ICSE Class 7 Answered

The mining of the deposits of nitrates led to the destruction of the habitat of birds in the Guano Islands. No measures were taken to save their population. This resulted in declining numbers of birds on the islands. Secondly, the catching of anchovies for the purpose of making fish oil further affected the bird population as anchovies were largely eaten by the sea birds. As the number of birds visiting the Guano Islands dropped, the deposits of nitrates began to reduce.