Fisheries Economics

5.2.4. Factor substitution

a) Proliferation of aquatic weeds is a serious menace experienced by farmers growing fish in Thanjavur district. Therefore, they usually give two hand weeding employing human labour. Labour requirement per hectare is 60 human days. Application of 2.5 litre of herbicide – B followed by a hand weeding which requires 25 womendays per hectare could also be done. Wage rate / work day =Rs 15/-. The cost of application of herbicide/ha works out to Rs.30/-. Price of herbicide Rs 106/litre. There is no yield difference between these two practices. Suggest the most economic method of weed control to the fish farmer

For hand weeding = Rs 900 (60 women labourers @ Rs 15)

Herbicide application

Cost of herbicide = 265

Cost of application = 30

Cost of hired labour = 375

                      Total = 670

Reduced cost =Rs 230.00

Format

Gain                 Rs                                     Losses             Rs

Added gain       -                                       added cost         -

Reduced cost 230.00                               reduced return     -

The net gain obtained is Rs 230.00 by introducing herbicide. Hence, we can introduce the change.

b) If the yield of fish increases by 2 % due to the introduction of weed control by herbicide application suggest whether this technique could be adopted or not. The yield obtained earlier was 5 t/ha. Price / kg = Rs 3.

Additional yield realized =  x 5,000   = 100kg

                                             

Gross income realized with hand weeding   = 5,000 x 3 = Rs 15,000

Additional income obtained with herbicide application  = 15,300 (5,100 x3)

                                                                                = 15,300 – 15,000

                                                                                = 300

Gain                           Rs                   Losses                     Rs

Added gain               300                 added cost                 -

Reducedcost            230                 reduced return           -

                        Net gain         =          Rs 530

Since a net gain of Rs 530 is possible with herbicide application, it is recommended for adoption by fish farmers.