 Hi Guys & Gals,
If you can print this and keep it in your truck just in case you hook a shark and don't know what kind it is, these pictures will tell it all.
it'll be an education for all of us , we're never to old to learn .
I have been hearing about sharks being caught , some say brown, some don't know what kind they were , Hope this information may help some of you anglers out Good Luck SHARKS
Sharks are a fascinating group of fishes that strike fear into the minds of
humans. This fear is really a fear of the unknown, for little evidence exists
that indicates sharks are really very dangerous. Sharks have much more to fear
from humans than humans have to fear from sharks. Each year thousands of tons of
sharks are killed by fishermen for food and other products while very few humans
are ever bitten, and fewer still die from shark bites.
Sharks belong to the class Chondrichthyes, a group which also includes rays,
skates and chimeras. Unlike other vertebrates, sharks have a skeleton made of
cartilage rather than bone. Only about 800 species of cartilaginous fish are
known to exist compared to over 20,000 known species of bony fishes.
Sharks differ from the more common bony fishes in several ways. Besides
having no bones, sharks and their relatives do not have the overlapping scales
that cover many bony fish. Nor do they have a swim bladder, the air-filled
balloon-like organ that keeps most fish upright. Sharks have gill slits but no
gill-cover, which is common to the bony fish.
Sharks vary greatly in size from the enormous 40-foot-long whale shark to
tiny two-to three foot dogfish and angel sharks. Despite its huge size, the
whale shark is not an active predator. It feeds rather passively by swimming
with its mouth open to collect plankton and small fish.
Most sharks are active predators and eat primarily fish, although the great
white shark will also prey upon seals, sea lions and other marine mammals. Some
sharks eat bottom-dwelling animals such as crabs, and others scavenge for dead
animals. Some sharks even eat trash as indicated by the tin cans and boots found
in sharks' stomachs.
Because they have no swim bladder to keep them buoyant, sharks sink when not
swimming. Sharks' bodies are heavier than water. The nurse shark, skates and
rays have adapted to resting on the bottom, but most sharks are constantly on
the move. Moving forward with their mouths open is how sharks move water across
their gills for breathing. Most cannot stop for long or move backwards as can
bony fishes.
Shark teeth come in a variety of sizes and shapes. Some are narrow and
pointed and others are broad and sharp; still others are serrated and jagged
depending on their food preference. Sharks can have several rows of teeth in
their mouth. When one tooth breaks off another moves forward to replace it.
Fossil teeth are often found in great numbers by beachcombers searching the
southeast coast of the United States. Great collections of teeth are also found
along Gulf of Mexico beaches.
Examples of Shark Teeth
Sharks are well adapted to their watery environment. They have good eyesight
and the ability to see colors. Their eyelid closes from the bottom of the eye.
Even when the water is not clear, or when it is dark, sharks can easily locate
their prey. They have an excellent sense of smell and can smell the odor of
their prey from over one-quarter of a mile away.
Even better than its sense of smell is a shark's ability to detect the
vibrations of other animals in the surrounding water. These vibrations are
picked up by the lateral line, a row of sensitive fluid-filled sacks extending
from the head to the tail of a fish. Even in the dark, a shark can sense the
movement of prey or enemies through its lateral line.
Through pores in their skin, sharks also can detect the weak electrical
charges produced by other animals. This sense allows them to find prey in the
dark or buried in the sand .
Most sharks do not lay eggs for external fertilization as do most fish.
Sharks practice internal fertilization more resembling the habits of mammals.
Many sharks also bear their young alive, fully developed, and few in number.
Because sharks produce so few young with each mating, fishermen and other
predators can quickly reduce a population of sharks.
Some sharks do lay fertilized eggs, which are sometimes found on the beach.
These eggs are commonly called "mermaids' purses." In southern waters
of the United States most "mermaids' purses" come from skates.
Most sharks are high on the ocean's food chain. They typically eat thousands
of smaller fish during the course of their lives. As predators, they conserve
energy by eating the slow, weak or sick fish in a school. They are, therefore,
important to the ecological balance of the marine environment in that they
eliminate the genetically weaker animals in a population.
The role of sharks in the marine environment is similar to the role of the
great cats (lions, tigers and cougars) in terrestrial environments. Cats
eliminate the weak or slow animals in a herd of wildebeests or deer in the same
way as sharks eat the slower fish in a school of mackerel or herring.
Sharks provide many products that are utilized by humans. The flesh of sharks
is excellent food, although Americans have not traditionally considered shark
meat as a favorite food. An enormous shark fishery does exist in the United
States for export to other countries. Sharks are often caught only for their
fins which are used in shark-fin soup, an Asian delicacy. The livers of sharks
are rich in oil, which is used for its vitamin A content and as a lubricant. The
skin of sharks is used as leather and as fine sandpaper, called shagreen.
In general, sharks are much maligned. They are considered dangerous, wanton
killers by many people. Their job is to live by eating, breathing and
reproducing like other animals on this planet. Sharks evolved millions of years
before humans. They eat fish and other marine animals, which exist in their
environment. People are not part of a shark's normal diet. Most "shark
attacks" are accidental, a case of mistaken identity. Perhaps a dozen of
the 300+ species of sharks have been implicated in killing humans.
Twenty families of sharks have been described in the waters off North
America. The following section briefly describes the five species found around
Gray's Reef National Marine Sanctuary.
The Nurse Shark
The nurse shark is a relatively slow, sluggish shark often seen resting on
the bottom. These sharks feed on benthic (bottom-dwelling) animals such as crabs
and shrimp. They can be recognized by the barbels (fleshy appendages) that hang
below their nose. Barbels are sensory organs, which help the nurse shark locate
food on the bottom.
Nurse sharks reach an average length of 6' to 10' and an average weight of
300 pounds. They are considered dangerous to humans only if aggravated.
The Spiny Dogfish
The spiny dogfish is the most abundant and best known of the sharks found on
the east coast of the United States. This small shark is frequently found
traveling in large schools. Recognized by its two dorsal fins, each with spines,
the spiny dogfish is a favorite shark for laboratory dissections. Its flesh is
eaten by people and often used for cat and dog food. These sharks eat many kinds
of small fish and also invertebrates such as squid and octopus.
The spiny dogfish only grows to around 3' to 4' in length. Males take eleven
years to mature and females between eighteen and twenty-one years to mature. The
gestation period of the spiny dogfish is the longest of any vertebrate animal.
It takes from 20 to 24 months from fertilization until young spiny dogfish are
born.
The Lemon Shark
The Lemon shark belongs to one of the largest families of sharks, the requiem
sharks. This family includes many of the better known sharks including the tiger
shark, the blacktip shark, the bull shark, sandbar shark and blue shark. It is
interesting that a requiem is a hymn or mass for the dead. Several of these
sharks are reported to be responsible for "shark attacks."
The yellowish color on its sides gives the lemon shark its name. It is a
common shark along the southeast coast of the United States. It eats mainly bony
fish but will also eat shrimp, crabs and other small sharks.
Lemon sharks grow 6' to 8' in length with a weight exceeding 200 pounds.
The Tiger Shark
The tiger shark is one of the largest sharks in the ocean. The tiger gets its
name from the vertical black stripes that commonly appear on its sides. Tiger
sharks will eat almost anything including conchs, skates, fish, sea turtles,
birds, horseshoe crabs, and even human garbage.
This shark also is a requiem shark and may be responsible for human
casualties. Tiger sharks are caught as a gamefish and can weigh as much as 2,000
pounds.
The Great Hammerhead
Hammerheads are named for and easily recognized by the unusual shape of their
heads. Their wide heads are thought to serve the same purpose as the bow rudders
used in maneuvering undersea submersibles and submarines. Hammerheads are quite
common in warm ocean waters. They are active predators that feed primarily on
fish and squid.
The great hammerhead can reach a length of up to 18', with a weight of 1500
pounds. They are considered to be one of the few sharks that can be dangerous to
humans.
very interesting to read.
Guppie
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