Virginia Coastal Program: 2003 Coastal Grant Project Description and Final Summary
Project Task:
FY2003 Task 12.08
Grantee:
Department of Conservation & Recreation-Division of Natural Heritage
Project Title:
Seaside Heritage Program: Mapping and Monitoring Phragmites on the Eastern Shore Seaside of Virginia
Project Description as Proposed:
Nationwide, invasive
species have been identified as the Number Two threat to biological
diversity, second only to loss of species and habitat from development
and urban sprawl. The invasive wetland grass known as common reed
(Phragmites australis), hereafter called “Phragmites”,
is one of our most serious and problematic invasive plant species.
Phragmites is found in every U.S. state and is well-established
and increasing in coastal habitats of Virginia. This fast-spreading
plant grows up to four (4) meters tall and forms dense monotypic
stands, crowding out other native marsh plants. Phragmites is long-lived
and spreads rapidly due to its ability to reproduce both by seed
and dispersed rhizome fragments, establishing readily in disturbed
areas. As a result, marsh plant species diversity and habitat quality
are drastically reduced for many kinds of marsh-dependant wildlife.
Phragmites is known to exist in North America, including Virginia,
in two genotypic forms. One form is native to the U.S. and appears
to have been a non-dominant component of diverse eastern seaboard
marsh communities for millennia. Recent DNA studies provide strong
evidence that a distinct, non-native Phragmites genotype is also
present in the U.S., supporting the existing theory that an introduced
strain of Phragmites has been aggressively invading and dominating
coastal marshes and other wetland communities, in part due to a
lack of natural biological control mechanisms. The presence of an
invasive, non-native strain of Phragmites largely explains how and
why the plant has rapidly spread and become dominant over thousands
of acres of wetland communities during the last two decades in the
Northeast and mid-Atlantic regions.
The Virginia portion of the Chesapeake Bay as well as the extensive
estuarine and island wetlands of the Eastern Shore Seaside are currently
experiencing invasion by non-native Phragmites; however, the rate
of this invasion is not known. Establishing a baseline of current
Phragmites distribution and extent will enable quantification of
the invasion extent, provide a sound basis for prioritized control
treatments, and serve as a benchmark for future assessments of control
needs and past treatment effectiveness. Periodic mapping also provides
the basis for evaluation of natural disturbance events that are
in all likelihood factors involved with aiding Phragmites spread.
For example, a summer 2002 lightning-ignited wildfire on Parramore
Island Natural Area Preserve (NAP) – the largest and one of
the most biologically significant Virginia barrier islands –
has raised concern that existing Phragmites patches there will expand
rapidly in the post-fire disturbance environment. Hurricane Isabel
in September 2003 is also expected to be a significant source of
Phragmites dispersal.
The work proposed here for Year 2 of the Seaside Heritage Program
will: 1) Conduct airborne (helicopter) and ground surveys with GPS
position documentation to provide updated and accurate estimates
of Phragmites distribution on the Eastern Shore Seaside, including
re-mapping of Phragmites on Parramore Island Natural Area Preserve
and other barrier islands in the aftermath of Hurricane Isabel;
2) refine existing (Year 1) draft distribution and abundance maps
for Phragmites on the Seaside of the Virginia Eastern Shore by incorporating
additional existing data layers and newly acquired data including
critical wildlife habitats, significant habitats for rare/threatened/endangered
species, and exemplary natural communities; 3) re-establish monitoring
stations established on Parramore Island prior to Hurricane Isabel
but destroyed or compromised by the storm, and repeat (as necessary)
field data collection to establish pre-treatment monitoring baselines;
4) refine preliminary (Year 1) assessments of the effects of wildfire
and hurricane influences on distribution/abundance of Phragmites
at Parramore Island Natural Area Preserve, and 5) assess and report
on changes in distribution and abundance of Phragmites over the
last decade at Eastern Shore/Fisherman’s Island National Wildlife
Refuge.
A separate Program Element (Task 12.09) to be conducted by the Eastern
Shore Field Office of The Nature Conservancy will begin the work
of implementing control measures for patches of non-native invasive
Phragmites at Parramore Island Natural Area Preserve (postponed
from Year 1 due to the effects of Hurricane Isabel), as well as
other priority Seaside locations held in the public interest.
Scope of Work - general
A) Conduct helicopter-based GPS mapping to provide current, accurate
estimates of Phragmites distribution on the Eastern Shore Seaside,
with a focus on post-Isabel Phragmites abundance on the Virginia
barrier islands.
B) Refine draft (Year 1) Phragmites distribution and abundance maps
for the Eastern Shore Seaside.
C) Relocate and/or reestablish monitoring plots destroyed by Hurricane
Isabel, and collect updated baseline pre-treatment monitoring data.
D) Conduct field work and analyses, and complete final report on
the combined effects of wildfire and hurricane influences on the
current Phragmites abundance and distribution at Parramore Island.
E) Conduct field work and analyses, and complete final report on
the spread of Phragmites at the Eastern Shore/Fisherman’s Island
National Wildlife Refuge in Northampton County.
Component A – Conduct new Phragmites mapping using helicopter-based
GPS technique.
Conduct airborne (helicopter) and ground surveys with GPS position
documentation to provide updated and accurate estimates of Phragmites
distribution on the Eastern Shore Seaside, including re-mapping
of Phragmites on Parramore Island Natural Area Preserve and other
barrier islands in the aftermath of Hurricane Isabel.
Estimated Year 2 budget: $22,000
Component B – Produce refined Phragmites distribution maps
for the Eastern Shore Seaside
In Year 2, draft map products generated in Year 1 will be reviewed
and enhanced using GIS data (e.g. additional data layers) and new
information (from Component A above) added to produce final maps
documenting current Phragmites patch occurrences. These maps will
be used to prioritize control treatments and will also provide an
accurate baseline allowing quantitative comparisons of future Phragmites
distribution to that at present.
Estimated Year 2 budget: $4,000
Component C – Conduct pre-treatment Phragmites monitoring on
Parramore Island necessitated by Hurricane Isabel
The hurricane’s effects on shoreline and vegetation of Parramore
Island were severe enough that some monitoring plots established
in 2003 were obliterated. Work in summer of 2004 will assess these
effects, re-establish plots, and collect data as needed to create
pre-treatment datasets with which Phragmites control treatment effectiveness
will be assessed.
Estimated Year 2 budget: $3,000
Component D – Quantify Phragmites response to wildfire and
hurricane influences at Parramore Island Natural Area Preserve
After extensive field sampling and mapping (including GPS coordinates)
in Year 1, VCU staff will have identified areas where Phragmites
has responded to the 2002 wildfire on Parramore Island. Response
will be assessed based on increased/decreased patch size, as well
as the addition of new patches. However, this Year 1 response data
will provide only a preliminary estimate of the response of Phragmites
to fire. Continued fieldwork is proposed through Year 2 to better
quantify the response and to include measurement of the combined
response to Hurricane Isabel influences. Phragmites patches measured
in Year 1 will be revisited several times each during the successive
two years to monitor patch growth characteristics (i.e. density,
height, total area, % flowering stalks, etc.) and to assess associated
vegetation responses to fire and hurricanes. In Year 2, new Phragmites
patches will be added, mapped, and measured when identified through
periodic surveys throughout the burned area on the Island.
Estimated Year 2 budget: $13,000
Component E – Quantify Phragmites spread at the Eastern Shore
National Wildlife Refuge
In 1995, VCU staff identified Phragmites patches on portions of
the Eastern Shore National Wildlife Refuge (NWR) (Fisherman and
Skidmore Islands). These patches were quantified again in 1996,
one year after aerial spraying with a broad-spectrum herbicide.
At that time, monitoring data suggested that spraying had no significant
effect on Phragmites growth and/or expansion. It is proposed that
these patches be revisited to quantify growth characteristics, etc.
as in Component D above. These data will be compared to 1996 values
to assess rate of spread. New patches will also be identified and
quantified on these two Islands, as well as on the Seaside mainland
portions of the NWR.
Estimated Year 2 budget: $6,000
Federal Funding:
$48,000
Project Contact:
Richard K Myers, (804) 371-6204, rkmyers@dcr.state.va.us
Project Status:
Grant Closed
Final Product Received:
Project Summary Provided by Grantee:
The
objectives of Task 12.08 were (1) to complete a comprehensive aerial
GPS census of Phragmites patch occurrences on the Seaside of the
Virginia Eastern Shore, (2) to produce finished maps depicting the
distribution and abundance of Phragmites on the Seaside, (3) to
conduct post-hurricane monitoring (following Isabel) of Phragmites
on Parramore Island, (4) to assess change in Phragmites distribution
and abundance on Parramore Island following a 2002 wildfire and
a 2003 hurricane, and (5) to assess the 10-year spread of Phragmites
on Fisherman's Island.
Results
1. The aerial GPS census started in July and was completed in September
2004. All patches of Phragmites on the mainland interface, lagoon
system, and barrier islands of the Seaside were located, measured
for extent (area coverage), given a cover class designation, and
mapped using GPS methods. A total of 2,024 acres of Phragmites currently
exists on the Seaside in 1,404 patches. The average patch size is
1.4 acres, with the largest patch covering 186 acres.
2. Information from this census was used to produce an 8-page map
atlas displaying all locations of Phragmites on the Seaside as of
2004. This information will be useful for a variety of purposes,
including planning treatment programs and leveraging funds to support
control treatments. An important application will be to overlay
patches with known occurrences of sensitive resources such as rare
species habitats and communities, in order to prioritize future
Phragmites control programs.
3. Parramore Island monitoring plots were re-located following the
hurricane and re-measured to establish current conditions and allow
post-treatment assessments following application of control measures.
4. Researchers from VCU completed their assessment of wildfire and
hurricane effects on the current Phragmites invasion of Parramore
Island. While it is still too early to measure definitive influences
from the recent hurricane, it is apparent that Phragmites is increasing
within the fire zone of the island. In some locations, there is
strong evidence that the fire has caused rapid Phragmites expansion.
5. VCU scientists re-visited Fisherman's Island 10 years after initial
work with Phragmites there, and found that at least a 5-fold expansion
in area covered by Phragmites has occurred. Currently, 26 hectares
of Phragmites infest Fisherman's. However, future expansion of Phragmites
is likely to be checked by the relatively small amount of remaining
suitable habitat - much of the island may be too low and inundated
with high salinity waters to allow extensive future Phragmites invasion.
Three copies of the final report ("Mapping and Monitoring of
Phragmites on the Seaside of Virginia's Eastern Shore") and
appended map atlas have been provided to the Virginia Coastal Program
(VCP) by DCR-DNH. Shapefiles will be provided to VCP as well, so
that maps can be posted to the DEQ-VCP website.
Form C end
Disclaimer: This project summary provides the federal dollars initially awarded to the grantee. Due to underexpenditure or reprogramming of grant funds, this figure may change. For more information on the allocation of coastal grant funds, please contact Laura McKay, Virginia Coastal Program Manager, at 804.698.4323 or email: Laura.McKay@deq.virginia.gov
A more detailed Scope of Work for this project is available. Please direct your request for a copy to Virginia.Witmer@deq.virginia.gov
