The nesting ground at Rushikulya river mouth, which plays host to lakhs of female olive ridley turtles for annual mass nesting, has undergone severe erosion, fueling apprehension of aquatic animals skipping annual sojourn this time.
“The nesting beach has got severely truncated. Little space is left for turtles’ annual sojourn for mass nesting. The topographical change of the nesting beach has been due to sediment transport of sands from south to north direction. As a result, the beach as per its current topographical status is not favourable for turtles to crawl onto the beach to lay eggs”, said Pravakar Mishra, senior scientist, the Ministry of Earth Science’s National Centre for coastal research.
The place of the confluence has changed due to massive sea erosion. Sea has almost the entire stretch of beach from Puruna Bandha to Nua Podampeta extending up to 1.5 km length. Due to the eroded shape of the beach, the marine animals may not find it congenial to lay eggs this time, Mishra said.
“Usually the direction of wave approach controls the sand transport along the coast. Along Odisha coast, the predominant direction of wave approach is from Southeast direction. As a result of which the alongshore sand movement is predominantly from south to north. Therefore at Rushikulya, the sand spit acts as a natural barrier and traps the longshore sediment and keeps on growing parallel to the shore. Currently, the beaches are starved of sand due to erosion. As the spit grows northward with time, more length of the rookery beach gets affected and eroded”, the senior scientist observed.
The only solution lies in the fact that the spit should be cut open at the original river mouth so that the sediment from the river as well as from the spit will supply to the northern beach making the beach rather stable, he said.
The Gahirmatha rookery in Kendrapara district, widely acclaimed as World’s largest beach of olive turtles, is also undergoing erosion of the nesting beach. But the erosion phenomenon is comparatively on a lesser scale, said, forest officials.
The Olive turtles turn up in millions for mass nesting along the Odisha coast every year anytime between February to March. Gahirmatha beach off Bay of Bengal coast in Kendrapara district is incidentally acclaimed as World’s largest-known nesting ground of these animals. Apart from Gahirmatha, these threatened aquatic animals turn up at Rushikulya river mouth and Devi river mouth for mass nesting, otherwise called arribada
An Olive Ridley usually lays about 120 to 150 eggs from which hatchlings emerge after about 45 to 50 days. But not all eggs remain intact as predators devour it. Besides, eggs are also washed away by sea waves during high tide. The eggs are incubated in the nest and grow, sans mother, to emerge as hatchlings.