Response of Terrestrial Arthropod Assemblages to Coastal Dune Restoration

To restore historical dune vegetation, substantial effort has been made to remove the invasive plant species, European beach grass (Ammophila arenaria), from coastal dunes of California, USA. However, little effort has been made to examine the response of terrestrial arthropod assemblages to coastal dune restoration. We sampled terrestrial arthropods at 6 dune restoration sites to determine the response of the arthropod communities to vegetation restoration along the central and northern coast of California. Using pitfall traps, we examined restored and adjacent unrestored foredunes and collected reference data from dunes that had not been invaded by European beach grass. Both arthropod abundance and richness were significantly higher on restored and uninvaded dunes than on unrestored dunes. However, we detected no difference in arthropod richness and abundance between restored and uninvaded dunes. The species composition of the arthropod community reflected greater similarity of geographically adjacent sites, rather than similarity within treatments. We conclude that restored dunes provide higher quality habitat for terrestrial arthropods than unrestored dunes dominated by European beach grass, but longer-term studies are needed to determine if restoration efforts will be effective at fully restoring historical arthropod assemblages.