A report on the state of biodiversity in Île-de-France, published on Thursday, warns about the dangers of human activity on the nature of the region. But the study also brings a lot of good news.
We knew the fragile nature, we know it now more vulnerable still in Île-de-France. A report from the Regional Agency for Biodiversity (ARB IdF), published Thursday, June 20, provides a worrying record.
In most cases, proportions of species threatened extinct regionally slightly higher than in adjacent regions, showing influence of metropolis on state of biodiversity, which tends to improve as moves away, read in study that echoes alarming finding recently made by UN experts at global level" AXA8001
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Beyond a risk of extinction of certain animal species, populations "still abundant there is little" have experienced a vertiginous fall, as some species of bat (common pipistrelles and noctules common) or birds, including swallow and house sparrow, which lost 73% of its Parisian workforce between 2004 and 2017.
Butterflies, bats, breeding birds threatened
One responsible for this degradation of fauna and flora: Man. Agricultural practices, strong urbanization, decline of wetlands ... Human activities have endangered many species in just a few years. The "panorama of Ile-de-France biodiversity" also reveals the fact that 31% of the 1,600 species of ferns and flowering plants are threatened, 27% of butterflies, 30% of bats, or 39% of breeding birds.
Cities cover 22% of the territory of the Ile-de-France, "most artificialized" region of the country, notes the ARB IdF. This urban sprawl, even though it has slowed since the mid-2000s, is "one of the main threats" to natural habitats.
But the city also acts "as a filter for the most vulnerable species" to various pollutions (water, air, soil, light, noise ...), replaced by others that adapt better. At the risk of a standardization of ecosystems between Paris, New York or Tokyo.
Agriculture, which occupies 48% of the territory, is also singled out. Pesticides, deep plowing, abandoning grazing ... With a highly developed cereal crop, the "very small" hedge density is a major obstacle to bird breeding. The population of bird species living only in agricultural areas has also "collapsed" by 44% between 2004 and 2017, "even more than at national level (-33%)".
Same worries for insects. If there is no local data concerning them, the Agency is convinced that the region is experiencing the same free fall as that described in Europe by scientists.
Forests, the main "biodiversity reservoirs" in the region covering 24% of the territory, are not spared. They are the cost of the road network that fragments these habitats hosting many mammals, small rodents to deer and wild boar.
After the pessimistic considerations, the study has above all a constructive objective. "The report has been sent to the Ile-de-France region so that its managers can seize the inventory of its territory and develop a relevant strategy," says Julie Collombat-Dubois, director of the France 24 'ARB Idf.
As long as there is life ...
The report is also bringing good news. "We have already seen the positive effects of certain measures on nature. In particular, we have seen the benefits of the ban on pesticides on certain species, "says the environmental manager.
As a result of the successes of nature conservationists, the beaver returned along the Essonne in 2016, 100,000 batrachians are saved each year from the wheels of cars thanks to "toads" (mini-tunnels passing under the roadway), and the flora of sidewalks and interstices exploded thanks to the prohibition of phytosanitary products for the maintenance of roads. The wildcat is regularly observed on the side of the forest of Fontainebleau.
And "the wolf will not fail to make an upcoming appearance in the region, at least in exploration," enthuses the Agency. A perspective that may not be unanimous ...
"It's interesting to see how resilient nature is," concludes Julie Collombat-Dubois. This means that a few things are sometimes enough to change things. It gives a lot of hope. "