Predation av sandräka (Crangon crangon) på juvenil piggvar (Psetta maxima) och juvenol skrubbskädda (Platichtys flesus) : betydelse av yngelstorlek för överlevnad hos piggvar och skrubbskädda efter bottenfällning
2011
de Gouveia, Manuela
Turbot (Psetta maxima) and flounder (Platichthys flesus) are two species of flatfish both having their nursery areas around the shores of Gotland in the Baltic Sea. The common brown shrimp (Crangon crangon) is a known predator on newly settled plaice (Pleuronectes platessa) in the North Sea area and is also found in the Baltic Sea. Experiments were carried out to see if the brown shrimp is predating on juvenile turbot and flounder, and if so on which sizes, and if the brown shrimp prefers any of the flatfish species, and also to see if there is a difference between day and night in density of the shrimp, i.e. when the fish might be subjected to predation. The results showed that predation decreased with size for both turbot and flounder. The brown shrimps prefer small flatfishes, size class <30 mm, without any species preference. The shrimp abundance was higher during the night at one out of three locations around Gotland. More data is, however, needed to conclude that it is more active during the night.
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