Some peculiarities of the population biology of the ghost shrimp <i>Nihonotrypaea petalura</i> (Stimpson, 1860) (Decapoda: Callianassidae) in coastal waters of Vostok Bay, the Sea of Japan
The population biology of the ghost shrimp Nihonotrypaea petalura from the subtidal of Vostok Bay (Peter the Great Bay, the Sea of Japan) was studied in June 2012 for the first time in Russian waters. On stones and mixed substrates at a depth of 0.2–3 m, N. petalura formed aggregations with an average population density of 9–19 indiv./m 2. The biomass of ghost shrimp aggregations was 15–27 g/m 2 or 1–33% of the average total biomass of macrozoobenthos that included 48 taxa of animals. The maximum burying depth of N. petalura was 52 cm. The ghost shrimps in aggregations were 17 to 63 mm in body length. In the size‑frequency distribution, there were two peaks of abundance contributed by specimens of 24–29 and 39–48 mm in TL. The male to female ratio in ghost shrimps of different size was almost unchanged, nearly 1: 0.9 for the whole population studied. The local differences in the studied indices of N. petalura from Vostok Bay and from other parts of the species area are discussed in connection with the specific features of different biotopes where this species occurs.