November 2, 2020
AZ Animals Staff
Nurse Shark Facts
- Main Prey
- Squid, Fish, Octopus
- Warm waters and tropical coastal regions
- Human, Bull Shark, Tiger Shark
- Average Litter Size
- Favorite Food
- Commonly found in Central American waters!
Nurse Shark Physical Characteristics
- Skin Type
- Top Speed
- 25 mph
- 20-25 years
- 90-150kg (198-330lbs)
“Nurse sharks have smoother skin than most sharks. It feels like sandpaper.”
Sometimes called the couch potatoes of the sea, nurse sharks are large, peaceful fish that slowly drift along the bottom of the ocean in shallow water, sucking up food as they go. They hunt alone at night but return to the same comfortable resting place during the day where they enjoy dozing in piles. Although their habitat is alongside humans, these fish are rarely harmful; they will only bite if startled or provoked. These gentle sharks are quite comfortable in zoo aquariums and can live up to 25 years in captivity.
5 Nurse Shark facts
- Unlike many other shark species that must swim at all times to breathe, the nurse shark uses the buccal pumping method to breathe. They use their oral muscles to pull water into their mouths to oxygenate their gills, allowing them to stay still and even sleep.
- These sharks don’t pose any threat to humans unless they are disturbed. In fact, many people swim right by these sharks without ever knowing they were there.
- When a school of nurse sharks finds a comfortable resting place, they return there each day after hunting rather than migrating like many other fish species.
- They use their pectoral fin to “walk” across the ocean floor, and females will sometimes bury their pectoral fins in the sand to avoid the mating advances of males.
- Rather than chasing their prey and catching it in a flurry of chomping teeth like other sharks, this species swims just above the ocean floor and suck up their food like a vacuum cleaner. After sucking their food into their mouths, they use rows of serrated teeth to crush up their food before swallowing.
Nurse Shark Scientific name
The nurse shark is in the Ginglymostomatidae family and the Chondrichthyes class. Its scientific name, Ginglymostoma cirratum, is a mix of Greek and Latin and means “curled, hinged mouth.” This name is rather fitting because this shark always looks like he’s puckering up. Since this species of shark prefers to stay close to the ocean floor, many scientists believe its name came from the Old English word “hurse,” which means sea-floor shark.
Nurse Shark Appearance
The nurse shark has a wide body and a short snout with a small, rectangular mouth. They have two sensory organs called barbels that grow down from their upper lip. These barbels help them find small fish and crabs hiding in the sand.
This species of sharks look a bit different than many of their more dangerous cousins. Their thick skin is smoother than most other sharks, and their dorsal fin is rounded rather than the customary sharp dorsal fin that is commonly associated with other species. Their color sets them apart from the others as well — they are tawny brown rather than grey.
These sharks grow to about 7.5 to 9 feet long and weigh between 150 and 300 pounds. The largest nurse shark on record to date is 14 feet long, which is more than two times longer than the average man is tall. Unlike more dangerous shark species, their dorsal fins are rounded rather than sharp. They also have long tails, which can make up about a quarter of their total length.
Nurse Shark Behavior
The nurse shark is a solitary, nocturnal hunter, but if you see one during the day, it will probably be resting in a pile of other similarly sized sharks. These sharks don’t migrate; when they finish hunting for the night, they will return to their favorite cave or coral reef to rest.
Nurse Shark Habitat
Nurse sharks like warm, shallow water and can be found all across the eastern part of the Pacific Ocean and the western part of the Atlantic Ocean. They live in close proximity to human activity and, while they are not usually aggressive, can bite in self-defense if humans encroach on their territory.
Nurse Shark Population
There’s no record of the nurse shark population worldwide, though their numbers have been reduced in certain areas due to previous overfishing for their skin and oil. Since humans no longer routinely hunt these sharks, the species as a whole is thriving and nowhere near extinction.
Nurse Shark Diet
Small fish, shellfish, shrimp and squid are some of the nurse shark’s favorite foods, though they will also eat algae and coral from time to time. Since they hunt at night, it is believed that they eat fish that are resting, making those fish slow enough to be easy prey.
Nurse Shark Predators and Threats
The nurse shark isn’t hunted regularly by any specific predators, but it can make an easy meal for larger fish such as tiger sharks or lemon sharks. This species of shark is not a threatened or endangered species.
Nurse Shark Reproduction, Babies and Lifespan
When a nurse shark wants to mate, the male will bite the female’s pectoral fin to hold her in place for the mating process. Studies have shown that this species is unique in its reproductive process compared to other sharks because more than one male can fertilize the same litter.
This species of sharks is ovoviviparous, meaning that the female carries the fertilized eggs inside her to incubate. When the 6-month incubation period comes to an end, she gives birth to a litter of about 25 live pups. These pups are roughly 8-12 inches in length when they are born. After giving birth, it takes the female 18 months to produce eggs and go through the reproductive cycle again.
Nurse Sharks in Zoos
Nurse sharks do well in captivity, possibly because they are less active than other shark species. Since they don’t need to stay swimming to breathe, they are less bothered by smaller living spaces than their more active cousins. The average lifespan for a nurse shark in captivity is up to 25 years.
You can find them at Point Defiance Zoo & Aquarium in Tacoma, Washington; Omaha’s Henry Doorly’s Zoo & Aquarium in Omaha, Nebraska; and the National Aquarium in Baltimore, Maryland to name just a few.View all 12 animals that start with N
Nurse Shark FAQs (Frequently Asked Questions)
Is it safe to swim with nurse sharks?
Swimming with nurse sharks is relatively safe, but that doesn’t mean there’s no risk involved at all. Even though these slow-moving sharks are docile, you must remember that they are still wild animals and may attack if they feel threatened.
Can I pet a nurse shark?
This species of shark is usually harmless to humans, but that doesn’t mean you should try to pet them. Their mouths are small, but if you startle or step on one, they will use their sharp, serrated teeth to defend themselves.
Has a nurse shark ever killed a human?
Though their teeth are sharp and can do some damage, there is no record of a nurse shark attack resulting in the death of a human. These sharks are mostly docile and will only bite if provoked.
Are nurse sharks carnivores?
Yes, nurse sharks are carnivores. Their diet consists of small fish, shellfish and squids. Though a fisherman will occasionally find algae in their stomachs, scientists believe the sharks simply suck the algae up alongside their prey rather than intending it to be a source of food.
Are nurse sharks blind?
No, nurse sharks are not blind, but there are two species in the carpet shark order who are. All carpet sharks have similar features, so it is easy to mistake one species for another.
Are nurse sharks grey?
No, nurse sharks are tawny brown in color. Though Australia’s sand tiger shark is sometimes called a grey nurse shark, the two species have an entirely different appearance and temperament. They also live in different areas of the world, with the nurse shark living near the southern United States and the sand tiger shark living off the coast of Australia.
- Mark Mancini for Mental Floss, Available here: https://www.mentalfloss.com/article/559319/nurse-shark-facts
- Aquaviews, Available here: https://www.leisurepro.com/blog/explore-the-blue/carpet-bunch-7-families-carpet-sharks/
- How Stuff Works, Available here: https://animals.howstuffworks.com/fish/sharks/nurse-shark2.htm
- Wikipedia, Available here: https://en.wikipedia.org/wiki/Sand_tiger_shark