KINGSTON, Jamaica — A Trinidad and Tobago conservation group called Tuesday for a prompt investigation into how government work crews crushed leatherback turtle eggs and hatchlings on a remote beach that experts say is the globe’s densest nesting site for the endangered marine species.

Witnesses in Trinidad’s tiny town of Grand Riviere said they saw thousands of leatherback eggs crushed by heavy machinery over the weekend as workers redirected a shifting river that was eroding the nesting sites and threatening a hotel where tourists stay to catch a glimpse of a tiny leatherback hatchling or a massive adult, which can reach nearly 8 feet long.

The Papa Bois Conservation group said the government allowed the crew to operate a bulldozer and an excavator ‘‘without any qualified supervision’’ on the ecologically sensitive Grand Riviere beach, where female leatherbacks nest.

‘‘It is important to investigate how this was allowed to happen, and to find a solution so this won’t reoccur,’’ the group said in a statement posted Tuesday to its Facebook page.

The narrow Grand Riviere beach in northern Trinidad is noted for the nesting site, and residents depend on ecotourism for their livelihoods. Scientists say that Trinidad hosts what is likely the second-largest leatherback nesting colony in the world.

Marc de Verteuil, of the Papa Bois Conservation organization, said that because of an unusually long rainy season the meandering Grande Riviere River had eroded a lot of the nesting areas before the weekend, but that government crews made a bad situation far worse.