fish farming

Question 1

what are fish farms ways of?

Answer 1

raising large numbers of fish in a small space to provide food (protein) for humans

Question 2

what are the advantages of fish-farming over wild-fishing? (selective breeding)

Answer 2

the ability to selectively breed fish to ensure high quality, fast-growing fish

Question 3

what are the advantages of fish-farming over wild-fishing? (protection)

Answer 3

the ability to protect against predators

Question 4

what are the advantages of fish-farming over wild-fishing? (water quality)

Answer 4

the ability to control water quality (many wild-caught fish have pollutants such as mercury in their flesh)

Question 5

what are the advantages of fish-farming over wild-fishing? (feeding)

Answer 5

ability to control feeding to ensure rapid growth

Question 6

what methods are used in fish farms to ensure high yield?

Answer 6

the control (and maintenance) of water quality
the control of intraspecific predation
the control of interspecific predation
the control of disease
the control (and removal) of waste products
the control of the quality and the frequency of the feeding
the use of selective breeding

Question 7

what is the problem with interspecific competition?

Answer 7

different species will compete for food and some species may be wiped out

Question 8

what is the problem with predation?

Answer 8

carnivorous species will prey on other fish

Question 9

what does maintenance of water quality mean?

Answer 9

water is filtered to remove waste and harmful bacteria to prevent diseases
water is also cleaned to maintain high levels of oxygen for aerobic respiration

Question 10

what does the control of intraspecific predation mean?

Answer 10

fishes are separated by size and age so that they don’t eat eachother or fight

Question 11

what is intraspecific predation?

Answer 11

predation within the same species

Question 12

what is interspecific competition?

Answer 12

predation between different species

Question 13

how is interspecific competition resolved?

Answer 13

different species of fishes are separated by fences, nets and tanks to prevent fighting

Question 14

how is control of disease implemented?

Answer 14

antibiotics are given to fish to prevent disease which might otherwise spread quickly due to their close confinement, increasing the chance of survival
they are kept in small numbers to minimise the spread of diseases

Question 15

how is removal of waste products implmented?

Answer 15

water can be filtered to remove waste products such as faeces and sewage
fences, nets and tanks are cleaned or location of fish can be changed to ensure clean water

Question 16

how is quality and frequency of feeding implemented?

Answer 16

fish are fed food that is high in nutrients to ensure fast growth
they are fed frequently in small amounts so they do not overeat or start eating eachother

Question 17

how is use of selective breeding implemented?

Answer 17

fish are separated by gender so that selective breeding can be used by farmers to only allow fish with desired characteristics to reproduce
this ensures that the stock of fish is fast growing as these genes get passed on much more frequently

Question 18

how do fish farms affect the environment?

Answer 18

fish may escape and out-compete or interbreed with local species reducing biodiversiry and upsetting the local ecosystem
parasites/pathogens can be introduced into ecosystems by farmed fish
excess feed and waste from fish can cause eutrophication and a reduction in oxygen concentrations in the water (reduced by limiting feed, clearing (vacuuming out) waste and bubbling oxygen through water