Killer whales are one of the most fiercest mammals on earth and are the largest species within the dolphin family (35 varieties). Some killer-whales live mostly on fish, seals, and even larger sea-mammals which they hunt in packs (are therefore often referred to as the wolves of the see).
Also, unusually many sightings have been of Eagles, and many of the rarer species of seabirds as well.
The main reason stated for the increased activity in the fjords is considered to be an abundance of herring close to the shores.