Tag Archive: sharks


TAXONOMY
Kingdom: Animalia
Phylum: Chordata
Class: Elasmobranchii (sharks and rays)
Subclass: elasmobranchii (No swim bladders, five to seven pairs of gill clefts opening individually to the exterior, rigid dorsal fins, and small placid scales).
Order: Carcharhiniformes (Ground sharks)
Family: Triakidae (Houndsharks are distinguished by possessing two large spineless dorsal fins, an anal fin, and oval eyes with nictitating eyelids. They are small to medium in size, ranging from 37 centimetres (15 in) to 220 centimetres (7.2 ft).

Genus/species: Triakis semifasciata

GENERAL CHARACTERISTICS: Grey to bronze-grey upper body with dark saddles and dots and a light ventral (bottom) surface. Short, broadly rounded snout. First dorsal fin is moderately large and its origin is over the pectoral fins inner margins. Second dorsal fin is nearly as large as the first one. Anal fin much smaller than the second dorsal fin. Pectoral fins broadly triangular. Max length : 198 cm (78 in).

Leopard Shark 2959038532_163d96da28_o

DISTRIBUTION/HABITAT: Common from Oregon state to Baja California,Mexico. Prefers sandy and rock-strewn substrate near rocky reefs. Most commonly in enclosed muddy bays, including estuaries and lagoons, typically at less than 3.7 m or 13 ft depth, but ranges to 91m or 300 ft.

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DIET IN WILD: Fishes (especially northern midshipman, sanddab, shiner perch, bat rays and smoothhounds), siphons of clams, crustaceans such as crabs and shrimp. Feeds heavily on fish eggs (herring, jacksmelt and topsmelt) attached to rocks and plants.

 The leopard shark captures prey by expanding its buccal cavity to create a suction force, which is facilitated by its labial cartilages swinging forward to form the mouth into a tube. Simultaneously, the shark protrudes its jaws forward to grip the prey between its teeth.

REPRODUCTION: Ovoviviparous. Litters 4–29. Young average 21 cm or 8 in at birth.

PREDATORS: Can live to at least 30 years. These good eating sharks are a very popular as a sport “fish.” Also preyed upon by other sharks.

Leopard Shark 8415453774_b665c7a08e_o

IUCN Least Concern

REMARKS: In San Francisco Bay, leopard sharks tend to remain in the Bay throughout the year, with some emigration during fall and winter. Not dangerous.

Fossils of leopard sharks have been discovered in deposits dated to more than 1,000,000 years old in southern California.

References

Peterson Field Guides, Pacific Coast Fishes, Eschmeyer and Hearld 1983

WordPress Shortlink http://wp.me/p1DZ4b-Yt

flickr https://www.flickr.com/photos/cas_docents/26397788159/in/album-72157608359804936/

fishbase www.fishbase.org/summary/2543

Ferry-Graham, L.A. (1998). “Effects of prey size and mobility on prey-capture kinematics in leopard sharks Triakis semifasciata” (PDF). Journal of Experimental Biology. 201 (16): 2433–2444. PMID 9679105.

Probably More Than You Want To Know About The Fishes Of The Pacific Coast, Milton Love 1996 Really Big Press p 60-61

TAXONOMY
Kingdom: Animalia
Phylum: Chordata
Class: Elasmobranchii (sharks and rays)
Order; Orectolobiformes (Carpet sharks) Most carpet sharks feed on the seabed in shallow to medium-depth waters and have ornate patterns reminiscent of carpets.
Family: Stegostomatidae (Zebra sharks)

Genus/species: Stegastoma fasciatum ( juvenile)

GENERAL CHARACTERISTICS: S. fasciatum has a cylindrical body with a large, slightly flattened head and a short, blunt snout and is yellow-brown with dark brown spots. Young less than 70 cm (2,3 feet) in length are black with yellow bars. Adults have longitudinal skin ridges. The head has 5 small gill slits, the last three behind pectoral fin origin; nostrils close to front of snout, with short barbels.  Pectoral fins are large and broadly rounded and body has a long caudal fin, almost as long as the rest of the body.

Length up to 354 cm (11.7 feet) 

Zebra Shark 16235954845_08c3bb04f1_k

DISTRIBUTION/HABITAT: Tropical marine. Indo-West Pacific. Found near coral reefs with sandy bottoms and remain at the reef at where they were hatched or reefs that are closely connected to their natal area.

Depth range 0 – 63 m (206 feet).

DIET IN THE WILD: Feeds mainly on mollusks, but also small bony fishes, crustaceans (crabs and shrimps) and sea snakes.

REPRODUCTION: Oviparous S. fasciatum has large purplish-black eggs or dark brown egg cases with longitudinal striations.

Lifespan: Ave. 25 years. 

CONSERVATION: IUCN Red List; Vulnerable (VU)     Decreasing numbers secondary to heavily fished shallow coral reef habitat throughout all its range except Australia.

Remarks: Like other bottom dwelling sharks, it can pump water across its gills through its mouth, which allows the shark to respire while stationary. 

It was tank bred at the Shedd Aquarium.

References

California Academy of Sciences Reef Lagoon 2016

fishbase: www.fishbase.org/summary/5374

IUCN Red List  www.iucnredlist.org/details/41878/0

Arkive  www.arkive.org/leopard-shark/stegostoma-fasciatum/

Animal diversity web http://animaldiversity.org/site/accounts/information/Stegostoma_fasciatum.html

Marinebio marinebio.org/species.asp?id=56

Ron’s flickr https://www.flickr.com/photos/cas_docents/16235954845/

Ron’s WordPress shortlink  http://wp.me/p1DZ4b-1rb

TAXONOMY
Kingdom: Animalia
Phylum: Chordata
Class:Class: Chondrichthyes (sharks and rays)
Order: Carcharhiniformes (Ground sharks)
Family: Carcharhinidae (Requiem sharks eg migratory, live-bearing sharks of warm seas)

Genus/species: Carcharhinus melanopterus

GENERAL CHARACTERISTICS:
All fins tipped with black, the large dorsal fin with a white band beneath the black tip, conspicuous white bands along flanks, sometimes edged with black. Otherwise, yellowish-tan above, white below.
Length up to 2 m (6.5 ft) long and weight up to 13.6 kg (30 lbs)

Carcharhinus melanopterus2979831615_73451da081_b

DISTRIBUTION: Subtropical from Red Sea and East Africa to the Hawaiian Islands and the Tuamoto Archipelago. Also enters the Mediterranean from the Red Sea (via the Suez Canal). Prefers inshore coral reefs and the intertidal zone. Has been observed in mangrove areas and fresh water, traveling in and out with the tide.

DIET IN THE WILD: Teleost fishes sea snakes. Predation upon other elasmobranchs was rare.

REPRODUCTION: C. melanopterus is viviparous, incubating young for up to 16 months, producing 2–4 pups per litter. In a fashion not uncommon in sharks, the male takes the female’s pectoral fin in his teeth and the two mate belly to belly.

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PREDATORS: Preyed upon by other sharks as well as large groupers. Average lifespan c. 12 years

CONSERVATION: IUCN Near threatened (NT) 2015-4
The Blacktip Reef Shark is not a target of major fisheries, but is regularly caught by inshore fisheries in India and Thailand. It is caught for human consumption, fishmeal, and their fins enter the oriental sharkfin trade, for sharkfin soup. Their livers are also sought as a rich source of oil.

REMARKS: Often hunt in packs, driving prey into a tight ball and then attacking the ball in a feeding frenzy, even leaping out of the water. Its distinctive appearance and active swimming habit make it a favorite specimen for aquariums. It has been known to bite people wading in shallow water and is aggressive towards spear fishers.

References

Californiua Academy of Sciences Steinhart Aquarium Reef Lagoon 2-2-16

References

Californiua Academy of Sciences Steinhart Aquarium Reef Lagoon 2-2-16

Ron’s flickr https://www.flickr.com/photos/cas_docents/2979831615/in/album-72157627919810858/

Ron’s WordPress shortlink  http://wp.me/p1DZ4b-1DM

arkive  www.arkive.org/blacktip-reef-shark/carcharhinus-melanopte…

fishbase www.fishbase.org/summary/SpeciesSummary.php?&genusnam…

IUCN: www.iucnredlist.org/details/39375/0

fishbase www.fishbase.org/summary/SpeciesSummary.php?&genusnam…

TAXONOMY
Kingdom: Animalia
Phylum: Chordata
Class: Elasmobranchii (sharks and rays)
Order: Carcharhiniformes (Ground sharks; characterized by the presence of a nictitating membrane over the eye, two dorsal fins, an anal fin, and five gill slits.)
Family: Scyliorhinidae (Cat sharks; elongated cat-like eyes and a patterned appearance, ranging from stripes to patches to spots)

Genus/species: Cephaloscyllium ventriosum

SwellShark14479061579_a24e4ac80e_b

GENERAL CHARACTERISTICS: Maximum length 3.2 ft. Stout body with flat, broad head; snout short; mouth huge, proportionally larger that the great white shark (Carcharodon carcharias). Teeth are at front of jaws with dagger-like central point and 1-2 small points on each side; two dorsal fins: first much larger, with origin over pelvic fins, second dorsal fin considerably smaller than first, its origin over origin of anal fin. The body is light brown with dark patches covered with black dots.

DISTRIBUTION/HABITAT: Central California to southern Mexico; also reported near central Chile.
Found in rocky reefs and kelp forests, from surface to 460 m (1500 ft), in temperate and subtropical waters.

DIET IN THE WILD: Nocturnal; feeds on crustaceans and fishes, often blacksmith. Lie-in-wait predator that sits on the bottom with wide-open mouth, ready to ambush unsuspecting prey. (slowly opens jaws; lies in wait for prey to swim inside).

REPRODUCTION: Oviparous; female lays amber-colored egg cases that hatch in 8–10 months. Egg case (“mermaid’s purse”) is 9 – 13 centimeters (3.5 – 5 inches) long, 3 – 6 centimeters (1 – 2.3 inches) wide. Young have enlarged toothlike denticles on the back that help them break through egg cases. Pups measure 14 – 15 centimeters at birth; immediately feed on their own

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Swell Shark egg Case IMG_0322

PREDATORS:  If caught it is, usually it will be released because its flesh is of poor quality. Embryos may be eaten by snails that bore through egg cases.   Life span: 25 or more years.

CONSERVATION: IUCN Red List: least concern species

REMARKS: Hides in caves and crevices during normal aquarium hours. the day, and so is often not to be seen during aquarium hours. Common and specific (ventriosum = “largebelly”) names come from its ability to take in water that makes it appear up to twice as large as its normal size, a difficult meal for predators to bite or to remove from a crevice. If caught and brought to the surface, it can swell its body with air.

When caught by fishermen and brought out of water, the release of gulped water/air can cause the swell shark to “bark”.

Occurs in aggregations while resting, sometimes piled one on top of the other.

Swell Shark 3426936973_ee6379d9fb_b

Southern California Coast Kelp Exhibit CC14, Tidepool young with egg cases.

References

 Wordpress shortlink wp.me/p1DZ4b-XL

 flickr www.flickr.com/photos/cas_docents/14479061579/in/set-7215…

fishbase www.fishbase.org/summary/802

 Marine bio.org marinebio.org/species.asp?id=383

 eol eol.org/pages/208742/details

Sean Donahoe, CAS docent, materials from the Naturalist Center and collaborated with Docent Program staff document.

Works Cited

1. Carwardine, M. 2004. Shark. Firefly Books. Buffalo. 168 p.

2. Michael, S.W. 1993. Reef Sharks and Rays of the World: A guide to their

identification, behavior, and ecology. Sea Challengers. Monterey. 107 p.

3. Parker, S. and Parker, J. 1999. The Encyclopedia of Sharks. Firefly Books.

Buffalo. 192 p.

4. Ebert, D.A. 2003. Sharks, Rays, and Chimeras of California. University of

California Press. Berkeley/Los Angeles. 284 p.

5. Springer, V.G. and Gold, J.P. 1989. Sharks in Question. Smithsonian Institution

Press. Washington, D.C. 187 p.

 

 

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