Prey choice order of Crangon uritai as a predator for juvenile Pleuronectes yokohamae

Crangon uritai

日本水産増殖学会

水産増殖

During the spring in the coastal waters of Hakodate Bay the shrimp Crangon uritai is the predominant predator on larval and juvenile marbled sole, Pleuronectes yokohamae. To investigate the prey preferences of C. uritai, P. yokohamae and two other prey species, a mysid Nipponomysis sp. and a gammarid Haustorioides japonicus, were used for predation experiments. Among the three prey organisms studied, Nipponomysis sp. was preyed on first, followed by P. yokohamae, and finally H. japonicus. Prey profitability did not differ between P. yokohamae and Nipponomysis sp., though H. japonicus was less profitable. Nipponomysis sp. was larger, more perceptible, and slower to escape than P. yokohamae. A relatively high abundance of mysid Nipponomysis sp. could restrict and reduce predation on P. yokohamae by C. uritai. Gammarid H japonicus was able to escape relatively more easily, because its harder and slippery skin required more handling time than the other prey, possibly making it an undesirable food source for C. uritai. High perceptibility and low escape ability may be the most important factors affecting prey choice of C. uritai.