Trichiurus japonicus belongs to the order Perciformes, family Trichiuridae, and genus Trichiurus. It is a warm-temperate species that typically forms schools near the seafloor. The single-species catch exceeded 1 million tons in 1995[
1], making it one of the few marine species in China with over one million tons in landing. Currently, the main fishing methods in the East Yellow Sea include bottom trawling and seine netting.
Trichiurus japonicus resources in the East China Sea have been exploited since the 1950s, with catches often ranking first among various species since the late 1950s. Consequently,
Trichiurus japonicus is a key species in domestic fisheries research and management. Many resource management systems in the East China Sea, including fishing bans and protected areas, are based on research findings related to
Trichiurus japonicus resources, primarily focusing on conserving traditional economic fish species, with
Trichiurus japonicus being the primary target [
2].
One of the hot topics in fishery ecology is the spatial distribution characteristics of species and their relationships with environmental factors[
3]. The spatial distribution of fish populations is influenced by a variety of control factors, both external and internal, of which the external control, also known as environmental control, includes hydrological conditions, substrate types, etc., and is generally considered to be the main factor affecting the spatial distribution of fish populations[
4]. On the other hand, population size, age structure, fish condition, diversity, and behavior, etc., internal control factors can also regulate the spatial distribution of fish populations through density-dependent, age-dependent habitat preference, migration ability differences, etc.[
5]. The adaptability and limitation of fish to marine environment are one of the key factors determining their migration, distribution, and movement, and the study of the influence of environmental factors on the spatial distribution of fish populations is of great reference value for fishery analysis, fishing ground exploration, and rational use of fishery resources[
6]. Species distribution model (SDM) is a mathematical model that uses environmental data to predict the spatial distribution of species according to their survival conditions, and has become one of the important methods in the application of conservation biology and ecology[
7]. Widely used species distribution models in fisheries include generalized additive models and generalized linear models[
8,
9], with relatively fewer applications of machine learning methods. As automation and intelligence advance, machine learning algorithms increasingly predict fish abundance and distribution[
10], identify populations[
11], standardize catch per unit effort (CPUE)[
12], and explore relationships between fishery resources and environmental factors[
13,
14], showing distinct advantages. For instance, Chen[
15]developed a forecasting model for Indian Ocean yellowfin tuna fisheries using a random forest model, enhancing the forecasting capabilities of distant offshore fisheries. Hou[
16] researched the modeling and forecasting of South Pacific yellowfin tuna fisheries using six ensemble learning models, improving the accuracy of their predictions. Gao[
17] constructed a forecasting model for mackerel in the East and Yellow Seas employing gradient boosting decision trees, playing a crucial role in managing and protecting mackerel resources. Song built a forecasting model for bigeye tuna in the Atlantic tropical waters using K-nearest neighbors and gradient boosting decision trees, enhancing the accuracy of their model predictions. Currently, research utilizing species distribution models to examine the habitat distribution of ribbonfish remains scarce.
Based on the trawl survey data in the central and southern waters of the East China Sea and the Yellow Sea from 2008 to 2009, this study used random forest model, K-proximity algorithm and gradient lifting decision tree to analyze the distribution characteristics of Trichiurus japonicus and their relationship with environmental factors, and then compared and analyzed the fitting effect and prediction ability of the models. The habitat index was used to predict the distribution of Trichiurus japonicus in the East China Sea and the south of the Yellow Sea, so as to provide a basis for the rational utilization and scientific conservation of its resources, and provide a reference for fishery policy management.