Imagine immortal elephants. With a calving interval of c. 4 years, females produce 25% of their number each year. Half the babies are females, so the growth rate is 12.5%. Elephants are merely long-lived, but this is mathematically close to immortal. Some females are too young or old to breed, so half this, or c. 6% growth rate seems about right, and is. This rough calculation tells us that if we care for elephants, their numbers can double in just over a decade. That quickly becomes a lot of biomass, and it comes in large packets. Conversely, killing more than one in 15 every year will shrink their numbers to extinction. Elephants are a huge conservation problem because both scenarios apply, and they are inextricably connected. This issue of Oryx provides insights into those connections.
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