Sailgull

A sailgull is, in most circumstances, inconsequentially different from a normal seagull. Where they differ is in the sailgull's increased speed, stupidity, and sharpness, as well as their smaller size.

Such birds poorly perceive the white sails of ships against the white of clouds and the pale blue of the sky. Because of this, they are known to occasionally, and entirely unintentionally, tear through sails in flocks of dozens at a time, with their small, streamlined bodies and pointed beaks ripping through the tough canvas with relative ease.

Sailors who journey out onto open ocean will often dye their sails or paint designs on them in order to avoid devastating collisions with sailgulls.