Here, I relate what the journalist said in his article “Pourquoi les pesticides sont bien l’une des causes du déclin des oiseaux”. All quotes, originally in French, were translated by me.
In this article, he defends the responsibility of pesticides, and especially NNIs, in the decline of birds announced by the CNRS and MNHN studies in the previous article (43). This thesis has been criticized, in particular in a Europe 1 column of March 28. He takes up and disputes several allegations.
“Researchers have not shown a causal link with pesticides.
The study in question were not intended “to look for causal links.” To say that pesticides are not responsible for the decline of birds would therefore be a “logical error”.
On the other hand, other studies establish a strong link between pesticides, such as
- the study published in 2014 in Nature showing that the “fall in populations of insectivorous birds was indeed linked to the concentration of neonicotinoid insecticides in the environment (in the Netherlands in this case)”, even at concentrations very low (20 ng / l surface water).
- ONCFS researchers have reportedly documented poisoning of grain-eating birds with seeds coated with NNI.
“Low doses of pesticides have little impact and these inputs weigh three to four times less in bird decline than habitat modification. “
The study on which this statement is based only monitored plots between 2009 and 2011 and the proportion mentioned was calculated by comparing farms with each other, which are “relative data which does not allow us to measure the shared responsibilities of the decline in birds observed for several decades.”
On the contrary, several hundred studies show the deleterious effects on non-target invertebrates. The author takes the example of two meta-studies, one of which concludes that NNIs “are therefore likely to have negative biological and ecological impacts on a large scale and this on a wide range of non-target invertebrates, in terrestrial, aquatic, marine and benthic habitats.”
“It should be noted that in the city, bird populations have also fallen by a third. “
If this implies that the role of pesticides was not decisive, similar decreases having been recorded in the city, that would not prove anything: this decrease could be related to other factors.
“The cause of the disappearance of insects remains a mystery, the authors of this finding have not integrated or studied the effect of pesticides, climate change or other factors. “
The study published in October 2017 by PloS One, observing a 76% decline in flying insects in Germany, “rules out the main possible causes unrelated to agriculture.” (Hallman et al. 2017)