In composite fish farming, the surface feeder fish is A. Labeo rohita B. Catla catla C. Cinhina mrigala D. Hilsa
Hint: In composite system, five to six carp fish like Catla , Labeo rohita and Cirrhinus can be grown together in the same pond more economically as they have zero competition for food because Catla feed from surface layer and swims in the upper layer of water and eat zooplankton Labeo is a mid-water feeder and Cirrhinus is bottom-feeder.
Complete answer: In this question, we have asked about surface fedder in composite fish farming. Composite fish culture is a method in which five or six different fish species are grown together in a single system. Fish with different habits are selected because they live in different layers of water and eat different things, so they do not have competition in them and can easily be grown together. So, our first option is Labeo rohita. Labeo is a mid-water feeder. It fed from the middle layer of the water. The next option is Catla catla. As we know, Catla feeds from the surface layer and swims in the upper layer of water and eats zooplankton. Our third option is cinhina mrigala. Cinhina mrigala is the bottom feeder. They eat from the bottom of the composite system. Last option is Hilsa. The Hilsa is filter feeders. They filter feed by grubbing muddy bottoms and eat different types of plankton. As we can see, among them Carla fed from the surface.
So, the correct option is B. Catla catla.
Additional information: Advantages of composite fish culture: (i) we can get a variety in fish yield. (ii) Food is completely and evenly distributed in different varieties of fish. (iii) Fishes do not compete for food.
Note: Catla is a surface and midwater feeder. Adults feed on zooplankton using large gill rakers, but young ones on both zooplankton and phytoplankton. Other surface feeder fish include sardine, herring, bluefin tuna and most sharks.