Bluegrey carpetshark facts for kids
Quick facts for kids Bluegrey carpetshark |
|
|---|---|
 |
|
| Conservation status | |
| Scientific classification | |
| Genus: |
Brachaelurus
|
| Species: |
colcloughi
|
 |
|
| Where the bluegrey carpetshark lives | |
| Synonyms | |
|
Heteroscyllium colcloughi J. D. Ogilby, 1908 |
|
The bluegrey carpetshark (Brachaelurus colcloughi), also called Colclough's shark, is a rare type of carpet shark. It lives only in the shallow waters off northeastern Australia. This shark is one of only two living members of its family, Brachaeluridae.
The bluegrey carpetshark has a strong body and a wide, slightly flat head. Its eyes are on top of its head. It also has two long whiskers, called barbels, with skin flaps behind them. This shark has big pectoral fins and two dorsal fins that are not the same size. These fins are placed far back on its body. There is also a good amount of space between its anal fin and the base of its tail fin (caudal fin). This shark can grow up to 76 cm (30 in) long. Young bluegrey carpetsharks are black and white. As they get older, their colors fade, and adults become brownish.
When this shark is taken out of the water, it closes its eyes. This is similar to its relative, the blind shark (Brachaelurus waddi). The bluegrey carpetshark eats small creatures that live on the seafloor, like invertebrates, and bony fish. Female sharks give birth to 6 to 7 live pups. The International Union for Conservation of Nature (IUCN) says this species is Vulnerable. This is because it is rare and lives in areas where a lot of fishing happens. People sometimes catch them by accident or for the aquarium trade.
Contents
About the Bluegrey Carpetshark
Naming the Shark
The bluegrey carpetshark was first described in 1908. An Australian scientist who studied fish, named James Douglas Ogilby, gave it its scientific name. He named the shark after his friend, John Colclough. Ogilby based his description on two young male sharks found in Moreton Bay in Queensland, Australia.
For a while, there was some confusion about this shark's name and if it was different from the blind shark. This was sorted out when the Queensland Museum got new sharks to study. Other common names for this shark include blue-grey catshark and southern blind shark.
Where They Live
The bluegrey carpetshark is rare to uncommon. It lives along the northeastern coast of Australia. Most of these sharks are found from Gladstone, Queensland down to Ballina, New South Wales. Many sightings have been in Moreton Bay. There have also been a few reports from off the Cape York Peninsula. It's possible this shark lives in more places on the Great Barrier Reef.
This shark usually stays close to the shore. It prefers water less than 6 m (240 in) deep. However, it has been found as deep as 100 m (330 ft). They like soft, muddy or sandy bottoms. They have also been seen around shipwrecks.
What They Look Like
The bluegrey carpetshark has a strong body and a long, slightly flat head. Its snout (nose area) is blunt and looks like a wedge from the side. Its large eyes are oval-shaped and sit high on its head. Each eye has a strong ridge below it. Right behind and below each eye is a large, round hole called a spiracle.
The shark has two long whiskers, called barbels, in front of its nostrils. These barbels have a large flap of skin about halfway along their length. There are also skin flaps and grooves around the nostril openings. Two grooves connect these to its small mouth. The shark has 32 to 34 rows of teeth in its upper jaw and 21 to 29 rows in its lower jaw. Each tooth has a sharp, pointed center and two smaller points on the sides. It has five pairs of short gill slits. The fourth and fifth pairs are closer together than the others.
The pectoral and pelvic fins are wide and rounded. The pectoral fins are larger than the pelvic fins. The two dorsal fins have rounded tips and are placed far back on the body. The first dorsal fin starts above the pelvic fins. The second dorsal fin is smaller than the first. The anal fin is less than half the size of the first dorsal fin. Its back tip almost reaches the base of the caudal fin (tail fin). The tail fin is long and low, making up about a quarter of the shark's total length. It doesn't have a lower lobe, but it has a strong notch near the tip of the upper lobe.
The shark's skin is covered in tiny, smooth, non-overlapping dermal denticles. Adult sharks are grayish to golden brown on top and white underneath. They have faint darker patches and white spots on their dorsal fins. Young sharks have a striking pattern of big black marks on a white background. This species can grow up to 76 cm (30 in) long.
Life and Habits
How They Act
Just like the blind shark, the bluegrey carpetshark closes its lower eyelids when it's taken out of the water. It eats small creatures that live on the seafloor, like invertebrates, and bony fish.
How They Have Babies
This shark gives birth to live young. This is called aplacental viviparous. The young sharks lose their egg cases early on. They get their food from a yolk sac while they grow inside their mother. Females usually have litters of 6 to 7 young. When they are born, the baby sharks are about 17–18 cm (6.7–7.1 in) long.
Bluegrey Carpetsharks and People
The bluegrey carpetshark is harmless to humans. Sometimes, it gets caught by accident by commercial fishing boats. It can also be hooked by recreational anglers who fish for fun. A small number of these sharks are collected for people's private aquariums. This is because they are attractive, especially when they are young, and seem to do well in captivity.
The International Union for Conservation of Nature (IUCN) has listed this species as Vulnerable. This means they are at risk. They are vulnerable because they live in a specific type of habitat. Their range is small, and it's in an area where many people live and fish. Also, they don't seem to be very common.
See also
In Spanish: Tiburón ciego azulado para niños
