Parrs

Parrs is the plural form of parr, a term used in ichthyology to describe a juvenile stage of salmonid fish, including Atlantic salmon and various species of trout and other salmonids. During this stage, fish reside in freshwater rivers and streams. Parr are characterized by distinctive vertical markings, or parr marks, along their sides, which help camouflage them and differentiate them from fry and older smolts. The parr stage follows the fry stage and precedes smoltification; its duration is species- and environment-dependent, often lasting several months but sometimes longer in slower-growing populations.

In ecology and fisheries science, the parr stage is important for understanding population dynamics, growth rates, and habitat quality. Parrs feed largely on aquatic invertebrates and small prey, and their survival depends on habitat features such as clean, well-oxygenated water, suitable flow, and the availability of shelter from predators. When conditions trigger smoltification, many of these fish migrate downstream to the ocean, where they may spend one or more years before returning as adults.

Parrs also refers to a surname and, by extension, to place-names and institutions derived from that name. The word is used in English-speaking contexts to describe families with the surname Parrs and, less commonly, as part of geographic names or commemorative titles.