Lower Trophic Level Monitoring to Support Restoration of Living Resources in Barataria Estuary, Louisiana
USGS researchers are collecting information about lower trophic levels in Barataria Estuary to develop a long-term monitoring plan.
The Science Issue and Relevance: Lower trophic level organisms form the base of the estuarine food web and are essential to providing food to upper trophic levels, known as the consumers, which are the shrimp (trophic level 3), crabs, and fish. In Barataria Estuary, Louisiana, the food web is truncated and dominated by lower trophic level organisms such as primary producers (trophic level 1) of phytoplankton and microphytobenthos that are often consumed by zooplankton and benthic macroinfauna (trophic level 2). However, the lack of spatiotemporal information about these resources produces uncertainty about how they may change in the future. This baseline assessment will provide a Monitoring and Adaptive Management (MAM) Activities Implementation Plan (MAIP) to fill known data gaps and address management needs related to lower trophic level organismal abundances, densities, biomass, and community composition in Barataria Estuary.
Methodology for Addressing the Issue: Four main tasks will help collect more information about lower trophic levels in Barataria Estuary. These include Task 1) Prepare for field sampling in the Barataria Estuary; Task 2) Conduct three years of field sampling and up to another year of associated laboratory analyses; Task 3) Synthesize lower trophic level data and produce a summary report characterizing lower trophic level conditions; and Task 4) Develop a long-term lower trophic level monitoring plan for Barataria Estuary. Specifically, USGS will be responsible for microphytobenthos field sampling and associated laboratory analyses of pigments (via high-performance liquid chromatography, HPLC), cell density, phytoplankton pigments, and associated physical water quality (Task 2); synthesis and reporting (Task 3); and development of long-term lower trophic level monitoring plan (Task 4).
Future Steps: Implementation of the long-term monitoring plan of lower trophic levels (Task 4) can help provide information to inform existing ecosystem models (Comprehensive Aquatic Systems Model [CASM]) that are used to evaluate food web structure and productivity in Barataria Estuary, as well as to evaluate ecosystem impacts from restoration actions.
USGS researchers are collecting information about lower trophic levels in Barataria Estuary to develop a long-term monitoring plan.
The Science Issue and Relevance: Lower trophic level organisms form the base of the estuarine food web and are essential to providing food to upper trophic levels, known as the consumers, which are the shrimp (trophic level 3), crabs, and fish. In Barataria Estuary, Louisiana, the food web is truncated and dominated by lower trophic level organisms such as primary producers (trophic level 1) of phytoplankton and microphytobenthos that are often consumed by zooplankton and benthic macroinfauna (trophic level 2). However, the lack of spatiotemporal information about these resources produces uncertainty about how they may change in the future. This baseline assessment will provide a Monitoring and Adaptive Management (MAM) Activities Implementation Plan (MAIP) to fill known data gaps and address management needs related to lower trophic level organismal abundances, densities, biomass, and community composition in Barataria Estuary.
Methodology for Addressing the Issue: Four main tasks will help collect more information about lower trophic levels in Barataria Estuary. These include Task 1) Prepare for field sampling in the Barataria Estuary; Task 2) Conduct three years of field sampling and up to another year of associated laboratory analyses; Task 3) Synthesize lower trophic level data and produce a summary report characterizing lower trophic level conditions; and Task 4) Develop a long-term lower trophic level monitoring plan for Barataria Estuary. Specifically, USGS will be responsible for microphytobenthos field sampling and associated laboratory analyses of pigments (via high-performance liquid chromatography, HPLC), cell density, phytoplankton pigments, and associated physical water quality (Task 2); synthesis and reporting (Task 3); and development of long-term lower trophic level monitoring plan (Task 4).
Future Steps: Implementation of the long-term monitoring plan of lower trophic levels (Task 4) can help provide information to inform existing ecosystem models (Comprehensive Aquatic Systems Model [CASM]) that are used to evaluate food web structure and productivity in Barataria Estuary, as well as to evaluate ecosystem impacts from restoration actions.