Tropical crops at risk from pollinator loss due to climate change, shift in land use, finds study

Number of insects that pollinate tropical plants declined by 61%

By Madhumita Paul
Published: Sunday 15 October 2023
Photo: iStock

Tropical crops like coffee, cocoa, watermelon and mango, face a potential crisis due to the loss of insect pollinators, according to a new study led by researchers from the University College London and the Natural History Museum.

Altered climate and change in land-use have reduced the number of insects pollinating key tropical crops, the study found.

The main factors driving this decline were identified to be destruction of habitat, improper land-use such as grazing, fertilisers and crop monoculture of farming, along with high pesticide use, it showed.

Using a dataset containing 2,673 sites and 3,080 insect pollinator species, the researchers showed that the combined pressures of climate change and agricultural activities have led to large reductions in insect pollinators.

In this study, the researchers looked at which pollination-dependent crops were most at threat till 2050. The pollinator loss problem is bigger in the tropics, a region less studied, the authors of the report noted. 

The study also found that the number of insects that pollinate those plants declined by 61 per cent.

The highest risk to crop production from pollinator losses will be in the tropical regions of sub-Saharan Africa, South America and Southeast Asia, the researchers projected.

In terms of total production potentially at risk, China, India, Indonesia, Brazil and the Philippines emerged as being most at risk, according to the report.

Among crops, cocoa was estimated to be at the highest risk, by a large margin, especially in Africa, followed by mango, particularly in India, and watermelon in China.

The increased production risk due to loss of pollinators could lead to increased income insecurity for some of the most vulnerable people globally and their reduction could cause increased income insecurity for millions of small-scale farmers in these regions.

Three-fourths of the world’s flowering plants and about 35 per cent of the world’s food crops depended on animal pollinators to reproduce, according to the United States Department of Agriculture.

"Pollinators visit flowers in their search for food (nectar and pollen). During a flower visit, a pollinator may accidentally brush against the flower’s reproductive parts, unknowingly depositing pollen from flower to flower. The plant uses the pollen to produce a fruit or seed," the department noted in a blog. 

The study findings underscored the urgent need to take global action to mitigate climate change, alongside efforts to slow down land use changes and protect natural habitats to avoid harming insect pollinators.

The study was published in the journal Science Advances.

Subscribe to Daily Newsletter :

Comments are moderated and will be published only after the site moderator’s approval. Please use a genuine email ID and provide your name. Selected comments may also be used in the ‘Letters’ section of the Down To Earth print edition.