The spot-tail shark, or sorrah shark (''Carcharhinus sorrah''), is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

requiem shark Requiem sharks are sharks of the family Carcharhinidae in the order Carcharhiniformes. They are migratory, live-bearing sharks of warm seas (sometimes of brackish or fresh water) and include such species as the tiger shark, bull shark, le ...

, in the

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

Carcharhinidae, found in the tropical Indo-West Pacific Ocean between latitudes 31°N and 31°S, from the surface to a depth around . This shark grows to about . It is fished commercially over much of its range and the

IUCN The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of natu ...

considers it to be

near threatened A near-threatened species is a species which has been categorized as "Near Threatened" (NT) by the International Union for Conservation of Nature as that may be vulnerable to endangerment in the near future, but it does not currently qualify fo ...

Description

The spot-tail shark is a spindle-shaped fish growing to about . It has a fairly long, pointed snout and moderately large eyes. The first dorsal fin is large and curved, while the second dorsal fin is small and low. The back and sides are grey and the belly white, and a long white streak is on the flank. This species can be distinguished from other requiem sharks found in tropical waters by the distinctive black tips to the second dorsal fin, the pectoral fins, and the lower lobe of the caudal fin. A ridge over the spine extends from the first to the second dorsal fin and a pit just in front of the upper lobe of the caudal fin. The upper teeth are serrated, oblique, and triangular. The

Australian blacktip shark The Australian blacktip shark (''Carcharhinus tilstoni'') is a species of requiem shark, in the family Carcharhinidae, endemic to northern and eastern Australia. Favoring the upper and middle parts of the water column, it can be found from the i ...

(''C. tilstoni''), which occupies a similar range, has similar black tips to the fins, but additionally has a black tip to its first dorsal fin. It lacks the ridge between the two dorsal fins and its upper teeth are also different, being slender, upright, and pointed.

Distribution

The spot-tail shark is found in the tropical Indo-Pacific on continental and insular shelves commonly to a depth around , but possibly as deep as . Its range extends from the East African coast, Madagascar, and the Red Sea to India, Malaysia, China, the Philippines, and northern Australia.

Biology

The spot-tail shark spends the day near the seabed and the night at the surface, most frequently around reefs. It is a

predator Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill th ...

and feeds on bony fish such as

bonito Bonitos are a tribe of medium-sized, ray-finned predatory fish in the family Scombridae – a family it shares with the mackerel, tuna, and Spanish mackerel tribes, and also the butterfly kingfish. Also called the tribe Sardini, it consists of ...

and

sea bass Sea bass is a common name for a variety of different species of marine fish. Many fish species of various families have been called sea bass. In Ireland and the United Kingdom, the fish sold and consumed as sea bass is exclusively the European ba ...

, cephalopods, and crustaceans. The spot-tail shark is viviparous with a yolk-sac placenta, giving birth once a year to a litter of one to eight live young. The gestation period is 10 months and the pups measure about at birth. The young develop in shallow inshore waters. They grow rapidly at first, increasing in length by about during their first year, but growth slows down thereafter. Females reach sexual maturity at two to three years and live for a maximum of seven years, while males live up to five years.

Status

The spot-tail shark is caught by line and gillnet in many parts of its range by small-scale commercial fisheries. The flesh is used for food, the liver for vitamins, the fins for

shark fin soup Shark fin soup is a traditional soup or stewed dish served in parts of China, Taiwan, and Southeast Asia. The shark fins provide texture, while the taste comes from the other soup ingredients. It is commonly served at special occasions such as ...

, and the offal for

fish meal Fish meal is a commercial product made from whole wild-caught fish, bycatch and fish by-products to feed farm animals, e.g., pigs, poultry, and farmed fish.R. D. Miles and F. A. Chapman.FA122: The Benefits of Fish Meal in Aquaculture DietsFisheri ...

. The

has listed this shark as being

, as it suffers from overfishing throughout much of its range and many populations seem to be in decline. The fisheries in northern Australia are relatively well managed.

References

External links

* * {{Taxonbar, from=Q210052 Carcharhinus Fish described in 1839