European and Belgian citizens have a natural tendency to think that ecological dis-asters always happen far from home. However, recent French, Dutch and even Bel-gian studies suggest that the decline in some types of birds is more than worrying.
In France
A joint study released in March 2018, conducted by the French National Centre for Scientific Research (CNRS) and the Paris Natural History Museum, highlighted the massive disappearance of birds from the French countryside. Where species have not yet disappeared, the study estimates that their numbers have dropped by a third in 15 years. First and foremost, this decline has affected all bird species living in an agricultural habitat: species known as specialists that live mostly in this habitat, and species known as generalists found in all types of habitat, whether agricultural or not.
In Belgium
The findings are equally worrying in that they match the conclusions of the French study. Hence a study that covers 28 years of observation states that on average, bird populations in all species contracted annually by 1% since 1990, furthermore, this has accelerated over the past 10 years. Similar to what has been happening in France, birds living in agricultural habitats are particularly affected.
Which birds are the most affected?
Contrary to what one might think, even previously common birds have been hard hit. Thus the skylark, grey partridge, turtle dove, tree sparrow and even the peewit are among the most affected species.
The turtle dove, or the forest turtle dove in French, is a species that mostly lives in an agricultural environment, contrary to what its name might suggest. Its population is in steep decline both in Wallonia and all European countries, to such a extent that it needed an international safeguarding plan.
What are the accepted or supposed causes?
Climate change is one aggravating factor. Its effects have disrupted migrating birds. Spring now comes earlier. So when the common cuckoo arrives after her migration and looks for nests with recently laid eggs, she only finds nests with young hatch-lings.
The intensification of agricultural practices and methods implemented for this pur-pose are undoubtedly the biggest cause of their decline. The over-conditioning of the soil to increase yields and the use of pesticides has done a lot of harm to bird populations. We could mention the following pesticides, for example :
- Bromadiolone is used as a rodenticide to eradicate voles and as a side-effect kills their predators, including various raptors such as kites, through bio-accumulation ;
- Vermicide used on livestock farms to eliminate endo-parasites, which provide food for some bird species such as wagtails, whinchats and starlings ;
- Neonicotinoids are currently the most poisonous insecticides in use. Dutch and German studies very clearly blame them for the decline in insect populations.
In Germany
The study puts the decline in flying insect populations at 75% to 80% with inevitable consequences for insectivorous birds.
Furthermore, accumulation of all these pesticides in the organism has an effect on avian health by altering reproductive processes and affecting the nervous and en-docrine systems.
Not all is lost, however. Some countries such as the Netherlands, Sweden and the United Kingdom have already implemented policies aimed at counteracting these findings. If we want to reverse the trend, we need to examine our agricultural model. This isn’t just the task of farmers but rather society as a whole, which imposes these practices on farmers with our demands.
Almost three billion birds have disappeared from the USA and Canada over the past 50 years.
This is revealed in a study published in 2019 in the US.