## 1 Introduction  
Antarctic krill (_Euphausia superba_), as a key species in the Southern Ocean ecosystem ([PERSON] et al., 2016), holds a unique position in the field of global biological resources. It is not only the single species with the largest resource quantity, but also contains considerable economic and ecological values that cannot be ignored. Given the close correlation between its habitat distribution and the marine environment, accurately grasping the dynamic changes in krill fishery resources has become a core and crucial element for improving fishery production efficiency ([PERSON] et al., 2016). The marine environment is one of the key factors affecting the habitat distribution of krill. Numerous studies have shown that environmental variables such as sea surface temperature, sea ice, and chlorophyll concentration significantly influence the spatio-temporal distribution characteristics of krill habitats ([PERSON] et al., 2016; [PERSON] et al., 2016; [PERSON] et al., 2016). In addition, physical spatial factors such as the distance from the shore and the sea surface height also have a significant impact on the distribution of krill ([PERSON] et al., 2016; [PERSON] et al., 2016). Other environmental factors, such as salinity, also have a certain effect on the habitat of krill ([PERSON] et al., 2016), but the significance of their effect remains unclear. Although how these marine environmental and physical spatial factors affect the habitat and fishery distribution of krill has been widely studied, most of these studies rely on fitting the fishing log data of commercial vessels with environmental factors. Since only 8 to 13 global krill vessels conduct fishing activities in the Antarctic FAO 48 fishing area every year, these fishing log data only record the information of fishing location points and have a low spatial coverage rate. Moreover, due to the confidentiality of commercial information, it is difficult for fishery log data from different countries to be shared ([PERSON] et al., 2016). To some extent, this limits people's in-depth understanding of the distribution pattern of krill habitats. Currently, there are mainly two operation methods for krill fishing: the traditional midwater variable-depth trawl (referred to as the \"traditional trawl\" for short) and the pump-suction truss-pole trawl (referred to as the \"pump-suction trawl\" for short) ([PERSON] et al., 2016). Compared with the traditional trawl, the pump-suction trawl connects a fish pump to the cod end and continuously pumps krill to the deck processing workshop through a hose, simplifying the operation process. It can achieve the purpose of continuous fishing without the need for hauling and setting the net, increasing the fishing efficiency by more than 50%. Since 2006, Norway has taken the lead in introducing the pump-suction trawl technology for commercial fishing. Up to now, there are only five krill fishing vessels in the world that adopt this technology. As the two Chinese pump-suction trawl vessels (which first adopted the pump-suction trawl operation method in December 2022) are in the experimental stage and have only one year of fishing time, and there is still a great lack of knowledge about the operation location of the central fishing ground of the pump-suction trawl vessels, it is more reliable to use the vessel positions and operation locations of the three Norwegian pump-suction vessels to simulate and identify the distribution of krill habitats of this fishing method. The Automatic Identification System (AIS), as a modern navigation and position monitoring device, can realize the automatic identification between vessels and the shore end or between vessels, and can accurately provide information including time, latitude and longitude, speed, course, etc., in real time [11].