The Earth is running out of bumblebees and that is much more serious than it seems

The old resource to explain sexual reproduction, that of the little bee and the flower, has a solid theoretical basis.

Pollination, which is what bees do on flowers, is one of the most effective strategies for plants to perpetuate themselves.

Or had been until now.

But the progressive decline of many of the pollinating insect species may endanger this successful evolutionary strategy.

"Those of us who work on this have been detecting for some time that in previous studies we found many more species and that, in this century, we have found fewer and fewer," explains Concepción Ornosa, entomologist and director of the Department of Biodiversity, Ecology and Evolution at the Complutense University from Madrid.

"In the United States they began to study it and discovered that, between 2008 and 2013, wild bees had decreased by 23% and that's where all the alarms went off: the disappearance of 23% of the insects that pollinate crops is very serious."

More information

The secret of pollination is found in the body of bees

The investigations carried out warn both about the disappearance of species and about the decrease of individuals.

Ornosa recalls that in 2017 a study was carried out on flying insects in protected areas in Germany "and it was discovered that, in relation to the previous 20 years, up to 75% of the biomass had disappeared."

Biomass is the number of living organisms in an area at a given time.

"The study was mostly about flying insects, but most pollinating insects are flying," she adds.

Pollination is the transfer of pollen to the female part of a flower from its male part.

The result is the fertilization of the plant.

The new ovule contains both the male and female genetic makeup and will give rise to a new generation of the plant.

As the flowers cannot move from the place where they are, they need an agent that transports that pollen.

They can be the wind or the water, but in most cases pollination is carried out by animals, especially insects.

“Within insects, the best pollinators are bees and, among them, the most effective are bumblebees because they have a lot of hair.

When they feed on a flower, part of the pollen sticks to that hair and falls on the next flowers they visit”, explains the entomologist.

Precisely to these species of bees, the bumblebees, is dedicated a wonderful popularization book written by one of the world's leading experts, the British Dave Goulson, and recently published in Spain:

.

In his book, Goulson warns of the disappearance of many species of bumblebees in the United Kingdom and the rest of the world and how serious this fact is for our own survival.

Any event that endangers pollination is no joke.

According to the Food and Agriculture Organization of the United Nations (FAO), about 35% of invertebrate pollinators, especially bees and butterflies, and about 17% of vertebrates, such as bats, are in danger of extinction. .

And when the FAO and many other international institutions warn of this danger, they are literally referring to the risk to world food production.

According to the organization, more than 75% of the world's food crops depend in some form on pollination.

The situation is so serious that many countries have been designing regulations for a few years to try to reverse the situation.

The European Union launched the

in 2018 and in Spain the National Strategy for the Conservation of Pollinators was approved in 2020.

The annual benefits of global crops that depend on pollinators are between 235,000 million and 577,000 million euros and, also according to the FAO, their amount is increasing.

According to the Spanish strategy, in our country it is estimated that 70% of crops for direct human consumption depend in some way on pollination by insects.

“The state of pollinating insects, and in particular bumblebees, is dramatic.

In 2018, we published a study we did in the Spanish Pyrenees in which we compared the data we had from previous research with the populations we found.

Of the 36 species that had been described, we only found 27. And, in addition, the ones we found were located at higher altitudes”, says Concepción Ornosa.

The causes of this situation are varied: changes in land use, the presence of fertilizers in the soil, the introduction of invasive species, global warming... It is a series of modifications in ecosystems that, together, have become a bomb.

Óscar Aguado, co-author of the

assures that you walk through the countryside “and you no longer see natural vegetation.

We need green corridors with native flowers, both in the countryside and in the cities”.

Insects need flowers because without them they don't have food, and if they don't visit flowers to feed, pollination doesn't take place.

Some of the solutions may be difficult to implement, but others are not: “One very easy thing that can be done is that now, as soon as what we call weeds come out, they are uprooted from roads, gardens, parks… and that is a wonderful habitat for pollinating insects," explains Ornosa, who adds: "It would be much more efficient to wait until they dry up to pull them out and thus let the insects feed on them.

Or prune the trees and bushes in the fall when they no longer have flowers.”

The goal is to save pollinating insects because, as the last sentence of Dave Goulson's book says: "Maybe if we learn to save a bee today, we can save the world tomorrow."

You can follow

50% off

Subscribe to continue reading

read without limits

Keep reading

I'm already a subscriber