Study of the Population Dynamics and Habitat Suitability of Oratosquilla oratoria in the Coastal Waters of Northern Shandong Peninsula, China

Fishing pressure shapes fishery-resource populations, but habitat suitability is often overlooked in spatial management. In this study, we investigated the population dynamics and habitat suitability of the mantis shrimp, Oratosquilla oratoria, in the northern Shandong Peninsula using surveys from 50 coastal stations in May and August 2024, comprising 6504 individuals. The population exhibited negative allometric growth, with modeled growth accelerating around June. Fishing mortality was 1.44 a−1 and the exploitation rate was 0.53. Current F exceeded F0.1 (0.90 a−1) and was close to F20% (1.46 a−1), while the length at first capture (Lc = 6.48 cm) was substantially lower than the optimal length at first capture (Lcopt = 10.34 cm), indicating substantial fishing pressure and premature capture of small individuals. GAMs provided better in-sample fits than GLMs. Salinity and water depth were important predictors in both seasons, with nitrite nitrogen retained in spring and total phosphorus and pH retained in summer. Model-derived habitat suitability showed seasonal spatial redistribution, and high-suitability areas experienced greater fishing pressure. We therefore propose a preliminary spatially differentiated management scenario, including reduced fishing effort and candidate Lc reference values of 11.89 cm and 8.63 cm for high- and moderate-suitability areas, respectively.