Abusive and threatening letters have been received by staff at the River Annan Fishery Board after a seal was shot dead by a trained marksman.
Sammy was shot because of concern about fish stocks
The animal - dubbed Sammy the Seal - was killed because of its impact on salmon stocks in the area.
News of the killing has prompted an angry backlash with letters sent to staff at the board.
Manager Nick Chisholm said it was unacceptable that his staff were being put through such distress.
A trained marksman shot and killed the seal last month in the light of the fishery manager's conservation concerns.
Mr Chisholm said it had been carried out after attempts to move the mammal or scare it off had failed.
The move was criticised by the Scottish Sea Life Sanctuary which claimed it was financially motivated.
A spokesman said the effect of the seal was minimal compared to continued fishing of the river.