In a 10 km² forest fragment, researchers recorded 120 individuals of the Bengal florican. They estimated that 30% are subadults and 10% are immigrants. If the average reproductive output per adult per year is 2.5 eggs, and the survival rate to adulthood is 40%, estimate the net increase in the adult population per year.

Step-by-step solution

1. Calculate number of adults: 120 – 30% of 120 (36) – 10% of 120 (12) = 72 adults.
2. Compute eggs laid per year: 72 adults × 2.5 eggs = 180 eggs.
3. Determine number of offspring surviving to adulthood: 180 × 40% = 72.
4. Subtract original adult population from survivors: 72 – 72 = 0.
5. Thus the net increase in adult population per year is 0.

Concept tested: Population dynamics and net growth

Published 20 September 2026 · How this solution was prepared and checked