One of the biggest challenges in conservation science is predicting the impacts of multiple co-occurring stressors on species persistence. In recent decades, growing evidence suggests that many threats are acting interactively, particularly climate change and land cover alterations. Species with low dispersal capacity and restricted habitat ranges are especially vulnerable to these changes. The Japanese crayfish (Cambariodes japonicus) is a sole indigenous crayfish in northern Japan. However, local extinctions of this species are occurring rapidly and extensively across its range within the past few decades. Despite this, research on the drivers of Japanese crayfish local extinction remains limited, especially regarding the interactive effects of multiple stressors. Therefore, this study aims to analyze how land-use and climate stressors affect the areas where Japanese crayfish were previously present.
     We collected over 500 sites where Japanese crayfish were previously investigated in past surveys. Using Geographic Information System (GIS), we created buffer zones at multiple spatial scales around these sites. Within each buffer, we calculated land-use composition, including forest, agricultural, and urban areas. For climate variables, we incorporated the average daily minimum temperature of the coldest month, the average daily maximum temperature of the warmest month, total precipitation in the wettest month, and total precipitation in the driest month as explanatory variables. All historical monthly climate data were generated at 1km resolution. For each buffer scale, we conducted logistic regression analysis to access the influence of three land-use types and four climate stressors on Japanese crayfish existence. The best model for each buffer scale was selected based on AIC values.
     The interaction of urban area and minimum winter temperature was identified as the strongest indicator for estimating crayfish presence/absence. Our results showed that across all buffer scales, urbanization alone had a negative effect on crayfish presence probability. However, the interaction between urban area and minimum winter temperature became increasingly positive as buffer size increased, suggesting that higher minimum winter temperatures may mitigate the negative effects of urbanization at larger spatial scales. This finding indicates that while small-scale urbanization can disrupt crayfish habitats, broader-scale environmental factors, such as temperature, may play a crucial role in shaping their persistence.