Results of Zooplankton Component

EPA Grant Number: R827072C006
Subproject: this is subproject number 006 , established and managed by the Center Director under grant R827072
(EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).

Center: Alabama Center For Estuarine Studies (ACES)
Center Director: Shipp, Robert L.
Title: Results of Zooplankton Component
Investigators: Graham, William M.
Institution: University of South Alabama
EPA Project Officer: Packard, Benjamin H
Project Period: October 1, 1999 through September 30, 2000
RFA: Alabama Center For Estuarine Studies (ACES) (1999) RFA Text |  Recipients Lists
Research Category: Ecological Restoration , Targeted Research

Objective:

To date we have completed sample processing, enumeration and identification, of all zooplankton collections. Zooplankton assemblage analyses have not yet been conducted; however, the pattern of macrozooplankton biomass (> 153 um) showed strong seasonality with a summertime peak in abundance (June-July). The macrozooplankton community was dominated by calanoid copepods, especially Acartia tonsa, and measures of trophic transfer efficiency were produced for only this species owing to its dominance in the Mobile Bay system. Secondary production of A. tonsa, measured from egg production experiments, peaked during the summer (June-August) with maximum production exceeding 20 mg C m-3 d-1. Copepod production was consistently higher in the lower reaches of Mobile Bay throughout the year. Trophic transfer efficiency (from primary to copepod production) was greatest in July and August, and again consistently highest in the lower Bay stations. Maximal transfer efficiency approached 2.5% during July and was near 0% during November and December owing to very low measured copepod production. There was no apparent coupling between primary and copepod production at the sampling scales of this study. This is in marked contrast to the high degree of coupling we have measured in a similar study conducted in the northern Gulf of Mexico. Gelatinous predators, especially the lobate ctenophore Mnemiopsis leidyi, were most abundant during the summer months (June-August) and often dominated the zooplankton community. Ctenophore maxima were consistently found in the mid-Bay region. This pattern of ctenophore distribution - spatially and temporally - likely contributed to the depression of copepod production in the mid-Bay relative to the lower Bay. As such it appears that ctenophore grazing forced decoupling of trophic transfer to copepods in the mid-Bay region during summer months.

Supplemental Keywords:

RFA, Scientific Discipline, Geographic Area, Water, ECOSYSTEMS, Ecosystem Protection/Environmental Exposure & Risk, Aquatic Ecosystems & Estuarine Research, Ecology, estuarine research, Ecosystem/Assessment/Indicators, Ecosystem Protection, Restoration, Aquatic Ecosystem, Ecological Effects - Environmental Exposure & Risk, Aquatic Ecosystems, Ecological Monitoring, Ecology and Ecosystems, Ecological Risk Assessment, Aquatic Ecosystem Restoration, Ecological Indicators, Gulf of Mexico, sampling processing, Acartia tonsa, estuaries, trophic transfer, Mobile Bay, nutrients, macrozooplankton, Mnemiopsis leidyi, environmental indicators, water quality, Ctenophore maxima, estuarine waters

Progress and Final Reports:

  • Final

  • Main Center Abstract and Reports:

    R827072    Alabama Center For Estuarine Studies (ACES)

    Subprojects under this Center: (EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).
    R827072C001 Fluorescent Whitening Agents As Facile Pollution Markers In Shellfishing Waters
    R827072C002 Red Snapper Demographics on Artificial Reefs: The Effect of Nearest-Neighbor Dynamics
    R827072C003 Stabilization of Eroding Shorelines in Estuarine Wave Eliminates with Constructed Fringe Wetlands Incorporating Offshore Breakwaters
    R827072C004 Interaction Between Water Column Structure and Reproduction in Jellyfish Populations Of Mobile Bay (SGER)
    R827072C005 Effects of Variation in River Discharge and Wind-Driven Resuspension on Higher Trophic Levels in the Mobile Bay Ecosystem
    R827072C006 Results of Zooplankton Component
    R827072C007 Benthic Study Component
    R827072C008 A Preliminary Survey of Macroalgal and Aquatic Plant Distribution in the Mobile Tensaw Delta
    R827072C009 Fisheries-induced changes in the structure and function of shallow water "nursery habitats": an experimental assessment
    R827072C010 Effects Of Variation in River Discharge and Wind-Driven Resuspension on Lower Trophic Levels of the Mobile Bay Ecosystem
    R827072C011 Evaluation of Alabama Estuaries as Developmental Habitat for Juvenile Sea Turtles
    R827072C012 Effects of Salinity Stress on Natural and Anthropogenically-Derived Bacteria in Estuarine Environments
    R827072C013 The Role of Land-Use/Land-Cover and Sub-estuarine Ecosystem Nitrogen Cycling in the Regulation of Nitrogen Delivery to a River Dominated Estuary; Mobile Bay, Alabama
    R827072C014 Environmental Attitudes of Alabama Coastal Residents: Public Opinion Polls and Environmental Policy
    R827072C015 Synthesis and Characterization of an Electrochemical Peptide Nucleic Acid Probe
    R827072C016 Determinants of Small-Scale Variation in the Abundance of the Blue Crab Callinectes Sapidus
    R827072C017 Effects of Estrogen Pollution on the Reproductive Fitness of the Gulf Pipefish, Syngnathus scovelli
    R827072C019 A Model for Genetic Diversity Aquatic Insects of the Mobile/Tensaw River Delta
    R827072C020 Evaluating Trophic Processes as Indicators of Anthropogenic Eutrophication in Coastal Ecosystems: An Exploratory Analysis
    R827072C021 Effects of Anthropogenic Eutrophication on the Magnitude and Trophic Fate of Microphytobenthic Production in Estuaries
    R827072C022 Characteristics of Ship Waves and Wind Waves in Mobile Bay
    R827072C023 Methods Comparison Between Stripping Voltammetry and Plasma Emission Spectroscopy for Metals in Mobile Bay
    R827072C024 Changes in Water Conditions and Sedimentation Rates Associated With Construction of the Mobile Bay Causeway
    R827072C025 Cold-Induced Hibernation of Marine Vibrios in the Gulf of Mexico: A Study of Cell-Cell Communication and Dormancy in Vibrio vulnificus
    R827072C026 Holocene Sedimentary History of Weeks Bay, AL: Human and Natural Impacts on Deposition in a Gulf Coast Estuary
    R827072C027 Shelter Bottlenecks and Self-Regulation in Blue Crab Populations: Assessing the Roles of Nursery Habitats and Juvenile Interactions for Shelter Dependent Organisms
    R827072C028 Predicting Seagrass Survival in Nutrient Enriched Waters: Toward a New View of an Existing Paradigm
    R827072C029 DMSP and its Role as an Antioxidant in the Salt Marsh Macrophyte Spartina alterniflora
    R827072C030 A Preliminary Survey of Aerial and Ground-Dwelling Insects of the Mobile/Tensaw Delta
    R827072C031 Natural Biogeochemical Tags of Striped Mullet, Mugil cephalus, Estuarine Nursery Areas in the North Central Gulf of Mexico
    R827072C032 Resolution of Sedimentation Rates in Impacted Coastal Environments Using 137Cs and 210Pb Markers: Dog River and Fowl River Embayments
    R827072C033 Investigation of the Use of Pulse Amplitude Modulated (PAM) Fluorometry as an Indicator of Submerged Aquatic Vegetation Health in Mobile Bay
    R827072C034 Influence of Invasive Plant Species in Determining Diversity of Aquatic Vegetation in the Mobile-Tensaw Delta
    R827072C035 The Influence of Shallow Water Hydrodynamics on the Importance of Seagrass Detritus in Estuarine Food Webs
    R827072C036 Food Web Interactions, Spatial Subsidies and the Flow of Energy Between the Mobile Bay Delta and Offshore Waters: A SGER Proposal to the Alabama Center for Estuarine Studies
    R830651C001 Meteorological Modeling of Hurricanes and Coastal Interactions: A Stability Study For Vertical Pressure Levels
    R830651C002 Characterization of Glycoprotein Cues Used by the Parasitic Rhizocephalan Barnacle Loxothylacus texanus To Identify Its Blue Crab Host, Callinectes sapidus
    R830651C003 Survey of Diamondback Terrapin Populations in Alabama Estuaries
    R830651C004 An Assessment of Environmental Contaminant Levels in Water and Dragonfly Larvae Tissues from the Mobile/Tensaw Delta