Facilitative and Inhibitory Interactions Among Estuarine Meiobenthic Harpacticoid Copepods

Area of Science:

• Marine biology
• Ecology
• Benthic ecology

Background:

• Harpacticoid copepods are key meiofauna in Louisiana estuaries.
• Scottolana canadensis and Pseudostenhelia wellsi are dominant species with distinct lifestyles.
• P. wellsi builds mucus tubes, altering sediment structure.

Purpose of the Study:

• To determine if P. wellsi and S. canadensis facilitate or inhibit colonization by Nitrocra lacustris and Cletocamptus deitersi.
• To investigate the mechanisms behind P. wellsi's facilitation and inhibition of other harpacticoids.

Main Methods:

• Artificial monospecific patches of P. wellsi and S. canadensis were created in lab microcosms.
• Colonization by N. lacustris and C. deitersi was assessed.
• Experiments tested the effects of sediment enrichment and tube structure on colonization.

Main Results:

• P. wellsi tube patches facilitated colonization by S. canadensis and N. lacustris, but inhibited C. deitersi.
• S. canadensis patches were unattractive to N. lacustris.
• Both mucus enrichment and inert tube structure facilitated N. lacustris, but only natural P. wellsi tubes facilitated N. lacustris females and S. canadensis.

Conclusions:

• Species interactions and species-specific effects on the sedimentary environment mediate spatial patterns in harpacticoid communities.
• Spatial patterns are complex and cannot be predicted solely by contrasting species' biogenic effects.