HyDiaD: A hybrid species distribution model combining dispersal, multi-habitat suitability, and population dynamics for diadromous species under climate change scenarios

Diadromous species are particularly vulnerable to climate change because they utilize both marine and freshwater habitat complete their life cycles. Dispersal plays an important role in restraining the distribution of plant animal species, is a key mechanism allow diadromous adapt changes suitability, but it often not included models that explore population trends under scenarios. The objective this study was develop model estimate potential shifts populations Atlantic area Europe two scenarios multiple global models. To address question range-shift responses, hybrid approach for (HyDiaD) developed incorporated components: i) statistical static suitability describing influence environmental factors on occurrence, ii) biological processes relevant such as demography dispersal dynamics. Hybrid were using novel between-catchment dynamics specific each species. Occupancy data subset Area catchments first validated by regional experts, boosted regression trees applied within catchment based historical physical climatic predictors from continental domains. Habitat then used local growth. Results different-sized compared time series spawner density saturation rate, which estimated how much available being utilized. Many species-specific values HyDiaD through survey group consensus reached calculating weighted averages. shad (Alosa alosa A. fallax) projected annually 1951 2100. Projected indicated XXIst century scenarios, expected increase fallax, decrease alosa. also rate annual variability alosa, southern part its range. Future studies can other