Federal-funded efforts to contain the fourth big outbreak of crown-of-thorns starfish on the Great Barrier Reef are "sporadic" and a "serious case of negligence" that will likely fail, according to a leading scientist who reviewed the program.

Udo Engelhardt, director of consultancy Reefcare International, claims his analyses of the crown-of-thorns (COTS) controls for 2013-15 demonstrated the "widespread and consistent failure" to protect coral cover.

A fourth major crown of thorn starfish has been underway since 2009 with little sign that culling is having a significant effect, scientists say.

This information was provided to the Reef & Rainforest Research Centre, which oversees the program contracted to the Association of Marine Park Tourism Operators (AMPTO). It is also under the oversight of the Great Barrier Reef Marine Park Authority.

But almost two years on, neither the report not photographs had been made public "despite the fact that both components were paid for using government funds", Dr Engelhardt said.