Indian mackerelRAG

Rastrelliger kanagurta
31.3 cm FL

Characteristic features:

  • 2 small keels on either side of caudal peduncle
  • Adipose eyelids covering front and rear of eye
  • 30–46 gill rakers on lower limb of the first gill arch
  • Gill rakers long and visible from side of head when the mouth is open
  • 5–6 dorsal and anal finlets
  • Head length equal to or less than body depth
  • Body moderately deep, its depth at posterior margin of opercle 4.3–5.2 times fork length
  • Large interdorsal space

Colour:

Blue-green above, sides silver with golden tint. Narrow horizontal stripes on upper sides, and a black spot near lower margin of pectoral fins. Dorsal fins yellow with black tip; pectoral and caudal fins yellowish; other fins dusky.

Size:

Up to 42.1 cm TL, maximum weight to at least 3.8 kg (Manacop 1995 in1).

Distribution:

Found in tropical waters of the Indo-West Pacific.

View FAO distribution map

Habitat:

An inshore pelagic species, occurring in coastal bays, lagoons and harbours. Found in depths between 20–90 m.

Biology:

Feeds on plankton, primarily larval crustaceans but also larval fishes. A common species occurring in large schools. Length at first sexual maturity varies by regions, in Indian waters it is estimated to be at 19.6 cm TL;2 between 17.5–19.5 cm in Malaysian waters3 and at 20.42 cm in the Gulf of Suez, Egypt.4 Other length at first sexual maturity estimates range between 17–21 cm TL.5,6,7,8 Age at first maturity is estimated at 1.1 years in the Gulf of Suez, Egypt.4 Two spawning seasons are believed to occur, the first from January to March and the second from August to October. Fecundity of varies between 28,542 to 123,760 eggs.2 Estimated maximum age is 4 years.9

Indonesian fisheries:

Caught mainly with encircling nets, purse seines, lift nets and bamboo stake traps.

Similar species:

Rastrelliger brachysoma
Short mackerel
Rastrelliger brachysoma
Rastrelliger brachysoma differs in having a deep body, its depth at posterior portion of opercle 3.7–4.3 times in fork length (vs. moderately deep, 4.3–5.2) and no black spot near lower margin of pectoral fins (vs. a black spot).

 

Rastrelliger faughni
Island mackerel
Rastrelliger faughni
Rastrelliger faughni differs in having gill rakers that are shorter than snout, not visible when mouth is open (vs. long and visible); 21–26 gill rakers on lower limb of first gill arch (vs. 30–46); bristles on longest gill raker few in number (30–55) (vs. many (100+ for 13 cm specimen)) and a slender body, its depth at posterior portion of opercle 4.9–6 times in fork length (vs. moderately deep, 4.3–5.2).

 

Scomber australasicus
Blue mackerel
Scomber australasicus differs in having teeth present on roof of mouth (palatine teeth) in single or double rows (vs. absent); first anal-fin spine stiff and strong (vs. thin, rudimentary); many oblique wavy dark lines along back and pearl white below with wavy, broken lines giving faintly speckled appearance (vs. narrow horizontal stripes on upper sides and silvery white below with a black spot near lower margin of pectoral fins) and 25–35 gill rakers on first gill arch (vs. 30–46).

External links:

FishBase
The IUCN Red List of Threatened SpeciesTM

References

1.
Jones S, Rosa H. Synopsis of biological data on Indian mackerel, Rastrelliger kanagurta, (Cuvier) 1817 and short bodied mackerel, Rastrelliger brachysoma (Bleeker) 1851. 1965;
2.
Arrafi M, Azmi Ambak M, Piah Rumeaida M, Muchlisin Z. Biology of Indian Mackerel, Rastrelliger kanagurta (Cuvier, 1817) in the Western Waters of Aceh. Iranian Journal of Fisheries Sciences. 2016;15(3):957–72.
3.
Pathansali D. Observations on the gonad maturity stages of female Rastrelliger kanagurta Cuvier. Proceedings Indo-Pacific Fisheries Council. 1967;12(2):116.
4.
Amin S, Mohd Azim M, Fatinah S, Arshad A, Rahman M, Jalal K. Population Parameters of Rastrelliger kanagurta (Cuvier, 1816) in the Marudu Bay, Sabah, Malaysia. Iranian Journal of Fisheries Sciences. 2014;13(2):262–75.
5.
Sudjastani T. Species of Rastrelliger in the Java Sea, their taxonomy, morphometry and population dynamics. University of British Columbia; 1974.
6.
Sousa MI, Gislason H. Reproduction, age and growth of the Indian mackerel, Rastrelliger kanagurta (Cuvier, 1816) from Sofala Bank, Mozambique. Revista de Investigação Pesqueira. 1985;14:1–28.
7.
Sivadas M, Nair PN, Balasubramanian KK, Bhaskaran MM. Length weight relationship, relative condition, size at first maturity and sex ratio of Indian mackerel Rastrelliger kanagurta from Calicut. Journal of the Marine Biological Association of India. 2006;48(2):274–7.
8.
Bhendarkar M, Sonone A, Sonawane S, Gajbhiye A. Length-weight relationship of Indian mackerel, Rastrelliger Kanagurta (Cuvier, 1817) off Southern coast of Maharashtra, India. Ecology, Environment and Conservation. 2014;20(3):1055–7.
9.
Mehanna SF. Population dynamics and fisheries management of the Indian mackerel Rastrelliger kanagurta in the Gulf of Suez, Egypt. Marine Scienes. 2001;12(1).