13. aquaculture

Question 1

aquaculture

Answer 1

farming of aquatic organisms

ex. Fish, Mollusks, Crustaceans, Reptiles, Aquatic plants

Question 2

what % of animal protein comes from marine sources?

Answer 2

~20%

Question 3

best choices of fishing methods

Answer 3

hook and line
trolls
harpoons
pot and traps

Question 4

worst way of fishing methods

Answer 4

drift nets

dynamite and cyanide

Question 5

how are fishing methods rated?

Answer 5

selectivity
bycatch rate
environmental damage

Question 6

not-so-good way of fishing methods

Answer 6

midwater trawls
longlines
gill nets
dredges

Question 7

sustainable fishing (3)

Answer 7

science and technology - scienced-based catch limits and less destructive fishing methods

policy and enforcement- reduced illegal fishing

informed markets- certification and traceability

Question 8

Is the US a leading global importer of fish & fishery products?

Answer 8

yes, 91% of our seafood originates from abroad

Question 9

supplying

Answer 9

US is a major supplier of advanced
technology, feed, equipment, & investment to other
producers around the world.

Question 10

how much seafood consumed worldwide is produced by aquaculture (vs fishing)?

Answer 10

more than 50%

Question 11

history of aquaculture

Answer 11

mid-1800s - started out as recreational fishing
after WWII - production og baitfish
1980s- Aquaculture became an important food
supplier

Question 12

milt

Answer 12

fish sperm

Question 13

broodstock

Answer 13

mature/adult animals kept for reproduction

Question 14

spawn

Answer 14

to produce eggs, sperm, or young

Question 15

spat

Answer 15

young shellfish

they settle down and attach to objects

Question 16

fry

Answer 16

young fish

Question 17

hatchery

Answer 17

(1) Maintain the broodstock
(2) Spawn the broodstock
(3) Hatch fertilized eggs to produce larvae
(4) Nurture larvae to the appropriate stage to move to the nursery

Question 18

nursery

Answer 18

Raise the young fry (fish), postlarvae (shrimp, prawns),
or spat (shellfish) to the juvenile stage

Question 19

water and pathogens

Answer 19

pathogens are much more likely to survive in water

drying is a form of sterilization

Question 20

water quality

Answer 20

temperature
salinity
dissolved oxygen
ammonia
nitrites
pH
alkalinity
hardness
toxins

Question 21

Dissolved oxygen

Answer 21

mg/l or ppm
sources are surface absorption from the air and aquatic plants release O2 as a byproduct of
photosynthesis.
low DO kills more fish than all other problems
air = 20% oxygen (200,000 ppm)
pond - 3 to 12ppm

Question 22

hardness

Answer 22

measure of the divalent ions (salts with two positive charges: Ca2+, Mg2+, Fe2+)

Question 23

osmoregulation

Answer 23

maintaining precise levels of internal salts for normal heart, muscle and nerve function

Question 24

levee ponds

Answer 24

standing water impoundments built by excavating the
pond area to a shallow depth and using the soil
obtained to build a perimeter of levees or dikes
- O2-available all
the way to the
bottom.
- Costly to build.
- Need wells or other
water sources.

Question 25

watershed ponds

Answer 25

Standing water impoundments built by
damming ravines or small valleys.
- Lack of O2 at greater depths
- Less costly to build.
- 5-30 acres of watershed to
supply water for 1 acre of pond.
- Can’t refill the pond at will.

Question 26

Raceways & flow through tanks

Answer 26

Long channels or tanks with continuous flow of
fresh water.
- Easy to handle &
harvest fish.
- Easy to manage waste.
- Difficult to find sites
with abundant water
at the right temp

Question 27

recirculating system

Answer 27

Tank systems which filter and re-use water

• Control environment
• Locate almost anywhere
• High production cost
• Need constant attention

Question 28

cages or net pens

Answer 28

Floating enclosures (+ feed)
- Existing water
(lakes, rivers, & off-coasts)
- Vulnerable to disease,
environment, theft,
moderately low oxygen,
and escape

Question 29

health management

Answer 29

• Housing
  -Water & Feed Quality
  -Stocking Density (stress)
  -Infectious Diseases – bacteria, viruses, parasites
  Treatments:
  Dipping / Bathing
  Tank flushing
  Feeding
  Injecting

Question 30

catfish production in the US

Answer 30

location: 94% of total US sales: MS>AL>AR>TX

Question 31

channel catfishing production

Answer 31

Spawning (spring) may be in open ponds where
adults are stocked in male:female ratios of 1:1 to 1:4.
Catfish prefer to spawn in relatively dark & protected
surroundings
Eggsmay be allowed to hatch in the spawning pond
(—adults are moved to another pond) OR eggs are collected every 3 to 4 days & moved to a
hatchery.

Question 32

sac-fry

Answer 32

have an attached
yolk-sac, so they don’t
need extra feed for 24-48
hours.

Question 33

swim-up fry

Answer 33

Once the yolk-sac is
absorbed and the fish start searching for food
moved to rearing trough

Question 34

fingerling

Answer 34

young fish
Once fingerlings are 4 to 6
inches long, they are move to grow-out ponds

Question 35

harvest weight of catfish

Answer 35

1.25 lb/ 18 months

Question 36

seine

Answer 36

drag-net
should be made of nylon or polyethylene twine
and coated with plastic, tar or petroleum based
materials to prevent
catfish spines from
becoming entangled
in the net.