Nucella canaliculata has a robust shell with a strong spire, a short notch to house the siphon, and up to seven whorls.

The whorls are demarcated from each other by deep grooves and are sculpted with many low spiral ridges of approximately even size.

The surface of the shell is matt; small individuals are often orange while larger ones are grayish or pale brown.

It is found on both exposed and sheltered rocks in the intertidal zone and is particularly common in wave-exposed areas of the Olympic Peninsula and near mussel beds.

A toxin is then injected through the hole which causes the barnacle's muscles to relax and the opercular valves to gape, whereupon the dog winkle can easily consume the soft tissues.