Why Is Pollinating Insects are Declining and How Will it Impact Crops?

Over the past 25 years, bee colonies in the Hanumangarh district of Rajasthan, India, have witnessed a significant decline in honey production, dropping from 50-60 kg during the mustard growing season (October to March) to a mere 15 kg.

This decline in honey production is not unique to Hanumangarh but is a concern shared by beekeepers and farmers across several Indian states, including Rajasthan, Uttar Pradesh, Madhya Pradesh, and Haryana.

Various local accounts and regional studies have highlighted the diminishing bee populations and honey production. For instance, a 2022 study in Bengaluru reported a 20 percent decrease in bee abundance, while another study identified giant honeybees as endangered in India.

A recent global study, published in Science Advances, has raised alarm bells by asserting that the decline in pollinators could jeopardize tropical crop production.

Led by researchers from the University College London and the Natural History Museum, the study predicts that the projected risk to crop production in 2050 due to insect pollinator declines will be most severe in tropical regions of sub-Saharan Africa, South America, and Southeast Asia.

In terms of total production, China, India, Indonesia, Brazil, and the Philippines are at the highest risk. Among crops, cocoa is estimated to be the most vulnerable, especially in Africa, followed by mango in India and watermelon in China.

The decline in pollinators is a cause for concern because these insects play a vital role in plant reproduction. Pollinators, including bees and moths, visit flowers to feed on nectar and pollen, facilitating the transfer of pollen from one flower to another, which is crucial for fruit and seed production.

Approximately 75 percent of the world's flowering plants and about 35 percent of its food crops rely on animal pollinators for reproduction, according to the United States Department of Agriculture.

In India, moths have been identified as vital pollinators in the Himalayan ecosystem, with a 2022 study highlighting their role in pollinating 21 plant families in Sikkim and Arunachal Pradesh.

Furthermore, bees alone are critical for pollinating crops across 50 million hectares in India, and their declining populations are already impacting crop yields, leading to potential food insecurity and income loss, especially among small-scale farmers.

Several factors have contributed to the decline in pollinators. Global changes in climate and land use have adversely affected key tropical crops by reducing the number of pollinating insects, particularly during periods of abnormally high temperatures and reduced flowering plant availability.

Habitat destruction, improper land use practices like overgrazing, fertilizers, and monoculture farming have also played a role. India has lost significant forest cover due to urbanization, agricultural expansion, and deforestation, thereby destroying and fragmenting crucial pollinator habitats.

Government initiatives promoting genetically modified (GM) crops and the Green Revolution have incentivized monoculture farming, simplifying biodiversity and reducing the number of pollinators and natural pest control insects. Monoculture environments also lead to increased pest populations, further endangering pollinators due to diseases caused by these pests.

Additionally, the intensification of agriculture through monoculture has heightened reliance on synthetic agrochemicals such as pesticides and fertilizers, which deter bees from visiting crops and disrupt the entire food system.

A 2011 study in India found that the area under pollinator-dependent crops initially increased but declined after 1999, and the relative yield growth rate of these crops slowed after 1993, indicating pollinator limitations.

Environmental pollution, including sewage, landfill leachates, air pollution, and industrial chemicals, has also contributed to the decline in insect pollinators. In summary, addressing the decline in pollinators requires global action to mitigate climate change, slow land use changes, and protect natural habitats, as only these efforts can halt or potentially reverse the decline of these crucial pollinating insects.