A spokesperson for the Earth Island Institute says the Solomon Islands government needs to take action on the custom of dolphin culling.
Mark Berman says a dispute over missing funds, promised to people in the village of Fanalei, should be investigated further.
But the people of Fanalei village say they reverted to the traditional practice of hunting dolphins after they were not paid money promised to them by the Earth Island Institute to stop the practice.
There are reports of up to a thousand dolphins being killed this season.
Mr Berman says donors have lost their trust as they don't know where the missing money went.
"Until we find out exactly what happened you know the donors cannot, will not provide what's necessary to continue. You know they did this in good faith to help this community their projects that they need and find substitutes for the killing of dolphins."
A spokesperson for the US-based NGO Earth Island Institute, Mark Berman