Lopao'o Natanielu Mua was responding to reports of dwindling catches by local commercial fishers who blamed illegal competition from foreign vessels.
Lopao'o said Samoa's fisheries management body analysed the claims.
He said environmental conditions and seasonal variations impacting the movement of tuna stocks were likely responsible for the diminished catch.
El Nino climate conditions and escalating climate change are also thought to be factors.
Source:
RNZ