By Ruby Gonzelez
Rigid artificial turf, smooth plastic or soft bottle brush?
By Ruby Gonzelez
Pikeperch (Sander lucioperca) demonstrates a preference for the bottle brush as a spawning substrate for their nest, a recent study found.
The study was conducted at the University of South Bohemia in the Czech Republic to determine the spawning substrate preferences of the pikeperch broodstock and clarify some aspects of natural spawning behavior and assess the suitability of the preferred substrates for egg incubation, hatching and larvae production in recirculating aquaculture systems (RAS).
Production of the species in Europe has been increasing over the past 20 years. With 95 percent provided by capture, culturing the species is considered “promising,” especially because of its high market value and flesh quality.
The aquaculture production, however, is variable and does not meet market demand. “Expanding artificial production is necessary to increase reproduction,” cites author, Oleksandr Malinovskyi et al.
Spawning substrate is a critical factor in reproduction of the percids. A nest-building phytophilic or litophilic fish, it chooses roots, vegetation, sand, gravel or turf as egg‐laying substrate.
There is a lack of information about substrate selectivity and the minimum quantity of suitable spawning grounds needed to sustain natural pikeperch populations.
This is the first study of pikeperch concerning selectivity to type and structure of artificial substrates.
The research shows a significantly higher preference for the bottle brush nest over the artificial turf. The plastic nests remained unoccupied.
No difference was observed between substrates in time from stocking of fish to nest occupation and spawning.
After the egg-laying, nests were moved to controlled conditions of a recirculation aquaculture system for incubation.
Hatching rates and larva production did not differ significantly among tested substrates.
Both bottle brush and artificial substrates were found suitable for spawning and incubation in a recirculation aquaculture system.
Synthetic materials, it was cited, prevent water contamination with organic matters during nest incubation in RAS, which is a plus-factor in such an environment.