Stone loach

About

The Stone loach is an unremarkable bottom fish that is more often found by turning over stones in the stream than seen in the water. In Ukraine, it lives in the rivers of the Carpathians, as well as in the tributaries of the Dnipro, Southern Bug, and Siverskyi Donets. The Stone loach prefers rivers and streams with fast currents and rocky or sandy bottoms.

Its body is cylindrical and almost bare: small scales cover only the sides and do not overlap. The head is flattened, the eyes are small, and there are three pairs of whiskers near the mouth, which the fish uses to sense its prey. The coloration is usually yellow-brown and spotted, and in Carpathian rivers, Stone loaches can sometimes be completely dark. In Ukraine, they do not exceed 15 cm, usually measuring 10–12 cm, and weigh 20–25 g.

During the day, the Stone loach hides among the stones or in other shelters and hardly moves, being most active at night. It tends to be solitary or in small groups, and adult fish can defend their own territory. It feeds on bottom invertebrates, the eggs of other fish, and sometimes algae, while larger Stone loaches catch fry. The Stone loach is very resilient: it can tolerate low oxygen levels and can even breathe atmospheric air.

Spawning begins in spring when the water warms to 13–15 °C, occurring in batches 2–3 times over two months. The female lays adhesive eggs on sand, stones, or plants, and the males guard them for 3–4 days until the larvae hatch. The Stone loach lives for 5–6 years. It is not listed in the Red Data Book of Ukraine and has no industrial significance.

Where in the Carpathians

The map shows where naturalists recorded the species (GBIF, CC0 and CC BY records), not every place it lives. The Ukrainian Carpathians are less studied, so a blank area does not mean the species is absent.

Countries

Ukraine · Czechia · Romania · Serbia · Slovakia

Mountain ranges

Polonynian Ridge, Vihorlat-Gutin Volcanic Ridge, Krasna Polonyna, Skole Beskids, Rivna Polonyna, Gorgany, Chornohora, Maramureș Mountains, Moravian-Silesian Beskids

Altitude belts

Foothills (below 600 m)

When to see it

From naturalists’ observations in the Carpathians (iNaturalist, research grade): the darker the cell, the more often the species is seen that month.

Protection and rules

It is not listed in the Red Data Book of Ukraine.

Red Data Book of Ukraine

Where to fish in the Carpathians

This species is not marked on our water pages yet.

Fishing in the Carpathians ›

FAQ