The Frilled Shark

The Frilled Shark  
      Chlamydoselachus anguineus

The frilled shark is a rare deep-water species. It poses no threat to humans due to the fact it lives where it is not likely to encounters people.


Identification:
The frilled shark's most identifiable feature is its long, eel-like body.

It is dark to light brown with darker fin edges. It has a long lower jaw and an enormous gape. It has six gill slits, the first of which goes continuously underneath the head.

Frilled sharks also only have one dorsal fin, located by the base of the caudal fin. Its caudal fin is almost completely an upper lobe.


Classification:
Kingdom : Animalia
Phylum : Chordata
Subphylum : Vertebrata
Class : Chondrichthyes
Subclass :  Elasmobranchii
Order : Hexanchiformes
Family : Chlamydoselachidae
Genus : Chlamydoselachus
Species : anguineus


Similar Species and Other Family Members:
There are speculations that the frilled sharks that live in South Africa are a different species, the South African frilled shark.


Reproduction:
Frilled sharks are ovoviviparous. We do not know their age of maturity. Frilled sharks are believed to give birth to 12 young. We do not know the frilled sharks' gestation period, however it has been estimated to a year or more due to the large size of the eggs.


Size:
 Male frilled sharks are believed to be sexually mature at 110 cm (3.6 feet), while females are sexually mature at about 135 cm (4.4 feet). The maximum reported length is 196 cm (6.4 feet).


Diet: 
Most of what the frilled shark feeds on is unknown. However, we do know that  it does eat squid and bony fish.


Teeth & Jaws:
Here is an image of frilled shark teeth. These teeth are perfect for snatching slippery prey, such as squid.

Habitat and Distribution:
Frilled sharks are found all over the world. They are most common at depths of 50-200 meters (160-660 ft), but they have been found as deep as 1,570 meters (5,150 ft).


Lifespan:
The lifespan is unknown. Since we cannot tag or track these sharks and they do not survive in captivity, we can't tell their life span.


Conservation Status:
According to the IUCN Red List of Threatened Species, the frilled shark is near threatened. They are generally a rare species. They are not actively fished, but a regular bycatch in many bottom trawl, midwater trawl, deep-set longline, and deep-set gillnet fisheries.



sources:
The Sharks of North America, Jose I. Castro
http://en.wikipedia.org/wiki/Frilled_shark
Sharkpedia, DK Publishing 
http://www.elasmo-research.org/education/ecology/deepsea-frilled_shark.htm
http://www.iucnredlist.org/details/41794/0
note: none of the images are mine

Another Shark Infographic...

Here is another infographic. It has some interesting facts for those of you that want to learn some more shark basics.

CITES Protects Sharks and Manta Rays

the oceanic whitetip, one of the newly protected species

This is big news in the world of sharks and rays conservation! CITES (the Convention on International Trade in Endangered Species of Wild Fauna and Flora), has announced that they have placed 5 endangered sharks and manta rays under CITES control. Under this, the oceanic whitetip (Carcharhinus longimanus), scalloped hammerhead (Sphyrma lewini), great hammerhead shark (Sphyrna mokarran), smooth hammerhead shark (Sphyrna zigaena) and the porbeagle shark (Lamna nasus), are protected, along with the manta ray (Manta birostris). From now on, all of the above species must be harvested with a CITES permit,  and evidence must be provided that they are harvested sustainably and legally.

credit to sharkangels.org

note: the oceanic white tip picture is not mine. credits to http://commons.wikimedia.org/wiki/File:Carcharhinus_longimanus_1.jpg

The Nurse Shark

The Nurse Shark
       Ginglymostoma cirratum


The nurse shark is a common shark species. It poses no threat to humans unless harassed or threatened.

Identification:
The nurse shark's most identifiable feature are it's conspicuous nasal barbels.

Color is variable, ranging from light yellowish to dark brown. The underside is a whitish-gray color. Neonatal nurse sharks have dark spots to aid camouflage.

 Another way to identify a nurse shark is by its caudal fin, which is almost completely an upper lobe.

Classification:

Kingdom : Animalia
Phylum : Chordata
Subphylum : Vertebrata
Class : Chondrichthyes
Subclass :  Elasmobranchii
Order : Orectolobiformes
Family : Orectolobidae
Genus : Ginglymostoma
Species : cirratum

Similar Species and Other Family Members:
There are no similar species or any other species in the family.

Reproduction:
Nurse sharks are an ovoviviparous. Male nurse sharks are sexually mature at 10 - 15 years, while females are sexually mature at 15 - 20 years. Nurse sharks give birth to 20 - 30 young about every other year. The gestation period is 5.5 months.

Size:
Males mature at 210 cm (7 feet), while females mature at 240 cm (8 feet). The maximum reported length is 430 cm (14 feet), but most experts agree that 430 cm is an exaggeration. A more realistic size estimate is 270 cm (9 feet).

Diet: 
The nurse shark feeds on crabs, lobsters, bivalves, squid, bottom-dwelling fish, octopus, shrimp, sea snails and sea urchins. They will also occasionally feed on stingrays. Most feeding is done at night, as nurse sharks often rest during the day.

Teeth & Jaws:
Here is an image of fossilized nurse shark teeth.

Habitat and Distribution:
Nurse sharks live on reefs and are found all throughout Atlantic reefs. They are found in tropical and sub-tropical waters of the east coast of the Americas and the west coast of Africa. This species is abundant all year long in Florida and the Caribbean.

Life Span:
The life span in the wild is unknown, but the oldest shark in captivity reached an age of 25 years.

Conservation Status:
According to the IUCN Red List of Threatened Species, the nurse shark is data deficient, meaning there is not enough data to determine a conservation status.

note: none of the images are mine

Shark Classification

Here is a quick thing on shark classification

Kingdom- Animalia

Phylum- Chordata

Subphylum- Vertebrata

Class- Chondrichtyes (cartilaginous fish)

Subclass- Elasmobranchii (upper jaw that is not fused to the braincase, no swim bladder, advanced electroreceptive system, a spiracle, skin with placoid scales, teeth modified placoid scales, and 5-7 separate slit-like gill openings on each side of the body: there are about 600 species of sharks, skates, and rays) 

Subclass- Plagiostomi (sharks and rays: upper jaw hung from skulls and different kind of blood)

Superorder- Selachimorpha (sharks: free upper eyelids, gill openings on the head, and pectoral fins separate from the side of the head)

Orders- Living sharks are split into 8 orders.

Shark Orders

Who has More to Fear: Sharks or Humans?

Here is a quick graphic on the truth about the shark human relationship. You'll be surprised at the numbers.....

Photo credit: Surfmeisters.com

Zebra Shark

The Zebra Shark
 Stegostoma  fasciatum




The zebra shark is know for its beautiful markings. There are no attacks on humans by a zebra shark on record.

Identification:
The easiest way to identify a zebra shark is by its unique markings. When it is young it has striped markings (hence the name zebra shark). As they get older, the stripes break into spots. Sometimes the spots will make the outline of the stripes, such as in the picture above. The coloration in juveniles is dark brown with tan or pale yellow stripes. Adult coloration is tan to pale yellow with black to dark brown spots. The zebra shark has 5 gills on each side. It has a broad elongated upper lobe of the caudal fin, and almost no lower lobe. It has small eyes and a small mouth with barbels on both sides of its mouth.

Classification:
Kingdom: Animalia
Phylum: Chordata
Subphylum: Vertebrata
Class: Chondrichtyes
Subclass: Elasmobranchii
Order: Orectolobiformes
Family: Stegostomatidae
Genus: Stegostoma
Species: fasciatum

Similar Species and Other Family Members:
The zebra shark is the sole member of the Stegostomatidae family. This shark is very distinctive, but as it is sometimes called a leopard shark, it is often confused with a cold water species which is also called the leopard shark (Triakis semifasciata).


Reproduction:
The zebra shark is oviparous (lays eggs). They will lay one to four eggs a brood. Their size at birth is around 25 centimeters (9.8 inches).

A young zebra shark

Size:
The maximum length of the zebra shark is 350 cm (11.5 feet).

Diet:
The zebra shark feeds on shellfish, crustaceans, and small fishes.

Teeth:

Zebra shark jaws

Habitat and Distribution:
The zebra shark lives in the warm waters of the tropical western Pacific and Indian Ocean.

Life Span:
The zebra shark's life span is believed to reach up to 30 years in the wild. The longest known life span in captivity is 25 years.

Conservation Status:
The zebra shark is listed as vulnerable.


A video of a zebra shark I took at
Discovery Cove.


Note: I do not own any of the still images.