New infectious diseases among bees threaten world’s economies

(Source – The Hindu, International Edition – Page No. – 7)

Topic: GS3 – Environment

Context

● Insect pollinators are vital for global agricultural productivity, with over 75% of crops depending on them. ● However, threats like habitat loss, climate change, and emerging diseases are endangering both managed and wild pollinators, especially in regions like India. ● Focused research and conservation measures are essential to protect biodiversity and food security.

 Importance of Pollinators

• Over 75% of food crops and flowering plants depend on insect pollinators like bees, wasps, beetles, flies, moths, and butterflies for successful harvests.
• Declines in pollinator populations due to pesticides, pollution, climate change, habitat loss, and emerging infectious diseases threaten agricultural productivity and economies worldwide.

Role of Wild Bees and Pathogen Spillover

• Wild bees are often more efficient pollinators than managed western honey bees (Apis mellifera).
• Research indicates pathogen spillover between managed honey bees and wild pollinators, with diseases like deformed wing virus and black queen virus threatening the health of wild species.
• A study in Switzerland found that shared habitats increased the viral loads in wild pollinators by up to 10 times.

Pollinator Diversity and Habitat Overlap

• India hosts over 700 bee species, including four indigenous honey bees: Asiatic honey bee, giant rock bee, dwarf honey bee, and stingless bee.
• Habitat loss forces pollinators to share smaller spaces, increasing disease transmission risks between managed and wild species.

Case Study: Thai Sacbrood Virus

• The Thai sacbrood virus outbreak in 1991-1992 devastated 90% of Asiatic honey bee colonies in South India.
• Recent reemergence of the virus highlights the vulnerability of native bee populations to infectious diseases.
• Transmission pathways of the virus remain unknown, posing a significant research gap.

Migration and Competition for Resources

• Managed honey bee migrations disrupt local ecosystems and compete with native pollinators.
• In Maharashtra, diseases linked to introduced honey bees have drastically reduced forest honey production.

Need for Focused Research

• Dedicated studies on emerging diseases like the Thai sacbrood virus can aid in early detection and prevention strategies.
• Monitoring and controlling diseases in managed colonies can minimise spillover risks to wild pollinators, safeguarding biodiversity and agricultural productivity.

Practice Question:  Discuss the significance of pollinators in global agriculture and biodiversity. Highlight the threats they face and suggest measures to address these challenges, with a focus on India’s pollinator diversity. (150 Words /10 marks)