concept

Reproductive value

The contribution an individual of a given age can still make to future generations. Calves have low value because most will not survive to breed; an adult female currently raising young has the highest, having already cleared every risk and with many births still ahead. Sensitivity analyses of cetacean population matrix models show that the growth rate depends on adult female survival with a coefficient above 0.8, and on birth rate below 0.1. Which means: the demographic damage of a death is not proportional to the animal's mass but to its reproductive value. A hunt that targets nursing mothers has found precisely the class that inflicts the greatest possible loss.