Guwahati: A study by the Wildlife Institute of India has confirmed the significance of the Northeast Indian region, specifically select sites in Nagaland, as important stop-over sites for Amur Falcons during their autumn migration.
“We believe that prey availability, particularly termites, likely influences stopover site selection by the Amur Falcons in the Naga and adjoining hills,” the study says.
“Morphological examination of the termites resulted in the identity to be the genus Odontotermes. Further based on specific characters, two species: O. feae and O. horni were confirmed to be the termite species in the diet of the Amur Falcons in Northeast India,” the study reveals.
The study, ‘Understanding the Amur Falcon (Falco amurensis), their stop-over sites in Nagaland and their migratory routes for better conservation planning’ was done by R S Kumar and others of the Wildlife Institute of India.
The study, as part of the Amur Falcon Conservation Initiative, helped create mass awareness and garner the support of local Naga people bringing about a change in their attitude towards hunting practices.
The satellite tracking initiative proved effective in producing positive results in conserving Amur Falcons through the engagement of local communities in falcon conservation.
The Amur Falcons arrive in the breeding areas in May-June across years and on average spent 123 days in the region. The Falcons arrive in December-January in non-breeding grounds where they spent on average 70 days. They showed high site fidelity to both their breeding as well as non-breeding grounds.
In autumn, Amur Falcons make a stop-over in Northeast India, arriving between mid-October to early November and spending an average of 18 days.
During spring, Amur Falcons spent the stop-over in Somalia reaching by early to mid-April and stopping over for an average of 17 days. The falcons departed from Somalia in late April-early May, before undertaking non-stop flights over the Arabian Sea.
Long-distance migratory birds spend an exceptional amount of energy during their migratory journey where they travel vast distances every year. One such is the Amur Falcon Falco amurensis known to pass through the Indian subcontinent, specifically through parts of Northeast India during their southbound migration to Southern Africa.
“During the stop-over period, we observed flocks of Amur Falcons feeding primarily on huge swarms of termites in Nagaland and adjoining sites in Assam and Manipur. We identified the termite species to be Odontotermes feae, which largely emerges in the region during the stop-over season,” the study said.
In the Naga hills and adjoining region, the researchers observed prolonged and intense termite swarming throughout the stop-over season supporting huge congregations of Amur Falcon.
The arrival of Amur Falcons in Northeast India during October coincides with the mass emergence of termites in the area. “This is also the time of year when the period of high rainfall (South West Monsoon) from June to September comes to an end and likely triggers termite emergence. Swarming behaviour in termites is generally known to occur after periods of rain and soon after when the weather is warm and the soil is moist,” the study says.
Local people in the region also reported Amur Falcons forage actively on the swarming termite alates during the stop-over period.
“The migratory routes, strategies, and behaviour of Amur Falcons clearly signify their stop-over in Nagaland and other parts of Northeast India is of great significance. The reserves Amur Falcons build up at the stop-over sites in Northeast India prepare them for their onward non-stop migratory flights over the Arabian Sea and thereby determine the overall success of their migration. The number of Amur Falcons seen across Northeast India further highlights the presence of resource-abundant stop-over sites sustaining the falcons for their 15 to 20 days of stay in the region. Our study shows that the arrival of falcons coincides with the mass emergence of termites in the region and therefore the presence of such a large number of falcons actually helps in keeping a check on emerging termites and thereby plays an important ecological role,” Amarjeet Kaur, a research scholar at Wildlife Institute of India who is a part of the study, said.
Interestingly, during the return passage from Africa on their spring migration, Amur Falcons do not stop over in large congregations in Northeast India suggesting the non-availability of prey is likely the reason,” the study found out.
The scale of termite emergence in the region is likely to be immensely high in order to sustain a million Amur Falcons thought to stop over there and for a minimum period of 10 days.
Amarjeet said in light of future climate change events which are likely to influence the phenology of many species, any change in prey (resource) availability and habitat at the stop-over sites can alter the migratory cycle of Amur Falcons.
“Carrying out long-term studies on Amur Falcon’s diet at the stop-over sites, termite species distribution and emergence patterns across stop-over sites become important,” Amarjeet said.
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