Fig 1.
A conceptual diagram of the trait-based vulnerability and impact approach.
(A) The Butt et al. (2022) trait-based vulnerability model with (B) the incorporation of life stage variability into the model, and (C) the inclusion of life stage and stressor spatial distributions to calculate spatially-explicit impact. For each trait, each life stage is assessed a trait value represented by the different colour saturations. Vulnerability is calculated for each stressor (e.g., sea surface temperature, pollution, and bycatch) resulting in different vulnerability estimates for each stressor (represented by the grey boxes in (A) and (B)). Life stage and stressor spatial distributions are then incorporated with the vulnerability estimates to calculate impact for each life stage and stressor (represented in (C)). (Turtle icon from stock.adobe.com; Maps made with Natural Earth).
Table 1.
Green sea turtle traits modified from the original Butt et al.
[20] framework. Shown here are the seven traits from the Butt et al. [20] framework with trait values that can be subdivided for individual species’ life stages. The full 42 traits and associated trait values for each life stage of the green sea turtle are available in the S1 Table.
Fig 2.
Comparison of spatial distributions for green sea turtle life stages in the Greater Caribbean Region.
(A) An AquaMaps distribution for green sea turtles bounded to a specified area of the Greater Caribbean Region. (B) An example spatial distribution for a hatchling life stage from two major nesting beaches. (C) An example spatial distribution for a gyre life stage. Each grid cell is 0.5° x 0.5°. Note that the polygons for (B) and (C) are merely estimates and may not represent actual distributions for these life stages from these specific beaches. (Maps made with Natural Earth).
Fig 3.
Green sea turtle trait-based vulnerability to 23 individual stressors.
Vulnerability shown without consideration of life-history stages (Butt et al.) and with consideration of four life stages using different colours for each stage. The mean vulnerability to all stressors for each life stage is represented by the horizontal lines. Each point represents a single estimate of trait-based vulnerability for each life stage and stressor.
Fig 4.
Kernel density estimates of the impact on the green sea turtle of marine heat waves.
The kernel density estimates reflect the distribution of grid cell impact estimates for marine heat waves across the spatial distribution for each life stage. Impacts from the stressor were calculated for three spatial distributions: AquaMaps (grey), the gyre polygon estimate (green), and the hatchling polygon estimate (orange). The variability in each life stage compared to the Butt et al. stage exemplifies the effect of stressor spatial distributions for individual life stages of a species. Comparing within life stages for gyre and hatchling distributions shows the effect of life stage distributions compared to adult-focused species distributions such as AquaMaps.