is less. Fewer frogs, fewer cats, fewer fish, fewer birds. Less snakes. In just 50 years, the abundance of vertebrates on the planet has declined by 69% according to a review of animal populations by WWF and the Zoological Society of London.
The paper analyzes not the number of species, but the evolution of the number of specimens of wild vertebrate species found in the area over time. Sampling a species provides an index of abundance. If fewer specimens are found, its index falls, that is, the population size of this species has decreased. “The global index is generated by calculating the average trend of tens of thousands of terrestrial, marine and freshwater populations around the planet,” the report describes.
There were nearly 32,000 populations of 5,230 different species of amphibians, reptiles, mammals and birds. And the average global trend is very much downward. 69% lower than in 1970. “Now we have a clearer picture than ever before of developments around the world,” explains the analysis. And it’s not flattering. The main causes of the biodiversity crisis are as follows:
- Habitat degradation and loss: Changing land use for urban, infrastructural or agricultural purposes is a major cause of biodiversity loss on the planet. “This is the biggest threat,” concludes this global analysis.
- Overexploitation of species: The calculation is that plants and animals are overexploited at 75%, which is equivalent to “living on 1.75 Earth-sized planets”.
- Pollution: from both sides Air, land, fresh water bodies and the sea.
- Invasive species: The introduction of exotic species that displace and destroy native species is caused by human commercial or recreational activities.
- Climate change: This crisis is triggering “cascading effects” that are shrinking the natural world. “It has not been a dominant factor to date, but if we do not limit global warming, it is likely to become a major cause of biodiversity loss,” it warns.
The slope varies depending on the area of the universe being observed. The global trend describes part of the reality, but leaves out nuances. Fauna deterioration in North America is not the same as in Southeast Asia or Europe. In fact, the worst situation is concentrated precisely in two pockets of exceptional wealth, such as Africa and South America-Caribbean.
All regions of the planet are experiencing some reduction in the number of animals: in Europe and Central Asia this decline is 18%, and in North America 20%; In South America and the Caribbean, the decline is 94% compared to 1970
Nevertheless, all regions of the planet are experiencing a certain decrease in the number of animals. While in Europe and Central Asia the decline in the last 50 years is 18%, and in North America 20%; In South America and the Caribbean, the decline is 94% compared to 1970. For being such a biodiverse and lush area, there is still plenty to do. However, it is much less than it was accumulated just half a century ago.
In Africa, the loss rate is 66%, and in Asia-Pacific – which includes Oceania – 55%. Always compared to the situation assessed five decades ago.
A wreck that threatens “human life”
Biodiversity is “the diversity among living organisms” as defined by the United Nations. “It is necessary for this the function of ecosystems and their services“- adds the Food and Agriculture Organization of the United Nations (FAO).
In other words, good biodiversity enables the provision of the ‘ecosystem services’ that ‘make human life possible’. There are many examples: they provide food and clean water. They also regulate diseases, because they contain viruses and pathogens that can jump to humans – like SARS-Cov-2, which causes COVID-19, allow pollination of crops, normalization of the climate and the soil that is lost. leaps and bounds.
“Despite the economic value of these services amounting to $125 billion, they do not receive adequate attention in policy and regulation,” the FAO decries. And biodiversity is a key part of its functioning.
The International Union for Conservation of Nature develops an index that shows the probability of survival of species classes. Since 1980, all classes have declined – the case of corals is a complete collapse in just 15 years, from 1995 to 2010.
Two faces of the same crisis
This paper argues that humanity is facing a climate crisis and a biodiversity crisis, but the two are “not separate issues”. Global warming is already causing “extremely lethal processes” to the extent that some species, such as the golden toad or the rodent, have even been attributed with total extinction. Melomi rubicola.
The climate crisis, at the same time, is changing the functioning of ecosystems. “Increasing fires, drought-killed trees and insect infestations, drying peatlands and melting tundra permafrost all release more CO2.” Habitats that have so far mitigated the greenhouse effect by absorbing gases are being emitted.
WWF Spain Secretary General Juan Carlos del Olmo confirms that this report indicates that “we can build a future in which both people and nature flourish, but systemic changes are needed in our production and consumption, our technology. use and our economic and financial systems’.
Source: El Diario