Science » Invertebrates
The figure below is an example of benthic invertebrate taxa and abundance within the mudflats in San Francisco Bay. Cores were taken along an elevation gradient from shore (core 0) to a deep water channel (core 8).
Benthic invertebrates provide critical food resources for fish and birds that use the estuary. Three habitat types (slough, mudflat, and marsh edge) will be sampled at selected locations with three replicates to characterize and track the colonization of the benthic invertebrate community. At each location benthic cores (10 cm diameter, 10 cm depth) will be taken annually in the fall (during bird migratory season). In addition, physical variables that may effect invertebrate composition such as water quality, and sediment characteristics (particle size) will be taken during invertebrate collection. Samples will be screened (0.5 mm sieve) and stored in ethanol with rose Bengal dye to help distinguish organic tissues.
Surface and terrestrial invertebrates including salt marsh insects will be sampled with sweep netting (3 sweeps at each location) and fall-out traps. Invertebrates will be sieved through a 0.5 mm mesh and samples will be preserved and archived in alcohol. As additional funds become available, samples will be sorted, identified to the lowest possible taxa, enumerated, and weighed to the nearest 0.001 g (wet weight) with a high precision scale or using equations to estimate wet weight based on count data. Unidentified invertebrates will be stored in alcohol for later identification by an invertebrate specialist.