| Covariate | Justification | Refs |
|---|---|---|
| AGI | Metabolic and thermal drivers that may influence habitat use. | Clarke et al., 2021 |
| Bathy | Observed juv. mako associations with bathy contours, proxy for light, salinity, pressure, and temperature. Observed influence surrounding bathy features where prey may aggregate. | Brodie et al., 2018; Sepulveda et al., 2004 |
| Bathy sd (rugosity) | Proxy for habitat complexity and may influence prey availability. Squid abundance associations with shifts in bathy such as sea mounts. | Suca et al., 2022 |
| Chl-a | Proxy for productivity and prey aggregations (including SDMs for Jumbo/Humboldt squid and Pa. Saury). Observed seasonal movements within the CCS coinciding with peaks in chl-a. | Brodie et al., 2018; Ramos et al., 2017; Paulino et al., 2016; Nasby-Lucas et al., 2019; Syah et al., 2016 |
| MLD | Association with MLD and mako vertical habitat use. MLD effects the vertical water column structure (25-200m depth) and distribution of nutrients. | Nasby-Lucas et al., 2019; Brodie et al., 2018 |
| DO | Physiological oxygen demands and suggested to constrain the vertical movement of Io. Shoaling OMZ may result in habitat expansion for prey species. | Nasby-Lucas et al., 2019; Ramos et al., 2017; Stewart et al., 2014 |
| Salinity | Observed to influence common prey item presence. Not as consistently included in squid lit as other vars (SST, Chl, NPPV). | Ramos et al., 2017; Yu et al., 2019; Stewart et al., 2014; Nasby-Lucas et al., 2019; Hsu et al., 2021. |
| Temperature | Physiological temperature effects on makos and prey. | Nasby-Lucas et al., 2019; Adams et al., 2016; Brodie et al., 2018; Ramos et al., 2017; Yu et al., 2019; Paulino et al., 2016; Succa et al., 2022; Syah et al., 2016; Hsu et al., 2022 |
| UO | Proxy for upwelling. Jumbo squid larval associations with seasonal upwelling. Studies have found catches of squid are higher during strong upwelling years. Some associations with upwelling in CCS and mako shark movements. | Ramos et al., 2017; Yu et al., 2019; Stewart et al., 2014; Nasby-Lucas et al., 2019 |
| UO stress | Proxy for upwelling and influential covariate for Brodie et al., 2018 models. Influence formation of frontal systems. | Succa et al., 2022 |
| VO | Proxy for upwelling. Jumbo squid larval associations with seasonal upwelling. Studies have found catches of squid are higher during strong upwelling years. Some associations with upwelling in CCS and mako shark movements. | Ramos et al., 2017; Yu et al., 2019; Stewart et al., 2014; Nasby-Lucas et al., 2019 |
| VO stress | Proxy for upwelling and influential covariate for Brodie et al., 2018 models. Influence formation of frontal systems. | Succa et al., 2022 |
| SSH | Indicator of divergence and convergence. SSH anomoly used more frequently in prey species SDMs. | Succa et al., 2022 |
Mako hSDM covariate exploration across depth layers
For each of the figures below, I have visualized what the covariate values are for the Background pseudo absence positions and observed positions across three depth layers (0m, 60m, and 250m). I have also explored the covariate values using the full range of the available positions using environmental data from Copernicus Marine and Environment Monitoring Service (CMEMS).
Background PA positions were developed at random and at a 1:1 ratio with the number of observed locations.
Covariate summary plots for all sharks
Covariate selection justification
Map of obsv. positions
Each color represents a different shark track. The tracks are made up of the interpolated state space model positions generated by with the aniMotum package using a time step of 29 hours (the mean time step between positions from the raw data).
Reading layer `mako' from data source
`C:\Users\nazar\OneDrive\Documents\R\Projects\juv_mako_hSDM\data\PAs\background\psat_spot_domain\mako.shp'
using driver `ESRI Shapefile'
Simple feature collection with 1 feature and 1 field
Geometry type: MULTIPOLYGON
Dimension: XY
Bounding box: xmin: 208.92 ymin: 2.98 xmax: 254.59 ymax: 47.37
Geodetic CRS: GCS_unknown
Broad covariate comparisons at 0m
The figures below only represent covariate values for observed positions. PA positions were omitted from this analysis due to the quantity.
Broad covariate comparisons at 60m
The figures below only represent covariate values for observed positions. PA positions were omitted from this analysis due to the quantity.
Broad covariate comparisons at 250m
The figures below only represent covariate values for observed positions. PA positions were omitted from this analysis due to the quantity.
Abiotic covariate comparisons at 0m
Below are some comparisons of the covariate values relative to each other for the observed positions (covariate values at PA positions are excluded).
Abiotic covariate comparisons at 60m
Below are some comparisons of the covariate values relative to each other for the observed positions (covariate values at PA positions are excluded).
Abiotic covariate comparisons at 250m
Below are some comparisons of the covariate values relative to each other for the observed positions (covariate values at PA positions are excluded).
Metabolic demand covariate comparisons at 0m
Below are some comparisons of the covariate values relative to each other for the observed positions (covariate values at PA positions are excluded).
Metabolic demand covariate comparisons at 60m
Below are some comparisons of the covariate values relative to each other for the observed positions (covariate values at PA positions are excluded).
Metabolic demand covariate comparisons at 250m
Below are some comparisons of the covariate values relative to each other for the observed positions (covariate values at PA positions are excluded).
AGI covar comparisons at 0m
Below are some comparisons of the covariate values relative to each other for the observed positions (covariate values at PA positions are excluded).
AGI covar comparisons at 60m
Below are some comparisons of the covariate values relative to each other for the observed positions (covariate values at PA positions are excluded).
AGI covar comparisons at 250m
Below are some comparisons of the covariate values relative to each other for the observed positions (covariate values at PA positions are excluded).
Lat/lon covar comparisons at 0m
Below are some comparisons of the covariate values relative to each other for the observed positions (covariate values at PA positions are excluded).
Lat/lon covar comparisons at 60m
Below are some comparisons of the covariate values relative to each other for the observed positions (covariate values at PA positions are excluded).
Lat/lon covar comparisons at 250m
Below are some comparisons of the covariate values relative to each other for the observed positions (covariate values at PA positions are excluded).
