L12: Aquaculture 101 (Francis-Flloyd) Flashcards
1
Q
aquaculture
A
the controlled rearing of aquatic organisms
-fastest growing animal industry
2
Q
where does most aquaculture production occur?***
A
Asia (89% of global production)
3
Q
areas of big salmon production
A
Chile
Norway
Canada
4
Q
primary aquaculture product in China
A
carp (also shrimp)
5
Q
what is Florida’s biggest industry?***
A
production of tropical fish for pet trade
6
Q
Top 6 industries in FL***
A
Tropical Fish Aquatic Plants Clams (<-- largest food fish production is CLAMS!***) Alligators Catfish Other food fish
7
Q
chars. of EXTENSIVE culture technique***
A
- focuses on fishery management rather than aquaculture management
- low biomass: volume ratio (low stocking density)
- minimal management required (NO feed, aeration needed)
8
Q
chars. of INTENSIVE culture technique***
A
- management becomes more like traditional farm management (»>1000lb/acre)
- problems: crowding, water quality, nutrition, infectious disease
- feeding, water quality management, aeration required
9
Q
tidal flush
A
using the natural flow of tides to circulate water in aquaculture enclosures
10
Q
advantages of EXTENSIVE production**
A
- little to no investment equip/feed
- fish can be trapped
- water quality probs. minimized
- natural food available in pond
- can be used as source of protein from community managed ponds in region``
11
Q
livebearers
A
fish that produce live young and don’t lay eggs
ie swordtails, guppies, mollies, platies
12
Q
tradition broodstock production
A
- stock broodfish into fertilized pond
- offer very low quality feed in small amounts
- place baited traps to harvest big enough fish
- NO control of genetics or # harvested!
13
Q
Tale of the swordtail***
A
- lack of selectvie breeding –> poor swords, dec. value
- many farms now raise these fish intensively to control quality and improve selective breeding practices
14
Q
adv. of INTENSIVE production
A
- more control, elimination of predation
- massive inc. in production
15
Q
disadv. of INTENSIVE production
A
- inc. risk of disease and disease transmission
- system failure –> catastrophic loss
- high start-up and operating cost
- complete diet required
16
Q
Intensive production: egg layer production
A
- initial rearing in hatcheries
- grow out in ponds/tanks
- biosecurity critical
17
Q
types of production systems used for aquaculture production in the U.S.***
A
- Earthen ponds (54%) –> channel catfish***. hybrid striped bass, shrimp
- raceways (rainbow trout)
- cages or net pens (salmon)
- re-circulating tank systems (Tilapia)
- underwater lease (clams)
18
Q
advantages of pond production
A
- free/cheap water
- filtration system not required
- some natural food available
19
Q
disadvantages of pond production
A
- minimal control of env.**
- predation can exceed 70%
- difficult to maintain inventory
- “Off Flavor” hard to control
20
Q
chars. of Earthen ponds
A
- intensity of management determined by stocking density
- dissolved oxygen often limiting
- minimal control of rearing conditions
- most common method used for production aquaculture in U.S.
21
Q
ideal shape of earthen pond***
A
cake pan shape!
-narrow deep ponds don’t do well due to stratification
22
Q
adv. of raceway prod. systems
A
- often use “free” water from river or other source
- use high flows instead of investment in filtration
- relatively inexpensive
23
Q
disadv. of raceway prod. system
A
- poor control of water source
- introduce dz and contaminants if using surface water
- crowding facilitates rapid spread of dz
- txs can be difficult b/c large volumes of water used
24
Q
adv. of Cage Culture
A
- tidal flush can be used
- risk of contam. or dz from local water
- easy to harvest
25
disadv. of Cage Culture
- controversial in populated areas
- exposure to wild fish (dz)
- potential for contam. from local water
- susceptible to storm damage
- predation
- concern for damage to local env.
- very crowded, potential for rapid spread of dz
- difficult to tx
26
adv. of Re-circulating Systems
- complete control of env.
- elim. of predation
- very efficient grow out for suitable species (ie. tilaia do well, catfish do not)
- tx easier and less expensive than other systems
27
disadv. of Re-circulating Systems
- very high investment
- high risk (catastrophic failure)
- intensive management required
- expensive to operate/maintain
- biosecurity critical
28
chars. of All-in-all-out production strategy
- system drained at end of prod. cycle
- all fish removed
- disinfection and removal of sediment and muck
29
chars. of Continuous production strategy
- system rarely drained
- following harvest, "top off" pond with fingerlings to replace rish removed by harvest
- industry standard for catfish production
30
adv. of Continuous Harvest
- no "down time" to dry out pond
| - practical for large ponds
31
disadv. of Continuous Harvest
- loose track of inventory
- pond banks erode
- massive accumulation of organic matter
- when maintenance does occur, it is major
- major dz control difficult
32
adv. of All-in-all-out Harvest
- better control of inventory
- avoid build up of organic material
- can produce multiple crops in same pond
- better biosecuriy
33
disadv. of all-in-all-out Harvest
- labor intensive
| - more effluent (waste discharge) from pond
34
most important aquaculture industry in U.S.***
channel catfish
| -NOT a big business in FL
35
special health concerns for channel catfish
```
Water quality (low dissolved oxygen, "off flavor", ammonia/nitrite)
Infectious Dz
```
36
chars. of Tilapia**
- very hardy
- omnivorous
- thrives on low quality feed
- exotic to FL
- freshwater
- THERMAL LIMITED. Temps <50 F is FATAL**
37
#1 fin fish produced in China
Carp/Koi
38
Euro style of Koi show
fish isolated from eachother for judging
39
Japanese style of Koi show
fish placed in same tub for judging
| -prob = dz trans.
40
special health concerns for carp/koi
```
Viral disease:
-Spring Viremia of Carmp (SVC)) --> FAD
-Koi Herpes Virus (KHV) --> endemic to U.S.
Bacterial dz:
-Aeromonas salmonicida
```
41
Koi Herpes Virus***
- aka Cyprinid HV 3
- endemic to U.S.
- warm water disease
- primary target: gill
- REPORTABLE (but no action taken)
42
Spring Viremia of Carp***
- FAD
- cool water disease
- non-specific signs
- REPORTABLE: depopulation required!
43
basic components of fish health management program
- water quality/life support
- nutrition
- sanitation
- quarantine/biosecurity
44
Basic Water Quality Parameters
- dissolved oxygen**
- total ammonia nitrogen (TAN)**
- unionized ammonia nitrogen (toxic ammonia)**
- temp
- CO2
- pH
- total alkalinity
- total hardness
- nitrate, nitrite
- salinity
45
sources of dissolved oxygen
- diffusion (atmospheric)
- agitation (wind/wave action of "bubbler")
- photosynthesis ("green" water only)
46
diurnal oxygen cycle
highest D.O. at dusk, lowest at dawn (rises during the day, falls over night)
47
thermocline
area of rapid temp. change that separates warm and cold water
-occurs in stratification
48
issue of stratification
- cold water sinks and thermocline develops
- oxygen demand builds up in cold water
- when water mixes in Turnover, O2 is diluted to all stratums
- catastrophic fish kill possible (ie. following storms)
49
The Nitrogen Cycle
1) fish respiration/decomposing organic matter/excess food/fish excreta/anaerobic bacteria --> ammonia
2) bacteria remove ammonia and produce nitrite
3) bacteria convert nitrite to nitrate
4) nitrate builds up or feeds anaerobic bacteria or fertilizes plants
50
as pH increases, ammonia becomes more toxic to fish***
:)
51
adverse effects of ammonia
- osmoregulation affected
- blood pH increases
- inc. O2 need
- dec. O2 transport
- chronic low lvl ammonia --> inhibited growth, inc. susceptibility to dz
52
How to avoid ammonia toxicity in water garden
- reduce stocking density
- don't overfeed
- maintain optimal DO
- add biofiltration
- water change
53
how to avoid ammonia toxicity in pond
- reduce stocking density
- harvest frequently
- don't overfeed
- maintain optimal DO
- water change
