Nurse sharks are classified under the category of carpet sharks (they belong to the order Orectolobiformes, family Ginglymostomatidae) with the scientific name Ginglymostoma cirratum. They have played a very important role in shark research programs in recent years.
This species of shark has a total length of about 7.5-9.7 ft (2.2-3 m) starting from the tip of the mouth to the tail.
They are amazing docile species and are also known by a famous nickname: 'couch potatoes of the sea' due to their lazy nature. In general, they are nocturnal carnivorous fishes who swim from the deeper waters to the shallow area to attack their prey.
They are quite gentle compared to the other species of sharks and are social among themselves.
The closest relatives that a nurse shark has are whale sharks, zebra sharks, bamboo sharks, and the wobbegongs. This article contains interesting common nurse shark facts as well as grey nurse shark facts that talk about the environmental biology of fishes.
For similar content check out the articles on bull sharks and goblin sharks.
Nurse Shark Interesting Facts
What type of animal is a nurse shark?
The nurse shark (Ginglymostoma cirratum) is a cartilaginous fish so it belongs to the category of elasmobranch fish.
What class of animal does a nurse shark belong to?
Nurse sharks belong to the class Chondrichthyes.
How many nurse sharks are there in the world?
There is no proper count for the entire population of nurse sharks in the world. The conservation of the gray nurse shark is taking place in in the Eastern Australian coastal waters.
They have been provided protection there for the last 20 years, but their population is still declining continuously. At present, Eastern Australia is home to 1,000-1,500 gray nurse sharks approximately.
Where does a nurse shark live?
Nurse sharks have a wide distribution all over the world. From the extreme east to the west, their presence is everywhere.
Nurse sharks prefer coastal waters of tropical and subtropical areas. They are found in the Western Atlantic Ocean, the eastern Pacific Ocean, and the Eastern Atlantic Ocean.
They live exclusively in warmer waters and closer to the coastal lands. In the western Atlantic Ocean, their distribution ranges from Rhode Island to southern Brazil as well as the Caribbean. In the Eastern Atlantic, they are distributed from Cape Verde to Gabon.
Around the Eastern Pacific Ocean coast, nurse sharks are found in the northern parts of the United States to the coast of South America. The species of gray nurse sharks are found in Eastern Australia.
Nurse sharks are not wanderlusts and tend to remain in the same place for years. So migration is not a trait of nurse sharks.
What is a nurse shark's habitat?
A nurse shark is an inshore bottom-dwelling species of fish. They reside at the bottom of deep coral reefs and are found in rocky places under the sea.
The younger ones tend to live in comparatively shallow waters than adults. They prefer shallow coral reefs, mangrove islands, and areas of seagrass beds. The crevices and holes found in these rocky places serve as their homes during the day.
Younger sharks also hide from predators by going inside these holes while adults go into deeper waters to rest. At night, they move from their shelter to prey on small fish found in the seabed of shallower areas.
Who do nurse sharks live with?
Nurse sharks are known to rest in groups. Their groups consist of around 2-40 sharks, and they rest by piling on top of each other. However, at night when they go on their hunting ventures, they prefer being alone.
How long does a nurse shark live?
Nurse sharks are comparatively less active than the species of other sharks. So they do well in captivity. Nurse sharks have an average lifespan of up to 25 years.
How do they reproduce?
The mating season of the species of nurse sharks lasts for short while starting from the end of June and continues till the end of July. They are ovoviviparous animals in nature.
A nurse shark lays eggs and these eggs hatch within the body of the female shark while it is pregnant. This is how they produce their newborns.
The female shark's ovaries are able to produce a new batch of eggs after 18 months making their reproduction cycle biennial.
They go through a gestation period of around six months and have an average litter size of 21-29 pups. A baby nurse shark is about 8-12 in (20-30 cm) in length and at the time of birth, they are fully developed.
What is their conservation status?
The conservation status of nurse sharks depends on different continental waters. At some places they are regarded as fishes of the Least Concern and at the others, their population is under threat.
For example, in the United States and the Bahamas, nurse sharks are considered as a species of the Least Concern but in the coastal areas of Central America and South America and around the area of the Caribbean Sea these fish are under direct threat of some fisheries.
So this species is considered to be a Near Threatened species in this part. Some species of nurse shark, such as the shorttail nurse sharks are even Critically Endangered, according to the IUCN.
Nurse Shark Fun Facts
What do nurse sharks look like?
The nurse shark (Ginglymostoma cirratum) is a slow-moving huge fish that can measure up to 9.7 ft (3 m). They have a broad, round head and a phenomenally strong jaw.
The jaws are filled with tiny serrated teeth. Nurse shark teeth act as their defense to protect themselves. The mouth is present right at the front of the head.
Two fleshy extensions are present around the nasal openings which are known as barbels. Barbels help to locate and detect their prey.
Their body is wide and has a short snout. The body of a nurse shark is made of smooth skin. It consists of a pectoral fin that is round in shape, two dorsal fins that are also round in shape, and an elongated caudal fin.
Their body color varies from brown being the most common color to being gray or even yellowish. Young nurse sharks have spots on their body that gradually fade away.
How cute are they?
Nurse sharks are huge fish. They move very slow when they aren't hunting and are harmless to humans who mean no harm. Their personality is quite friendly and they are complete goofs of the ocean. For this reason, biologists and underwater researchers find this species of shark adorable and social unlike the more harmful species of sharks.
How do they communicate?
Like any other species of shark, nurse sharks are also incapable of making any noise. So they utilize body language to communicate with each other. Sharks have the ability to feel underwater vibration. They use this ability to detect the location of their prey or mate.
How big is a nurse shark?
The average length of an adult nurse shark ranges from 7.5-9.7 ft (2.2-3 m). The highest length of this shark species that has ever been recorded is 14 ft (4.3 m).
Length of newborn nurse sharks ranges from 8-12 in (20-30 cm). They are comparatively smaller than the sharks of other species like the lemon sharks or the tiger sharks.
How fast can a nurse shark swim?
Nurse sharks are known as the 'couch potatoes of the sea'. This is because, among all the species of shark, the nurse shark is one of the slowest swimmers in the ocean.
A nurse shark is observed to spend most of his time lying at the bottom of the seafloor where they go to rest. But they can swim with good speed when they are out to hunt at night.
At that time a nurse shark attains a speed of 25 mph (40 kph). Other than that their swimming speed drops to a mere 1.5 mph (2.4 km/h).
How much does a nurse shark weigh?
A fully grown adult nurse shark weighs around 200-330 lb (90.7-150 kg)
What are their male and female names of the species?
There is no difference between the names of a male and a female shark species. However, nurse sharks in the Caribbean waters are known with a common name called tiburon gato or catsharks.
What would you call a baby nurse shark?
A baby nurse shark is generally referred to as a pup.
What do they eat?
Nurse sharks are carnivorous in nature. They are nocturnal predators who come up to the seafloor at night to hunt. Their diet mainly includes shallow water small fish, shrimp, octopus and squid, sea urchin, clamp, corals and more. They vacuum up their food very quickly using strong suction power.
Are they dangerous?
Sharks are dangerous and can even prey on humans if they feel threatened. The nurse shark is no exception. Despite being peaceful in nature, they can still turn aggressive when they detect threats around them and when they get feared.
At this time they will try to attack and bite you which can result in fatality. However, a nurse shark attack is very uncommon and unheard of. The reason behind this can be the low and distributed population of these fishes.
Would they make a good pet?
It is unusual for a human being to try and pet a shark. When these sharks go into adulthood, they become huge. So home aquariums cannot accommodate the sharks in them.
Even if, somehow, arrangements of petting a nurse shark are made, it can turn out to be pretty costly. Petting a shark can also cause harm as they are carnivorous fishes. So petting a nurse shark is not recommended rather they tend to be happier in the wild where they belong.
Did you know...
The tail fin of nurse sharks is exceptionally large. They account for a quarter of the entire body length of a nurse shark. Due to this large tail, nurse sharks can move quickly using less energy.
Nurse Sharks and Humans
Humans and nurse shark interaction is quite common since nurse sharks live in shallow waters. Many divers have encountered nurse sharks swimming slowly in shallow waters.
These sharks are quite tolerant of human beings until they detect any major threat from them. Then the sharks become aggressive and try to attack. Some snorkelers and swimmers even ran into a nurse shark while swimming but they did not cause any harm.
Sometimes they grabbed these sharks by their tails or dorsal fins. Therefore, this species of carpet sharks are friendly to human beings until they are provoked.
Naming the Nurse Shark
It is very unusual to attach the term nurse to a species of fish as dangerous as a shark. There are a number of theories that have sprung up to try and give a justified and meaningful explanation of the name.
Two theories gain the most popularity. The first theory is that the sucking sound that a nurse shark makes while it hunts and feeds on its prey.
This reminded the sailors of nursing infants and therefore the term nurse is added to its name. The other theory that gained some attention is the word nurse is a corrupted form of the word 'nusse' that was again derived from the word 'huss'.
Huss is an archaic name given to a family of unrelated bottom-dwellers. So they became popular as nurse sharks.
The scientific name of a nurse shark, Ginglymostoma cirratum, also has a reference and meaning. It comes from the mixture of Latin and Greek words that means, 'curled hinged mouth' that somehow tries to describe the appearance of the fish.
Here at Kidadl, we have carefully created lots of interesting family-friendly animal facts for everyone to discover! Learn more about some other fish including herring facts and fluke fish facts.
You can even occupy yourself at home by drawing one on our nurse shark coloring pages.