BHUBANESWAR: This year, an air of uncertainty hangs over the arrival of Olive Ridley sea turtles along the Odisha coast. With nesting grounds not available yet, wildlife experts are apprehensive about mass nesting (arribada) occurring anytime soon. Gahirmatha under Bhitarkanika Wildlife Sanctuary and Rushikulya river mouth are the two major rookeries apart from the Devi river mouth where sporadic nesting takes place. However, this year, the beach profile is such that mass nesting may not take place soon at the sites.