Benthic biology and ecology
Lead Scientist/Project Manager: Jim Barry

Lead Engineer: Brent Roman

This is a continuing project, dealing with seafloor community dynamics and benthic-pelagic coupling, biological consequences of deep-sea CO₂ disposal, and cold seep biology.

Seafloor community dynamics and benthic-pelagic coupling

We are attempting to compare sites within Monterey Canyon  to those unaffected by the canyon, to study the relative importance of canyon dynamics transporting organic materials  and influencing benthic deep-sea communities. The project will also continue development of benthic instrumentation towards integration with the MARS cabled observatory. Analysis of video transect data will quantify spatial and temporal changes in benthic megafaunal populations.  

Biological consequences of deep-sea CO₂ disposal

We will continue studies of animal tolerance to CO₂ / pH plumes and physiological studies of pH compensation and metabolic depression for deep-sea organisms. We are assessing results from past field experiments and will perform one or two experiments in 2003 focusing on other animals and revised experimental designs for CO₂ exposure. In addition to analyses of field experiments, laboratory studies will continue, with detailed physiological studies of invertebrates and fishes.

Cold seep studies have examined the distribution of seep fauna (especially vesicomyid clams) in relation to the pore fluid chemistry (particularly sulfide) of seep habitats. We have shown that strong links exist between the blood physiology of clams and their distribution among seep habitats. Experiments are now in progress to evaluate the role of physiology in mediating competition for space among species inhabiting the same seeps. We hypothesize that the evolution of shell shape in vesicomyid clams is related both to the distribution of sulfide in the sediment and to the spatial distribution of seeps and clam mobility. Planned experiments will test this hypothesis. Studies of mat-forming, sulfide-oxidizing bacteria from seep habitats will be done in collaboration with Doug Nelson (University of California, Davis).