Perch

Perches Temporal range: Pliocene–recent PreꞒ Ꞓ O S D C P T J K Pg N ↓ [1]
Yellow perch (Perca flavescens)
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Order:	Perciformes
Family:	Percidae
Subfamily:	Percinae Rafinesque, 1815
Genus:	Perca Linnaeus, 1758
Type species
Perca fluviatilis Linnaeus, 1758
Species
P. flavescens Mitchill, 1814 (yellow perch) P. fluviatilis Linnaeus, 1758 (European perch) P. schrenkii Kessler, 1874 (Balkhash perch)

Perch is a common name for freshwater fish from the genus Perca, which belongs to the family Percidae of the large order Perciformes. The name comes from Greek: πέρκη, romanized: perke, meaning the type species of this genus, the European perch (P. fluviatilis).

Many species of freshwater game fish more or less resemble perch, but belong to different genera. In fact, the exclusively saltwater-dwelling red drum (which belong to a different order Acanthuriformes) is often referred to as a "red perch", though by definition perch are freshwater species. Though many fish are referred to as perch as a common name, to be considered a true perch, the fish must be of the family Percidae.

Species

Most authorities recognize three species within the perch genus:

• The European perch (P. fluviatilis) is primarily found in Europe, but a few can also be found in South Africa, and even as far east on the Southern hemisphere as Australia.^[3] This species is typically greenish in color with dark vertical bars on its sides with a red or orange coloring in the tips of its fins. The European perch has been successfully introduced in New Zealand and Australia, where it is known as the redfin perch or English perch. In Australia, larger specimens have been bred, but the species rarely grows heavier than 2.7 kg (6 lb).
• The Balkhash perch (P. schrenkii) is found in Kazakhstan, (in Lake Balkhash and Lake Alakol), Uzbekistan, and China. It has a dark gray/black color on its dorsal side, but the ventral areas of the fish are a lighter silver or even sometimes green color. The Balkhash perch also displays the vertical bars on its sides, similar to the European and yellow perches. In the latter half of the 20th century, the Balkhash perch was introduced into the basins of the Nuru and Chu rivers. The introduction of these fishes to the Nuru and Chu rivers was successful. Because of this success, the population of Balkhash perch in the Balkhash Lake is rarer now. They are similar in size to the yellow and European perches, weighing around 1.5 kg (3 lb 5 oz).^[4]
• The yellow perch (P. flavescens), smaller and paler than the European perch (but otherwise nearly identical), is found in North America. In northern areas, it is sometimes referred to as the lake perch. This species is prized for its food quality and has often been raised in hatcheries and introduced into areas in which it is not native. These fish typically only reach a size of about 38 cm (15 in) and 1 kg (2 lb 3 oz).

Anatomy

External anatomy

Perch have a long and round body shape which allows for fast swimming in the water. True perch have "rough" or

External anatomy can be used to determine the sex of perch in multiple ways. Perch have two posterior openings located on their abdomen, the anal and urogenital. In males, the shape of the urogenital opening is round and larger than the anal opening. In females, the urogenital opening is often a V- or U-shape which is a similar size to the anal opening. Also, males usually have a more brown-red colored urogenital opening compared to females.^[8]

Internal anatomy

The

testes (sperm-producing) or a pair of ovaries (egg-producing).^[9]

Perch are classified as carnivores, choosing waters where smaller fish, shellfish, zooplankton, and insect larvae are abundant.^[13][14] The perch can be found in the central parts of the United States in freshwater ponds, lakes, streams, or rivers. These fish can be found in freshwater all over the world, and are known to inhabit the Great Lake region, in particular Lake Erie. These fish inhabit bodies of water where vegetation and debris is readily accessible.^[15][16][17] In the spring when the perch chooses to spawn, they use vegetation to conceal their eggs from predators.^[18]

Fishing

Perch are a popular