The physiological reproductive capacity of an organism or population, i.e. its potential ability to produce viable offspring.
Not to be confused with fertility.
Confusing language difference:
Please note that "fecundity" corresponds to "fertilité" in French and "fertilidad" in Spanish whereas the French word "fécondité" and the Spanish word "fecundidad" mean "fertility".
Source: GreenFacts
Español: Fertilidad
Français: Fertilité