Differences in environmental condition and location challenge the assumption that translocated species will sustain ecological functioning

Active reintroductions and translocations of species are increasingly being used to re‐establish populations and restore ecological functioning of degraded habitats, but whether functionally important aspects of species–environment interactions observed at donor locations are maintained under different environmental conditions, or at receptor locations, is not clear. Here, we report on the morphology of burrow networks and the contributions to particle reworking generated by a marine opheliid polychaete, Armandia cirrhosa , a species of conservation importance that is being considered for translocation to restore lost populations across a range of lagoonal systems in the southern regions of the UK. Using an experimental approach, we show that changes in environmental conditions (salinity, 7 levels, 15–40) can lead to subtle deviations in some, but not all, attributes of the burrow network and that the contributions that individuals make to particle reworking can differ between donor and receptor locations. Our study provides evidence that differences between locations can alter aspects of how species may behave and mediate specific ecosystem properties, challenging the view that the successful reintroduction or translocation of a species will lead to similar ecological outcomes to those achieved in donor locations. Practical implication . Evaluations of translocation success should move beyond assessment of population persistence and next‐generation recruitment to consider the biotic and environmental context under which species deliver ecological functioning, whilst accounting for the long‐term influence of climate change and anthropogenic forcing. Restoration and conservation efforts that include a focus on maintaining the integrity of species–environmental interactions are more likely to protect species and secure sustainable pathways to ecosystem recovery.