A new approach to deciding which areas get selected for protection can save almost twice as many mammals from extinction globally, a study has found, with more than half of the most crucial habitat located in just seven countries.

Habitat protection has traditionally been determined in part based on species range and richness – keeping a certain percentage of a species protected in order to boost its chances of survival.

However, in a study published in One Earth, scientists from The Nature Conservancy (TNC), IIASA, and nine universities and institutions globally, found that by instead focusing on population-level information, such as the growth rates and habitat needs of individual populations of a species, conservation can be made far more effective.

“The global extinction of a species begins locally, occurring one population at a time, and individual populations can be more or less resilient depending on regional factors like land use or management intensity. We need a prioritisation model that reflects those core tenets of ecology,” lead author Nicholas Wolff, director of climate science at TNC, said in a statement.

Linking more than 70,000 unique global population maps using software called Zonation, the study found that the top 10% of identified priority habitat using the population-based approach supported the viability of 84% more populations than using the traditional prioritisation method.

What’s more, while that top priority habitat was spread across more than 143 countries, more than half of it was located in one of only seven countries – Australia, Brazil, China, Indonesia, Madagascar, Mexico, and Papua New Guinea.

As much as 80% of that habitat – 7.3 million square kilometres, similar to the size of Australia – is currently not protected, according to the study, and while 20% is, less than 8% is under strict protection.

Narrowing down further, of the 462,000 sq. km with the very highest value – providing a 75% probability that over 90% of the species there would survive for 1,000 years – some 306,000 sq. km currently have no protected status.

PUTTING IT TO USE

The study comes as most nations worldwide are in the process of drawing up their National Biodiversity Strategies and Action Plans (NBSAPs) to outline how they intend to meet their shares of the Global Biodiversity Framework’s 30×30 target.

As well, an increasing amount of corporations are developing so-called ‘nature positive’ strategies to be aligned with incoming regulations or consumer expectations, while a number of efforts are ongoing to design methodologies for the emerging biodiversity credit market.

If broadly recognised, the study could have a significant impact on all of those processes.

“One strength of the Zonation analysis producing a global rank order of sites rather than a portfolio of places is that it is amenable to supporting decisions at different scales and particularly within different geopolitical units,” the study said.

“For example, if the prioritisation were restricted to a single region or country, then the results would still give a rank order of priority within that region.”

However, the authors stressed that their findings would be optimal if implemented on a global basis, which would be challenging to achieve politically.

Brunei and Liberia, for example, had over 90% of their territory ranked as top priority, and it would be “unreasonable” to expect all of that to be protected.

“Instead, our results can inform where [protected area] target gaps might be filled and prioritise sustainable land use practices that could meet development and biodiversity goals,” the study said.

AT RISK

As part of modelling done for the study, the top priority habitats were also compared with areas under habitat conversion threat, showing that Australia and Russia, in particular, had a big overlap with more than 400,000 sq. km each falling in both categories.

South Africa, Bolivia, Peru, Argentina, Somalia, and Brazil all had more than 100,000 sq. km each that fell in both categories.

“We also emphasise that our results are not a conservation plan. We do not consider what specific protection actions are required to achieve conservation outcomes in any place, only what the impact of doing so could be,” the study said.

“We assume that, in any country, the loss of habitat can be prevented through multiple mechanisms. We also recognise that mammals represent only a component of threatened biodiversity in need of conservation.”

Additionally, while habitat loss is the main global driver for species extinction, there are other factors as well that were not taken into consideration for the study, such as invasive species, climate change, and pollution.

Even so, the study was carried out specifically to inform priorities for The Nature Conservancy, both in its own terrestrial conservation work as well as in its engagement with the sectors responsible for habitat loss in a location.

“There is a wide range of government and non-government conservation actors around the world who either explicitly or implicitly seek to link habitat protection with reducing species extinction risk,” said the study.

“Although only reflective of threatened mammals, the approach described here allows a more direct and quantifiable linkage between conservation action and extinction risk than what has been possible previously at a global scale.”

By Stian Reklev –stian@carbon-pulse.com

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