Assessing synergistic habitat changes and interspecific relationships of small pelagic fish in the northwest Pacific Ocean
Data files
Feb 24, 2026 version files 12.61 MB
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Data_and_code.zip
12.60 MB
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README.md
3.74 KB
Abstract
Aim: Small pelagic species constitute a critical component of fishery resources in the northwest Pacific Ocean. Understanding the interactions among interspecific relationships, environmental niches, and resource abundance is essential for developing science-based fisheries management. This study aims to investigate the differential habitat responses of small pelagic species in the Northwest Pacific to environmental factors, specifically evaluating the ecological interpretation of interspecific relationships through joint species distribution modeling.
Location: The northwest Pacific Ocean
Taxon: Japanese sardine; Chub mackerel; neon flying squid
Methods: This study examined three economically important small pelagic species from the northwest Pacific Ocean: Japanese sardine (Sardinops melanostictus), chub mackerel (Scomber japonicus), and neon flying squid (Ommastrephes bartramii). Using a joint species distribution model (JSDM) and ecological niche theory, we integrated multiple environmental variables to analyze interspecific associations and patterns of synchronous habitat variation among these species.
Results: The JSDM accurately predicted suitable habitats for all three species, revealing spatial synchrony in habitat suitability. Notably, a positive interspecific (0.9) association is observed between S. melanostictus and S. japonicus, while both exhibit negative associations (−0.84 and −0.95) with O. bartramii. The breadth of suitable ecological niches for key environmental factors and their corresponding response curves offers ecological insights into these interspecific interactions, confirming the dynamic variations in suitable habitat ranges for these species.
Main Conclusions: The interspecific relationships reflected similar species responses to environmental factors and highlighted their occupation of overlapping ecological niches. This consistency in environmental responses may drive synchronized habitat shifts, potentially affecting fluctuations in small pelagic fish abundance.
File Descriptions
"model_code.txt"
Data and commented code for the reproduction of modeling. The distribution data of the three species is not publicly available due to privacy or ethical restrictions. All environmental data and pseudo-absence data were provided in the ".xlsx" files.
variable definitions
Sea Surface Temperature (SST): This variable indicates the temperature of the ocean’s surface water. It is an essential factor for studying species distribution and marine ecosystems.
Chlorophyll-a Concentration (CHL): This variable represents the amount of chlorophyll-a pigment in the water, which is an indicator of phytoplankton biomass. Phytoplankton are microscopic plants that form the base of the marine food web, making this measurement crucial for understanding marine productivity and ecosystem health.
Sea Surface Salinity (SSS): This variable indicates the salt concentration in seawater at the surface. Salinity affects water density and circulation patterns in the ocean, influencing marine species' life and distribution.
Sea Level Anomaly (SLA): This variable represents variations from the average sea level in a given area. It can result from factors like ocean currents, temperature changes, and atmospheric pressure.
Eddy Kinetic Energy (EKE): This variable quantifies the energy in ocean eddies, which are swirling water masses. EKE is important for studying ocean mixing processes, nutrient distributions, and the dynamics of marine ecosystems.
Mixed Layer Depth (MLD): This variable refers to the depth of the upper layer of the ocean where water is well-mixed due to wind and wave action. The MLD influences the distribution of heat, nutrients, and marine organisms.
Dissolved Molecular Oxygen (O2): This variable indicates the concentration of oxygen dissolved in seawater. Oxygen is vital for the survival of marine organisms, making its measurement important for marine species distribution and ecosystem health.
Dissolved Molecular Nitrate (NO3): This variable represents the concentration of nitrate ions in seawater. Nitrate is a key nutrient for phytoplankton growth, and monitoring its levels helps understand primary production and nutrient cycling in marine ecosystems.
Dissolved Molecular Phosphate (PO4): This variable indicates the concentration of phosphate ions in seawater. Similar to nitrate, phosphate is an essential nutrient for marine plants, and its levels influence primary productivity.
Net Primary Production (NPP): This variable signifies the amount of organic matter produced by phytoplankton through photosynthesis minus the amount consumed through respiration. NPP is a critical measure of the productivity of marine ecosystems and overall ocean health.
Units for all variables
SST: Measured in degrees Celsius—°C
CHL: Measured in milligrams per cubic meter —mg/m^3
SSS: Measured in practical salinity units—psu
SLA: Measured in meters—m
EKE: Measured in square meters per second squared—m2/s2
MLD: Measured in meters —m
O2: Measured in millimoles per cubic meter—mmol/m^3
NO3: Measured in millimoles per cubic meter—mmol/m^3
PO4: Measured in millimoles per cubic meter—mmol/m^3
NPP: Measured in milligrams per cubic meter per day—mg/m^3day
All files details
GLO_ENVI.xlsx
The data for the all environmental factors .
pseudo-absence.xlsx
The pseudo-absence data used to establish the model.
Software versions for models
Hierarchical Model of Species Communities: ‘Hmsc’ version 3.0-13
Software version for R
the script was created using R version 4.2.0.