http://srac.tamu.edu/index.cfm?catid=9
1. Read the following online:
2. SRAC pub: 2403 (crawfish)
SRAC 0483 Freshwater Prawns: Biology and Life History
SRAC 0484 Pond Production of the Freshwater Prawn in Temperate Climates
SRAC 4830 Economics of Freshwater Prawn Farming in the United States
3. Hybrid striped bass:
SRAC 0300 Hybrid Striped Bass: Biology and Life History
SRAC 0301 Hybrid Striped Bass: Hatchery Phase
SRAC 0302 Hybrid Striped Bass: Fingerling Production in Ponds
SRAC 0303 Hybrid Striped Bass: Pond Production of Foodfish
4. Trout:
SRAC 0220 Trout Production: Handling Eggs and Fry
Trout and Salmon Culture
Salmonid Life Cycle
Commonly Cultured Trout
• Rainbow Trout
Oncorhynchus mykiss
• Brown Trout
Salmo trutta
• Brook Trout
Salvelinus fontinalis
Trout Culture
Stages of Culture - Trout
•
•
•
•
•
•
Broodstock
Spawning
Egg incubation
Fry culture
Fingerling production
Growout
Broodstock
• Females are 2 to 3 years old
– Can be used for more than one year but may
have decreased egg quality and quantity
• Males are 2 to 3 years old
– Can be used several times in one spawning
season but not for more than one year
Dry Spawning
Eggs
• “Green eggs” = eggs from 48 hours postspawn to eyed stage
• Can be shipped in plastic eggs at 38°F
• Ship eggs wrapped in damp cheese cloth
• Chill with ice and let water drip onto eggs
Egg Incubation
Trout – Sac Fry = Alevins
Size Grading
Trout Fingerling Production
Trout Growout
• Raceways
• Ponds
• Cages
Tri-Omega Trout Farm, Pisgah National Forest in Transylvania, NC
Trout Growout
• Raceways
• Ponds
• Cages
Tri-Omega Trout Farm, Pisgah National Forest in Transylvania, NC
Trout Raceways in NC
Trout Raceways In Idaho
Trout Pond Culture
Trout Tank Culture
Marketing Trout
• Fee fishing
• Live hauling
• Filet products
Fee Fishing
Live Hauling
Fillet Products
Salmon Culture
There are six species of salmon in the Pacific
Northwest. The largest salmon, the Chinook, can
reach over 6 feet in length and weighs over 100
pounds.
Atlantic Salmon stock enhancement - collection of wild broodstock
The Salmon
In the fall, salmon deposit
eggs in the gravel of
flowing streams.
Eggs hatch in the
spring, and the
alevin grow quickly.
Later, the
fingerlings continue
to grow toward
maturity in the
streams near their
birthplace.
When they become
strong enough to
swim in rushing
currents, and quick
enough to escape
their enemies, the
salmon begin
migrating to the sea.
Life Cycle
After spawning (laying eggs),
the salmon die sometimes
inches from where they were
hatched! Amazing instincts!
As they get closer to
their spawning grounds,
salmon change in their
appearance. Some salmon
travel over 1000 miles to
lay their eggs.
Salmon can grow to be
over 100 pounds as they
feast in the nutrientrich waters of the
ocean. When full grown,
the beautiful, silvery
fish begin their
migration back to the
waters of their birth.
Commonly Cultured Salmon
• Atlantic Salmon
Salmo salar
• Chinook Salmon
Oncorhynchus
tshawytscha
• Coho Salmon
Oncorhynchus kisutch
• Pink Salmon
Oncorhynchus
gorbuscha
Atlantic salmon hatchery
Stages of Salmon Culture
•
•
•
•
•
Spawning
Egg incubation
Fry culture
Fingerling production
Growout
Salmon Egg Incubation
Sac Fry Culture
Alevin
Tiny alevin grow quickly after being hatched.
When they are as long as your fingernail,
they are called fry, and look like real fish!
When they get to be about as long as your
longest finger, they are given a new name -smolt. As the smolt grow, they eventually
begin their migration to the ocean.
Ocean
Bound!
Smolt
Salmon Fingerling Production
Salmon Fingerling Production
Salmon Growout
Hills Island Salmon Farm, Canada
• Extensive
• Net Pens
Salmon - Extensive Culture
• Culture fingerlings in tanks
• Stock fingerlings (smolts) into native streams
• Fish will migrate to the ocean and undergo
smoltification
• Fish will live in open ocean for approximately 3
years
• Fish will return to stream they were planted
(chloramine-T, Seattle)
• Can be harvested when they return and before
they die
• Approximately 1 in 1000 return
Salmon - Net Pen Culture
Salmon Net Pens
• Stocking density 8 – 14 kg/m3, but 75 kg/m3 possible!
• Feeding by hand, or electronic (SONAR)
• Atlantic salmon ~80% of net pens in the Pacific Northwest
and Canada.
• Why Atlantic salmon in Pacific????
– Better FCR, higher survival, better dressout %.
• Escapees of Atlantic salmon into Pacific Ocean problem?
– Not yet! Escapees experience
high mortality, poor
reproduction, do not spawn
with Pacific salmon
Salmon Processing
Marketing Fillets
Figure 1.2.10
Total finfish aquaculture production by major species groups in 2000
CATFISHES
(values expressed as % by weight)
Total production 23,067,973 metric tons & valued at US $ 31,565,104,100 in 2000
FILTER FEEDING CYPRINIDS
MARINE FISHES
EELS
MILKFISH
SALMONIDS
CATFISH
TILAPIA
OTHER
FRESHWATER FISHES
PELLET FEEDING CYPRINIDS
Credits
Pictures and diagrams found in this
photo essay are courtesy of:
•The Alaskan Department of Fish and Game
•The Washington Department of Fish and Game
•The Army Corps of Engineers
•The US National Marine Fisheries
These salmon are on their way to the ocean where they
may live for 1-5 years, depending on the species, before
returning to the rivers and streams to spawn (lay eggs).
Only one salmon out of a thousand salmon survives to
return to the river to spawn. What are some possible
reasons why such a small percentage of salmon actually live
long enough to lay eggs?
Going home!
These salmon are on their way back to the waters of their
birth. Scientists do not know how salmon find the exact
location of their birthplace, but their sense of smell (and the
chemical signature of the waters) is an important cue.
Along the way are
many hazards –
some more hungry
than others!
Replenishing Nutrients
When salmon die after spawning, they
provide nutrients to plants and
animals near the rivers in which they
swam. It has been found that 20 % of
the nitrogen (an important element
for all living things) in evergreen
trees that grow next to salmon
spawning waters in Alaska actually was
carried upstream with salmon. These
nutrients are essentially transported
from the ocean to the headwaters by
the salmon.
Rainbow Trout culture
By
Leonard Lovshin
Department of Fisheries and Allied Aquaculture
Auburn University, Alabama, USA
Distribution
1. Native – Western U. S., western Canada,
Alaska and Western Pacific.
2. Introduced – Eastern U. S. and most of the
temperate
climate world.
Oncorynchus mykiss
Rainbow trout live their entire life cycle in
fresh water
Steelhead are a rainbow trout that lives most
of its life in the ocean but returns to fresh
water to spawn.
Male
Female
Food Habits – insects, crustaceans and fish
Water Quality
1. Dissolved oxygen – above 5 mg/l
2. Needs water of good quality
Sexual maturity – 2 to 3 years old
Water temperature
Should not be
0
above 22 C
and ideal for
good growth
is 13 to 180C
Rainbow trout are a popular sport fish.
The world record taken by rod and reel
is 19.1 kg
Reproduction
1. Nature - Spawns in the Spring and needs
water below 120C for 6 months to produce good
quality eggs.
Females spawn eggs over gravel beds in stream riffle
areas.
Reproduction
Captivity – Eggs are stripped from ripe females
and sperm is stripped from males and mixed in a
bowl.
Water upwelling incubator
Eggs are artificially
incubated and will hatch
in 50 days at 70C and 20
days at 150C.
Recently Hatched Trout Fry ( Alevins )
Fry are large when they
begin to swim and can be
fed with powdered
formulated diets at first
feeding.
Culture
1. Most trout are raised in raceways with abundant
flowing water. Some trout are raised in earthen
ponds with water exchange and in cages.
2. The environment, stocking density, fish growth and
feeding rate are highly controlled.
3. Trout culture is divided into 3 types depending on
the
trout harvested.
a. pink pan-sized
b. white pan-sized
c. salmon trout; larger than 1 kg
Pink fleshed trout
Carotenoid
pigments
Earthen raceways
and feeding trout
in Chile. Notice
netting to protect
against birds.
Concrete
raceways and
feeding trout in
Brazil
Idaho is the
leading producer
of trout in the U.
S.. Most trout
are farmed along
the Snake River
valley.
Springs flowing into
the Snake River in
Idaho
Earthen Raceways with demand feeders in Idaho.
Trout are fed with a nutritionally complete, high
protein, floating diet.
Trout triggering
a demand
Concrete raceways along
the Snake River in Idaho
Water is reoxygenated
as it falls from higher
to lower tanks
Large Trout Raceway Farm in Idaho
Trout Raceways in Idaho
Trout are graded to maintain
uniform size in a raceway
Trout harvest in Idaho
with a fish pump.
Trout harvest with lift
basket in North
Carolina
Sludge Removal from a
Raceway Effluent
Settling Tank
Rainbow trout are often raised in
cages to weights larger than 1 kg
Market Products
1. Whole, gutted
2. fillets
Golden
variety of
rainbow trout
World Production of Rainbow Trout in 1999:
418,654 metric tons
Leading Producers in 2001:
1. France – 47,500,000 kg
2. Norway – 60,000,000 kg ( all large trout, >1 k
3. Italy – 44,000,000 kg
4. Denmark – 37,000,000 kg
U.S. annual production: 56.9 million lbs
(2001)
9 % of total finfish production in U. S.
State
Production, lb
Price/lb
39,500,000
0.87
2. N. Carolina
5,550,000
1.10
3. Washington
2,590,000
1.00
4. California
2,500,000
2.05
5. Pennsylvania
1,640,000
2.50
1. Idaho
Advantages
1. Best cold water fish available
2. Grows well
3. Ease of reproduction and fingerling production
4. Good quality flesh
5. Easy to harvest
6. Stock at high densities
7. Accepts pelleted diets
Disadvantages
1. Not tolerant of warm water temperatures
2. Not resistant to poor water quality and disease
3. Feeds high on the food chain