Term
| How is production success measured in aquaculture? |
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Definition
| efficiency of conversion of feed/food inputs into biomass |
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Term
| Describe the flow of energy in an ecosystem |
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Definition
solar energy
primary producers
herbivores
carnivores
decomposers
nutrients |
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Term
| How are different aquaculture systems defined? |
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Definition
| based on the contribution of natural food sources & how much human input there is |
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Term
| What are the 3 types of aquaculture? |
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Definition
extensive
semi-intensive
intensive |
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Term
| What is semi-intensive aquaculture? |
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Definition
when the natural production of food is stimulated or supplemented by inputs added by humans
e.g. fertilizer, feed supplements added to water but fish also rely on naturally present food sources |
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Term
| ______ aquaculture relies solely on the natural food web |
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Definition
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Term
| What is integrated fish farming? |
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Definition
production of two species at once, with inputs/outputs that complement each other
e.g. rice & fish, horticulture & fish, ducks & fish |
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Term
| What is the best way to maximize productivity when using an extensive system? What is this known as? |
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Definition
raise multiple species that can feed on the products of one another
POLYCULTURE |
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Term
| Where does the majority of global aquaculture take place? |
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Definition
| Asia (specifically China) |
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Term
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Definition
| nets planted into the floor of a pond, fish are kept in the net and fertilizer or feed is added (semi-intensive farming) |
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Term
| How has global aquaculture production changed in recent years? |
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Definition
| production has become intensive. previously, most industries relied on wild populations |
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Term
| How has aquaculture production changed in China in recent years? |
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Definition
1950's: extensive/semi-intensive, low production rate, community-managed fish
1980s - switch to privatized production, intensive systems, rapid spike in production |
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Term
| Why is stocking density of intensive cages so high? |
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Definition
| the system is expensive to set up, so want to maximize return on investment by raising as many fish as possible |
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Term
| Why are salmon cage farms so highly mechanized? |
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Definition
| often in remote locations, obtaining staff, feed etc frequently is difficult. the more robotic the better |
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Term
| Why is feeding aquaculture species a challenge? |
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Definition
-digestive systems undergo significant changes from larvae to adults
-difficult to find live prey which can be efficiently cultivated & meets nutritional reqs of the fish |
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Term
| Larval aquatic animals are often fed.... |
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Definition
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Term
| Why is raising rotifers as a live prey source difficult? |
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Definition
| undergo lots of changes in their life cycl |
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Term
| What is the nutritional 'gold standard' live prey feed in aquaculture? Why aren't they fed very often? |
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Definition
copepods
very difficult to cultivate |
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Term
| Why are brine shrimp commonly used as live prey? what is the issue? |
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Definition
-cysts can be stored in a can for years, then stimulated to develop when introduced to salt water
problem: they contain none of the required fatty acids for fish |
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Term
| Crustacean larvae are often fed.... |
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Definition
| egg protein, mixed with water to form paste |
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Term
| What are the cons to feeding live prey? |
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Definition
difficult to maintain
those that are easy are not nutritionally balanced
they can carry disease |
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Term
| What is the challenge in feeding dry feed to fish? |
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Definition
| the particles may not be perceived as food, need to 'train' the fish to eat it by gradually switching from live prey to pellets |
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Term
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Definition
FOOD
-self seleced
-natural
-high degree of sanitation
FEED
-humans decide what animals will eat
-artificial
-lower degree of sanitation |
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Term
| Why is feeding trash fish not ideal? |
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Definition
-rot quickly
-can be very polluting
-source of disease |
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Term
| What is a popular method of feeding eels in Japan? |
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Definition
| cooking trash fish, slaughter house byproducts, grains etc. & turning into a paste |
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Term
| What is a meat-meal mixture? |
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Definition
| blending meat byproducts with dry mixture to create a moist feed |
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Term
| How can farm-made feed be made more stable |
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Definition
| dry it in sun, will allow for a few days' storage instead of needing to be fed right away |
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Term
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Definition
| all ingredients are mixed to form paste, forced through an extruder under height heat/pressure, cut into pellet shapes, dried & oils added. |
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Term
| What is the advantage to extruded feed? |
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Definition
| much safer, can be made to float, prolongs shelf life |
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Term
| If your fish are kept in murky water, how should they be fed? |
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Definition
| hand fed using a feed that floats, so fish will come to surface and you can assess their health & feed consumption |
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Term
| What is a con/pro to demand feeders? |
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Definition
fish may consume far more feed than they need
*can also be a pro as ad-lib feeding can increase growth rate, to some degree |
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Term
| If you are using a mechanized feeding system in a remote area, how can you monitor intake |
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Definition
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Term
| Why are feeding trays used? What is the con? |
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Definition
can monitor intake, make sure feed isn't going to waste or being fed in excess
con: manual labour |
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Term
| What characteristics should aquaculture feeds have? |
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Definition
1. size, stability, palatability & appearance appropriate for species
2. cost effective
3. meet nutritional requirements
4. can be stored, transported, convenient to use, consistent quality
5. fish produced should be safe, acceptable and attractive to consumers
6. sustainable (environmental considerations) |
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