Maxent Model Predictions of Climate Change Impacts on the Suitable Distribution of Crayfish Aquaculture in China

Background: Red swamp crayfish (Procambarus clarkii) is one of the most economically important farmed aquatic species in China. However, it is also a famous invasive species in the world. Methods: The present study simulated near current (1970-2000) and future (2030s, 2050s) suitable distribution areas of P. clarkii aquaculture in China under 4 climate scenarios (SSP126, SSP245, SSP370 and SSP585) and screened out the dominant factors affecting the distribution as well, using the MaxEnt model with 60 effective distribution points. Result: The results showed that mean AUC was 0.986, which indicated a better forecast. The highly suitable aquaculture areas for crayfish were Hubei, Hunan, and Anhui Province. The important environmental factors affecting the distribution of P. clarkii were mean temperature of warmest quarter, precipitation of wettest quarter, isothermality and temperature seasonality. Compared to the present-day predictions, the total area of suitable distribution (general-, medium- and high-suitability) gradually increased in the 2030s and 2050s. The ranking of the total area under different climate change scenarios were SSP370 greater than SSP585 greater than SSP126 greater than SSP245 in the 2030s and SSP585 greater than SSP370 greater than SSP126 greater than SSP245 in the 2050s, indicating that as the greenhouse gas emissions increase, the distribution of P. clarkii was likely to increase. It was of note that the area of high-suitability distribution for SSP585 greatly increased, but for SSP245 greatly decreased in the 2050s. This suggested that we should attach great importance to the ecological risk of crayfish in China and prevent the blind development of the industry.