Habitat For Mammals Projected To Shrink Globally
Despite the fact that biodiversity and ecosystem services are widely accepted prerequisites for human survival and a crucial resource for human societies in many ways, human pressure remains the main driver of modern biodiversity loss. The two key human drivers of biodiversity loss are land use and climate change.
Obviously, efforts towards sustainability and even biodiversity protection specifically are not novel, with initiatives for halting biodiversity loss having been on the international agenda for more than 25 years. As evidence shows, they are, however, simply insufficient. After all, if the trend continues, the rates of species losses and extinctions are expected to equal that of the five mass-extinction events.
In this study, a group of researchers representing science institutions in Italy, the U.K., and Austria, teamed up to model potential reductions in habitats that are home to a wide range of mammals. The InSiGHTS framework was used to analyze the impacts land-use and climate change may have on future habitat for nearly three thousand terrestrial mammals under five contrasting global action scenarios. These five scenarios were defined in previous research, and include:
- Taking the green road — In this scenario, the world shifts gradually but consistently toward a more sustainable path, focusing on development that respects perceived environmental boundaries. The emphasis on economic growth shifts toward a broader emphasis on human well-being. Inequality is reduced both across and within countries, whereas consumption is oriented toward low material growth and lower resource and energy intensity.
- Middle of the Road — The world follows a path in which social, economic, and technological trends do not shift markedly from historical patterns. Development and income growth proceeds unevenly, with some countries making relatively good progress and others falling short of expectations. Slow progress is made in achieving sustainable development goals. Environmental systems experience degradation, although the intensity of resource and energy use declines.
- A Rocky Road — Driven by resurgent nationalism, concerns about competitiveness and security, countries increasingly focus on domestic issues. Policies shift to become increasingly oriented toward national and regional security issues. Countries focus on achieving energy and food security goals within their own regions at the expense of broader-based development. Investments in education and technological development decline. Economic development is slow, consumption is material-intensive, and inequalities persist or worsen over time.
- A Road Divided — Here, high inequalities and stratification across and within countries is brought on by unequal investments and increasing disparities. Over time, a gap widens between an internationally-connected society that contributes to knowledge- and capital-intensive sectors, and many separate lower-income, poorly educated societies that work in a labor-intensive, low-tech economies. Social cohesion degrades and renders conflicts common. Environmental policies focus on local issues around middle and high-income areas.
- Taking the highway — In the final scenario, competitive markets, innovation, and participatory societies are poised to yield rapid technological progress as the means to achieve sustainable development. There are strong investments in health, education, and institutions to enhance human and social capital. Exploitation of abundant fossil resources is used as a tool to advance economic and social development, resulting in widespread resource- and energy-intensive lifestyles around the world. Local environmental problems like air pollution are successfully managed and there is faith in the ability to effectively manage social and ecological systems, too.
The results of the researchers’ analyses are worrying, to say the least. All scenarios led to declined mammal habitats, ranging from 5 to 16%, and up to 25% regionally. Terrestrial mammals of Africa and South America live in the two regions suspected to be at the highest risk for severe habitat reduction. In terms of specific species, the habitats of African insectivores, primates, Australian carnivorous marsupials and marsupial moles, and South American opossums declined the most throughout the modeled period between 2015 and 2050.
The researchers also looked into the direct effects of land-use change and climate change on habitat availability. Here, it is noteworthy that climate change was found to be the likely main driver of habitat loss. However, the study authors do highlight that projections of land use and climate change are highly uncertain, and specific figures should not be taken at face value. If the used climate-envelope model assumptions hold true, though, the analysis could be able to measure climatically driven habitat loss accurately. On the other hand, the same cannot be said about range expansion gains caused by climate change, that could actually offset the habitats available to the animals to some extent.
We’re surely at a point of time where the combination of dire current extinction rates and future predictions are so abundant, that making direct and proactive decisions is crucial. The researchers conclude that strategies for sustainable development that are more aggressive than the first scenario might be needed to bend the curve of biodiversity loss when it comes to terrestrial mammals. Animal advocates concerned with the well-being of wild animals are encouraged to call for a global shift toward sustainability, extra emphasis on addressing land-use change, and taking more local/regional action aimed at helping endemic species track climate change.