Aquaculture,
also


known


as

Aqua


farming,


is


the


farming


of


aquatic


organisms

such

as
aquatic

plants.
Aquaculture

involves

cultivating


freshwater


and

saltwater


populations

under

controlled


conditions,


and

can

be
contrasted
with


commercial


fishing,


which

is


the


harvesting

of


wild


fish.


Mari


culture


refers

to


aquaculture
practiced
in


marine

environments


and

in


underwater


habitats.


The


reported


output


from

global


aquaculture
operations
would

supply


one

half


of


the


fish

and

shellfish

that


is


directly

consumed

by

humans;


however,

there
are

issues


about


the


reliability


of


the


reported


figures.


Particular


kinds


of


aquaculture


include

fish

farming,
shrimp

farming,


oyster


farming,


alga

-

culture


(such


as

seaweed


farming),


and

the


cultivation


of


ornamental
fish.

Particular


methods


include

Integrated


multi

-

trophic


aquaculture,


both


of


which

integrate


fish

farming


and
plant

farming.
21st
-

century


practice

.
About

430

(97%)


of


the


species


cultured

as

of


2007


were

domesticated


during


the


20th


century,

of


which

an
estimated

106

came


in


the


decade


to


2007.


Given

the


long

-

term

importance


of


agriculture,


it

is


interesting

to
note

that


to


date


only


0.08%


of


known


land


plant


species


and

0.0002%


of


known


land


animal


species


have
been

domesticated,


compared


with


0.17%


of


known


marine

plant


species


and

0.13%


of


known


marine

animal
species.

Domestication


typically

involves

about


a

decade


of


scientific


research.


Domesticating


aquatic


species
involves
fewer


risks

to


humans

than


land


animals,


which

took


a

large


toll


in


human

lives.


Most


major


human
diseases

originated


in


domesticated


animals,


through


diseases


such

as

diphtheria,


that


like


most


infectious
diseases,

move


to


humans

from

animals.


No


human

pathogens

of


comparable


virulence


have

yet


emerged
from
marine

species.


Harvest


stagnation

in


wild


fisheries


and

over


exploitation

of


popular


marine

species,
combined

with


a

growing


demand

for


high


quality


protein,


encourage


aqua

-

culturists


to


domesticate


other
marine
species.
Definition
According

to


the


FAO,


aquaculture


"is


understood


to


mean


the


farming


of


aquatic


organisms

including


fish,
mollusks,

crustaceans


and

aquatic


plants.


Farming

implies

some


form

of


intervention

in


the


rearing

process


to
enhance

production,


such

as

regular

stocking,


feeding,

protection


from

predators,


etc.


Farming

also


implies
individual

or


corporate


ownership

of


the


stock


being


cultivated.
Aquatic

plants
Microalgae,

also


referred


to


as

microphytes,


or


planktonic


algae


constitute


the


majority


of


cultivated


algae.
Macro
-

algae,


commonly

known


as

seaweed,


also


have

many


commercial


and

industrial


uses,


but


due

to


their
size

and

specific


requirements,


they


are


not


easily

cultivated


on

a

large


scale


and

are


most


often


taken


in


the
wild.

Fish


The


farming


of


fish

is


the


most


common


form

of


aquaculture.


It

involves

raising


fish

commercially


in
tanks,

ponds,


or


ocean


enclosures,


usually

for


food.


A

facility


that


releases


juvenile


fish

into

the


wild


for
recreational

fishing


or


to


supplement


a

species'


natural

numbers,


is


generally

referred


to


as

a

fish

hatchery.
Fish

species


raised


by

fish

farms

include

Bigeye

tuna.


In


the


Mediterranean,


young


Bluefin

tuna


are


netted


at
sea
and

towed

slowly


towards


the


shore.


They


are


then


interned

in


offshore

pens

where


they


are


further
grown

for


the


market.


In


2009,


researchers


in


Australia


managed

for


the


first


time


to


coax

tuna


(Southern
Bluefin)

to


breed

in


landlocked


tanks.
Crustaceans