Question

A crane had DDT level as $5$ ppm in its body. What would happen to the population of such birds? Explain giving reasons.

Answer 1

Biomagnification

1. Biomagnification is a phenomenon by which certain pollutants go on to accumulate in tissues in increasing concentrations along the food chain.
2. The toxicant increases in concentration at successive trophic levels.

The effects on the population of birds having high levels of DDT are as follows:

1. DDT is a pollutant that is not metabolized or excreted by the body and gets accumulated at successive trophic levels.
2. A crane having a DDT level as $5$ ppm in its body cannot metabolize calcium properly.
3. It causes thinning and weakening of the eggshells which cause premature breaking of eggs.
4. This ultimately leads to a decline in the population of the cranes.