Climate crisis threatens coffee and cocoa pollinating animals – 10/29/2023 – Environment

Some of the world’s main tropical crops, including Brazil’s coffee and cocoa plantations, are at risk of being left without the insects that pollinate their flowers because of the climate crisis. The abundance of these animals, whose presence is essential for the production of a wide variety of fruits, could fall by more than half on a warmer planet, a new study calculates.

According to the research, recently published in the journal Science Advances, the countries whose agricultural productivity is most likely to be affected are, in addition to Brazil, China, India, Indonesia and the Philippines. Fruits such as mango and watermelon are on the list of those that may suffer from a lack of pollinators, alongside cocoa and coffee.

Coordinated by Joseph Millard, from the Natural History Museum in London, the study is also signed by Luísa Carvalheiro, from the Federal University of Goiás, and Felipe Deodato da Silva e Silva, from the Federal Institute of Mato Grosso.

The researchers crossed data on 2,673 locations on the planet and 3,080 species of pollinating insects. Carrying pollen from one flower to another, a “job” performed by animals such as bees, beetles, butterflies and many others, is an essential step for the reproduction of many plants that are not capable of fertilizing themselves.

In the study, the team evaluated what would happen in two different scenarios — temperature increases of 1.5°C and 3°C (in relation to average temperatures before the use of fossil fuels in the world) by the end of this century. They used mathematical models to predict how pollinators would respond to these changes, taking into account the habitats in which they live today. In the tropics, where the heat is already high, these changes tend to be more severe for the functioning of the insect organism.

Although there is still no certainty about how the reduction in the abundance of pollinators can affect a crop — would it be possible, for example, for a much smaller number of individuals to “fill the hole” of those that disappeared? —, the scenario is worrying.

It is possible, for example, that everything appears to be fine with pollination up to a certain threshold of pollinator presence — up to 40% of those that exist today, say — but the loss of another 1% of the remaining ones would be enough to make the mechanism collapse. suddenly.

“And this rapid change can be even more pronounced in the case of plants that depend on pollinators with very specific characteristics”, Luísa Cavalheiro told Sheet. “For example, tomatoes and peppers need to be visited by bees that have the ability to vibrate for pollination to effectively occur. Passion fruit, on the other hand, needs very large bees, and these are the ones that will suffer most from global warming.”

As the loss of pollinators has also been driven by the use of pesticides and loss of natural insect habitats, the problem has already led farmers to resort to manual pollination, carried out by humans. This is the case of plantations such as apples, passion fruit, tomatoes and vanilla.

“However, pollinators do their work for free, while manual pollination requires human labor, which leads to increased costs”, says the researcher.

“Another practice that is increasingly used is the rental of bee boxes, the price of which has been rising more and more. In addition to exchanging a free service for something paid, the number of species managed in this system is small —a european bee Apis mellifera is the most common. But for many crops, these species do not have the right attributes to act as pollinators,” he explains.