Prehistoric Extinct Sharks
SHARK CHAT FORUM
News of Sharks
23 , 2013
- 3,500 lbs Great White
Shark getting a Little too close.
The most exciting piece of fishy news this week has almost
nothing to do with local angling and everything due to
sensationalism. Sadly, it should be rated up their with the
National Geographic Channel or Animal World as it involves
cutting edge research but, for most people, the word “shark”
and especially “great white shark” evokes completely
After having travelled thousands of miles up and down the
American East Coast in a relatively short five months, a
report that the almost 3,500 pound behemoth has been tracked
electronically to within a few miles (in the ocean, even a
100 miles isn’t a lot) of Bermuda has put a lot of local
potential skinny dippers off taking the plunge. It isn’t
just the chilly water temperature but the fear of being a
shark’s supper that is keeping people out of the water.
It is funny how a bit of information can cause a stir. Has
it occurred to anyone that Mary Lee may well be on her way
here to join 1,000 of her friends and family or to take part
in some sort of feeding frenzy? The latter is unlikely to
include Homo sapiens, given the incidence of shark attacks
of any sort around here. Just inject the thought of a bit of
night swimming and there you have it, mad panic — many
thanks, Peter Benchley!
Do those same people ever think that great whites have
occurred here before and been properly documented by those
who know about such things? Not to mention the many other
shark species that normally occur here that have earned the
moniker “man-eater” elsewhere in the world. Include the
familiar tiger shark and the less commonly seen but
nonetheless present oceanic white-tip shark as species that
have earned that title.
What this area does lack are the huge schools of oily
baitfish that are the preferred dining venues for giant
tunas and the sharks that often travel in their wake,
picking up the pieces. Something that some may not have
noticed is that the spring wahoo run (anytime form late
April until early June) often brings with it some mako shark
activity. There are plenty of stories of half wahoo being
reeled in or specimens that have pretty well been shredded
during the process of their capture.
There is no reason why makos don’t effect similar movements
for similar reasons that great whites make their migrations.
Having said that, water temperature may have something to do
with things as well. Makos are thought to be more tropical
than great whites but who isn’t to say that Mary Lee may
have gotten into an eddy of water at a favourable
temperature and just be staying within its confines even
though it is moving toward Bermuda.
To look at some of the more positive outcomes of this story:
this is one of the few instances where a specimen of a
large, relatively rare species has been tracked reliably
over enough time. Although the data is excellent, it really
goes to show just how much more is needed before any
definite conclusions can be drawn. The same goes for marlin
and tuna research. A huge amount of data is needed to even
start to fathom out the mysterious world of oceanic apex
The other item which is of obvious angling interest was the
local capture of a swordfish that dressed out at around 110
pounds. The catch was made by a well-known commercial
fisherman who has always been willing to experiment with new
and different tactics. One of these is the night-time
trolling for swordfish that has become popular in Florida
For some time now, drift fishing at night has been the means
by which swordfish were caught by sportsmen.
It has been attempted here with some success but never
really caught on. Local anglers are pretty set in their ways
and it is the daylight fishing for wahoo, tuna and marlin
that is the norm and certainly is the basis for tournament
The new trolling technique, probably developed by an
insomniac, is advantageous in that it allows fishing to be
conducted while travelling to and from the fishing grounds
(remember that off the US it is often a long run to the deep
blue water and some boats do leave at night in order to be
offshore at daybreak) and because the trolling speed is
slow, it is easier on the fuel bill.
It is not as if it wasn’t known that swordfish inhabit local
waters. In fact, there aren’t too many places where there is
not a fishery for swordfish and in some places these
fisheries are, literally, ancient.
Swordfishing in the Mediterranean goes back an awfully long
way having been mentioned in early literature before the
time of Christ. There is little doubt that fishing for
swords was going on long before anyone decided to write
anything about them, so “ancient” is probably an apt
description of the Mediterranean fishery for this species.
So long has the Mediterranean fishery gone on, that there
are some who accept that the species in that sea is, in
fact, separate to that found everywhere else. The fish are
smaller versions of the oceanic swordfish and there is
evidence that they mature earlier.
This would be consistent with the pressure put on the
species by thousands of years of exploitation by man in a
relatively small body of water. Entire fleets of boats have
been developed for the swordfish harpoon fishery which
continues to be one of the main ways in which swords are
In any case, there is a worldwide fishery for swordfish
which are found in all the major oceans. Ever-increasing
demand has led to some international controls on effort and
landings; but, as is usually the case, the net effect of
such regulation leaves a lot to be desired. Given that the
total Bermuda catch pales into insignificance on the world
stage and the remote likelihood that any form of angling for
this species is going to catch on to any great length,
landings of swordfish are likely to remain at the incidental
With the first real signs of spring just starting to emerge,
it will be some time yet before sport fishing again comes
into its own. There are a few unconventional aspects of
fishing that one might be able to indulge in and, naturally,
there was the usual wise guy who suggested that an effort
should be made to catch Mary Lee. Any such action would
undoubtedly be frowned upon by a good many even though it
would more than certainly provide some exciting and
immensely Tight lines!
22 , 2013
- Indonesia has announced
a new shark and manta ray sanctuary, the first to protect
the species in the rich marine ecosystem of the Coral
Triangle, known as the "Amazon of the ocean".
Environmentalists Wednesday welcomed the creation of the
46,000-square-kilometre (18,000-square-mile) protection
zone, in an area at risk from both overfishing and climate
The local government in Raja Ampat on the western tip of New
Guinea island announced the move this week, issuing local
regulations to ban the finning and fishing of sharks in the
area, a tourist destination popular with divers.
Rizal Algamar, Indonesia director of the Nature Conservancy,
described the regulations in a joint statement with
Conservation International as a "breakthrough in policy".
"Scientific evidence states that the value of live sharks
and manta rays far outweighs the one-time profit of dead
sharks and manta rays, benefiting a growing world-class and
increasingly popular marine tourism and dive destination,"
Scientists have warned the Coral Triangle, which spreads
across a vast area of Southeast Asia's waters, is under
threat, with heat-trapping carbon gases blamed for creating
acidic seas hostile to much marine life.
Overfishing has also been a problem, but the sanctuary will
support existing no-take zones that have helped shark
numbers slowly recover.
"Sharks in particular play an important role, as apex
predators at the top of the food chain, maintaining
fisheries and ecosystem health," the statement said.
The sanctuary is also expected to prevent a drop in manta
ray numbers, with the species' gills increasingly used in
Shark populations are in a rapid and steep decline
worldwide, facing intense pressure from fishing and in high
demand for shark fin soup.
Up to 73 million sharks are killed annually, mostly for
their fins, the statement said. As a result, many shark
species have suffered declines greater than 75 percent and
in some species up to 90 percent or more.
Indonesia ranks as the world's largest exporter of sharks
21 , 2013
- A glow-in-the-dark shark
scares off predators with "lightsaber-like" spines on its
back, a study suggests.
The research was carried out on the velvet belly
lanternshark, a small species found in the deep waters of
the Atlantic Ocean and Mediterranean Sea.
The scientists believe that while the light-up spines can be
seen by larger, potentially dangerous fish, they are harder
for the shark's prey to spot.
The study is published in the Nature journal Scientific
This species of lanternshark (Etmopterus spinax) lives in
the mesopelagic zone of the ocean, which has a range between
200m and 1,000m in depth.
It is a diminutive shark; the largest can measure up to
about 60cm in length, but most are about 45cm long.
Until recently, little had been known about this species,
apart from the fact that like many deep sea creatures it has
the ability to glow - a trait called bioluminescence.
Previous research found that the shark has light-producing
cells called photophores in its belly, and it uses this
light to camouflage itself.
"Imagine you are below the shark, the shark is swimming and
you have the light from the Sun coming down," explained Dr
Julien Claes, a shark biologist from the Catholic University
of Louvain in Belgium, and the lead author of the study.
"If you are just below the shark what you are going to see
is a shadow. So imagine if the shark can actually produce a
light, which is identical to the light produced by the Sun.
Then the shadow of the shark is going to disappear."
Any prey lurking below, typically a small fish called
Mueller's pearlside, will not see the shark coming.
However, this new study revealed that the shark is also
luminescent on its top side.
Dr Claes said: "There are two spines, one in front of each
dorsal fin, and just behind them you have two rows of
photophores. They are like lightsabers - they illuminate the
"It was surprising - why would you try to be invisible from
below but visible from the dorsal side?"
Visual modelling experiments revealed that potential
predators could see the light from several metres away.
The shark's prey, however, could only see the glow from a
distance of about 1.5m, giving them less chance of making an
The team concluded that the glowing spines were acting as a
beacon, illuminating the shark's threatening spines.
Dr Claes: "It's a way to say: 'Don't bite me, I'm dangerous,
I have spines on my back. You could be hurt.'
"When you live in this dark place, what you try to do is
avoid is to be seen by other animals, because there are no
places to hide.
"It can be very dangerous - you put yourself at risk when
you produce light from your back, unless it acts as a
He said it was unusual to find an animal that was using
light to both hide and advertise itself at the same time.
"It's surprising that these two apparently opposite
behaviours can occur in a single organism at the same time.
It is really paradoxical."
SHARK NEWS ARCHIVES
( As of December 2012 )