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This is the first update about the recently launched Great Bay Eelgrass Resilience Project. Periodic updates
like this one will help keep communities around Great Bay and others informed and engaged, and will be used
to provide a preview of results as they begin to emerge. Sign up here to receive future updates.
~ Project Updates ~
New collaborative research project launched!
After nearly a year of planning, consultations, and proposal writing, the Great Bay Eelgrass Resilience Project
was officially launched in fall of 2021. Here are the basics of the project.
● Full project title: Resilience and positive feedbacks: Water quality management and eelgrass health in
the Great Bay Estuary, NH/ME
● Project timeframe: Fall 2021 - Fall 2024
● Partners leading the project: University of New Hampshire, Piscataqua Region Estuaries Partnership,
and the Great Bay National Estuarine Research Reserve.
● Funder: NOAA via the NERRS Science Collaborative
● Primary objectives:
○ Improve understanding of what drives eelgrass health and resilience
○ Fill science gaps to help adaptively manage eelgrass and nitrogen in Great Bay.
The team has assembled a Project Advisory Committee that will provide input throughout the project to ensure
results are relevant, trusted and useful. The group includes representatives from the towns around Great Bay
as well as the agencies and organizations involved in protecting water quality and habitats.The current
advisory committee membership is here. If your town or organization would like to participate more actively in
the project, please contact Lynn Vaccaro (contact info is at the bottom).
The Advisory Committee met in January to discuss the project’s collaborative approach and plans for modeling
water flow in Great Bay. The group will meet again on March 25 to discuss plans for the upcoming field season.
We’ll continue to share highlights of Advisory Committee meetings through Updates like this one; please reach
out to the project team or an Advisory Committee member if you’d like more detail.
Project updates and final products will be posted on our project webpage.
Research Updates, Issue #1 Great Bay Eelgrass Resilience Project page 1
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~ So What? ~
Why research eelgrass in Great Bay?
Seagrasses are a vital component of healthy
estuaries here in New England and throughout the
world. They are rooted, flowering plants that grow
underwater and are typically submerged, even at
low tide. Nearly all the seagrass beds found in
Great Bay are composed of a single species
commonly known as eelgrass, Zostera marina.
When healthy, eelgrass forms dense underwater
meadows that provide essential habitat and oxygen
for fish and shellfish. The roots of eelgrass plants
hold sediment in place, while the long leaves slow
waves and tidal currents, causing suspended
sediments to settle out and helping prevent coastal
erosion.
Unfortunately, eelgrass has been declining in Great
Bay over the past 20 years, which is one of the
factors that led EPA to develop the Great Bay Total
Nitrogen General Permit in 2020. This 2 minute
video describes eelgrass trends locally, and this 1
minute video visually compares healthy and less
healthy eelgrass meadows in Great Bay.
Great Bay is not the only place struggling with
these issues - eelgrass populations are declining in
many parts of the US. While eelgrass can handle a
wide range of temperatures, water depths and
salinity levels, the plants, especially seedlings,
need high light levels. In many coastal
areas, excess sediments and nutrients
alter water quality, limiting the amount
of sunlight that can penetrate the
water, which in turn slows or prevents
the growth of eelgrass. Other factors,
such as intense storms and diseases,
can also damage eelgrass meadows.
The Great Bay Eelgrass Resilience
project will closely examine the
connections between eelgrass health,
water quality and water flow patterns in Great Bay.
The team will look at these relationships from two
angles. First, by looking for spatial patterns and
correlations between eelgrass health and different
physical and chemical variables, we will try to tease
out what factors seem to be impacting growth
locally. Second, we will use state of the art
approaches to measure how eelgrass can affect
the water it lives in, potentially improving water
quality and increasing its own resiliency. For
example, to what extent does eelgrass stimulate
denitrification in the sediment, promote the removal
of nitrogen from the water, and improve water
clarity.
Thanks to significant upgrades to wastewater
treatment plants around Great Bay, nitrogen inputs
to the Bay have been declining. With water quality
improving, eelgrass may be better able to recover
and expand, leading to further improvements in the
Bay. Although we are not sure what this project will
reveal, we are eager to collaborate closely with
local and state decision makers to make sure we
are learning from and contributing to the ongoing
management of Great Bay. For example, we hope
this research will spark new ideas for restoring
eelgrass meadows, help prioritize future
investments, and help adaptively manage the Bay’s
water quality.
Research Updates, Issue #1, Winter 2022 Great Bay Eelgrass Resilience Project page 2
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Learn more about eelgrass in Great Bay
● A Case for Restoration and Recovery of Zostera marina L. in the Great Bay Estuary
● Status of Eelgrass, State of the Estuary Report, 201
~ Get to Know Our Team and Advisors ~
Project Lead: Bill McDowell, UNH
As project lead, Bill McDowell will provide overall scientific leadership for the
Eelgrass Resilience project team. Bill is an ecosystem scientist and professor
in UNH’s Department of Natural Resources and the Environment. He also
directs UNH’s Water Quality Analysis Lab. Bill and his lab group study water
quality trends and biogeochemical cycles in streams, forests and watersheds,
with a special focus on how people have impacted nitrogen cycling. He leads
long term research programs in the Lamprey River in NH as well as in the
Luquillo Experimental Forest in Puerto Rico. In his free time, Bill likes to
bicycle ride, fish, and do small construction projects. For this project, Bill is
most excited about using an ecosystem science perspective to understand
how water quality and aquatic plants interact to protect an important habitat.
Project Advisor: Gretchen Young, City of Dover
As a member of the Project Advisory Committee, Gretchen Young will help
this project stay connected to all the work that the cities and towns are doing
to reduce the amount of nitrogen that flows into Great Bay. Gretchen has
worked for the City of Dover’s Community Services Department for 7 years,
and currently serves as their Environmental Projects Manager. Gretchen also
leads the Municipal Alliance for Adaptive Management (MAAM) and the
Seacoast Stormwater Coalition (SSC), which help municipalities coordinate
efforts to protect water quality. In her free time, Gretchen and her family like to
take their three year old golden retriever on hikes and other adventures in the
area. For this project, Gretchen is most excited about continuing to
understand the connections between the health of the Great Bay and the
community surrounding it, and then implementing plans of action that improve water quality in creative ways.
~ Stay Engaged ~
Attend the Bayview Lecture: Eelgrass & the Nitrogen Cycle: Opening the Black Box in Great Bay Estuary,
presented by project team member Anna Lowien on March 23, 2022. You can learn more and register here.
Sign up here to receive future Research Updates. If you have questions or ideas for the project, reach out to a
member of the Project Advisory Committee, or contact Lynn or Cory.
Lynn Vaccaro and Cory Riley
Co-collaborative leads for the Eelgrass Resilience Project
Great Bay National Estuarine Research Reserve
Contact Lynn at Lynn.E.Vaccaro@wildlife.nh.gov or 603-294-0146
Research Updates, Issue #1, Winter 2022 Great Bay Eelgrass Resilience Project page 3