"These wild Changewings live on Dragon's Edge. They always seem to have a problem with someone on the island, whether it be a Dragon or a Rider."
―Dragons: Rise of Berk
Race to the Edge
In When Darkness Falls, the Edgewing pack scared and tried to attack the defenseless Night Terrors after the gang caught their leader Smidvarg. Once they released him, the Night Terrors quickly formed the silhouette of a larger dragon and scared the Edgewings off.
Even though the Edgewings are regular red Changewings in Race to the Edge, they are fuchsia with orange and yellow wings in Rise of Berk.
The name "Edgewing" actually refers to any member of a specific group of Changewing, not a subspecies. The same thing is applied to the name Nightwatch.