As the Earth’s sixth mass extinction event gets into full swing, the planet’s wildlife faces “annihilation”, according to the latest research. It has been found that the rate of decline currently facing the world’s plants and animals is far worse than we have previously thought, and that the focus on species as a whole may not help us in the long run.
The researchers found that around two species of vertebrates go extinct every year, which might not sound that dramatic, but is thought to be 10 to 100 times greater than the natural rate. But they also note how this may be hiding a far more worrying trend in which individual populations are sputtering out of existence as ranges are constricted and divided, which could be equally as damaging.
By looking at the ranges of 26,700 different terrestrial vertebrates, covering around half of all known birds, mammals, amphibians, and reptiles, they found that more than 30 percent of the animals were declining in population size and range. They then analyzed in more detail the populations of 177 mammals as a proxy, and found that while all had lost more than 30 percent of their ranges, a staggering 40 percent of the mammals had lost up to 80 percent of their natural range.
“The mass extinctions have been viewed as the loss of species,” explained Paul Ehrlich, co-author of the study published in the Proceeding of the National Academy of Sciences. “But equally important – or more important – are the loss of the populations that make up those species. Now, why do we care about those populations? Well, for example, we’re losing populations of birds, bats, and insects that control the pests that allow us to remain in high yield agriculture.”
So while individual animals might not be extinct as a species, the researchers are warning that this does not matter if vital populations no longer exist. For example, if the honey bee survived in a small population in Mexico and the species was still clinging on, the agricultural industry in the United States would still be ruined as they lose one of the most important pollinator species locally.
“So it’s important to recognize that [while] losing species is bad and largely irreversible, losing populations and losing individuals from populations is wrecking our life support machinery,” continued Ehrlich.
This piece-meal loss of species from one population to the next is bad news for us, as the health of the planet suffers. Ecosystems are slowly stripped of their components, meaning that wetlands no longer function to purify water, or that the survival of forests that prevent flooding are threatened. The disappearance of populations is also a precursor for the extinction of species, and so more attention should be paid to how an animals range and population is faring.
