Scientific Classification

Common Name

leopard shark

Kingdom

Animalia

Phylum

Chordata

Class

Chondrichthyes

Order

Carcharhiniformes

Family

Triakidae

Genus Species

Triakis semifasciata

Fast Facts

Description

One of the most distinguishing features of this species is the bold dark bars draped across the dorsal surface. Additional dark spots are found along the lateral surfaces of the species. In adult specimens, the pectoral fins are broadly triangular. The anterior edge of the first dorsal fin appears behind the pectoral fins posterior edge. The caudal fin is elongate, and lacks a lower lobe altogether. This species is an active, strong swimming shark, often observed moving with an undulating motion. They are known to form large schools, occasionally aggregating with gray or brown smooth-hound sharks (Mustelus californicus and M. henlei) and piked dogfish (Squalus acanthias).

Male: External claspers located on the far underside of the body – forward of the caudal fin – distinguish males.

Size

Male: 150 cm (4.9 ft) max
Female: 180 cm (5.9 ft) max

Weight

19 kg (41.9 lbs.) max

Diet

The leopard shark is an opportunistic feeder, primarily preying upon benthic organisms along with the occasional littoral prey item. Invertebrates tend to dominate its diet. Diet includes crabs, shrimp, clams, octopus, bony fish (i.e. anchovies, herring), and cartilaginous fish (i.e. brown smooth-hound sharks [Mustelus henlei], guitarfish [Rhinobatos productus] and bat rays [Myliobatis californicus]). Additionally, the fry of various fish species (i.e. herring, topsmelt, jacksmelt, and midshipmen) are avidly consumed by the leopard shark.

Gestation

Species is ovoviviparous, without a yolk-sac placenta.
Clutch Size: 4 to 29 young

Sexual Maturity

Species is relatively slow growing - possibly requiring over a decade to reach maturity.
Male: 119 cm (3.90 ft)
Female: 110 to 129 cm (3.61 to 4.23 ft)

Life Span

Species has lived for 20+ years in zoological settings

Range

Eastern North Pacific: Oregon to Gulf of California and Mexico

Habitat

An abundant, temperate-water shark found in inshore and offshore continental littoral waters. Species is most common on or near the bottom from the intertidal zone to 4 meters in depth. Accordingly, the leopard shark is typically found in shallow enclosed muddy bays - usually entering as the tide rises and departing as the tide retreats. The species favors sand flats, mud flats, and rocky bottom areas near reef sites and kelp beds.

Population

Global: No data
Regional: In certain Californian waters, increased pressure by spar and line-fishers may be leading to a decline in this species numbers.

Status

IUCN: Lower Risk/Conservation Dependent
CITES: Not listed
USFWS: Not listed

Fun Facts

1. This smallish shark species is generally considered non-threatening to humans; however, in 1955 an unprovoked attack on a diver in Trinidad Bay, California was recorded. The diver was not seriously injured.
2. Within a hollow bridge support structure located in San Francisco Bay, leopard sharks and piked dogfish have been observed engaging in a unique feeding strategy. The two sharks species will swim at the surface, with mouths open, in a counter-clockwise direction. At the same time densely packed schools of anchovies are gathered at the surface and will swim in a clockwise direction. While the sharks do not exhibit any specific hunting behavior or directed movements toward the oncoming anchovies, the sharks' posture and movement does result in ingestion of incidental prey (i.e. anchovies) which inadvertently swim into the open maw of the prowling sharks.
3. For more information about sharks & rays, explore the Sharks & Rays InfoBook.

Ecology and Conservation

Within a hollow bridge support structure located in San Francisco Bay, leopard sharks and piked dogfish have been observed engaging in a unique feeding strategy. The two sharks species will swim at the surface, with mouths open, in a counter-clockwise direction. At the same time densely packed schools of anchovies are gathered at the surface and will swim in a clockwise direction. While the sharks do not exhibit any specific hunting behavior or directed movements toward the oncoming anchovies, the sharks' posture and movement does result in ingestion of incidental prey (i.e. anchovies) which inadvertently swim into the open maw of the prowling sharks.

This shark species is very successful in zoological settings - where, not unexpectedly, it exhibits a strong tendency to stay in the benthic portions of an exhibit (although individual sharks will occasionally swim at midwater or at the surface).

Bibliography

Allen, Thomas B., The Shark Almanac. The Lyons Press, 1999.

Compagno, Leonard J.V., FAO Species Catalog, Vol. 4 Sharks of the World. United Nations Development Programme, Food and Agriculture Organization of the United Nations, Rome, 1984.

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