110 seals have been shot so far this year to protect the salmon industry, an ITV News investigation has found.
Although they are officially protected, seals can be shot under a special licence.
Salmon farmers and fishermen are allowed to shoot seals attacking their stock.
Campaigners say non-lethal means should be used to deter marine mammals.
Animal rights group Peta has said there is "no justification for shooting beautiful animals" as an ITV News reveals more than 100 seals have been shot to protect salmon farms.
Because shooting is permitted all year round dependent pups are left to starve if their mothers are shot, says charity.
The RSPCA has outlined in detail its policy on the shooting of seals that attack salmon stocks "as an absolute last resort".
The RSPCA is being criticised over its new welfare standards which permit salmon farmers to kill seals that attack fish stocks.