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Threatened predators
The
word "shark" refers to any of the cartilaginous fishes
of the order Selachii and the class Chondrichthyes (sometimes also
called Selachii). Sharks are carnivorous and make use of food items
ranging from plankton and fishes to seals and garbage. The young
in most species hatch within the female and are born alive. There
are estimated 350 living species of sharks. Ranging in size from
the dwarf shark and pygmy ribbontail catfish shark (less than 30
cm) to the whale shark (up to 21 meters), they are magnificent creatures,
able to live in every marine environment from the Arctic to the
tropics and playing a crucial role in keeping aquatic wildlife in
balance. Most sharks function as apex predators. They keep prey
populations in check. They also eat the slowest and weakest individuals,
leaving the smarter, stronger ones to reproduce and thus improving
the target species’ gene pool.
Geologic
age: 400 million years
Issues and
threats: Each year, between 30 million and 100 million sharks
are caught for their meat, fins, hides, jaw, and internal body parts.
At least one is accidentally killed, usually by longlines set by
shrimp and tuna boats, for every one that is caught deliberately.
As a result, populations of some shark species have fallen about
80% over the past 10 years. At this rate, experts estimate some
species could reach ecological extinction within 10 years.
Scientific
name: Rhincodon typus
Common
names: Whale shark, butanding, balilan, tawiki, isdang tuko,
tuki-tuki
Weight:
up to 25 tons Length: 12-21 meters
Distinguishing
marks or features: Dark gray, blue gray, purplish to reddish
brown bodies, reddish or greenish gray above, with large white or
yellow spots and transverse stripes; small conical teeth; huge,
almost terminal mouths for filter feeding. Whale sharks are oviparous
(egg layers). Though ferocious-looking, whale sharks are gentle
creatures that feed primarily on microscopic marine organisms called
plankton.
Food:
Plankton, squids, crustaceans and small fishes like anchovies and
sardines.
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Whale sharks are considered as delicacies and served in banquets.
But while the hunt used to be limited to local consumption, it is
now done chiefly in response to increasing export demand. At least
two companies are involved in the export of whale sharks, mainly
to Taiwan, Hong Kong, Singapore and Japan. Each shark, cut and frozen,
fetch as much as P800,000. These companies reportedly buy whale
sharks from fishers for as high as P80,000 apiece, sometimes even
offering boats and other means of support to the fishers.
Protection efforts: Fisheries Administrative Order No. 193,
Series of 1998, prohibits the catching, selling, buying, possessing,
transporting and exporting of whale sharks and manta rays in Philippine
waters as well as the wounding and killing of these animals when
targeting other fish. In addition there are local ordinances that
ban the killing of whale sharks in certain municipal waters.
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