Why in news?

The prolonged rainy season in Karnataka over the last three years seems to have adversely impacted the migration of birds. Karnataka is a flyway area for these migratory birds and any disturbance in the transit points will adversely impact the world’s ecosystem.

Highlights:

• India, which is part of Central Asia’s flyway of northern hemisphere birds, is steadily witnessing dwindling of hotspots.
• Experts and birdwatchers across the state confirmed the drastic decline in the number of migratory birds at the hotspots
• The bar-headed goose, one of the most sought-after migratory birds at Magadi lake in Shirahatti taluk of Gadag district, was late this year
• The birds, which start their journey over the Himalayan ranges from Magnolia, refuel themselves in South Peninsular India before heading to South Africa for breeding.
• Every year, 22 varieties of birds migrate between October and November from Mongolia, Australia, Tibet and other areas. This year, there is a stark decline in the numbers.
• Several institutes, including the Bombay Natural History Society (BNHS) and the Wildlife Institute of India, are coming up with satellite tracking and other scientific methods to understand the migration pattern.

What are the reason for the birds late arrival ?

• Copious rains the state received over the last three years could be one of the major reasons
• Overflowing lakes and disturbance in food supply chain due to continued rainfall have meant that 30 per cent-35 per cent of migratory birds, especially wetland and waders, have either postponed their arrival or changed roosting sites.
• Degradation of habitat and human interventions at breeding, staging or wintering sites could be the other deterrents.
• As per the ‘State of Birds’ report published in 2020. the world has lost nearly 72 per cent of bird species due to human interventions.
• Even in Karnataka, which boasted more than 40,000 water bodies two decades ago, now has less than 20,000 lakes.

Which are the major roosting sites?

• Several roosting sites of migratory birds in Karnataka, including the backwaters of Almatti (Bagalkot), Ankasamudra Bird Sanctuary (Ballari), Hadinaru lake (Mysuru), Attiveri Bird Sanctuary (Uttara Kannada), Karanja reservoir (Bidar), Bonal lake (Yadgir), Kodi-Bengre Beach(Udupi) and others.

Which are major migratory birds sighted in Karnataka ?

• Flamingos , gargini, black-tailed godwit, crested & common pochard and others.