Composite Fish Culture - UNSOLVED PRACTICE SET
Chapter: Improvement in Food Resources | Topic: Composite Fish Culture
COMPOSITE FISH CULTURE - UNSOLVED PRACTICE SET
Topic: Composite Fish Culture
Multiple Choice Questions
Q1. Composite fish culture is a system in which:
- Only one type of fish is grown in a pond
- Different species of fish with different food habits are cultured together in the same pond to maximise production
- Fish and poultry are grown together
- Fish are caught from different rivers
Q2. In composite fish culture, surface feeders like Catla feed on:
- Bottom-dwelling organisms
- Zooplankton and phytoplankton at the surface
- Other fish
- Only artificial feed
Q3. Bottom feeders like Mrigal in composite fish culture help by:
- Swimming at the surface
- Consuming food that sinks to the bottom, cleaning the pond and reducing waste
- Eating all the other fish
- Providing oxygen
Q4. The main advantage of composite fish culture over monoculture is:
- It is easier to manage
- It uses all available food niches in the pond, increasing total fish production per hectare
- It requires more water
- It produces only one type of fish
Q5. Which of the following combinations is commonly used in composite fish culture in India?
- Only Rohu
- Catla (surface), Rohu (middle), Mrigal (bottom)
- Only shrimp
- Only exotic fish
Short Answer Questions
Q6. What is composite fish culture? Why is it considered more efficient than growing a single fish species in a pond?
Q7. Name three Indian carp species commonly used in composite fish culture and state their feeding zone (surface, middle, or bottom).
Q8. How does composite fish culture ensure that all the available food in a pond is utilised? Explain with reference to the different feeding habits of Catla, Rohu, and Mrigal.
Q9. A fish farmer grows only Catla in his pond and gets 1,000 kg per hectare. His neighbour practises composite fish culture with Catla, Rohu, and Mrigal and gets 3,000 kg per hectare. Why is there such a big difference in production?
Long Answer Questions
Q10. Explain composite fish culture in detail. Describe the principle behind it (utilising different food niches), the commonly used species (Catla, Rohu, Mrigal, and sometimes grass carp and silver carp), their feeding habits and zones, the advantages (higher yield, better pond utilisation, reduced waste), and the management practices required (stocking density, feeding, water quality, disease control).
Q11. "Composite fish culture is an excellent example of sustainable resource utilisation." Discuss this statement by explaining: how this system mimics natural ecosystems, why it produces more fish per unit area than monoculture, how it reduces the need for expensive artificial feed, the economic benefits for small farmers, and what challenges need to be managed (predators, oxygen levels, disease, proper species ratio).
APPLICATION / ANALYSIS
Q12. Case Study — Fish Pond Comparison:
Two farmers in West Bengal each have a 1-hectare pond:
| Factor | Farmer X (Monoculture) | Farmer Y (Composite Culture) |
|---|---|---|
| Fish species | Only Rohu | Catla + Rohu + Mrigal |
| Stocking density | 5,000 fingerlings | 8,000 fingerlings (mixed) |
| Feed used | Artificial feed only | Minimal artificial feed |
| Total production | 2,000 kg | 4,500 kg |
| Market price | Rs 150/kg | Rs 150/kg (average) |
| Feed cost | Rs 60,000 | Rs 20,000 |
Answer the following:
(a) Calculate the net profit (income minus feed cost) for both farmers. Which system is more profitable? Show all calculations.
(b) Why does Farmer Y achieve more than double the production with less feed? Explain the science behind composite fish culture.
(c) If Farmer X wants to switch to composite culture, what is the ideal ratio of Catla:Rohu:Mrigal he should stock? Why is this ratio important?
Q13. Real-Life Application — Community Fish Pond:
Your village panchayat wants to develop a 2-hectare community pond for fish production to generate income for village development.
The pond has:
- Some aquatic plants at the surface
- Plenty of plankton in the water column
- Muddy bottom with organic matter
- Good water supply from a canal
Village resources:
- 20 families willing to contribute labour
- ₹50,000 initial budget
- A local fishery department officer for guidance
Answer the following:
(a) Which fish species would you recommend stocking, and how many of each? Design a simple stocking plan for the 2-hectare pond.
(b) How would you involve the 20 families in managing the pond throughout the year? Suggest a simple duty rotation system.
(c) After 10 months, if the pond produces 6,000 kg of fish, how much income would be generated at ₹140 per kg? If 30% is kept for next year's seeds and maintenance, how much is available for village development?