24 October 2023

In protected areas, the loss of biodiversity among vertebrates is reduced by five times

L'attività umana ha accelerato il tasso di estinzione naturale dei vertebrati di 22 volte. Foto: Pxhere CC0 Public Domain Free for personal and commercial use No attribution required Learn more

Study from the US analyzed trends in vertebrate populations by measuring the effectiveness of land protection policies

by Matteo Cavallito


Protecting large tracts of land can help stem biodiversity loss, with remarkable results for vertebrates such as amphibians, reptiles, mammals and birds. This is reported in a study conducted by the Smithsonian Environmental Research Center (SERC) and Conservation International.

The research, published in the journal Nature, recalls how human activity has accelerated the natural extinction rate of vertebrates by 22 times. A phenomenon capable of destabilizing food webs by jeopardizing fundamental services such as pollination, availability of a healthy diet and disease control.

In unprotected areas, vertebrate populations halve in 40 years

The researchers, led by Justin Nowakowski, SERC biologist and lead author of the study, examined trends over time in 2,239 populations both inside and outside protected areas on every continent on the Planet with the exception of Antarctica.

On average, vertebrates declined by 0.4 percent per year inside protected areas, almost five times slower than specimens living outside them (1.8 percent per year).

At these rates, the researchers note, populations outside protected areas could see their numbers halved in just 40 years. By contrast, the authors continue, protected areas would take about 170 years to meet the same fate.

Twin crises: climate change and biodiversity loss

According to Luke Frishkoff, co-author and assistant professor of biology at the University of Texas at Arlington, quoted in a memo released by SERC, land protection policies “buy us much-needed time to figure out how to reverse the biodiversity crisis” The issue has been in the spotlight for years. Not least because of its economic fallout.

Some observers, in fact, have begun to refer to climate change and biodiversity loss as “twin crises facing the global financial system.”

A recent survey commissioned by the British government and known as “The Dasgupta review,” in particular, pointed out that “our economic system is dependent on biodiversity.” For some time, the survey further notes, governments have recognized how the dual emergencies related to climate and species diversity pose “an existential threat to nature, people, prosperity and security.” Protection policies and investment choices in line with them, consequently, become crucial to averting environmental damage and financial losses.

Climate change is exacerbating the problem

According to the authors, some classes of vertebrates have benefited most from the effects of protection. Amphibians and birds, which under normal circumstances face the greatest threats outdoors, would have gained the most from limiting human impact.

However, some phenomena such as agricultural conversion of nearby land would have resulted in diminishing benefits, and climate change are exacerbating the problem.

Finally, a word of warning: to function well, protected areas need a stable and effective government. “Nations with effective governments often see better enforcement of environmental laws,” the statement points out. “Corruption-free governments are also less likely to misappropriate conservation money—and are therefore more likely to get international conservation money in the first place.”