white mullet Mugil curema

Mugil curema

white mullet

Type Locality

Brazil, Martinique, and Cuba (Valenciennes 1836).

Etymology/Derivation of Scientific Name

Mugil curema, Greek derivation (Wood 1928:52).

Synonymy

Characters

Maximum size: 355-360 mm SL in the Atlantic (Martin and Drewry 1978).

Coloration: Larger specimens lacking dark longitudinal stripes on sides (Murdy 1983; Hubbs et al. 1991). Color above bluish, greenish, or olive with bluish reflections, and silvery elsewhere; opercle yellowish or golden, the color diffuse; pelvic and anal fins pale; caudal fin yellowish at base, pale centrally, with a dusky or dark margin; dorsal and pectoral fins dusky; axil of pectoral bluish black; peritoneum jet black; distinct bright gold or yellow spot behind opercle of individuals between at least 18-320 mm SL, but this color lost after preservation; gold pigment in iris restricted to spot above pupil, this usually remains obvious in preserved fish (Martin and Drewry 1978).

Counts: Usually 38 lateral line scales; total anal fin elements 12, larger specimens with 3 spines and 9 soft rays, small juveniles with 2 spines and 10 soft fins; lower limb of first gill arch with 25-60 gillrakers (Murdy 1983; Hubbs et al 1991; Miller 2005).

Body shape: Compressed, elongate (Martin 1978).

Mouth position: Mouth moderate, subinferior, oblique (Martin and Drewry 1978); lower jaw angular, with a prominent symphyseal knob (Hubbs et al. 1991).

External morphology: Soft dorsal and anal fins with many scales; adipose eyelid well developed in adults; scales cycloid (Hubbs et al 1991).

Internal morphology: All teeth simple; secondary mandibular teeth absent; no teeth on palate (Miller 2005); stomach muscular, gizzardlike (Hildebrand 1925).

Distribution (Native and Introduced)

U.S. distribution: Coastal species in temperate and tropical seas of the Western Hemisphere (Hubbs et al. 1991). Adults seem most abundant near Florida (Ross 1980).

Texas distribution: Inhabits most of the bays and estuaries of the state; individuals may also be found in the lower reaches of coastal streams (Hubbs et al. 1991). In south Texas, minimum temperature for activity of “large” juveniles and adults is between 10 – 12.5 degrees C (Moore 1976).

Abundance/Conservation status (Federal, State, NGO)

Habitat Associations

Macrohabitat: Known from hypersaline and fresh waters (Moore 1974; Ross 1980). Adults generally found in coastal waters including beaches, bays, lagoons, salt marshes, mangrove swamps and tidal rivers (Martin and Drewry 1978). Young abundant in bays and estuaries of Atlantic coast (Jacot 1920).

Mesohabitat: Adults prevalent in dirty water and over mud bottoms in the tropics and along the Gulf coast (Martin and Drewry 1978). Postlarvae and juveniles use brackish estuaries with organically rich substrates and move into oceanic waters in fall and winter (Anderson 1957; Ross 1980). Prejuveniles pelagic, marine, moving inshore at 17-25 mm SL (Anderson 1957); often remaining near inlets, on the south Texas coast (Moore 1974). In Texas, juveniles locally abundant in and near passes and inlets (Moore 1974; Martin and Drewry 1978). In Texas, a size class modally 63-68 mm TL entering bays along with prejuveniles beginning about May, leaving about October when temperatures drop (Gunter 1945). Gunter (1945) reported movements of all age groups suggested to be controlled by temperature, in Texas. Minimum temperature for activity of “large juveniles and adults ranges from 10-12.5 degrees C in winter, in south Texas (Moore 1976). Mugil curema collected at water temperatures of 19-36 degrees C, in Texas; adults were abundant only in salinities of 25-36 ppt (Moore 1974).

Biology

Spawning season: Spring – summer (Ross 1980). Spawning observed on April 25, in south Florida; temperature rise above 20 degrees C suggested as trigger to spring onset of spawning season (Anderson 1957). In Texas, near ripe and ripe females predominant in February – March, first spent females in April – May, few ripe females available for collection from June to September, a second influx of spent females in October – November (Moore 1974).

Spawning location: Seawater; offshore in the Gulf of Mexico (Caldwell and Anderson 1959), and in the Atlantic (Anderson 1957; Ross 1980).

Spawning behavior: Eggs pelagic (Anderson 1957); presumably located near or at surface (Martin and Drewry 1978).

Fecundity: Unfertilized eggs average 0.82 mm diameter; oil globule average 0.30 mm diameter; yolk appearing as unsegmented, opaque mass with little or no perivitelline space; oil globule pale yellow, located at top of yolk mass; surface of chorion with finely scratched or etched appearance; fertilized eggs average 0.90 mm diameter after 2 hours, hatching 40-42 hours after fertilization (Anderson 1957; Martin and Drewry 1978).

Age/Size at maturation: May mature at 1 year of age; in a spawning school, running ripe males averaged 189 mm SL, females 209 mm SL (Anderson 1957). In Texas, males may mature as small as 86 mm SL and females at 90 or 120 mm SL (Martin and Drewry 1978).

Migration: Prejuvenile movements consisting of migration from marine waters to estuarines and lagoons; in Texas, seasonal migration April – October, peaking in June or July (Moore 1974; Gunter 1945).

Longevity: 18.7 years, in the Gulf of Mexico (Aguirre et al. 1999).

Growth and Population structure: During 1^st year, growth estimated at 17 mm SL per month; individuals spawned in the fall estimated to reach about 70 mm SL by December. Non isometric patterns in body proportions including eye diameter, body depth, and head length affect mostly prejuvenile size classes, growth isometric after 30 mm SL (Anderson 1957).

Food habits: Odum (1968) reported that juvenile fish fed heavily upon a bloom of the dinoflagellate Kryptoperidinium obtained near the air-water interface, returning to a benthic diet of Spartina detritus particles, benthic diatoms and sediment particles with the cessation of the bloom. In Texas, both juvenile and adult stomachs contained similar items of sediment particles, detritus, diatoms, green algae, and blue-green algae, as well as similar proportions of each item (Moore 1974).

Phylogeny and morphologically similar fishes

Mugil curema lacks the dusky streaks along scale rows characteristic of M. cephalus; in south Texas, the axil of pectoral is bluish black, lighter than same for Mugil cephalus (Martin and Drewry 1978).

Host Records

Metacercarial stage Rhipidocotyle lepisostei (Trematoda: Bucephalidae; Hopkins 1954).

Commercial or Environmental Importance

Species not highly prized as food, but valuable as bait in the billfish sport fishery (Collins 1985).

References

Aguirre, A.L.I., M. Gallardo-Cabello, X.C. Carrara. 1999. Growth analysis of striped mullet, Mugil cephalus, and white mullet, M. curema (Pisces: Mugilidae), in the Gulf of Mexico. Fishery Bulletin 97(4):861-872.

Anderson, W.W. 1957. Early development, spawning, growth, and occurrence of the silver mullet (Mugil curema) along the south Atlantic coast of the United States. Fishery Bulletin of the Fish and Wildlife Service 57(119):397-414.

Caldwell, D. K. and W. W. Anderson. 1959. Offshore occurrence of silver mullet, Mugil curema, in the western Gulf of Mexico. Copeia 1959(3):252-253.

Collins, M.R. 1985. Species profiles: life histories and environmental requirements of coastal fishes and invertebrates (South Florida) – white mullet. U.S. Fish and Wildlife Service Biol. Rep. 82(11.39). U.S. Army Corps of Engineers, TR EL-82-4. 7 pp.

Cuvier, G., and A. Valenciennes. 1836. Histoire Naturelle des Poissons. Vol. II. Chez F.G. Levrault, Paris. 506 pp.

Gunter, G. 1945. Studies on Marine Fishes of Texas. Bull. Inst. Mar. Sci., University of Texas. 1:1-190.

Hildebrand, S.F. 1925. Fishes of the Republic of El Salvador, Central America. Bulletin of the Bureau of Fisheries 983:237-287.

Hopkins, S.H. 1954. The American species of trematode confused with Bucephalus (Bucephalopsis) haimeanus. Parasitology 44:353-370.

Hubbs, C., R. J. Edwards, and G.P. Garrett. 1991. An annotated checklist to the freshwater fishes of Texas, with keys to identification of species. The Texas Journal of Science, Supplement, 43(4):1-56.

Jacot, A.P. 1920. Age, growth and scale characters of the mullets, Mugil cephalus and Mugil curema. Transactions of the American Microscopial Society 39(3):199-229.

Martin, F.D., and G.E. Drewry. 1978. Development of Fishes of the Mid-Atlantic Bight. Vol. VI. Fish and Wildlife Service, Solomons, Maryland. 416 pp.

Miller, R.R. 2005. Freshwater Fishes of Mexico. University of Chicago Press, Chicago, Illinois. 490 pp.

Moore, R.H. 1974. General ecology, distribution and relative abundance of Mugil cephalus and Mugil curema on the south Texas coast. Contributions in Marine Science 18:241-255.

Moore, R.H. 1976. Seasonal patterns in the respiratory metabolism of the mullets Mugil cephalus and Mugil curema. Contributions in Marine Science 20:133-146.

Murdy, E.O. 1983. Saltwater Fishes of Texas. National Sea Grant College Program, Texas A&M University, College Station. 220 pp.

Odum, W. E. 1968. Mullet grazing on a dinoflagellate bloom. Chesapeake Sci. 9(3):202-204.

Ross, S.W. 1980. Mugil curema (Valenciennes), White mullet. pp. 780 in D. S. Lee et al., Atlas of North American Freshwater Fishes. N. C. State Mus. Nat. Hist., Raleigh, i-r+854 pp.

Wood, F.A. 1928. Greek fish names. The American Journal of Philology 49(1):36-56.