Are rice paddies suboptimal breeding habitat for Sarus Cranes in Uttar Pradesh, India?

The globally threatened Sarus Crane (Grus antigone) has low annual productivity and occurs mostly in landscapes dominated by agriculture; it is therefore vulnerable to extinction caused by human-related disturbance and mortality. The Sarus Crane’s increased use of rice paddies as breeding habitat has fueled concerns that the species is being forced to use suboptimal habitats. To assess the issue, I studied nest-site selection and quantified nest and brood survival of Sarus Cranes in Uttar Pradesh, northern India, during 2000 and 2001 and evaluated differences between natural wetlands and rice paddies. The cranes preferred wetlands as nesting habitat at the levels of both the landscape and individual territory. The success (daily survival rate) of nests closer to roads was lower, suggesting that human-related mortality played a role. The effect of habitat on nest success was equivocal, suggesting that rice fields per se are not suboptimal as nesting sites. This result is unique to this area, suggesting that favorable attitudes of farmers still allow Sarus Cranes to nest in rice paddies. Broods hatching later and those in territories with fewer wetlands had a lower probability of survival. Vegetation changes and disturbance during crop harvesting likely decreased brood survival. Maintaining a patchwork of shallow wetlands in rice-dominated landscapes and ensuring that farmers retain a positive attitude toward the species are crucial for survival of Sarus Crane nests and broods.