Transcript FPL302

Shrimp Aquaculture
LaDon Swann
Mississippi-Alabama Sea Grant Consortium
Auburn University
World harvest of farmed marine
shrimp in 1999 was 814,250 MT
Thailand – 200,000 MT
China – 110,000 MT
Indonesia – 100,000 MT
Ecuador – 85,000 MT
India – 70,000 MT
Shrimp Gee-Whiz
• Shrimp, crabs, lobsters and crayfish are
invertebrates referred to as decapods (10 feet)
• Hundreds of species of shrimp inhabit the
brackish and marine waters of the globe.
• Most are rare, very small, or not suitable for
human consumption.
• A shrimp "swims" by quickly pulling its abdomen
in toward its carapace (body). This motion shoots
them through the water. Because of body
configuration shrimp swim backward.
• All farm-raised shrimp and most of the shrimp
caught by fishermen belong to the Penaeidae
family of decapod crustaceans and are referred to
as "penaeids".
Geographic Range
• Marine shrimp are native to all
the oceans and seas of the world
and numerous species are
farmed.
Shrimp Species
• Giant Tiger Shrimp (Penaeus monodon)
– Named for its huge size and banded tail, P. monodon
still accounts for most of the farmed shrimp coming out
of Asia, but it's likely to lose that position to P. vannamei
over the next couple of years.
– Native to the Indian Ocean and the southwestern Pacific
Ocean from Japan to Australia, "tigers" are the largest
(maximum length 363 mm) and fastest growing of the
farmed shrimp.
– They tolerate a wide range of salinities, but shortages of
wild broodstock often exist, captive breeding is difficult
and hatchery survivals are low (20 to 30%). Tigers are
very susceptible to two of the most lethal shrimp
viruses: yellowhead and whitespot.
– Reddish-orange on the sides and pearly-white on the
top and bottom
Shrimp Species
• Western White Shrimp (Penaeus vannamei)
– Native to the Pacific coast of Central and South America,
– Leading farm-raised species in the Western Hemisphere,
representing more than 95% of production.
– Because vannamei feeds on organisms which grow
naturally in the pond, it is cheaper to feed than
monodon.
– White shrimp can be stocked at small sizes, have a
uniform growth rate and reach a maximum length of 230
millimeters.
– They breed in captivity better than monodon
– Hatchery survivals are high, from 50 to 60%. Throughout
Latin America, hatcheries maintain captive stocks of
vannamei broodstock.
– Look for it to become the dominant species in Asia over
the next couple of years.
Shrimp Species
• Chinese White Shrimp (Penaeus chinensis)
– Native to the coast of China and the west coast of
the Korean peninsula.
– Chinese white shrimp grow better in lower water
temperatures (down to 16 degrees Celsius) than
vannamei and monodon
– Tolerate muddy bottoms and very low salinities—
and, unlike the above species, Chinese white
shrimp readily mature and spawn in ponds.
– On the negative side, they have a high protein
requirement (40 to 60%), a small size (maximum
length of 183 millimeters), and a lower meat yield
(56%) than monodon (61%) and vannamei (63%).
– Also, chinensis appears to be more susceptible
to viruses than vannamei.
Shrimp Species
• Freshwater Prawns (Macrobrachium spp.)
– World production of farmed prawns has risen to around
200,000 metric tons, worth about a billion dollars, most
of it from Bangladesh and China.
– The genus Macrobrachium, which includes about 200
species, almost all of which live in freshwater for at least
part of their life cycle, native to all continents except
Europe.
– The favored species for farming has always been M.
rosenbergii, sometimes called the "giant river prawn" or
the "Malaysian prawn
– In the United States, there are more than 500 small
freshwater prawn farms (M. rosenbergii).
– Resemble giant tiger shrimp, but they're bigger,
chunkier, lighter in color, and their shells are always on.
– If the bottom part of the shell on the second tail segment
overlaps the shell on the first and third segments, it's a
freshwater prawn.
Shrimp Species
• Brown shrimp (Farfantepenaeus aztecus)
– Found in Atlantic and Gulf of Mexico
– Most abundant of the three Gulf Shrimp
– The brown shrimp is closely related to the pink
shrimp
– The brown shrimp is found in murkier and
often deeper water.
– Spawn offshore from November to April.
– Young adults move out of protected marsh
areas from May to July.
• Excellent bait species candidate
Shrimp Species
• White shrimp or Atlantic Shrimp
(Litopenaeus setiferus)
– Found in Atlantic and Gulf of Mexico
– Second most harvested species in the three
Gulf Shrimp
– The white shrimp is generally found in waters
that are muddier, shallower, and less salty than
waters where pink shrimp and brown shrimp
live
– Spawn offshore from March to October
– Juvenile whites tolerate low salinity better than
browns
– Young adults migrate offshore from July to
November
Shrimp Species
• Pink shrimp
(Farfantepenaeus duorarum)
– Found in Atlantic and Gulf of Mexico
– Least abundant of the three Gulf Shrimp
– This species generally lives in clear
waters.
– Spawn offshore from May through
November
– Migrate out of marshes from April to
September
Gulf Shrimp Identification
• Brown
– Groove on either side of spine
on back of head
– Similar groove on the last
body segment before the
tail segment (A)
A
• Pink
– Groove on either side of spine
on back of head
– Similar groove on the last body
segment before the tail segment
– Dark or pinkish blotch on each
side of body between carapace
and tail (B)
• White
– No grooves on spine or last
segment before tail (C)
B
C
Penaeid Shrimp Life Cycle
Shrimp have a maximum life span of about 24 months.
Larval Staging
• Penaeid Shrimp pass through three
larval stages
– Nauplii
– Zoeal
– Mysis
• Postlarval (PL) follows larval stages
– Look like shrimp by this stage
Nauplii Stage
• Six sub-stages
– May lose 25%
– Nauplii sub-stages
take approximately 48
hours
• 36-51 hour range
depending on
temperature
– Begin feeding at N6
Zoeal Stage
• Zoea feed on
phytoplankton
• Three zoeal substages
– 120 hrs
– 36-48 hrs per stage
Mysis Stage
• Look like adult
shrimp
• Begin to swim
backwards
• Three substages
– Each last 24 hrs
Post Larvae
• Postlarvae (PL)
– PL1: one day PL
• 0.0008 g/PL1
– PL 20: 20 day PL
• 0.02 g/PL20
• Swimming seta present on pleopods
• Reared in tanks or raceways
• Stocked in ponds beginning around
PL15-PL20.
Larval Feeding
Zoea
• Isochrysis
– Brown algae
– (3-5 mm)
Isochrysis
• Chaetoceros
– Diatom
– (4-6 mm)
• Tetraselmis
• Green algae
• (10-15 mm)
Chaetoceros
Tetraselmis
Larval Feeding
Mysis
• Feed large algae
cells early on
• Switch to artemia
(brine shrimp) for
later stages
6
5
4
3
2
1
0
Artemia/ml
Late Z3-MI
MII-MIII
M I- M II
MIII-PL
Larval Feeding
Postlarvae
• Artemia
– 6/ml at PL4
decreasing to 0 by
PL11
• Formulated diet
– 35% protein
– 3% fat
• Feeding rate
– 200% bwt/day
– 50% X 4 times per
day
General Shrimp Farming Concepts
• Marine shrimp are grown in earthen
ponds located in coastal areas of
countries with tropical and
subtropical climates.
• Ponds are filled with saltwater
pumped from estuaries and oceans.
Small shrimp reproduced and raised
in captivity are stocked into the
ponds and are ready for harvest in 90
to 120 days.
Farm Location
• Locate ponds close to good quality
brackish water
– 5-30 ppt
– Farms can be inland if suitable aquifers
are available
• Soil should have high clay content
– 25%
• Water table should not be within
three feet of surface
Farm Permits
• Construction permits from Corps
of Engineers
• Aquaculture Permits from state
• Local permits
Farming Strategies
• Extensive
– Large ponds
– Low stocking densities
– Little management or investment
• Semi-Intensive
– Falls in between the two extreme of intensive and
extensive
• Intensive
–
–
–
–
Smaller ponds
Aeration
High stocking densities
Feeding
Pond Construction
•
•
•
•
Ponds range in size from 1-10 acres
4-7 feet deep
Gentle bottom slope
Well maintained levee
Gulf and Inland Shrimp Species
• Food
– Western white shrimp
• Penaeus vannamei
– Northern white shrimp
• Litopenaeus setiferus
– Freshwater shrimp
• Macrobrachium spp.
• Bait
– Brown shrimp
• Farfantepenaeus aztecus
Stocking
• Stock with post larval
shrimp (PL)
– ½ inch in length
– Stock 40,000-80,000
PLs per acre
– Havest 3,000lbs/acrea
Management
• Fertilize ponds prior to stocking
• Feed good quality shrimp feed
– 35% protein
– 3-5% bwt per day
• Provide aeration when necessary
Harvest
• Harvest in October
• 22-36 count
• Drain and seine
ponds
• Direct market or sell
to processor
Common Problems
• Shortage of PLs
• Shrimp viruses