Observation

The performance of the candidates was average in this question.
In part (a), majority of the candidates gave the definition of predation instead of cannibalism. However, some of them mentioned two ways by which cannibalism could be reduced in fish ponds.
In part (b), majority of the candidates stated the advantages of sorting in fish production.
In part (c), majority of the candidates could name five sources of water for fish farming.
In part (d), majority of the candidates could not define the terms latency period and gravid fish as used in fish breeding.
In part (e), majority of the candidates mentioned important water parameters that should be maintained during the artificial breeding of fish.
The expected answers include:
(a)(i) It is the phenomenon whereby fishes mainly carnivorous of the same species prey (feed) on one another due to differences in their sizes.
(ii) - Timely sorting / grading
   - Feeding fish stock adequately / sufficient quantity / timely
  - Preventing overcrowding in ponds
   - Stocking fishes of similar / uniform sizes

(b) -           It reduces cannibalism
-           It enhances feed management
-           It improves fish yield
-           It improves survival rate of fish
-           It enables farmers to have accurate estimate of number of fish in the pond
-           Gives opportunity to remove stunted / fish jumpers
-           Enables the fisher to observe the well – being of fish / disease / injured

(c)  -           Spring water
-           Bore hole / well water
-           Tap water
-           Rain water
-           Rivers
-           Streams
-           Lakes
-           Reservoir

(d) (i)  It is the period between the time the gravid fish is induced with hormone and the time the eggs are ready for stripping / ovulated

(ii) It is a female that is carrying a lot of mature eggs

(e) -   Dissolved oxygen
-     Temperature
-    pH
-    Turbidity or transparency