A perch is an old unit of length equal to 5.5 yards, also called a rod or a pole.
Yellow Perch
A perch is a type of fish belonging to the family Percidae.
The perch spawns at the end of April or beginning of May, depositing it upon weeds, or the branches of trees or shrubs that have become immersed in the water; it does not come into condition again until July. The best time for fishing for perch is from September to February; it haunts the neighborhood of heavy deep eddies, camp sheathings, beds of weeds, with sharp streams near, and trees or bushes growing in or overhanging the water. The baits for perch are, minnows, red, marsh, brandling or lob worms and shrimps. The tackle should be fine but strong, as with a fish bait a trout or pike may frequently be hooked. Perch, unlike fish of prey, are gregarious, and in the winter months, when the frosts and floods have destroyed and carried away the beds of weeds, congregate together in the pools and eddies, and are then to be angled for with greatest success from 10 to 4 o'clock, at the edge of the streams forming such eddies.