The Irish Seal Sanctuary has offered a €3,000 reward for information leading to the prosecution of those responsible for the slaughter of 60 grey seals on the Blasket Islands last month.
Forty-four pups and 16 adults from the protected species were either shot or bludgeoned to death on Beginish Island.
The Irish Seal Sanctuary said it was also seeking a meeting with Environment Minister Dick Roche to discuss the possibility of strengthening legislation protecting such species.
Spokesperson Pauline Beades said: "Whoever did this crime should be brought to justice. They don't represent anybody but themselves."