You are not the only one imagining a
swimming yellow lemon with teeth and fins after hearing the name lemon shark.
Actually, there is not much lemon like quality in that shark except a slight
lemon tint on its skin. The color was the reason behind that unusual name.
Scientists are no nonsense folk who call it
Negaprion brevirostris. In fact, there are two types of lemon sharks – N.
brevirosris and N. acutidens (sickle fin or sharp tooth lemon shark). There was
another species (now extinct) N. eurybathrodon.
Lemon sharks are requiem sharks (Carcharhinidae)
like the great white or hammerhead. That family of sharks belongs to the order Carcharhiniformes
or ground sharks.
Size
Lemon sharks are generally regarded among
the big and powerful sharks. The largest specimen ever was 3.43 m (11.3 ft) and
183.7 kg (405 lb). But most common size is 9 to 10 ft (2.7 to 3 m).The weight
of the full grown shark is about 90 kg (200lb). Like other requiems, the female
is bigger than the male.
Video: Lemon Sharks Feeding Frenzy
Anatomy
The head of a lemon shark is flattened.
There is a short and broad snout. The skin color is slightly yellow. The color
helps to camouflage on the sands under the ocean.
1st and 2nd dorsal
fins are almost same in size. There are other common fins like big pectoral
fins and the caudal fin, smaller pelvic and anal fins.
There is a special organ inside their head
to detect prey. That organ is called ampullae of Lorenzini. It can detect the
electric field of any living animal from far.
Habitat and Distribution
Lemon sharks live in the shallow warm ocean
waters of the tropical and sub-tropical regions. Their main concentration is in
the western Atlantic from United States to Uruguay. The east coast has only
limited numbers along the coast of Senegal and Cote de Ivory. Some lemons also
live in the western Pacific, from Bay of California to Ecuador.
River mouths, mangroves, coral reefs and
bays are the favorite habitat of the lemon shark. They does not like the open
ocean and so stay within the limits of the continental slopes. The shark
generally roams within the depth of 90 m (300 ft). But they can go to the open
ocean only during the migration.
Breeding
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| Baby lemon shark |
Lemon sharks are viviparous. The egg is
hatched inside the body. The mother has to carry the baby inside their body until
they become more mature. After a gestation period of 9 to 10 months the mom
gives live birth of 10 to 30 cubs.
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| Pregnant lemon shark |
Mangroves are their favorite nursery sites.
In the site the babies are born. They live their until they become strong
enough to survive in the ocean. The sharks return to the place every year
during the season of giving birth.
Feeding
Lemon sharks become active in the night in
search of food. The main food item is different types of bony fishes. The shark
is slow and show they prefer slower fishes. Some fishes prefer to hide
themselves rather than fleeing at full speed. Lemon sharks love to find these
fishes and eat them.
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| Lemon shark attacking a school of fish |
They also eat different types of
crustaceans like crabs, shrimps and lobsters. They also eat other sea bed
invertebrates like tunicates. The stingrays are also often become victim of
these sharks hunger. Juveniles often eat each other for survival.
Social Behavior
Generally sharks are single animals. But
lemon sharks often make big groups. There are also hierarchy in the group with
leaders and followers. They can also haunt in groups with perfect coordination
– which is very uncommon among sharks. When one victim is attacked by an
individual, the feeding frenzy begins where many joined the party.
In fact, lemon sharks are probably smartest
among all sharks. Their body to brain ratio is also higher than other sharks. The
shark can learn from experience and interact with others in a group.
Interaction With and Attack on Humans
Lemon shark is edible. In some regions the
meat is very popular. So, thousands are killed for meat. The skin of the fish
is also valuable. The fin is also used in the soups in East Asian countries.
The result is overfishing of the species and steady decline of its numbers. The
shark is now in the IUCN threatened list.
Lemon sharks are slow to move and non
aggressive in nature. So, it is no danger to humans. Incidents of lemon shark
attack on humans are rare. But it is not advisable to disturb it. Some people were
bitten in the past for such mistakes. Remember it is a big shark with too
powerful jaws which can result in some serious damage.
Some Interesting Facts
- The teeth of a lemon shark are curved. The curving helps them to catch slippery prey like fishes.
- Despite of having bog eyes, a lemon shark has poor vision. Moreover, they haunts at night when the ocean is dark.
- The poor eyesight is compensated by a very strong nose. The shark can smell blood in the water from a few miles away.
- The shark can live very well in aquariums. So, many aquariums have them. That has helped the experts to learn many things about sharks.
- Parrotfish is a colorful tropical fish. It is one of the most favorite foods of lemon fish. It tries to camouflage to hide itself from the shark but almost every time fails.
- Lemon sharks are selective feeders. They attack the medium sized fish among a group of fishes of different size.
- Most other sharks roll to rip off flesh from large prey’s body after a solid bite. The lemon shark is an exception; they shake their head from side to side to do it.
- The shark lives in a group of similar size. So, bigger sharks make one group while smaller ones make another.
- The females of the species mate with multiple males within a short period of time. Unlike other animals they do it even after pregnancy. The practice is done for not being disturbed and chased by the males.
- Sometimes lemons sharks can go to brackish or fresh waters. They can survive for a few hours in the rivers but never go far upriver.
Conclusion
We have learned many fascinating facts
about lemon sharks today. If you have read so far then you were interested to
know about the shark. It is possible that you know something that I don’t know.
If it is the case then why don’t you share your knowledge with me and other
readers of this website?
If you want to read more about sharks then there are some listed below for your convenience:-
Porbeagle shark
Nurse shark
Tiger shark
Port Jackson shark
Brown banded bamboo shark
Dogfish
