Tůň u Kostelan

Tůň u Kostelan is a small but ecologically valuable nature reserve on the left bank of the Morava River, about 200 meters southeast of the village of Kostelany nad Moravou in the Zlín Region of the Czech Republic. The protected area covers just 1.2 hectares and sits at an elevation of roughly 175 meters above sea level. It was declared a nature monument (přírodní památka) in 1997.

What is this place?

At the heart of the reserve lies an oxbow lake — a former channel of the Morava River that was cut off from the main flow after the river's course was regulated, gradually turning into a closed body of water. Its distinctive horseshoe shape and deeply cut, steep banks are traces of the river's earlier path before it shifted direction. Oxbow lakes like this one are a typical feature of large lowland river valleys, but many disappear over time due to silting and plant succession, which is why well-preserved examples such as this one have been placed under protection.

Why is this site protected?

Tůň u Kostelan is one of the last remaining sites for water chestnut (kotvice plovoucí) in the northern part of the Slovácko region. This rare floating aquatic plant, known for its spiky, nut-like fruit, was once widespread in oxbow lakes and floodplain waters along major Central European rivers, but its populations have become scarce due to river regulation and the loss of suitable habitat. The presence of this species was one of the main reasons the oxbow lake received legal protection.

What plants and animals live here?

Alongside the water chestnut, the waters and banks of the oxbow support other characteristic wetland and reed-bed plants: frogbit, forming dense mats on the water's surface, marsh marigold, arrowhead with its distinctive arrow-shaped leaves, bur-marigold, and common reed, which forms a belt of reed vegetation along the shoreline. This diversity of aquatic and shoreline vegetation creates a mosaic of habitats that supports a rich variety of animal life.

Tůň u Kostelan also serves as an important site for amphibians and reptiles. The calm, warm waters of the oxbow, surrounded by lush vegetation, provide favorable conditions for amphibian breeding as well as feeding and shelter for reptiles associated with aquatic and waterside environments.

How to get to Tůň u Kostelan?

The reserve lies immediately next to the village of Kostelany nad Moravou, in the Uherské Hradiště district of the Zlín Region. Its proximity to the Morava River valley places it within a broader natural context typical of the region, known for its numerous oxbow lakes and wetlands accompanying the river.

Frequently asked questions

What is Tůň u Kostelan? It is a small nature monument covering 1.2 hectares, protecting an oxbow lake of the Morava River near the village of Kostelany nad Moravou.

Since when has the area been protected? It received protected status in 1997.

Which plant species makes this site especially valuable? Water chestnut (kotvice plovoucí) — one of the last remaining sites for this species in the northern part of the Slovácko region.

What animals can be found here? The reserve is an important habitat for amphibians and reptiles associated with aquatic environments.