Rutgers marine and coastal scientists, working in collaboration with the U.S. Geological Survey, completed an environmental assessment of Barnegat Bay-Little Egg Harbor Estuary and Watershed condition over two decades. Lead investigator Michael J. Kennish (Research Professor, Institute of Marine and Coastal Sciences), Benjamin M. Fertig (Postdoctoral Research Associate, Institute of Marine and Coastal Sciences), and Richard G. Lathrop (Professor, Ecology and Evolution) teamed up to examine stressors and drivers of change that seriously impact this valuable coastal lagoon, one of the most important coastal ecosystems in New Jersey. Sponsored by the U.S. Environmental Protection Agency, New Jersey Department of Environmental Protection, and the New England Interstate Water Pollution Control Commission, this work provides one of the most detailed ecological assessments ever conducted on a New Jersey estuary.
The ecosystem-based study (“Assessment of Nutrient Loading and Eutrophication in Barnegat Bay-Little Egg Harbor, New Jersey in Support of Nutrient Management Planning”) is the culmination of a multi-year, interdisciplinary research effort. The project characterized and quantified the estuary’s watershed nutrient loading, physical and water quality properties, biological indicators, and impacts.
“This study paints a rather bleak picture of the ecological health of the Barnegat Bay-Little Egg Harbor Estuary,” explains Mike Kennish. Barnegat Bay-Little Egg Harbor is highly eutrophic due to years of nitrogen and phosphorus enrichment. This estuary has experienced low dissolved oxygen concentrations, harmful algal blooms, heavy epiphytic loading, loss of habitat, diminishing hard clam abundance, and other detrimental effects. Since 2004, eelgrass condition has continually declined to a low point in 2010, and macroalgal blooms occurred frequently. The loss of seagrass beds is due in part to light reductions, and has a secondary impact on animal populations inhabiting them. Barnegat Bay-Little Egg Harbor is an estuary in ecological decline.
An index of eutrophication developed by Ben Fertig quantifies the overall condition of eutrophication in the estuary on a scale of 0 to 100, with 100 being the best. This index integrates 74,400 observations among 85 variables for 20 indicators in 6 components and is calculated based on comparisons to ecologically relevant thresholds and is weighted based on multivariate analyses. “Unfortunately, condition has gotten worse over time in much of the estuary,” notes Fertig. Eutrophication condition declined 34% and 36% in the central and south segments from 73 and 71 in the 1990s to 48 and 45 in 2010, respectively. Index scores for overall eutrophication condition are lowest in the north segment (37 during 2010), which has already undergone severe degradation, yet “the silver lining may be modest improvements in the north segment over time,” adds Fertig. Eutrophication Index values in the north segment rose from 14 in 1991 to 50 in 2009, but sharply dropped down to 37 in 2010.
“A holistic management approach that employs multiple corrective strategies must be implemented concurrently to remediate environmental problems observed in the estuary. Nutrient inputs could be controlled by improving stormwater control systems, implementing best management practices, practicing smart development, preserving open space, limiting fertilizer runoff, and supporting public environmental education and awareness,” Kennish recommends. “Well-coordinated actions are critical to improving the ecological condition and resources of Barnegat Bay-Little Egg Harbor.”
The following Rutgers report is a portion of a draft report that has been submitted to the New England Interstate Water Pollution Control Commission (NEIWPCC), who will be reviewing the draft report, together with the New Jersey Department of Environmental Protection and the U.S. Environmental Protection Agency. A final complete report, including a report prepared by the U.S. Geological Survey is expected to be released by NEIWPCC following final review.
of Nutrient Loading and Eutrophication in Barnegat Bay-Little Egg
Harbor, New Jersey in Support of Nutrient Management Planning