Indirect Effects and Context Dependency in Stream Fish Invasions

• DOI: 10.1111/ddi.13968
• Publication Date: 2025-01-14T01:44:11Z
• Authors: William K. Annis; Lily M. Thompson; Stephen R. Midway; Julian D. Olden; Brandon K. Peoples
• Keywords: Fish kill

ABSTRACT Aim Invasion ecology is replete with a body of well‐supported yet contradictory evidence for numerous invasion hypotheses, likely as result context dependency. Context dependency in studies can arise two ways: (1) apparent , when results differ between solely due to methodical differences, or (2) mechanistic truly ecological processes. One form occurs causally linked factors associated success (hereafter, drivers ) either mask enhance each other's effect on success. Mechanistic occur regional scale processes modify the influence local Together, and give rise conflicting support hypotheses via confounding effects related region‐specific Location 2339 stream segments ecoregions United States. Methods Using fish community data distinct ecoregions, we constructed identical path models estimate direct indirect nonnative richness. We chose one variable index from following categories: propagule pressure, natural abiotic, anthropogenic abiotic biotic factors. Results found through presence effects, which pressure richness were modulated by The differed both regions, providing Main Conclusions Apparent lead hypotheses. Accounting important gaining more general understanding process. Furthermore, because varied regionally, it understand large‐scale that contextualise