Officials in Trinidad and Tobago have expressed regret over the crushing of thousands of leatherback turtle eggs and hatchlings.
They said bulldozers had been used to move waterlogged sand from key nesting areas.
They insisted the work was necessary to redirect a river that was eroding the beach and threatening a hotel used by tourists to watch the turtles.
Environmentalists say workers botched the job and destroyed some 20,000 eggs.
"We truly regret the slaughter of these magnificent sea creatures," Shamshad Mohammed, drainage director for Trinidad and Tobago's Environment Water Resources Ministry, said.
The Turtle Village Trust said the bulldozers were sent to the area of the Grand Riviere beach that was considered as the best place to carry out the drainage work in order to save the majority of the remaining eggs.
Sherwin Reyz of the Grande Riviere Environmental Organisation said on Tuesday that vultures and stray dogs had eaten many of the hatchlings whose shells had been crushed by the heavy machinery.
"They had a very good meal. I was near tears," he said.
Leatherbacks return to lay their eggs on the beach where they were born and Trinidad's northern coastline has some of the world's densest leatherback turtle nesting areas.
The mile-long stretch of beach is regarded as a leading nesting sites for the biggest of all sea turtles. Some 3,500 females deposit an estimated 200,000 eggs a year on the Grand Riviere.