The white shrimp, Penaeus setiferus, was the first species of commercially important shrimp in the U.S., with the fishery for this species dating back to 1709 (Muncy 1984). P. setiferus is common in Florida waters and is generally found where water is less than 27 m deep (Muncy 1984). Antennae are significantly longer than body length, and may reach 2.5 - 3 times body length (Muncy 1984). Chromatophores in white shrimp are widely spaced, thus lending a lighter body color to this species than in either pink or brown shrimp. Overall body color is a bluish white, speckled with black, with pink-tinged sides. Pleopods are often marked with dark red, while the margins of the uropods of the tail are green along their margins (Williams 1984). Its carapace has a medial carina (keel-like ridge) that is continuous with the rostrum at the anterior end of the animal, and extends posteriorly approximately 2/3 the length of the carapace. The rostrum is elongate and slender, somewhat distally upcurved, with 5 - 11 (usually 9) sharp teeth on the dorsal surface, and 2 teeth on the ventral edge. Unlike its congeners P. aztecus and P. duorarum, P. setiferus has no bordering groove along the carina. The integument is thin, and appears polished and translucent.The abdomen is carinate on segments 4 - 6, with the carina of segment 6 having a narrow groove on either side. The telson has a deep medial groove along its length, and a sharp tip. The ventral margin of the pleura of the first segment is almost straight.P. setiferus is sexually dimorphic, with females growing larger than males. Additionally, the female thelycum, which lies between pereopods 3- 5, is open and has raised ridges along the anterolateral surface. The male pentasma has a diagonal ridge across the dorsolateral lobe.

The distribution of the White shrimp (Litopenaeus setiferus) appears to be discontinuous. It occurs along the Atlantic Coast of the United States from Fire Island (New York) south to central Florida and along the north coast of the Gulf of Mexico and the northeastern coast of Mexico (with a center of abundance in Louisiana), continuing southward to Campeche, Mexico (with another center of abundance in northeast Tabasco and the adjacent waters of Campeche). In addition to the large distributional discontinuity around southern Florida and the west side of the Florida Peninsula, this species is patchily distributed within its range on a smaller scale, possibly as a result of local variation in salinity, temperature, substrate, food, or cover. (Perez-Farfante 1969)

Fire Island, N.Y., to Saint Lucie Inlet, Fla; Gulf of Mexico from Ochlocknee River, Fla., to Campeche, Mexico

Gulf of Mexico, North West Atlantic

White shrimp are known from Fire Island, New York south to St. Lucie Inlet, Florida. The range then extends around the Florida Peninsula into the Gulf of Mexico from the Ochlocknee River in northwest Florida to Campeche, Mexico. Several centers of abundance have been identified for P. setiferus. Primary among them is coastal Louisiana around the Mississippi River Delta. Other abundance areas occur in northeast Florida, Georgia, and the region around the Bay of Campeche, Mexico (Williams 1984). White shrimp are distributed throughout the Indian River Lagoon and along the east central Florida coast where they are commonly utilized as bait and for food.

Large males measure approximately 182 mm in length. Large females grow slightly larger and eventually reach 200 mm. Williams (1984) reported that females beyond the juvenile stage are consistently larger than males.In estuaries, juvenile white shrimp grow approximately 1.2 mm per day during late spring and summer months (Williams 1965). Growth is slow in spring, but quickens with the onset of summer. Growth rates decrease during the fall months, but shrimp that remain in estuaries to overwinter resume growing the following spring (Muncy 1984). Few white shrimp live as long as a year (Anderson 1966), however, mark-recapture studies have revealed that some white shrimp live from 27 months to as much as 4 years (Etzold and Christmas 1977; Klima et al. 1982).

Depth range based on 1020 specimens in 1 taxon.
Water temperature and chemistry ranges based on 237 samples.

Environmental ranges
  Depth range (m): 0 - 119
  Temperature range (°C): 8.794 - 25.874
  Nitrate (umol/L): 0.289 - 24.158
  Salinity (PPS): 33.890 - 36.185
  Oxygen (ml/l): 2.750 - 5.180
  Phosphate (umol/l): 0.092 - 2.064
  Silicate (umol/l): 0.756 - 29.974

Graphical representation

Depth range (m): 0 - 119

Temperature range (°C): 8.794 - 25.874

Nitrate (umol/L): 0.289 - 24.158

Salinity (PPS): 33.890 - 36.185

Oxygen (ml/l): 2.750 - 5.180

Phosphate (umol/l): 0.092 - 2.064

Silicate (umol/l): 0.756 - 29.974
 
Note: this information has not been validated. Check this *note*. Your feedback is most welcome.

Depth range based on 1 specimen in 1 taxon.

Environmental ranges
  Depth range (m): 15 - 15
 
Note: this information has not been validated. Check this *note*. Your feedback is most welcome.

White Shrimp are found primarily at depths less than about 36 meters, although they may occur to 80 meters (Perez-Farfante 1969 and references therein).

White Shrimp inshore live mostly on muddy or peaty bottoms that have large quantities of decaying organic matter or vegetation for protection. Occasionally they occur on bottoms of sand or clay. Adult White Shrimp are most abundant in offshore waters on soft muddy and silt bottoms. They also live on bottoms of clay or sand with fragments of shells. They burrow in the bottom, but apparently not as regularly as do the Brown (Farfantepenaeus aztecus) or Pink (F. duorarum) Shrimps. The White Shrimp leaves its long antennae lying on the surface of the bottom, whereas the other two shrimps often bury their antennae (which are shorter than those of the white shrimp). (Perez-Farfante 1969 and references therein.)

White Shrimp juveniles require an estuarine environment for development. The adults live and spawn offshore, and their favored habitats include areas with abundant plant life and muddy substrates. (McMillen-Jackson and Bert 2003 and references therein).

White shrimp larvae feed on both zooplankton such as copepods, and phytoplankton such as unicellular green algae, and diatoms. Juvenile and adult white shrimp are benthic omnivores that feed on detritus, plants, microorganisms, macroinvertebrates (annelids, copepods, amphipods, snails, bryozoans, etc.) and small fish (Muncy 1984). Cannibalism is also common among adult white shrimp (Perez-Farfante 1969).Competitors: Penaeus setiferus is likely to compete with its congeners P. aztecus and P. duorarum for resources as well as for habitat. However, white shrimp are known to burrow more shallowly into muddy substrata, and have been shown to be somewhat more active during daylight hours than either brown or pink shrimp. Seasonal recruitment of the 3 common Penaeus species into estuarine nursery grounds is also somewhat staggered, thus reducing direct competition for resources.Habitats: Penaeus setiferus commonly inhabits estuaries and the inner littoral zone along coasts to depths of approximately 30 m. In the Gulf of Mexico, P. setiferus can be found in depths as great as 80 m; however, they are most abundant in brackish wetlands with connections to shallow, coastal areas.Juvenile Penaeus setiferus prefer muddy substrata rich in loose peat and sandy mud (Williams 1958). Anderson (1966) reported that ideal nursery grounds for juvenile white shrimp are muddy bottom areas in waters with low to moderate salinity.Activity Time: Juvenile white shrimp are generally more active in daylight hours than juveniles of either pink or brown shrimp (Muncy 1984).

White shrimp are omnivorous. Their digestive tracts have been found to contain, in addition to inorganic detritus and organic debris, fragments of many different animals, particles of higher plants, and a variety of diatoms and other algae (Perez-Farfante 1969 and references therein).

White shrimp are often found in association with other shrimp species, specifically the brown shrimp P. aztecus. Habitat requirements between these 2 species are similar, and brown shrimp have been observed to force white shrimp from sandy, muddy substrata (Rulifson 1981). However, staggered recruitment periods between these species decreases direct competition for resources.

White Shrimp are fed on by a wide variety of fish species and are parasitized by a range of organisms, including trematode and cestode flatworms, nematodes, and others (Perez-Farfante 1969 and references therein).

Penaeus setiferus is a commercially valuable fishery species and can be highly abundant throughout its range. Major abundance centers are located from Georgia to Florida, Louisiana, and the Bay of Campeche, Mexico.Locomotion: Penaeus setiferus actively swims, burrows shallowly, and crawls.

White Shrimp eggs hatch within a few hours after spawning and the young emerge as nauplii, the first of 11 larval stages (Perez-Farfante 1969 and references therein).

Mature males produce ripe sperm when they reach lengths of approximately 118 mm. Females mature at lengths of approximately 135 - 140 mm. Gonadal development in females can be judged by ovary color. Undeveloped ovaries are opaque and white in color. Developing ovaries appear yellow, a stage which may last 1 - 2 months. Ripe ovaries are an olive color, and may remain so until fully spent (generally in less than 1 month). Spent ovaries quickly develop to the yellow stage within a few days, and will ripen again within 2 - 3 months (King 1948; Brown and Patlan 1974).Spawning behavior in P. setiferus is initiated by an increase in offshore bottom water temperatures during spring (Whitaker 1981). In the Carolinas, spawning occurs from May through September (Williams 1955), while further south in the Gulf of Mexico, spawning occurs from March through September. Williams (1965) and Joyce (1965) each reported only one spawning period for P. setiferus. However, Gunter (1950) suggested spring and fall spawning periods in Texas waters.Spawning occurs as far as 9 km from the shore, in water depths of at least 9 m (Whitaker 1983b), with females discharging eggs directly to the water column without brooding them as is common in other crustaceans. During copulation, which occurs between hard-shelled individuals, the male attaches a spermatophore to the thelycum of a female. Spermatozoa are released simultaneously with eggs from the female, with fertilization occurring in the water column. Eggs are opaque with a blue-tinged chorion (Linder and Cook 1970) and measure approximately 0.19 - 0.20 mm in diameter. Eggs sink to the bottom of the water column as they are released, and hatch within 10 - 12 hours into planktonic nauplii larvae that measure approximately 0.3 mm in length. Between 500,000 to 1 million eggs are released per spawn.

Reproduction in the White Shrimp and close relatives is facilitated by the transfer of a spermatophore from the male to a modified region of the sternum of the female (the thelycum). The spermatophore consists of a roughly semicylindrical hardened sperm sac enclosing a columnar sperm mass (spermatozoa within a viscous fluid) surrounded by a thick "sheath" of gelatinous substance (Perez Farfante 1975 and references therein). Misamore and Browdy (1996) studied the mating behavior of the White Shrimp. They recognized 4 sequential stages. During the Chase stage, the male closely trails the female, mirroring the female's changes in direction. In the Probe stage, the male approaches the female ventrally and probes the thelycal region of the female with its antennules. The Embrace stage is characterized by the male inverting itself, juxtaposing ventral surfaces with the female, and wrapping its pereiopods around the carapace of the female. In the final stage, the Flex, the male collapses its uropods, hooks its abdomen slightly, and rotates perpendicular to the midline of the female forming a U-shape around the female.

The larval period in P. setiferus lasts 10 days or more. Perez-Farfante (1969) reported 5 naupliar stages, 3 protozoeal stages, 3 mysis stages, and 2 postlarval stages before the juvenile stage is reached. The non-feeding nauplius stage undergoes 5 molts over 24 - 36 hours to the protozoeal stage which measures approximately 1 mm in length. Feeding behavior is initiated with the first protozoeal stage. Protozoea grow to a length of approximately 2.5 mm before achieving the mysis stage. Following a third mysis stage, the postlarval stage is attained.Postlarvae of P. setiferus are planktonic, gradually moving inshore to estuarine nursery grounds on tidal currents (Whitaker 1983a). Most enter estuaries as second stage postlarvae measuring approximately 7 mm in length. Upon reaching estuaries postlarvae become benthic (Williams 1965). In North and South Carolina, postlarval P. setiferus enter estuaries from June through September; in Georgia, postlarvae may enter estuaries as early as April and May. In northeastern Florida, postlarvae first begin to appear in early June.Perez-Farfante (1969) considered postlarvae to be juveniles once they had acquired 4 - 10 upper rostral teeth, and 1 to 3 lower rostral teeth.

Perez-Farfante and Kensley (1997, cited in Maggioni et al. 2001) proposed that the four Penaeus subgenera of Perez-Farfante (1969) be raised to generic status, changing the name of the White Shrimp from Penaeus setiferus to Litopenaeus setiferus. Although Baldwin et al. (1998) questioned this approach based on their molecular data, additional molecular studies by Maggioni et al. (2001) largely supported the recommendations of Perez-Farfante et al. (1997).

For decades, White Shrimp and the closely related Brown (Farfantepenaeus aztecus) and pink (F. duorarum) shrimp were thought to be impervious to overfishing due to their high fecundity and annual life cycle. However, recent reports of growth overfishing (i.e., shrimp being caught before reaching a size at which maximum growth and productivity would be obtained from the population) have raised concerns about the health of the populations (Ball and Chapman 2003 and references therein),

The White Shrimp (Litopenaeus setiferus) is an abundant species and important to both commercial and recreational fisheries throughout its range (Ball and Chapman 2003).

Three species of penaeid shrimp (White, Pink, and Brown shrimp) comprise more than 99% of the landings in the Gulf of Mexico shrimp fishery. In recent years, average annual landings of the three species have been approximately 150 million pounds; however, since 2002 landings have declined sharply due to economic conditions in the fishery and hurricane damage, particularly in 2005 when landings dropped to approximately 92 million pounds. (NOAA/NMFS http://www.nmfs.noaa.gov/fishwatch/species/wild_white_shrimp.htm, page updated 1 February 2010)

The White Shrimp was the only shrimp fished in the estuarine waters along the northern coast of the Gulf of Mexico until about 1937-38, when offshore stocks began to be fished. The resource then declined while landings of Brown and Pink Shrimps increased. By the mid-1950, catches of those two species far exceeded catches of White Shrimp. During 1956-59, White Shrimp constituted only 20% of all Gulf shrimp produced by U.S. fishermen, but subsequently landings began to rise again. Annual landings of White Shrimp in the United States during 1965 were nearly 68 million pounds (whole weight), or about 31 percent of all shrimp landed. (Perez-Farfante 1969 and references therein)

Today, White Shrimp are the second most abundant species (after Brown Shrimp), with 1998 and 1999 landings of approximately 55 million pounds and 2000 landings of over 70 million pounds. From 2000 to 2005, landings fluctuated from a low around 80 million pounds to a high of 130 million pounds. Fluctuation in landings is partly the result of the level of effort in the fishery, which in turn is influenced by expected market prices. A total of about 110 million pounds of White Shrimp were landed in U.S. fisheries in 2008, mainly off of Texas and Louisiana. (NOAA/NMFS http://www.nmfs.noaa.gov/fishwatch/species/wild_white_shrimp.htm, page updated 1 February 2010)

Fisheries.Benefit in IRL: National Marine Fisheries Service data reported the statewide commercial catch for white shrimp in Florida between 1987 - 2001 to be 52.3 million pounds with a dollar value of $139.2 million. BIBLIOGRAPHYAldrich, D.V., C.E. Wood, and K.N. Baxter. 1968. An ecological interpretation of low temperature responses in Penaeus aztecus and P. setiferus postlarvae. Bull. Mar. Sci. 18(1):61-71.Anderson, W.W. 1966. The shrimp and the shrimp fishery of the southern United States. U.S. Fish and Wildl. Serv. Bur. Commer. Fish. Fish. Leafl. 589. 8 pp.Brown, A., Jr. and D. Patlan. 1974. Color changes in the ovaries of penaeid shrimp as a determinant of their maturity. Mar. Fish. Rev., 36(7):23-26, colored figures 1-12.Etzold, D.J. and J.Y. Christmas. 1977. A comprehensive summary of the shrimp fishery of the Gulf of Mexico United States: a regional management plan. Gulf Coast Res. Lab. Tech. Rept. Ser. No. 2, part 2. 20 pps.Gunter, G. 1950. Seasonal population changes and distributions as related to salinity, of certain invertebrates if the Texas coast, including the commercial shrimp. Publications of the Inst. of Mar. Sci., Texas, 1(2):7-51.Joyce, E.A. 1965. The commercial shrimps of the northeast coast of Florida. Fl. Board Conserv. Mar. Lab. Prof. Pap. Ser. 6. 224 pp.King, J.E. 1948. A study of the reproductive organs of the common marine shrimp, Penaeus setiferus (Linnaeus). Biol. Bull. 94(3):244-262Klima, E.F., K.N. Baxter, and F.J. Patella, Jr. 1982. A review of the offshore shrimp fishery and the 1981 Texas closure. Mar., Fish. Rev. 44:16-30.Linder, M.J. and H.L. Cook. 1970. Synopsis of biological data on the white shrimp Penaeus setiferus (Linnaeus) 1767. FAO Fisheries Synopsis 101. FAO Fish. Rep. 4:1439-1469.Muncy, R.J. 1984. Species profiles: life histories and environmental requirements of coastal fishes and invertebrates (south Atlantic): white shrimp. U.S. Fish and Wildl. Serv. FWS/OBS-82/11.27. U.S. Army Corps of Engineers, TREL-82-4. 19 pp.Perez-Farfante, I. 1969. Western Atlantic shrimps of the genus Penaeus. U.S. Fish Wildl. Serv. Fish. Bull. 67(3):461-591.Rulifson, R.A. 1981. Substrate preference of juvenile penaeid shrimp in estuarine habitats. Contrib. Mar. Sci. 24:35-52.Whitaker, J.D. 1981. Biology of the species and habitat descriptions. In M.D. McKenzie, ed. Profile of the penaeid shrimp fishery in the south Atlantic. South Atlantic Manag. Council, Charleston, SC.Whitaker, J.D. 1983a. Effects of severe winters on white shrimp stocks in the Atlantic Ocean off the southeastern United States. Presented at Natl. Shellfish Assoc. Hiltonhead, SC. June 1983. 6 pp.Whitaker, J.D. 1983b. Roe shrimp tagging 1983. Proj. Rep. S.C. Wildl. Mar. Res. Dep., Charleston, SC. 4 pp.Williams, A.B. 1955. A contribution to the life histories of commercial shrimps (Penaeidae) in North Carolina. Bulletin of Marine Science of the Gulf and Caribbean 5(2):116-146.Williams, A.B. 1958. Substrates as a factor in shrimp distribution. Limnol. and Oceanogr. 3(3):283-290.Williams, A.B. 1965. Marine decapod crustaceans of the Carolinas. Fish. Bull., 65(1):I-xi + 298 pages.Williams, A.B. 1984. Shrimps, lobsters and crabs of the Atlantic coast of the eastern United States, Maine to Florida. Smithsonian Institution Press. Washington, D.C. 550 pp.Zein-Eldin, Z.P. 1964. Growth and metabolism. U.S. Bur. Commer. Fish. Circ. 183:65-67.