Macroinvertebrate habitat use and the cascading effects of a native and non-native species

Introductions of novel ecosystem engineers to our estuaries and coasts are often associated with strong impacts on the environment, with some altering community and behavioral interactions, especially if they are part of a cascading interaction. In some US Mid-Atlantic soft-sediment mudflats adjacent to salt marshes, the native predatory polychaete Diopatra cuprea preferentially decorates its mucus tube with the invasive red alga Gracilaria vermiculophylla. This may be due to a facilitation cascade between these species, possibly increasing the availability of invertebrate prey for D. cuprea. To determine the effects of facilitation of G. vermiculophylla by D. cuprea on invertebrates associated with algae, we compared communities inhabiting G. vermiculophylla and Ulva spp. decorations using a field manipulation experiment. Additionally, we tested invertebrate habitat-use in the laboratory with a microcosm choice experiment. In the field, the interaction between site, algal spe..., , , # Macroinvertebrate habitat use and the cascading effects of a native and non-native species

These data were used to analyze aquatic invertebrate habitat use, focusing on the Diopatra cuprea and Gracilaria vermiculophylla system at three different sites on the Eastern Shore of Virginia. We analyzed biomass loss of algae in the field, abundance, richness, and community patterns of invertebrates on algae anchored to either D. cuprea tube caps or worm mimics, and habitats which specific aquatic invertebrates used when given multiple options. We found that the common Ulva spp. showed the highest biomass loss, we saw an interaction between site, algal species, and mimics in the field, and we observed a preference for one of the aquatic invertebrates, Gammarus mucronatus to use the G. vermiculophylla habitat over Ulva spp. regardless of worm presence.

Contact Alexander Mott ([[[e-mail]](mailto:[e-mail])]) with any questions. This manuscript is accepted for publication (11/29/24)...,