Session Lead: Brooke Landry
Session Co-lead: Becky Golden
Session Format: Combo Presentation and Panel Discussion
Abstract:
Submerged aquatic vegetation (SAV) in the Chesapeake Bay serves a multitude of ecosystem services and is one of the Bay’s most important habitats. It also serves as an easily visible indicator of Bay-wide restoration progress. Because of its value, the Chesapeake Bay Program set a Bay-wide SAV restoration target of 185,000 acres, with interim targets set for 2017 (90,000 acres) and 2025 (130,000 acres). The 2017 SAV Restoration Target was exceeded two years early (in 2015) and has exceeded the target for the last four years (2015-2018). Management actions in the form of N and P reductions were shown to facilitate this SAV recovery (Lefcheck et al. 2018) and we are on track to achieve our next SAV restoration target of 130,000 acres by 2025 if we continue on the current overall trajectory.
Our capacity to continue on the current overall trajectory, however, is not guaranteed. Extreme and/or prolonged weather events and Bay conditions associated with a changing climate, as well as multiple shallow-water use conflicts, may impact SAV restoration goal attainment. 2019 was the highest flow year on record, according to the USGS. The extreme and prolonged precipitation, which caused salinity changes and increased nutrient and sediment loading, impacted SAV in areas throughout the Bay. There was a substantial loss of eelgrass in the polyhaline as well as an extensive widgeongrass loss in much of the poly- and mesohaline. Although acreage data is not yet available, it is likely that 2019 SAV extent will be below the 2017 target of 90,000 acres.
If 2019 proves to be an anomaly, SAV recovery will likely resume and continue along the established trajectory in 2020. If more extreme conditions become the new norm, however, increased mitigation efforts will be necessary. To effectively mitigate standard as well as climate change impacts, both direct and indirect, more detailed monitoring will also be necessary. As such, the Chesapeake Bay Program’s SAV Workgroup is in the process of expanding the Baywide SAV monitoring program to include an SAV sentinel site program and the Chesapeake Bay SAV Watchers program, a volunteer monitoring program for citizen scientists. Along with the Bay-wide aerial survey, these will form a three-tiered hierarchical monitoring program that will maximize our efficiency and forecasting capabilities.
For this proposed session, we anticipate three to four twenty-minute oral presentations that delve into the details of the Chesapeake Bay SAV introduced above, followed by a panel discussion and Q&A period. Two hours would be an ideal amount of time for this session, but we can be flexible based on overall scheduling needs.