(DRAFT) - Taxonomy
Species shrimp, white
Species Id M070005
Date 26 AUG 96

TAXONOMY

NAME - shrimp, white

OTHER COMMON NAMES - gray shrimp, lake shrimp, green shrimp, green-tailed shrimp, blue-tailed shrimp, rainbow shrimp, Daytona shrimp, common shrimp, southern shrimp and camaron blanco

ELEMENT CODE -

CATEGORY - Aquatic Crustaceans

PHYLUM AND SUBPHYLUM - , Crustacea

CLASS AND SUBCLASS - Malacostraca, Eumalacostraca

ORDER AND SUBORDER - Decapoda, Dendrobranchiata

FAMILY AND SUBFAMILY - Penaeidae,

GENUS AND SUBGENUS - Penaeus,

SPECIES AND SSP - setiferus,

SCIENTIFIC NAME - Penaeus setiferus

AUTHORITY - Linnaeus, 1767

TAXONOMY REFERENCES - 197, 61

COMMENTS ON TAXONOMY -
Other names.....Gray shrimp, lake shrimp, green shrimp, green-tailed shrimp,
blue-tailed shrimp, rainbow shrimp, Daytona shrimp, common shrimp, southern
shrimp; in Mexico: camaron blanco (Perez Farfante 1969).*61*

Taxonomy - 1 (DRAFT) - Status
Species shrimp, white
Species Id M070005
Date 26 AUG 96

STATUS

Coded Status
Game (Consumptive Recreational)
Commercial
Commercial/consumption
Commercial/bait

REFERENCES FOR STATUS - 61

COMMENTS ON STATUS -
The white shrimp was the first American shrimp to be extensively marketed
for food. Commercial shrimping in the United States began as early as 1709;
catches reached 8,181 metric tons (t) in 1917 (when trawls replaced haul
seines), and peaked in the late 1920's. By the 1930's, there was concern
that the intensive fishery along the southeastern Atlantic coast (North
Carolina, South Carolina, Georgia, and northeast Florida) was depleting the
resource. White shrimp contributed an estimated 95% of shrimp catches in
1931. The annual white shrimp landings for 1976-80 averaged 3,480 t. The
decrease was attributed to recent severe winters and cold waters during
that period. The harvest of 2,685 t of white shrimp from the Southeastern
States in 1982 was valued at $29.4 million.*61*

In 1957-80, the mean yearly catch of 3,991 t of white shrimp contributed 58%
of the total catch of penaeid shrimp in the United States. Shrimp accounted
for 82% of the ex-vessel 1971-77 values of marine products landed in
Georgia.*61*

Catches by sport shrimpers are rarely estimated but they must be
considerable. Despite difficulties in estimating recreational shrimp
fishing, McKenzie reported that in 1973, 43% of coastal boat owners in South
Carolina fished for shrimp with non-licensed gear and in 1978, 46% of shrimp
craft owners in North Carolina reported "sport shrimping". The white shrimp
is an important food of many marine and estuarine fishes and invertebrates
and is heavily used for bait in South Carolina, Georgia, and Florida. In
Georgia, 1,479 noncommercial recreational bait shrimpers were licensed in
1982-83. In 1980, the estimated commercial wholesale bait shrimp catch in
northeast Florida was 19.6 million live shrimp valued at $0.77 million and
413.6 t of dead shrimp valued at $1.32 million.*61*

Status - 1 (DRAFT) - Distribution
Species shrimp, white
Species Id M070005
Date 26 AUG 96

DISTRIBUTION

Distribution - 1 HABITAT ASSOCIATIONS

HABITAT - AQUATIC

REFERENCES FOR HABITAT - 61

NATIONAL WETLAND INVENTORY CODES

NWI NWICLS NWIMOD NWISPEC

Marine UB3
Marine UB3
Marine EM. S
Marine OW0 N
Marine UB. N
Estuarine, subtidal EM. N
Estuarine EM. L
Estuarine UB3
Marine OW0 R
Marine UB.
Marine UB4

REFERENCES FOR NWI - 61

Habitat Associations - 1 (DRAFT) - Food Habits
Species shrimp, white
Species Id M070005
Date 26 AUG 96

FOOD HABITS

TROPHIC LEVEL -
OMNIVORE

REFERENCES FOR TROPHIC LEVEL - 61

LIFESTAGE FOOD FOOD PART
Larva Phytoplankton Not Applicable
Larva Zooplankton Not Applicable
Larva Microorganisms Not Specified
General Detritus Not Applicable
General Feces Not Applicable
General Microorganisms Not Applicable

REFERENCES FOR GENERAL FOOD - 61

COMMENTS ON FOOD -
White shrimp convert detritus, plant material, microorganisms,
macroinvertebrates, and fish parts into useful protein for carnivores.
Juvenile and adult white shrimp are benthic omnivores; the major differences
in food selection are the kinds and availability of materials selected.
Juvenile and adult penaeids are benthic omnivores that feed largely at
night, except in turbid waters. Fecal pellets of fish and invertebrates can
be an important food item of juvenile shrimp. Lindner and Cook (1970) noted
that white shrimp were selective particulate feeders. Major food reported
in three studes were detritus, chitin, parts of annelids and gastropods,
fish parts, bryozoans, sponges, corals, filaments of algae, and vascular
plant stems and roots. Lipids supplied by annelids in the diet were
important for ovarian maturation.*61*

COMMENTS ON LARVAE FOOD -
Nauplii subsist on yolk granules until they reach the protozoea I stage.
White shrimp larvae feed on zooplankton and phytoplankton; white shrimp
protozoea feed on green algae, diatoms, or copepods. In a laboratory test,
cultured algae were fed to protozoea and newly hatched brine shrimp up to
the mysis stage. Early stages of white shrimp larvae feed on plankton and
suspended detritus.*61*

Food Habits - 1 (DRAFT) - Environment Associations
Species shrimp, white
Species Id M070005
Date 26 AUG 96

ENVIRONMENTAL ASSOCIATIONS

G = General A = Adult
LIM = Limiting RA = Resting Adult
J = Juvenile FA = Feeding Adult
RJ = Resting Juvenile BA = Breeding Adult
FJ = Feeding Juvenile P = Pupae
L = Larvae E = Egg
RL = Resting Larvae
FL = Feeding Larvae

LIFESTAGE ENVIRONMENTAL ASSOCIATIONS
G Water Temperature: Specified in Comments
G
G Nutrient [Phosphorus and Nitrogen]: High nutrient concentrations [eutrophic
G Bottom Type [Aquatic]: Mud or silt
G Bottom Type [Aquatic]: Organic debris
G Bottom Type [Aquatic]: Rooted aquatic vegetation
G Density of Aquatic Vegetation: High

REFERENCES FOR ENVIRONMENTAL ASSOC_ - 61

COMMENTS ON ENVIRONMENTAL ASSOCIATIONS -
Water temperature directly or indirectly influences white shrimp spawning,
growth, habitat selection, osmoregulation movement, mirgration, and
mortality. Spring water temperature increases trigger spawning, and rapid
water temperature declines in fall portend the end of spawning. Growth is
fastest in summer and slow or negligible in winter. Water temperatures
below 20 degrees C inhibit growth of juvenile shrimp and growth is
virtually nil at 16 degrees C. Growth rates increase rapidly as
temperatures increase above 20 degrees C. Increased water temperature
affects molting rate. Good correlatation between heating-degree-days and
catch/effort ratio for penaeid shrimp was similar to correlations and
yield-per-hectare versus latitude. Temperature and food supply limited the
growth of white shrimp postlarvae more than did salinity differences
between 2 and 35 ppt.*61*

White shrimp are more tolerant of high temperatures and less tolerant of
low temperatures than either brown or pink shrimp. Among postlarvae, brown
shrimp were more resistant than white shrimp to higher temperatures.*61*

White shrimp mortality was reported at water temperatures of 8 degrees C
and lower. Mortality of white shrimp is total at 3 degrees C or lower,
regardless of salinity. White shrimp survival at low temperatures depends
on ambient temperature, the rate of temperature decline, the duration of
low temperatures and salinity. The impact of low water temperature and low
salinity on white shrimp was discussed by Music (1979) and Shipman. Adult
white shrimp (>90 mm long) may be more susceptible than juveniles to cold
temperatures. Wiesepape (1975) found the 24-h LC(subscript-50) temperature
causing 50% mortality in 24 h) to be 36 degrees and 37 degrees C for white
shrimp acclimated at 29 degrees and 34 degrees C, respectively.
Environment Associations - 1 (DRAFT) - Environment Associations
Species shrimp, white
Species Id M070005
Date 26 AUG 96

Postlarvae and 30-mm long juveniles have similar but higher resistance
times than 50-mm juveniles.*61*

Salinity. Adult white shrimp spawn offshore where salinities are at least
27 ppt. The larvae move shoreward and become second-stage portlarvae as
they enter estuaries on flood tides. Juvenile white shrimp moved 160 km
upstream into water of less than 1.0-ppt salinity waters in the St. Johns
River, Florida. Juvenile white shrimp have even been recovered from Lake
Monroe Power Station filter screens located 270 km from the mouth of the
St. Johns River -- especially when low rainfall and low river stages caused
reverse tidal flow. The high calcium ion concentrations in the St. Johns
River may explain the relative ease with which marine species enter and
remain in low salinity waters. The lowest salinity in which white shrimp
were recorded in the northern Gulf of Mexico was 0.42 ppt. Although field
studies indicate that juvenile white shrimp prefer low salinities,
laboratory studies have revealed that white shrimp appear to tolerate a
wide range of salinities; they have been successfully reared at salinities
of 18 to 34 ppt. McKenzie (1981) cited several studies in which fast
growth was reported for white shrimp at salinities of 7 to 15 ppt.*61*

Temperature-Salinity Interactions. Temperature-salinity tolerance ranges
for white shrimp vary at different life stages, but the interactions are
more pronounced at the extremes of tolerance. For example, Couch (1978)
reported that broken-back syndrome (dorsal separation of third and fourth
pleural plates on abdominal) appears after sudden drops in salinity (from
15 ppt to 3 ppt) in cold water (8 degrees C). The critical thermal maxima
for white shrimp are influenced largely by acclimation temperatures, and to
a lesser extent by salinity and size of test animal. Freshwater inflow may
affect coastal water temperatures, which in turn affect the growth rates
and migration of white shrimp. Spring spawning of white shrimp coincides
with a rapid rise in bottom water temperatures in high salinity offshore
waters.*61*

Substrate. The relation between inshore catches and hectares of vegetated
estuarine habitat in the northeastern Gulf of Mexico also showed a strong
correlation (R squared = 0.64). A direct relationship between commercial
shrimp landings and intertidal vegetated areas and degrees latitude was
reported by Turner (1977).*61*

Environment Associations - 2 (DRAFT) - Life History
Species shrimp, white
Species Id M070005
Date 26 AUG 96

LIFE HISTORY

PHYSICAL DESCRIPTION:

Freshly caught white shrimp often have widely spaced body chromatophores;
consequently they are lighter colored than pink or brown shrimp. The white
shrimp is sometimes called the non-grooved shrimp (Whitacker 1981) because
its adrostral carina does not extend behind the middle of carapace in adults
nor to the posterior margin of carapace in juveniles. In contrast, the
brown shrimp (P. aztecus) and pink shrimp (P. duorarum), co-existing along
the southeast and gulf coasts of the United States, each has a deep groove
(adrostral sulcus) extending almost to the posterior margin of the carapace.
In the white shrimp, the adrostral sulcus is short, extending to the
epigastric back tooth of the rostrum. Gastrofrontal carina is absent.
Thelycum is open, with anterolateral ridges; mesially turned pair of fleshy
protuberances on sternite XIV. Antennal flagella 2.5 to 3 times the body
length in Penaeus setiferus as in P. schmitt, a species found in Cuba, the
Virgin Islands, and along eastern Central and South American Atlantic coast
south to Laguna, Brazil. Zamora and Trent (1986) noted that the keel was
smooth on the sixth abdominal somite of postlarvae white shrimp but bore
spines on brown shrimp and pink shrimp.*61*

Sexes are easily distinguishable by the modified endopod of the first pair
of pleopods on the males and the open-type thelycum between third, fourth,
and fifth pereopods on the females. At lengths of 28 mm, males can be
distinguished from females by the shorter and narrower endopods of the first
pleopods and by two protuberances on sternite XIV.*61*

REPRODUCTION:

Along the south Atlantic coast of the United States, white shrimp spawn from
March to November, but mostly from April (May in South Carolina) to October.
According to McKenzie (1981) spawning conditions extended into September in
South Carolina, Georgia, and northeast Florida, and into October in central
Florida. Shrimp spawn as late as November in Georgia, activity decreasing
from south to north. Spawning peaks in May and June along the offshore
water of northeast Florida. In general, the increase of bottom water
temperatures in spring triggers spawning, and rapid decreases in water
temperature in the fall coincide with the end of spawning. As judged by
the low percentages of spent females in June to August, white shrimp may
spawn as many as four times during their life span; however, there is some
evidence that they spawn only once in Carolina waters.*61*

White shrimp spawn along the South Atlantic coast of the United States in
water more than 9 m deep, and within 9 km from the shore. Spawning shrimp
seemingly prefer salinities of 27 ppt or more. In the Gulf of Mexico most
white shrimp spawn at depths of 8 to 31 m. Sexually mature and spent female
white shrimp were captured along the northeast Florida coast only in
offshore water depths over 11 m. Little is known about the spawning
location offshore from North and South Carolina, but adult shrimp tagged in
North Edisto River estuary in South Carolina in May 1983 were recaptured
within 9 km from the coast.*61*

Life History - 1 (DRAFT) - Life History
Species shrimp, white
Species Id M070005
Date 26 AUG 96

White shrimp were first spawned in captivity in 1980. The general
requirements for maturation and reproduction usually fall in the range of
20% to 60% light intensity, 10 to 14 h photoperiod, 20 degrees to 28 degrees
C water temperature, and 26 to 34 ppt salinities. In some laboratory
experiments, white shrimp spawned only at night but in others some spawned
during daylight. The food source required was fresh marine invertebrates
and fish supplied at 3% to 5% dry weight of the weight of the shrimp.*61*

In copulation (limited to hard-shelled individuals), the male attaches a
spermatophore onto the thelycum of the female. Spermatozoa are believed to
be released from the spermatophore simultaneously with expulsion of the ova.
About 0.5 to 1 million eggs are discharged per spawn from each female.*61*

The eggs of white shrimp are discharged directly into the water and sink to
the bottom. The spherical and opaque ripe eggs, which are 0.192 to 0.3 mm
in diameter, have a purplish-blue chorion.*61*

BEHAVIOR:

Migration. White shrimp along the southeast Atlantic coast migrate
southward during autumn and early winter and then northward in late winter
and early spring. More specific migrations reported by Joyce (1965) showed
a major southerly migration from North Carolina to Cape Canaveral, Florida,
in fall and a northerly migration from the Cape in spring. In Georgia, a
mark and recapture study revealed that 96% of the shrimp recovered in the
winter came from more southerly waters. A white shrimp tagged in October
off North Carolina was recaptured 576 km southward off Florida's east coast
and one white shrimp tagged January off central Florida was recaptured 416
km to the north off South Carolina. Whitaker suggested a correlation
between shrimp migration and latitude with activity being greatest in the
more southern areas. In northeast Florida, white shrimp 120 to 140 mm TL
moved offshore from August through April. Detailed analysis of white shrimp
sampling from June 1962 - June 1963 by Joyce (1965) revealed that white
shrimp caught off Cape Canaveral, Florida had migrated from more northern
nursery areas in December and January, suggesting that Cape Canaveral is the
southern limit of commercial white shrimping along Florida's east coast.
Southward movements of 10 to 20 km per day during fall were suggested
by Joyce for schooling white shrimp along the northeast Florida coast.
Movements of individual shrimp tagged in Georgia waters and recaptured off
Florida ranged from 1.8 to 6.9 nautical miles per day. Offshore migrants
make up the valuable spring fishery for adult famales in Georgia, South
Carolina, and North Carolina in years following relatively mild winters.*61*

White shrimp emigration from estuaries is governed largely by body size,
age, and environmental conditions. Low water temperatures (<18 degrees C)
and spring tides at full moon stimulated mass movements from South Carolina
estuaries. During ebb tides, white shrimp tend to school and migrate near
the surface at night. Williams (1958) suggested that muddy substrate is not
strongly preferred during emigration from estuaries to the sea. Emigration
was delayed in South Carolina and Georgia when unusually low freshwater
inflow caused high salinities. In South Caolina, shrimp congregated in the
deeper channels (staging areas) as water temperatures declined to about 9
degrees C. Recent studies showed that white shrimp movements offshore in
Life History - 2 (DRAFT) - Life History
Species shrimp, white
Species Id M070005
Date 26 AUG 96

fall and winter are triggered by water temperature declines in estuaries in
the south Atlantic, and Louisiana. Precipitation, spring tides, and strong
tidal exchanges associated with northeasterly storms also influence the
timing and magnitude of emigraton from inshore waters.*61*

LIMITING FACTORS:

Diseases and parasites. The effect of diseases and parasites on white
shrimp mortality is not well known. A 99% loss of egg production was
attributed to a microsporidian parasite infection of white shrimp gonads,
yet the next year's production was as high as that of the preceeding year.
Vibrio infection of male white shrimp prevented egg fertilization under
laboratory conditions. Literature reviews of diseases and parasites of
penaeid shrimp show that viruses, bacteria, fungi, protozoa, helminths, and
nematodes often infect shrimp. Diseases and parasites ranked after
predation and periodic physical catastrophes as limiting factors in nature
and after nutrition and reproduction requirements in mariculture.
Symbionts may be related to shrimp kills during low oxygen conditions. A
parasitic cestode, Prochritanella penaei, infecting the hepattopancreas of
adult shrimp is of some concern in the Mississippi Sound; however, from an
economic standpoint, microsporidian protozoans that cause a "cotton"
appearance in the musculature of shrimp are the most threatening. In
Georgia in 1978-81, microsporidian parasites were observed in 3.9% of 33,350
white shrimp captured for tagging. Lower recovery rates of tags from
infected than from uninfected shrimp suggested higher mortality among the
infected shrimp. Hutton et al. (1959) suggested that infected shrimp may be
more susceptible to predation and disease.*61*

Environment. The loss of nursery grounds has been considered the major
threat to the white shrimp fishery in the Gulf of Mexico because that is
where shrimp are most vulnerable to habitat disturbance. Studies in
Florida, Louisiana, and Texas identified landfill, dredging, and
impoundments as major detriments to shrimp production. Because of the loss
of rich organic material along bulkheads, shrimp abundance there was
reduced to about 1/8 that of nearby unaltered shorelines. About 18,171 ha
of wetlands, 3.5% of the total, were lost from the Sourth Atlantic coast
between 1954 and 1968. Manmade canals in Louisiana estuaries have increased
salinity and adversely affected white shrimp survival and growth. Trawl
catches of white shrimp dropped below seasonal averages when dissolved
oxygen was below 3.0 mg/l in altered, eutrophic canals associated with
housing developments in West Bay, Texas.*61*

Temperature. Water temperatures below 20 degrees C inhibit growth of
juvenile shrimp and growth is virtually nil at 16 degrees C. White shrimp
are more tolerant of high temperatures and less tolerant of low temperatures
than either brown or pink shrimp. Among postlarvae, brown shrimp were more
resistant than white shrimp to higher temperatures.

susceptible than juveniles to cold temperatures. It was found that the 24-h
LC (subscript 50) (temperature causing 50% mortality in 24 h) to be 36
degrees and 37 degrees C for white shrimp acclimated at 29 degrees and 34
degrees C, respectively. Postlarvae and 30-mm long juveniles have similar
but higher resistance times than 50-mm juveniles.*61*

Salinity. The lowest salinity in which white shrimp were recorded in the
northern Gulf of Mexico was 0.42 ppt. Although field studes indicate that
juvenile white shrimp prefer low salinities, laboratory studies have
revealed that white shrimp appear to tolerate a wide range of salinities;
they have been successfully reared at salinities of 18 to 34 ppt.*61*

Other Environmental Considerations. The loss of nursery grounds has been
considered the major threat to the white shrimp fishery in the Gulf of
Mexico because that is where shrimp are most vulnerable to habitat
disturbance. Studies in Florida, Louisiana, and Texas indentified landfill,
dredging, and impoundments as major detriments to shrimp production. Manmade
canals in Louisiana estuaries have increased salinity and adversely affected
white shrimp survival and growth. Increased salinities have favored brown
shrimp over white shrimp in the central-northern Gulf of Mexico. Trawl
catches of white shrimp dropped below seasonal averages when dissolved
oxygen was below 3.0 mg/l in altered, eutrophic canals associated with
housing developments in West Bay, Texas.*61*

POPULATION ATTRIBUTES:

Growth. Juvenile white shrimp grow during summer and fall, grow slowly over
winter, and then resume growth as water temperatures rise in the estuaries
during April and May. Spring growth is about equal to the summer growth of
18 to 30 mm per month. Similar growth rates were calculated from
mark-recapture studies in Georgia from 1978 to 1981. The rate of increase
in weight is relatively low among the small white shrimp, highest in
mid-sizes, and decreasing among the larger ones.

Following two mysis stages and two postlarval stages, young white shrimp 7
mm long enter the estuaries where their growth rate is about 1.2 mm per day.
Juvenile shrimp in the south Atlantic grow 1.0 to 2.3 mm per day or 28 to 64
mm per month.

Female shrimp grow faster and reach larger sizes than males. In northeast
Florida the largest female sampled was 192 mm long and the largest male was
175 mm long; most shrimp longer than 115 mm were females.*61*

Mortality. Few white shrimp live as long as one year; however, mark and
recapture studies showed that a few lived as long as 27 months in
Mississippi, more than 17 months in Georgia, and as long as 4 years (average
18 months) in Texas. Because of the usually short life span, the abundance
of white shrimp would be expected to fluctuate widely from year to year but
apparently compensating factors are at work; e.g., in 1977 after a massive
winter kill in Georgia coastal waters, when the numbers of spawning white,
shrimp were reduced to 7% of normal, subsequent recruitment into the fishery
was only 40% below normal. For white shrimp in the south Atlantic fishery,
instantaneous mortality rates were 0.02 to 0.25 (fishing), 0.21 to 0.56
Life History - 4 (DRAFT) - Life History
Species shrimp, white
Species Id M070005
Date 26 AUG 96

(natural), and 0.24 to 0.80 (total). Weekly mortalities ranged from 13 to
51%; the lower rates were nearer to reality for both juveniles and adults.

Hurricanes cause major losses of white shrimp in the Gulf of Mexico. A
hurricane striking the Louisiana coast in summer 1957 destroyed large
numbers of white shrimp when salinities increased, cover and food supplies
were destroyed, dispersal and stranding were excessive, and turbulence in
estuaries was high. Hurricane Carla caused a 61% drop in the 1961 Louisiana
catch of white shrimp and Hurricane Camille caused an 88% drop in production
in Mississippi in August 1969. Sudden cold fronts and subsequent declines
in water temperatures have caused mortality and reduced recruitment of white
shrimp in south Atlantic shallow inshore waters; two consecutive mild
winters may be required to support spring harvests in South Carolina.*61*

The Fishery. White shrimp enter the commercial fishery when the gravid
shrimp congregate off the central and southward coast of South Carolina in
April or May and remain in the South Carolina fishery through June or early
July. In Georgia, the white shrimp fishery season opens in June in
territorial offshore waters. Juveniles enter the coastal fishery in August
in South Carolina, Georgia, and northeast Florida. In North Carolina, they
are caught mainly in the fall in the area from Southport to Cape Fear. The
fishery continues through mid-December in South Carolina and to the end of
December in Georgia and northern Florida. Catches in nearshore waters of
Georgia are lowest in June and peak in August and September. Catch per unit
of effort was highest in northern Georgia's offshore waters in late summer
and fall and landings peaked in September and October. As water temperatures
drop, white shrimp move southward and are caught in coastal waters of
extreme southern Georgia in January; however, some may be caught as late as
February depending on the date of closure of territorial waters. Studies
reported that abundance peaked in December and January in northern Florida
from St. Augustine to Cape Canaveral.

Most commercial shrimp catch is made within 9 km of the coast on trawlable
bottoms within the 11-m depth contour. The breadth of the Continental Shelf
within the 11-m (6-fathom) contour is greatest along the northern and
central Georgia shelf, but is narrower along the coast of northeast Florida,
South Carolina, and North Carolina. About 99% of North Carolina's white
shrimp catch was taken in its territorial waters. For the other states, the
percentages were 90% for South Carolina, 85% for Florida, and 59% for
Georgia.

Freshwater inflow is the dominant factor influencing abundance,
distribution, and growth of white shrimp. During the drought and low
freshwater inflow in 1980, the shrimp moved further up estuaries, which
lengthened their residency there and increased mortality. The lower
landings in 1980-81 were caused by low freshwater inflow and low winter
water temperatures.*61*

LIFE HISTORY CODES -
Periodicity: Active in day

REFERENCES FOR LIFE HISTORY- 61
Life History - 5 (DRAFT) - Management Practices
Species shrimp, white
Species Id M070005
Date 26 AUG 96

MANAGEMENT PRACTICES

RESULT MANAGEMENT PRACTICE

Adverse Dredging
Adverse Shoreline modification/development
Adverse Salinity alteration
Adverse Construction of navigational improvements [dams, locks, etc.]
Adverse Applying pesticides
Adverse Applying other toxicants
Beneficial Controlling pollution [thermal, chemical, physical]
Beneficial Controlling refuse disposal [landfills]
Existing Regulating commercial harvest gear types

REFERENCES FOR BENEFICIAL MANAGEMENT PRACTICES - 61

REFERENCES FOR ADVERSE MANAGEMENT PRACTICES - 61

REFERENCES FOR EXISTING MANAGEMENT PRACTICES - 61

COMMENTS ON MANAGEMENT PRACTICES -
The loss of nursery grounds has been considered the major threat to the
white shrimp fishery in the Gulf of Mexico because that is where shrimp are
most vulnerable to habitat disturbance. Studies in Florida, Louisiana, and
Texas identified landfill, dredging, and impoundments as major detriments to
shrimp production. Because of the loss of rich organic material along
bulkheads, shrimp abundance there was reduced to about 1/8 that of nearby
unaltered shorelines. About 18,171 ha of wetlands, 3.5% of the total, were
lost from the South Atlantic coast between 1954 and 1968. Manmade canals in
Louisiana estuaries have increased salinity and adversely affected white
shrimp survival and growth. Increased salinities have favored brown shrimp
over white shrimp in the central-northern Gulf of Mexico. The effects of
pesticides and pollution on shrimp habitat along the gulf coast are also of
concern. Trawl catches of white shrimp dropped below seasonal averages when
dissolved oxygen was below 3.0 mg/l in altered, eutrophic canals associated
with housing developments in West Bay, Texas. Maintaining suitable nursery
grounds ultimately may decide the future of the shrimp resources of the gulf
coast and south Atlantic.*61*

North Carolina, South Carolina, Georgia, and Florida do not permit
commercial trawling in designated nursery areas.*61*

Management Practices - 1 (DRAFT) - References
Species shrimp, white
Species Id M070005
Date 26 AUG 96

References

61* Muncy, R. 1984. Species Profiles: Life Histories and
Environmental Requirements of Coastal Fishes and Invertebrates
(South Atlantic) -- White Shrimp. U.S. Fish and Wildlife Service
Biol. Rep. 82(11.27) pp 19.

References - 1