This week we’re taking a look at Nurse Sharks! This species of slow-moving bottom dwelling shark is best known for snuggling together at night.  

There is debate around the origin of the common name ‘Nurse Shark’. Some people believe it may derive from the sucking sound they create when they are searching for their prey in the sand (resembling that of a baby feeding on milk), whilst other theories suggest it comes from the Old English word for ‘sea-floor shark’, hurse.

As bottom dwellers, Nurse Sharks use a special method of respiration called ‘buccal pumping’. In essence, this method uses the cheek muscles to draw water into the mouth and force it out again over the gills. This keeps the gills oxygenated even when the shark isn’t swimming. Some species, like Hammerheads, have to keep swimming continuously in order to supply oxygen to their gills, otherwise they would suffocate. The buccal pumping method allows Nurse Sharks to live a more sedentary life resting on the sea floor during the day and being more active at night. Another species that uses this technique is the Angel Shark – check out our Angel Shark conservation work here.

Nurse Sharks are also recognisable for their ‘barbels’: long, fleshy appendages which hang down off their snout and are thought to provide a sense of touch when trying to locate their prey along the seafloor.

Their most unique behaviour is that Nurse Sharks tend to sleep together, side by side, during the day when they are resting. These groups can pile up to 40 sharks! Scientists aren’t too sure why they do this, but it might be for protection from predators.

Tawny Nurse Shark

Scientific Name: Nebrius ferrugineus

*Greek: Nebri, -idos = skin of a fawn, This likely makes a reference to Nurse Sharks having softer skin than most other sharks.

Latin, ferruginous – refers to the colour of iron-rust

Family: Ginglymostomatidae

*Greek: ginglymus = hinge; stoma = mouth. Both of which presumably refer to how the corner of the mouth has a hinged appearance.

Maximum Size: 3.08m  (total maximum length)

Diet: Bottom dwelling animals such as stingrays, squid, crabs, snails, urchins, lobsters.

Distribution: Shallow waters of the western Atlantic and eastern Pacific.

Habitat: Juveniles spend time in shallow reefs, mangrove habitats and seagrass beds. Large adults migrate to deeper water.  

Conservation Status: This species is caught for meat, fins, liver oil, leather and fishmeal.

IUCN Red List Status: Vulnerable.

---

Image Credits: Laura Corbe