Question

A lot of fishes are dying near a sea shore. Describe any two possible causes.

Answer 1

(i) Sewage:
Sewage is the liquid waste from domestic activities. It consists of kitchen wastes, toilet and other household wastewater. Small towns and villages releasing their fluid wastes directly into some nearby large water body.
(ii) Oil Spills:
Oil Spills are the accidental discharges of petroleum in oceans or estuaries. The sources of spills are the overturned oil tankers, offshore oil mining, oil refineries. Oil pollution kills a lot of marine life.
(iii) Industrial Waste:
A large number of industries produce wastewater which contains various types of chemical pollutants. Such wastes are commonly discharged into the rivers.

these are the reasons could lead to lack of dissolved Oxygen in the water resulting in a large number of dead fishes being washed to the shore.