Arthropod food web dynamics in the foreland of Qassinnguit Glacier: Predator-prey interactions along a climate-sensitive transect

The Arctic is warming nearly four times faster than the global average, leading to rapid glacier retreat and exposing new glacier forelands. These newly exposed areas provide an exceptional opportunity to study how climate change affects ecosystems, particularly for climate-sensitive arthropods. Understanding these impacts can help predict future changes in biodiversity and ecosystem dynamics under ongoing warming.In this project, we explore arthropod food web dynamics in a Greenland glacier foreland by integrating DNA-based gut content analysis and quantitative activity-density measurements. Using Structural Equation Modelling (SEM), we analyzed both predator diets and arthropod population dynamics across a climate-sensitive transect.Our findings reveal that food web dynamics vary with successional stages: early vegetation stages are characterized by bottom-up control driven by environmental conditions, while later stages show top-down control dominated by predator interactions, largely influenced by warming temperatures. Notably, intense intraguild predation (IGP) was observed in the linyphiid spider Collinsia holmgreni, suggesting that sustained warming could lead to the decline of cold-adapted species in these ecosystems.These insights provide a better understanding of how ongoing Arctic warming affects predator-prey relationships, which is crucial for predicting shifts in biodiversity and ecosystem functioning under future climate scenarios.