (fur seals, elephant seals, sea
lions et al.). Most attacks on humans involve surfers, paddle-borders,
and others in wet suits on the surface who resemble seals when viewed
from below (Great Whites attack from below). Human fatalities would be
greater if Great Whites actually hunted people, but many attacks are
broken off by sharks when they determine that the prey is not a
pinniped. In truth, then, Great Whites are not true 'man-eaters' — they
do not view us primarily as meat. Instead, they mistake humans for
their actual prey.
Still — the image of a Great White
Shark headed for you in the water would be entirely terrifying (right).
They surely are an apex 'monster of god' in the 'jungles of our mind.'
This
means that many humans (like me) have a keen desire to encounter a
Great White in the wild, but safely. For those willing to get into
wet-suits and use SCUBA, cage diving has become a cottage industry at
various locales around the globe. Chris Hartzell took the dramatic
'at-sea' underwater shot from a cage off Guadalupe Is., in the Pacific
Ocean southwest of Baja California, Mexico [more details and photos on his website].
Cage diving is also offered at several sites near Cape Town, South
Africa, such as Dyer Is., where a colony of Southern Fur-Seal provide
prey for a population of Great Whites. Tourist boats are anchored near
the small island and bait is used to attract sharks. A decade ago it
was customary to suspend the bait slightly above the sea surface,
enticing sharks to lunge upward, mouth agape, as shown in Dan Singer's
photo (above right) from Dyer Is. in 1998. This practice — along with
the practice of pulling bait along the surface in hopes of having
sharks leap for bait at speed — has since been banned in South Africa
as unnatural and possibly detrimental to these sharks, which are
declining globally. More recently the baiting is simply floated on or
just below the ocean surface, but observers in the cages or remaining
on the boat still get very close to huge sharks that swim right next to
the boat (my photo from Dyer Is. in 2005 is below). |
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Great White Shark: July 2005 Dyer I., South Africa © Don Roberson (above) |
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Oceanic Whitetip Shark on 3 Nov 2003 Elphinstoe Reef, Red Sea, Egypt © Thomas Ehrensperger (below; permitted use via Wikipedia Commons) |
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Oceanic Whitetip Shark Carcharhinus longimanus is my choice for the second shark on my 'monsters of god' list. [Quammen (2004) had chosen Ganges Shark Glyphis gangeticus
as his second shark, but man-eating is unproven and unlikely in that
endangered species. I chose Mugger Crocodile as the substitute for
those Indian river systems. Here I chose a second shark as a substitute
for Puma Puma concolor.] Oceanic Whitetip is a competitive,
opportunistic predator, "rather than avoiding trouble in favor of a
potentially easier future meal;" Compagno (1984). It simply conserves
energy between infrequent feeding opportunities. "Once they have found
food, they can be very aggressive and will dominate other shark species
joining in the feast;" Carwardine (2002).
Oceanic
Whitetip is a large shark (it was once called "Lesser White" to link it
with Great White Shark) that can routinely reach about 3m (10 ft) long.
The largest was 3.9m (12.7 ft). It is an undoubted 'man-eater' and is
probably responsible for more human deaths by shark than any other
species. Jacques Cousteau considered it "the most dangerous of all
sharks" (Cousteau & Cousteau 1970).
Most of the
attacks on humans have occurred at shipwrecks or downed aircraft in
tropical seas far offshore, and particularly during World War II. The
most notorious tragedy involved the sinking of the USS Indianapolis
by a Japanese submarine on 30 July 1945, shortly after the ship
delivering the first atomic bomb to the U.S. air base at Tinian. Of
about 1200 crew aboard, 300 went down with the ship. The remaining 900
men faced exposure, dehydration, and shark attacks as they waited for
assistance. That assistance was delayed for days through numerous
bureaucratic bungles and some totally inexcusable negligence. The title
of Lech’s (1982) book says it all: All the Drowned Sailors:
Cover-Up of America's Greatest Wartime Disaster at Sea, Sinking of the
Indianapolis with the Loss of 880 Lives Because of the Incompetence of
Admirals, Officers, & Gentlemen. The Indianapolis
sinking apparently resulted in the most shark attacks on humans in
recorded history. Most of the attacks were attributed to the Oceanic
Whitetip. The attacks were the subject of actor Robert Shaw’s great
monologue, as Captain Quint in the 1975 film Jaws.
Screenwriter John Milius was brought in to write lines for this scene,
based on survivor stories. [Survivor stories are featured in more
recent accounts are by Kurzman (1992) and Stanton (2001).]
My lone encounter with this species was while working as a bird observer aboard the NOAA ship McArthur
on a four-month voyage of the eastern tropical Pacific in autumn 1989.
This was a tuna-porpoise survey cruise with a cadre of expert cetacean
observers. We encountered a large Oceanic Whitetip Shark, estimated by
me at 7-10' in length, near the decaying body of large baleen whale
(below), on 1 Aug 1989 at 21°17'N, 115°59'W [300 mi SW of Cabo
San Lazaro, Baja California]. A number of smaller sharks were in the
vicinity, and all were apparently scavenging on the carcass. I have no
photos showing any sharks here, but through PhotoShop® I've added a
bit of artwork of a Whitetip surfacing near the body [in reality, we
could see the sharks under the water but none surfaced.] The decaying
carcass had also attracted an estimated 300 Wedge-rumped Storm-Petrels,
and those shown in the photo are actual real birds.
The Shark-Watchers Guide
(Carwardine 2002) lists the Kona Coast of Hawaii, various reefs in the
Red Sea off the Sinai Peninsula, and Jervis Bay in New South Wales,
Australia, as predictable locations for divers to look for this
species. Local conditions change over time, so it is best to bet
updated information. Whitetips should not normally be a danger to
divers, but they can be nervous and unpredictable, and are a greater
danger in groups. A Whitetip may warn by 'gaping' (opening its mouth
without projecting its jaw) if divers get too close (Carwardine 2002). |
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dead baleen whale, prey for Oceanic Whitetip [shark artwork added to photo]: 1 Aug 1989 at 21°17'N, 115°59' W © Don Roberson (above)
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Caribbean Reef Shark Carcharhinus perezi in Nov 1980 at San Salvador I., Bahamas © Don Roberson (below) |
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Other sharks:
Although Quammen's list included just two sharks — and I follow that
pattern here — the ISAF has implicated at least 42 shark species in a
total of 980 attacks over the past 400 years. Many attacks go
unrecorded or unidentified as to species (especially those of wartime
ship sinkings). The ISAF estimates 70-100 shark attacks in a typical
year, with perhaps 5-15 fatalities. Of those that can be attributed to
species, three sharks are implicated in half of the attacks worldwide:
Great White (35%), Tiger Shark Galeocerdo cuvier (12%), and Bull Shark Carcharhinus leucas (8%). Other large or aggressive species implicated include Great Hammerhead Sphyrna mokarran, Scalloped Hammerhead S. lewini, and Shortfin Mako Isurus oxyrinchus. Even smaller species, such as Galapagos Shark Carcharhinus galapagenis or Caribbean Reef Shark C. perezi
(photo above) have been implicated in 'bump-and-bite' attacks. Yet, for
all of those statistics, hundreds of divers and snorkelers swim
peacefully with sharks every day. Many find that seeing a shark
underwater is a wonderful and exhilarating experience; see Carwardine
(2002 or updated versions) for information on when and where to go to
see sharks.*
Still, some of these are dangerous
sharks. Tiger, Bull, or Hammerhead sharks could easily be considered
among the 'monsters of god.' You don't have to gripe about my inclusion
of Anaconda or Mugger Crocodile if you don't like those choices. Feel
free to pick any big shark instead!
I should add
that the name of this page — "Two Fish and a Lizard" — is technically
inaccurate. Ellis (1975) argues that sharks should not be considered
"fish" in the evolutionary sense, since "fish" are not a monophyletic
group. "Sharks," Ellis says, "are not bony fishes that took a wrong
turn on the evolutionary road; they are a unique and distinct line that
shows as noble a history as their teleost [bony fish] cousins." The
genetic evidence apparently shows that cartilaginous "fishes," class
Chondrichthyes, consisting of sharks, rays and chimaeras, appeared by
about 395 million years ago. The bony "fishes," class Osteichthyes,
have a bony skeleton rather than cartilage, and they first appeared in
the fossil record about 416 million years ago. As different classes,
sharks and bony fishes are as different from each other as birds are
from snakes, so, in truth, sharks are not "fish" as we tend to
visualize them. Still, in speaking of monsters, "two fish and lizard"
has a nice ring to it, even if technically off-key.
[Some
fish can be dangerous in packs, such as piranhas in South America —
some 30-60 species of omnivorous small fish in 3 genera. Fatal attacks
most often involve the Red-bellied Piranha Pygocentrus nattereri of the Amazon Basin. Teddy Roosevelt wrote in his 1914 book Through the Brazilian Wilderness:
"They are the most ferocious fish in the world. Even the most
formidable fish, the sharks or the barracudas, usually attack things
smaller than themselves. But the piranhas habitually attack things much
larger than themselves. They will snap a finger off a hand incautiously
trailed in the water; they mutilate swimmers—in every river town in
Paraguay there are men who have been thus mutilated; they will rend and
devour alive any wounded man or beast; for blood in the water excites
them to madness." Likewise, the Goliath Tigerfish Hydrocynus goliath,
found in the Congo River system and Lake Tanganyika, and some smaller
relatives, are aggressive predators than hunt in packs and have
attacked people. Yet none of these fish qualify as a "monster of god"
because a single fish is neither an alpha predator nor a dangerous to
life. Like wolves and hyenas, it is the pack that can terrify.] |
*
I do have some personal experience with some of these sharks. In the
Pacific, I observed a 8' Hammerhead, possibly Great, next to our ship
on 30 Oct 1989 at 1° N, 87°50' W [about 200 NE of the
Galapagos], and another 15 Nov 1989 at 5°20'S, 94°10'W [500 mi
W of northwest Peru]; and in the Atlantic a 5' Hammerhead, probably
Scalloped, on 3 Sep 1982 some 20 mi offshore of Port Canaveral, Florida. |
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Komodo Dragon on 21 Oct 1999 Rinca I., Indonesia © John Sullivan (below) |
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Komodo Dragon Varanus komodoensis
is the world's largest lizard. It is a species of monitor endemic to a
very few islands in the Lesser Sundas, Indonesia — primarily Komodo and
nearby Rinca, both of which lie off the western tip of Flores. They
swim well, so other islets may host them as well. Once thought to be an
example of island gigantism, recent studies suggest that giant monitors
were once a ubiquitous part of the subcontinental Eurasian and
Australasian faunas more than 3.8 million years ago. Extinction played
a pivotal role in the reduction of their ranges and diversity, leaving
only only the Komodo taxa, termed Komodo Monitor by some, as an
isolated long-term survivor (Burness et al. 2001, Hocknull et al.
2009).
Komodo Dragon is largely a solitary,
opportunistic, sit-and-wait ambush predator at the top of its food
chain. Its maximum size is about 3m (10 ft) and it can weigh up to 70
kg (150 lbs). Large adults take large mammals, such as deer, but also
consume a fair bit of carrion. Although they generally avoid humans, a
few unprovoked attacks of predatory nature are documented (Auffenberg
1981). Attacks go for the throat, and when the prey is dead, large
chunks of flesh are torn from the carcass and swallowed whole. There is
very much a hierarchy in the wild, with larger dragons dominating.
After wrestling battles between lizards of similar size, the loser
generally retreats, although it has been known for the loser to be
killed and eaten by the victor (Auffenberg 1981). It has been claimed
that Komodo Dragons have a venomous bite, and three are poison glands
in the lower jaw, but their biological significance is debated. There
are also contesting views about whether their saliva has septic
pathogens; see Ciofi (2004), Fry et al. (2009), and Goldstein et al.
(2013).
I have not yet seen a Komodo
Dragon; I need to plan a trip to the Lesser Sundas. David Quammen
visited Komodo during his research for his classic book The Song of the Dodo (1996). With a local guide, he sought to see the Dragon on his own terms, in the wild. Here is his account:
Later
in the day David Hau and I hike out into the habitat. We follow a set
of komodo tracks along a dry streambed through the forest. The
streambed leads up toward the head of the valley. We come to a wall of
lava, the vertical face of a volcanic bluff rising out over the
treetops. David shows me several small caves where komodos have denned.
. . . We circle around the bluff and emerge from the forest into sunlit
savanna. . . Here we find bits of femur or humerus, half-crushed by
mastication. "Deer. Komodo is here one time," David says, lifting a
bone fragment. "He can eat all."
From this
quiet moment, events lurch forward rapidly. As I inspect the bones,
David glasses the opposite slope of the valley with my binoculars. "Ah,
komodo!" he chirps. "Komodo!" With his guidance, yes, I can barely spot
it: a dark elongated form, half a mile away, on a light patch of dirt.
It doesn't budge. It's basking. Or else I've trained the binoculars on
a komodo-shaped log. All right, I console myself, that's better than
nothing. . . We climb off the rock and ascent toward another large
bluff.
We notice a commotion just ahead in the
brush. Then a very large komodo breaks into view, spooked by our
trespass, and scrambles straight up the vertical face of the bluff,
like an alligator scaling a four-story building. Lumps of rock crumble
and fall. My jaw drops like the lid of a dumpster. . . . How big is it?
I couldn't say . . . (maybe) nine feet and two hundred pounds — but for
God's sake the beast is galloping up a cliff !
I
raise my binoculars in time to see the komodo take the summit. It
pauses there, a giant reptilian silhouette against the bright sky. Then
it tops over, disappearing beyond views. At that moment I hear David
scream as another big komodo charges out of its hiding place just
behind us. Yaaaggh. We whirl, caught flat.
But
this animal makes a split-second decision against cutting us off at the
knees. Maybe it isn't hungry. Maybe we smell unappetizing . . . but for
some reason it has chosen not to attack. Instead of snatching a
mouthful of my buttocks or biting away David's left calf, it had peeled
a sharp turn and set off downhill, moving as discreetly as a
rhinoceros. We give chase at precisely the right pace to assure that we
won't catch up. . . When our giddiness has subsided and our breathing
is normal again, we begin working our way off the grassy hillside. . .
Twenty stops on, we find the severed head and neck of a rusa deer, a
three-point stag attended by a million hysterical flies . . . It looks
like it was hit by a train.
I recall what David has just said about the komodo: "He can eat all."
Elephants, goat hooves, buffalo bones, humans, and certainly a morsel
like this. Chances are good, then, that the komodo will be back. And if
not the same one that made the original kill, then others that catch
the scent. Leaving the fly-blown head to its various claimants, we
clear out. |
If
David Quammen himself can be attacked by a Komodo Dragon, what chance
to the rest of us have? Apparently the Indonesian park service
understands this now, and one is not allowed to venture away from the
packs of tourists in their planned regimen. John Sullivan describes his
1999 experience on his website [Wild Herps]
this way: "The highlight of our trip to Indonesia and the islands in
Komodo National Park was, of course, the legendary Komodo Dragon,
largest lizard in the world. And possibly the only lizard around that
occasionally eats people. We saw this mangrove-wanderer soon after we
got off the boat onto Rinca, the island neighboring Komodo." They saw
two " huge adults, maybe 8 feet long. The largest one ever reliably
measured was slightly over 10 feet long. The really big ones that we
saw spent most of their time lying about. Occasionally one would
sloooowly rise to its feet, instantly escalating the tension level of
any human observers. The third one [seen was] a young adult; big enough
to live on the ground. (Until the age of two or so they live primarily
in the trees, thus avoiding being eaten by the larger ones.) The
younger ones we saw were considerably more active than the huge ones;
they were generally wandering about tasting the scent of the air
constantly with their long forked tongues."
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Komodo Dragon on 21 Oct 1999 Rinca I., Indonesia © John Sullivan (above) |
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Click below for the next page of this project
OR use these LINKS to the SPECIES PAGES
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Photos: All photos © Don Roberson, except as otherwise attributed; all rights reserved.
Literature cited:
Burness,
G., J. Diamond, and T. Flannery. 2001. Dinosaurs, dragons, and dwarfs:
the evolution of maximal body size. Proc. Nat. Acad. Sci. USA 98:
14518–23.
Carwardine, M., and K. Watterson. 2002. The Shark Watcher's Handbook. Princeton Univ. Press, Princeton, N.J.
Ciofi, C. 2004. Varanoid Lizards of the World. Indiana Univ. Press, Bloomington, IN.
Compagno,
L.J.V. 1984. FAO Species Catalogue. Vol. 4. Sharks of the World. Part 2
- Carcharhiniformes. FAO Fisheries Synopsis 125: 251–655.
Ellis,
R. 1963, 1975. The Book of Sharks: a Complete Illustrated Natural
History of the Sharks of the World. Harcourt, Brace, New York.
Fry,
G.G., S. Wroe, W. Teeuwisse, M.J.P. van Osch, K. Moreno, J. Ingle, A.C.
McHenry, T. Ferrara, P. Clausen, H. Scheib, K.L. Winter, L. Greisman,
K. Roelants, L. van der Weerd, C.J. Clemente, E. Giannakis, W.C.
Hodgson, S. Luz, A.P. Martelli, K. Krishnasamy, E. Kochva, H.F. Kwok ,
D. Scanlon, J. Karas, D.M. Citron, E.J.C. Goldstein, J.E. Mcnaughtan,
and J.A. Norman. 2009. A central role for venom in predation by Varanus komodoensis (Komodo Dragon) and the extinct giant Varanus (Megalania) priscus. Proc. At. Acad. Sci. USA 106: 8969–8974.
Goldstein,
E.J.C., K.L. Tyrrell, D.M. Citron, C.R. Cox, I.M. Recchio, B. Okimoto,
J. Bryja, and B.G. Fry. 20120. Anaerobic and aerobic bacteriology of
the saliva and gingiva from 16 captive Komodo dragons (Varanus
komodoensis): new implications for the "bacteria as venom" model. J.
Zoo & Wildlife Medicine 44: 262–272.
Hocknull,
S.A., Piper, P.J., van den Bergh, G.D. Morwood, M.J., and I. Kurniawan.
2009. Dragon's paradise lost: paleobiogeography, evolution and
extinction of the largest-ever terrestrial lizards (Varanidae). Free
access PLoS One.org/article/info:doi/10.1371/journal.pone.0007241
Lech,
R.B. 1982. All the Drowned Sailors: Cover-Up of America's Greatest
Wartime Disaster at Sea, Sinking of the Indianapolis with the Loss of
880 Lives Because of the Incompetence of Admirals, Officers, &
Gentlemen. Stein & Day, New York.
Kurzman, Dan. 1992. Fatal Voyage: The Sinking of the USS Indianapolis. Pocket Books, New York.
Quammen, D. 1996. The Song of the Dodo. Scribner, New York.
Quammen, D. 2003. Monster of God: the Man-Eating Predator in the Jungles of History and the Mind. Scribner, New York.
Stanton,
Doug. 2001. In Harm's Way: The Sinking of the USS Indianapolis and the
Extraordinary Story of Its Survivors. Harry Holt, New York.
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