A first compilation of harrier roost counts from India suggests population declines of wintering birds over 30 years

The Indian subcontinent is a major wintering area for many migrant birds from Central Asia and Russia and has experienced unprecedented landscape changes over the last two decades. The effects of these changes on the population of bird communities, especially on raptors, are unknown or poorly assessed. Migrant harriers Circus spp. that require large open grassland, savannahs orsparse scrubland to roost and forage in their wintering quarters, have becomescarce in recent times. The species composition and abundance of harriers athistorically documented roost sites, when monitored across years, can providevaluable information on their demographic status since data from their possible breeding locations in Russia is not readily available. Here, we collate published and unpublished information on various harrier roosts using predefined protocols to assess trends in the counts of harriers in protected and unprotected sitesacross the Indian subcontinent. Harrier counts across all sites, both protectedand unprotected, showed a declining trend over the period 1985-2015. Limited species-specific data from two sites show a significant decline in Western Marsh Harrier Circus aeruginosusbut not in Pallid Harrier C. macrourusand Montagu’sHarrier C. pygargus. These may be early signs of population declines at a continental scale, and we urge the development of more robust systematic ways,along with the current method, to monitor harrier populations. There is a need for improvement of international collaborations with researchers in the breeding areas to conduct studies on long range migrants and to set up a national conservation plan to protects harriers and grasslands.