CONCLUSIONS & RECOMMENDATIONS
5. Conclusions
Benthic fauna and communities display great variability in their component species and abundance over both spatial and temporal scales. Generalizations regarding presence of species on different substrates can be made (e.g., deposit feeding bivalves on mud-silt substrates), but specific statements cannot be derived for individual communities due to the great complexity of these systems. The most significant phyla, in terms of diversity, density and biomass appear to be bivalve and gastropod molluscs, polychaetes, amphipods, and nematodes. In some areas echinoderms and decapod crustaceans contribute significantly to the density and biomass of benthic invertebrates. Meiofauna appears to form a large, but as yet unstudied, component of benthic communities.
Although this report has reviewed the communities in the surrounding areas as indicators of what might be present within St. Georges Bay, it is not possible to extrpolate communities from nearby areas to the bay of interest. The findings of this review indicate that such an approach would be incorrect and misleading. Benthic communities are functions of their substrate and water quality environments, but they can and do vary significantly over short spatial and temporal scales. The mixed substrates of St. Georges Bay, combined with its unusual temperature regime, suggest the presence of mixtures of communities, and growth and biomass, unusual for similar depth waters from elsewhere. The heterogenous nature of St. Georges Bay sediments will probably support an equally heterogenous collection of communities, differing in diversity, species and individual density, biomass, and trophic guilds.
Published research on benthic fauna and communities has been almost non-existent in the last twenty years. There appears to have been a decrease in appreciation of the importance of this component of the marine ecosystem. The benthic system is tightly coupled to the pelagic system via suspended and deposited food and in turn provides a food source and living space for many animals that live in the water column and upper layers. Greater emphasis on the benthic system, including detailed sampling of macro- and meiofauna, is required before any model of St. Georges Bay may be constructed.
6. Recommendations
The following research approaches are recommended for St. Georges Bay in order to better understand benthic dynamics and interactions with the community within the water column. This information is required in order to build a model of the St. Georges Bay ecosystem.
I. Collect unpublished information from government/consultants offices to expand the local database. As well, review the French language publications. This will add to what has been presented here.
II. Sample St. Georges Bay for benthic fauna and community structure. This should include number of species present (diversity), density (species and individual), biomass, trophic structure, and meiofauna. Suggested methodology is SCUBA transects in shallow water and a combination of grab samples and short tows in deeper water. A well designed sampling procedure and schedule is the required first step. Such sampling is necessary and critical if information is to be gathered on the benthos of St. Georges Bay.
III. Three aspects of sampling in St. Georges Bay are strongly recommended for focus:
1) Determination/analysis of feeding guilds (suspension vs. deposit vs. others) on the various sediments;
2) The magnitude of the meiofauna abundance within differing substrate types and it's role in the community; and
3) Interactions between the surface benthic fauna and the community in the water column above the substrate.