Seasonal dynamics of fish assemblage in a pond canal

Abstract

The annual dynamics of fish assemblage in a pond-connecting canal of a South Moravian pond aquaculture facility was studied to reveal potential assemblage effects on pond stocks and vice versa. The species richness of fish assemblage and seasonal dynamics of its development were predominantly dependent upon the fish stock of the interconnected ponds (particularly due to escapees during the period of pond harvesting), which contributed to a considerable increase of commercial fish species occurrence. Using a seasonal parameter, the season proved to have a major impact on fish assemblage dynamics (r = À0.71, P < 0.001). Spring samples were dominated by commercial fishes of aquaculture origin (mainly Cyprinus carpio). Occurrence of several fish species originating from the wild (bleak, Alburnus alburnus, chub, Leuciscus cephalus and roach, Rutilus rutilus) was also reported.The pond canal was found to be an important reservoir site of persistent survival and potential subsequent spreading of some undesirable alien fishes such as topmouth gudgeon (Pseudorasbora parva) and gibel carp (Carrasius auratus). Moreover, more attention should be paid to the potential negative impacts of all fishes of aquaculture origin upon the natural ecosystem and to the adverse effects due to the immigration of wild fish into aquaculture pond farming units.

Long‐term changes in the fish assemblage structure of a shallow eutrophic reservoir (Lake Hídvégi, Hungary), with special reference to the exotic Carassius gibelio

“…By 1986 the inundation of Lake Hídvégi had been completed, thus, the year of 1986 could be defined as the pioneer phase of the reservoir. The escape of these fish might occur during floods, in fact, the phenomenon was actually documented in some cases (Musil et al, 2007;Erős et al, 2012). However, the fish assemblage in 1986 was definitely dominated by bleak, which species is considered sensitive to high ammonia concentrations (Lindén et al, 1979).…”

Desiccation frequency drives local invasions of non-native gibel carp (Carassius gibelio) in the catchment of a large, shallow lake (Lake Balaton, Hungary)

“…But this has not been explicitly tested by studying the communities of fish ponds of the Balaton catchment. More evidence on the high persistence of C. gibelio and P. parva in aquaculture systems and especially in their water-supply canals were provided from South Moravia region of the Czech Republic (Musil et al, 2007). According to our presence-absence data, some non-natives were amongst the most frequent fish species, occurring at every (C. gibelio) or almost every (P. parva, Lepomis gibbosus (Linnaeus, 1758)) site.…”

Piscivorous fishes diet dominated by the Asian cyprinid invader, topmouth gudgeon (Pseudorasbora parva)

“…The fish assemblage in this semi-natural habitat strongly depends upon the pond farming process (fish stocking and harvesting) and is dominated by commercial fishes. The pond canal was found to be an important reservoir of persistent survival of alien fish like the topmouth gudgeon, originating from pond aquaculture units (Musil et al 2007). …”

“…The monitoring of fish populations in a small connecting canal with regular occurrence of topmouth gudgeon (Adámek & Siddiqui 1997, Musil et al 2007) was a unique opportunity to look in situ for its role in the diet of piscivorous fishes.…”