The crossword solution for the term SEASIDE EAGLE is ERN. ERN is a type of eagle found in Europe, Asia, and Africa. It is also known as the White-tailed Sea Eagle and is the largest bird of prey in Europe. The ERN has a wingspan of up to 2.5 meters and is easily recognizable by its white tail and dark brown body. It is a powerful hunter and feeds mainly on fish, but also eats other small animals. The ERN is an important part of the ecosystem and is a protected species in many countries.