The Chropyňský rybník – Chropyně Fishpond NNM lies on the south-western edge of the town of Chropyně in the Zlínský kraj – Zlín Region and has been protected since 1954 on an area of 24.36 hectares at an elevation of 191 metres above sea level.
The Chropyně Fishpond lies on the edge of the central Moravian alluvial plain near the confluence of the Morava and Bečva rivers. The area lies on rich deposits of sand and gravel, which are overlain by flood loams. The soil around the fishpond is of the Fluvisol and Gley types.
The predominant tree species on the banks of the pond are hybrid black poplars (Populus x canadensis) and alders (Alnus glutinosa), along with other trees such as white willow (Salix alba), white poplar (Populus alba) and black poplar (Populus nigra). Wild privet (Ligustrum vulgare) is the most common species in the shrub layer, along with elder (Sambucus nigra). A littoral belt has developed around parts of the pond with lesser bulrush (Typha angustifolia), with enclaves of bulrush (Typha latifolia) in places. Around the island and the northern part of the pond the littoral growths are predominantly of common reed (Phragmites australis). We can also find smaller growths of slender tufted sedge (Carex acuta), lesser pond sedge (C. acutiformis) and greater pond sedge (C. riparia), accompanied by reed sweet-grass (Glyceria maxima), sweet flag (Acorus calamus), yellow iris (Iris pseudocorus), branched bur-reed (Sparganium erectum) and others. The pond is also home to significant plants which grow on the water surface, such as water chestnut (Trapa natans), common duckweed (Lemna minor), rigid hornwort (Ceratophyllum demersum) and lesser pondweed (Potamogeton pusillus).
The Chropyně Fishpond has been an important ornithological locality since the late 19th century and 133 bird species have been recorded here recently, of which 31 species nest here. The most abundant birds are the black-headed gulls (Larus ridibundus) with a colony of 1200 pairs nesting here. Other notable breeding birds include the little bittern (Ixobrychus minutus), which now only nests here irregularly, water rail (Rallus aquaticus), great reed warbler (Acrocephalus arundinaceus), great crested grebe (Podiceps cristatus), black-necked grebe (Podiceps nigricollis), which now only nests here irregularly, and others.
We can also observe amphibians such as the edible frog (Rana klepton esculenta) and marsh frog (Rana ridibunda) around the pond, as well as an abundance of grass snakes (Natrix natrix). A notable and rare species of ground beetle which can be found here is Pterostichus aterrimus which is bound to preserved lowland or river valley wetland habitats.