Bees are in danger: many species are no longer even counted.

Bees are dying out, but perhaps even more worrying is the scarcity of data on many species, which are no longer even reported or surveyed. A shocking study by the Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), the Argentine CNR, shows how the decline of bees has been dizzying since the 1990s. Unfortunately without signs of abating.

We are used to thinking of bees only as honey-producing insects, living in the infamous beehives where one of Mother Nature's most impressive organizations exists. But in reality there are more than 20,000 species of wild bees, all pollinators and therefore essential for the reproduction of hundreds of thousands of plant species, as well as fundamental for the productivity of about 85% of crops.

Yet man seems to have no interest in them and therefore in his own survival. These extraordinary insects, in fact, are threatened by various causes, many of which are anthropogenic.

Among the main ones:

• Replacing natural areas or heterogeneous landscapes with intensively cultivated agricultural areas with a massive use of agrochemicals which deeply affect the survival chances of wild species;
• Intentional and unintentional introduction of invasive alien species , through international trade, which advance to the detriment of native flora and fauna, with negative consequences also in those areas that they intend to preserve;
• Global climate change which, by altering the seasonality, affects the harmony that the populations of natural insects have established in the course of evolution with plants.

In all this there is, in fact, no global monitoring and many species of bees are no longer registered (or perhaps never were). We do not know, therefore, where they are, but one fact is certain: their global number is down since the 1990s .

To avoid the problems generated by insufficient data, especially in certain years, and by the disparity in the number of observations recorded for different periods, the researchers grouped the records into seven large time intervals (1946-1955; 1956.1965; 1966-1975; 1976 -1960) 1985; 1986-1995, 1996-2005 and 2006-2015) and used statistical tools to obtain large averages.

The distribution of the records is not homogeneous for the different regions of the world (50% of the data comes from observations made only in the United States) and in the places where there is more data, therefore, the declining trend of bee species is seen more clearly. But there are no places in the world where the curve is flat , i.e. positive, so the trend appears to be a global phenomenon .

Very worrying also for an aspect that is not always highlighted: not all species of bees can pollinate any plant. Thus the decline of some species may not be compensated for by others.

“Although most bees can pollinate almost any crop or plant, this is not always the case - explains Zattara - There are plants that can only be pollinated by some species of bees. In this sense, biodiversity works like a mattress , because even if you don't know which insect is helping you to increase the productivity of a crop, it still helps you. With the decline of biodiversity, the range of options is also reduced ”.

A study certainly not definitive, due to lack of data and their inhomogeneity, but sadly in line with other alarms that scientists have been launching for decades. Often in the void

Source: greenme