Ringed harrier makes Nemmeli seasonal home

Chennai: Earlier this year, Suzhal Arivom, an environmental research and conservation collective, spotted a ringed adult male Montagu’s harrier (Circus pygargus) at Nemmeli in Chennai. Now it’s been confirmed from the ring number that the bird was originally ringed in Rajasthan by the Ashoka Trust for Research in Ecology and the Environment (ATREE) under their Harrier Watch programme in 2019.“We ringed it as a juvenile in its first year,” says Arjun Kannan, researcher at ATREE. “And there might be other such birds as well at Nemmeli as they are communal roosters.”The birds migrate from Kazakhstan to India, first to Rajasthan and later southwards as the season progresses, when the western Indian grasslands become dry during winter. Afterwards, they fly back to Kazakhstan directly along the Central Asian Flyway (CAF).“After more than a week of observation, the ringed male bird was found to engage in the full range of wintering behaviours that the site evidently supports; perching on open ground and low vegetation in the seasonal grassland and actively hunting over the grassland-wetland mosaic, a habitat type that falls under India’s threatened Open Natural Ecosystems (ONEs),” says Deepak V from Suzhal Arivom. “Roosting at the site, it was seen with an adult female Montagu’s Harrier, an apparent pair.”It shows that the Nemmeli coastal wetland complex is not just an incidental flyover or one-day stopover for this species, says Deepak. “It is supporting the complete suite of behaviours that define a functional wintering ground.”They are known to come back to the same wintering sites every year, says Arjun. “There might be predictable resources at Nemmeli for them to forage in. If something happens to that site, they might be pushed to other suboptimal habitats where they might not have enough experience to be able to forage well.”Nemmeli is known for a mix of grassy and wetland habitats, ideal for harriers. “The Nemmeli coastal grassland-wetland complex supports pallid harrier, western marsh harrier, eastern marsh harrier, pied harrier, as well as peregrine falcon, red-necked falcon, Eurasian kestrel, osprey, fish eagles and spotted eagles. It’s significant as a diverse raptor wintering habitat,” says Deepak.Harriers have been established as a grassland-dependent species group that has shown documented declines of more than 30 years across India due to grassland loss, as documented by ATREE’s published research. “We seek the recognition of the Nemmeli seasonal grassland coastal wetland complex as a documented wintering site for long-distance migrant raptors, in any habitat-mapping or site-prioritization work undertaken under the Tamil Nadu Raptor Research Foundation,” says Deepak. “Guidance from the Advanced Institute for Wildlife Conservation (AIWC) on the appropriate process by which a site such as Nemmeli can be brought to the attention of the Tamil Nadu forest department for habitat assessment, with a view to influencing future land-use and conservation decisions.” The Mamallan freshwater reservoir project at Nemmeli, he says, is a threat and will lead to destruction of this thriving ecosystem.