Protecting U.S. Salt Marshes from the Effects of Global Warming1
Lorna Seitz
Overview
Salt marshes are the most productive ecosystems on earth,2 yet their very survival
is threatened by global warming. The degradation and eventual disappearance of a large
percentage of the world’s salt marshes would precipitate crashes in populations of
commercially harvested fish, shore birds, horseshoe crabs, and numerous endangered
species. Salt marsh loss will also significantly reduce the rate of natural filtration of
pollutants from estuarine waters, either requiring humans to erect additional wastewater
treatment facilities or resulting in closures of mariculture facilities, public shellfishing
grounds, and beaches. Additionally, salt marshes reduce the storm intensity experienced
by coastal communities by dampening wave strength.3 Thus, the destruction or
substantial degradation of salt marshes could cause coastal developments to suffer
1
Due to the different scientific, economic and political challenges facing surrounding the
protection of salt marshes in countries with different legal regimes, topographic features,
and forms of riverine and coastal development, this paper is limited to an examination of
the effects of global warming on U.S. salt marshes. It should be noted, however, that salt
marshes throughout the world are threatened by global warming-induced increases in
annual precipitation, storm intensity and rates of sea level rise. This paper’s focus on the
threats faced by salt marshes in the United States is driven by a desire to find a means to
facilitate the survival of U.S. salt marshes in the face of global warming, and in no way
reflects a conclusion that U.S. salt marshes face greater jeopardy, or are more important
than, salt marshes in other nations.
2
“Salt Marsh Productivity,” National Oceanic and Atmospheric Administration (2000)
(See: http://www.csc.noaa.gov/otter/htmls/ecosys/ecology/smprod.htm).
3
Dr. Elizabeth Wenner, Dynamics of the Salt Marsh, S. Carolina, An
Information/Education Series from the Marine Resources Division, South Carolina
Department of Natural Resources.
(See http://water.dnr.state.sc.us/marine/pub/seascience/dynamic.html)
1
increased damages as a result of medium and high intensity storms. The loss of salt
marshes would constitute an enormous economic, ecological and aesthetic loss to society.
This paper identifies coastal and riverine developments as factors that can
significantly diminish, or utterly preclude, a salt marsh’s ability to adapt to global
warming. Bulkheads preclude salt marshes from migrating to higher ground in response
to sea level rise, riverine levees decrease the rate of sediment deposition in salt marshes
and jetties increase erosion rates in undeveloped, and unprotected, areas. This paper
concludes by identifying various legal and financial mechanisms capable of protecting
the ability of salt marshes to migrate and trap sufficient sediment to support a sufficient
vertical growth rate to accommodate for global sea level rise. The legal mechanisms
available for protecting salt marshes include:
•
legislatively establishing that a rolling public easement exists over intertidal
lands;
•
exercising eminent domain over areas into which salt marshes will likely
migrate during the next hundred years, and transforming these areas into
National Estuarine Research Reserves, Wildlife Sanctuaries, or parks;
•
privatizing fishing rights, and using the funds raised from selling these rights
to purchase sufficient estuarine habitat to serve as nurseries and breeding
grounds for the allocated fish;
•
selling developmentally restricted lands including and abutting salt marshes to
pharmaceutical companies for sustainable horseshoe crab harvesting;
2
•
defunding the National Flood Insurance Program, and allowing the high cost
of private flood insurance hinder further floodplain development and rebuilding;
•
prohibiting the Army Corps of Engineers from erecting additional flood
control levees along U.S. rivers, and prohibiting the Corps from spending
additional funds to maintain existing levees, thereby allowing rivers to reclaim
their historic courses and ending another governmental means of subsidizing
flood plain development; and
•
zoning coastal areas for Planned Unit Developments, allowing increased
development density in exchange for either increased coastal setbacks or
decreased total coastal acreage developed.
Purchases of coastal lands and development rights are the primary financial mechanisms
through which U.S. salt marshes can be assisted in surviving global warming.
Though the use of various combinations of the above legal and financial tools is
necessary to enable salt marshes to survive global warming, these tools may not, alone,
be sufficient to facilitate salt marsh survival. More research is needed to discover whether
or not salt marshes are capable of migrating to upland areas at rates which will equal, or
outpace, the anticipated rates of sea level rise in the next century. In areas where the rate
of sea level rise is anticipated to be particularly high, humans may need to facilitate rapid
salt marsh migration by acting to encourage the rapid peat development in, and
colonization of, upland areas. National Estuarine Research Reserve scientists, community
groups, and schools should design and carry out experiments to see what actions can be
taken to facilitate the rate of marsh migration.
3
If all of the above steps are taken, global warming related salt marsh losses can be
kept to a minimum. It is vitally important that we act now to halt further land uses that
would threaten the long term viability of salt marshes. Once a parcel of land has been
developed, it can become inordinately expensive for either the government or an
environmental non-profit to remove the problematic structure. Actions to preserve salt
marshes must occur before the rate of sea level rise accelerates further, and coastal
property owners begin to panic about how to preserve their properties from coastal
flooding. It is also imperative that we act immediately to reduce greenhouse gas
emissions so that the rate of global warming does not further increase. A discussion of
methods of reducing green house gas emissions is, however, beyond this paper’s scope.
Salt Marshes
Salt marshes are transitional areas between land and water exhibiting biota
capable of surviving in this high salinity, intermittently flooded, environment. Salt
marshes are found along the intertidal shores of estuaries and sounds. A marsh is
classified as a salt marsh so long as the salinity of the interstitial waters exceeds that of
fresh water. As the sea level rises, salt marshes increasingly extend into the mouths of
rivers, as well as into upland areas.
4
The plants found in salt marshes differ from those found in fresh water marshes
because they are specially adapted to life in a saline environment. In order to prevent
dehydration through osmosis, some salt water marsh plants concentrate salts in their
roots.4 This causes the plant’s salinity to exceed that of the surrounding interstitial water,
allowing water to be drawn into the plant’s roots, rather than from them. Other salt marsh
plants cope with the high salinity conditions by excreting salt from pores along their
stems.5 Marsh plants also need strong roots, so they will not be dislodged from the
ground either during regular tidal fluctuations or during more severe storm episodes,6 and
they need to be capable of surviving prolonged periods of root exposure.7 The
4
“Arcata Marsh Wildlife Sanctuary, Saltwater Vegetation,” Humboldt State University
(2000). (See: http://www.humboldt.edu/~ere_dept/marsh/saltveg.html).
5
Id.
6
Id.
7
“Coastal Salt Marshes,” California Environmental Resources Evaluation System,
California Resources Agency (1994).
(See: http://ceres.ca.gov/ceres/calweb/coastal/plants/smarsh.html)
5
distribution of marsh plants reflects each species’ salinity, tidal flux, and UV tolerance
thresholds.8
Global sea level has been rising for centuries.9 However, the rate of sea level rise
is anticipated to increase as a result of increased rates of global warming10 and polar ice
cap melt.11 Though salt marshes have proven capable of migrating to higher ground and
further up river deltas in response to sea level rise thus far, it is unclear whether or not
salt marshes are capable of migrating at the pace necessitated by an increased rate of sea
level rise.12 If salt marsh species are incapable of colonizing upland areas as the salinity
and tidal flux conditions in these areas come within their tolerance ranges, the total area
colonized by salt marsh species will decline. Species that cannot migrate upland at the
same rate as the sea will become swamped, their UV and salinity tolerances exceeded,
and they may be incapable of surviving.
8
Dr. Elizabeth Wenner, Dynamics of the Salt Marsh, S. Carolina, An
Information/Education Series from the Marine Resources Division, South Carolina
Department of Natural Resources.
(See http://water.dnr.state.sc.us/marine/pub/seascience/dynamic.html)
9
See Appendix A
10
“Key Strategic Issues Concerning Coastal Areas and Climate Change,” 1998 Year of
the Ocean, Impacts of Global Climate Change with Emphasis on U.S. Coastal Areas.
(See: http://www.yoto98.noaa.gov/yoto/meeting/climate_316.html)
11
Id.
12
The White House Committee on the Environment and Natural Resources (CENR) is
currently compiling research data which may establish the limits of salt-marsh ability to
adapt to sea-level rise by migrating to upland areas.
1998 Year of the Ocean, Impacts of Global Climate Change with Emphasis on U.S.
Coastal Areas, at G-34.
(See: http://www.yoto98.noaa.gov/yoto/meeting/climate_316.html)
6
The Value of Salt Marshes
Ensuring the long term survival of large, healthy, and productive salt marshes is
of critical local, regional, and international importance. Salt marshes provide valuable
ecosystemic, waste water treatment and flood control services. Salt marshes also serve as
homes to numerous species; some of which are endangered, of high commercial value,
and of high value to medical researchers. The significance of salt marshes to nearby
communities cannot be underestimated. In many coastal communities, salt marshes are at
the center of local cultural and community life. What would Maine be without lobster,
Louisiana without shrimp or Cape Cod without clams? In all of these regions, species
which rely on salt marshes during all or part of their life cycle are widely collected and
consumed, and serve as the basis for countless festivals, on a local basis.
Salt marshes are necessary to sustain the commercial viability of the coastal
fisheries upon which many coastal communities rely. 70% of commercial fish depend
upon salt marshes for all or part of their lives.13 The total take of U.S. commercial
fisheries in 1999 was more than 4.2 metric tons, or more than $3.5 billion worth of fish.14
If 70% of the total value of U.S. commercial fishing is salt marsh reliant, salt marshes
contributed approx. $ 2.45 billion dollars to the U.S. GDP in fish alone in 1999.
Endangered species of fish, and endangered birds reliant upon fish as food sources, also
rely upon coastal salt marshes.15
13
“Salt Marshes: A Critical Narragansett Bay Habitat, Save the Bay (2000)
(See: http://www.savebay.org/habitat/Saltmarsh.htm).
14
“Fisheries of the United States,” Fisheries Statistics & Economics, National Marine
Fisheries Service, National Oceanic and Atmospheric Administration (October, 23 2000).
(See: http://www.st.nmfs.gov/st1/fus/fus99/index.html).
15
See Appendix A for a partial list of Endangered and Threatened animals found in
National Estuarine Research Reserves containing salt marshes.
7
As global warming progresses, the habitats birds currently rely on during
migration may cease to be sufficient to meet their needs. Declines in migratory bird
populations will adversely affect the interests of bird watchers, hunters and
environmentalists throughout the birds’ range. Failure to adequately protect migratory
birds, and their habitat, will also cause the U.S. to violate its treaty obligations to
Canada.16
Spotlight Species: The Horseshoe Crab
Research based on the Horseshoe Crab has served as the basis for 3 Nobel Prizes.17
The most recent Nobel Prize was awarded for insights into human vision and cognitive
processing gained through experimentation on Horseshoe Crabs. The medical profession
uses an extract from the horseshoe crab's blue, copper-based blood called to test the
purity of medicines. This product, limulus amoebocyte lysate (LAL), is important in
detecting e-coli contamination in medicines.18 There is no substitute for LAL. The
horseshoe crab’s shell has been used to speed blood clotting and to make absorbable
sutures.19 Horseshoe crabs have also been harvested for use as bait and dried for use as
fertilizer and poultry food supplements.20
Horseshoe crabs are also important to the healthy functioning of the salt water
16
The Migratory Bird Treaty Act of 1918 (16 U.S.C. 701 et seq.).
(See: http://www4.law.cornell.edu/uscode/16/ch7.html).
17
Alex Hawes, “Crabs in the Crossfire,” ZooGoer 28(3) 1999.
(See: http://www.fonz.org/zoogoer/zg1999/28(3)crab2.htm).
18
John Henkel, “Drugs of the Deep,” U.S. Food and Drug Administration (1998).
(See: http://www.fda.gov/fdac/features/1998/198_deep.html)
19
John Henkel, “Drugs of the Deep,” U.S. Food and Drug Administration (1998).
(See: http://www.fda.gov/fdac/features/1998/198_deep.html)
20
“Horseshoe Crab, Living Fossil,” National Aquarium in Baltimore (1997)
(See: http://www.aqua.org/animals/species/prhcrab.html).
8
marshes within which they are found. The eggs of horseshoe crabs are important sources
of food for migratory shore birds.21 Fish also eat the juveniles or recent molts.22 Due to
historic over-harvesting for bait, and their importance as the sole source of LAL, there are
currently harvest restrictions for horseshoe crabs along the mid and northern Atlantic
coast of the U.S.23
Horseshoe Crabs
http://ael.er.usgs.gov/groups/stats/Limulus/
21
Id.
http://www.beach-net.com/horseshoe/Bayhorsecrab.html.
23
“Horseshoe Crab Conservation,” ABC News Associated Press (February 29, 2000)
(See: http://abcnews.go.com/sections/science/DailyNews/horseshoecrabs000229.html);
“Fishery Threatens Horseshoe Crabs, Shorebirds,” CNN (October 2, 1998)
(See: http://www.cnn.com/TECH/science/9810/02/crabs.yoto).
22
9
Threats to Salt Marshes
Though this paper is primarily focusing on the effects of sea level rise on salt
marsh health and migration, global warming is also affecting salt marshes by altering the
geographic distribution, timing, and intensity of rain and snow fall.24 Global warming
results in the melting of polar ice caps, and results in a corresponding increase in the
percentage of the earth’s surface that is covered by ocean. By increasing the percentage
of the earth covered by ocean, and continuing to increase global temperatures,
evaporation rates also increase. Higher evaporation rates lead to increased precipitation.
As the rate of global climate change increases, riverine, as well as coastal, flood
severity will increase.25 Increased rainfall in the Mississippi River watershed, for
example, would increase the frequency and intensity of flooding along the Mississippi
and it’s tributaries. Increased incidences of severe flooding will increase pressures to
build additional levees along U.S. rivers to protect property from the destructive effects
of flooding. In fact, increased incidences of flooding along the Mississippi are already
increasing pressures to build new levees, and to increase the height of existing ones.26
The erection of levees along the Mississippi and it’s tributaries threatens
downstream marshlands because the levees divert the Mississippi from flooding
downstream estuaries on a regular basis. Channeling the Mississippi River prevents water
24
“Key Strategic Issues Concerning Coastal Areas and Climate Change,” 1998 Year of
the Ocean, Impacts of Global Climate Change with Emphasis on U.S. Coastal Areas.
(See: http://www.yoto98.noaa.gov/yoto/meeting/climate_316.html)
25
Robert Watson, Marufu Zinyowera & Richard Moss (Eds.), The Regional Impacts of
Climate Change: An assessment of vulnerability, A Special Report of IPCC Working
Group II, Published for the Intergovernmental Panel on Climate Change (Nov. 1997).
(See: http://www.ipcc.ch/pub/sr97.htm#overview).
26
Douglas Jehl, “Mississippi Floods Revive Debate on What Government Should Do,”
The New York Times, A1, A16 (April 27, 2001).
10
from flowing over areas which would otherwise constitute wetlands, increases in-stream
flow rates and water volume, and reduces the area on which sediment deposition can
occur. By reducing the rate of sediment deposition in Mississippi delta estuaries, these
estuaries may have become incapable of naturally increasing elevation to compensate for
sea level rise.27
If additional levees are erected, other coastal marshes may suffer a fate similar to
that of estuaries in the Mississippi River Delta: namely, their rates of land-subsidence
relative to sea level may be accelerated beyond the rates envisioned by current modeling
efforts. Current sea-level rise models fail to account for the possibility that rates of
sediment deposition in marshes may decrease due to the erection of additional upstream
levees.
Increasing the levee system along U.S. rivers amounts to a subsidy to developers
who wish to build in the river bed. The market itself should prevent people from
developing in the floodplain. It is often prohibitively expensive, or impossible, to
purchase private flood insurance to cover developments in frequently and severely
flooded areas. Were federally-subsidized flood insurance and federal disaster assistance
unavailable, private developers might find it uneconomic to build, or to rebuild, in the
floodplain. The federal government can, at no expense to itself, virtually prevent further
development of frequently flooded areas by discontinuing federal flood insurance
programs, and federal disaster relief areas where flooding was substantially foreseeable.
Furthermore, the Army Corps of Engineers can substantially reduce the incidence of
27
“Key Strategic Issues Concerning Coastal Areas and Climate Change,” 1998 Year of
the Ocean, Impacts of Global Climate Change with Emphasis on U.S. Coastal Areas.
(See: http://www.yoto98.noaa.gov/yoto/meeting/climate_316.html)
11
riverine levees by curtailing further levee building and maintenance efforts.
Bulkheads & Rolling Public Easements
The implementation of coastal-protection measures to protect developed land
from the adverse effects of sea level rise could increase the rates of salt marsh loss along
the Pacific and Atlantic coasts significantly beyond current estimates. Bulkheads are a
common method of protecting coastal property from erosion and storm damage.
Bulkheads prohibit salt marshes from migrating to upland areas by covering the land that
the marsh would otherwise migrate over, or to, with a hard, impermeable surface such as
concrete.
As coastal build up and sea level rise both continue, pressures to erect bulkheads to
protect private property from the incursion of the sea will mount. These bulkheads will
12
undoubtedly be constructed to protect developed land, thus deflecting the tidal energy
towards the undeveloped, and unprotected, estuaries upon which many species of fish and
birds rely.28
The erection of jetties could also constitute a significant threat to estuarine
habitat, as jetties are commonly used to protect developed areas and community beaches,
displacing marine sediment from unprotected areas into ones just up current of the
jetties.29 Efforts to protect human property from sea level rise, increasing storm severity
and increasing erosion rates will necessitate that undeveloped coastal areas
disproportionately bare the environmental stresses caused by global warming and sea
level rise.
The construction of new bulkheads and jetties can be prohibited either if the
proposed barrier is found to constitute a nuisance or if the proposed barrier encroaches
upon land to which either the federal or state government holds pre-existing use-rights. In
states where there is a recognized right of public access to the intertidal zone for
subsistence and/or recreational fishing, claming, seashell collection or recreational
enjoyment, this right could result from either the public trust doctrine,30 a statue or deed
28
“Flood Control and Shoreline Protection,” Army Corps of Engineers
(See: http://www.sad.usace.army.mil/floodcon.htm).
29
Texas Coastwide Erosion Response Plan, Texas General Land Office (2 July 1999).
(See: http://www.glo.state.tx.us/coastal/cerp/part1.html).
30
The most common form of governmentally held servitude over private coastal lands is
based in the public trust doctrine. The public trust doctrine recognizes that certain natural
resources are must be held in common for the public good. The application of the public
trust doctrine to the intertidal zone recognizes the public’s right to continue using the
intertidal zone in the manner which pre-dated the division and sale of beachfront land. In
many jurisdictions, the public did not relinquish its rights to use intertidal lands when
specific individuals were granted permission to build on the abutting upland property.
Applying the public trust doctrine to protect salt marshes would protect the public’s
historic, and continuing, interests in these areas.
13
restrictions applicable to all beachfront properties.
Though individuals who own coastal property have an interest in protecting their
homes, private property owners should not be able to claim full use rights to lands held in
public trust by erecting bulkheads which prevent the upland migration of inter-tidal
habitats. The migration of salt marshes (and mudflats) should, like erosion, be viewed as
a risk associated with owning coastal property. In areas prone to erosion, or facing
relative sea level rise, coastal property owners should realize that their lot sizes will
diminish as a result of natural forces, and that they have no right to infringe upon historic
use rights, or to increase erosion rates on their neighbor’s land, by erecting barriers to
prevent natural erosion and marsh migration from occurring.
In states where there are no laws currently on the books which make explicit the
existence of a rolling public easement over coastal lands,31 such laws need to be passed
so homeowners , buyers and developers will understand their development and use rights.
The existence of rolling public easements also needs to be clarified to help coastal zone
planners, zoning boards and the Army Corps of Engineers understand the extent to which
they can restrict further coastal development without needing to compensate land owners
for “taking” their property. Establishing the existence of rolling public easements over
intertidal lands should be the highest priority in protecting coastal salt marshes, because
each time the existence of a rolling public easement over intertidal lands is
determinatively established, there will be some protection against further development of
coastal areas throughout the entire state. Furthermore, as a rolling public easement would
31
Rolling Public Easements often allow people to build in coastal areas, but require that
all structures built are removed when threatened by an advancing shore line.
(See: “Global Warming – Coastal Zones,” U.S. Environmental Protection Agency.
http://www.epa.gov/globalwarming/impacts/coastal.index.html.)
14
be based, in large part, upon the public trust doctrine, all citizens should have the right
obtain judicial review of decisions by zoning authorities or by the Army Corps of
Engineers to allow any development in the intertidal zone, including the development of
bulkheads and jetties.
Conservation Easements - Purchased
In states which reject the rolling public easement idea, it is important to organize
coastal communities behind initiatives to purchase development rights for lands onto
which salt marshes will be likely to migrate within the next 100 years. In states where
rolling public easements have been rejected, local community groups and national
environmental non-profits should be approached as sources of funding for purchasing
development rights. When local community groups are educated as to the value of salt
marshes to their local economies, they will likely become interested in ensuring that
healthy salt marshes exist well into the future. Thus, members of the community who
collect shellfish, engage in recreational or commercial fishing or birding, operate
tourism-dependant businesses, run marine aquaculture facilities, and/or swim in coastal
waters should be educated as to how salt marshes protect their economic and recreational
interests. Members of national land trusts can educate members of the local communities
as to the value of acting quickly to protect salt marshes, and can advise them on how to
go about purchasing development rights and conservation easements over coastal lands.32
32
See Appendix C
15
Conservation Easements, Voluntary
Owners of land abutting salt marshes often purchased the property due to a love
of the marsh’s beauty. Once knowledgeable of the threats which further development of
their property might pose to the marsh’s future survival, abutting land owners might
willingly restrict their future property development by donating a conservation easement
over their land to a local or national land trust. Individuals owning land near marshes
could be further encouraged to encumber their land with conservation easements if the
existence of a conservation easement were to reduce the taxes assessed on the property.
Reducing the taxes imposed on developmentally-encumbered land reasonably reflects the
property’s diminished re-sell value.
Current Efforts at Marsh Preservation – The National Estuarine Research Reserve System
The National Estuarine Research Reserve System protects a total of more than
one million acres of estuarine habitat divided between twenty-five different reserves in
the United States.33 The reserves are used as centers for estuarine research and education.
Community and regional groups are encouraged to participate with NERR scientists in
developing plans to protect the reserves from the adverse effects of off-site land use
activities. The NERRS also centrally compiles data on changes in water depth,
temperature, salinity, dissolved oxygen, turbidity, pH, and biota in the various reserves.34
The reserves may someday provide information on the ability of salt marshes to adapt to
33
Theresa Shearer, National Estuarine Research Reserve System, National Oceanic and
Atmospheric Administration (April 29, 2001). (See: http://www.ocrm.nos.noaa.gov/nerr).
34
Theresa Shearer, “System-wide Monitoring Program,” National Estuarine Research
Reserve System, National Oceanic and Atmospheric Administration (April 29, 2001).
(See: http://www.ocrm.nos.noaa.gov/nerr/monsys.html).
16
sea level rise and reduced sedimentation rates which proves vital to developing coastal
management plans which ensure future salt marsh survival. Monitoring of the NERRs
can reveal the effects of land-use and climate changes on salt marshes.35 To date, the
scope of NERR research has been severely limited by funding constraints, and there are
no significant funding increases visible on the horizon. The future success of the NERRs
in identifying how to protect salt marshes from the adverse effects of global warming
may well be contingent upon the ability of NERR staff to enlist the assistance of welltrained community members to engage in marsh monitoring activities on a volunteer
basis.
35
http://www.ocrm.nos.noaa.gov/nerr/monsys.html
17
The National Estuarine Research Reserve system represents an important step in
protecting America’s salt marshes. However, though the NERRs provide some fish and
bird habitat, they are merely habitat islands in a sea of development. These reserves,
standing alone, cannot provide the same quantity of salt marsh habitat that existed before
coastal development, or that exists today. Not only is the rate of coastal development
increasing, but so is our national appetite for fish. As consumer demand for fish
increases, the commercial value of salt marshes as breeding grounds for marine fisheries,
will continue to increase. Good economics suggests that salt marshes should be protected
for their highest sustainable use, and that is for use as fish habitat. The National Estuarine
Research Reserves, though a step in the right direction, do not provide sufficient habitat
to support the trillions of pounds of fish which Americans consume annually. These
reserves were envisioned as areas for research and community education, not as sufficient
estuarine protection in their own right. If the U.S. commercial fisheries are to regain
economic viability, not only do all currently functional salt marshes need to be preserved,
but historic salt marshes must also be restored and areas of probable future marsh
migration need to remain undeveloped.
Conclusion
Salt marshes perform invaluable and irreplaceable ecosystemic services. Their
preservation should be a high priority for all environmentalists, land use planners,
fishermen, fish consumers, bird lovers and coastal residents. Salt marshes will be
swamped, their plants dying out as salinity and UV tolerances are exceeded, unless the
marshes either are protected from sea level rise or are able to migrate to upland areas at a
18
rate which exceeds the rate of sea level rise. Since sea level rise is unavoidable, we need
to take actions now to increase the chances that salt marsh plants will be capable of
migrating to upland areas. The first step which must be taken is that the areas surrounding
current salt marshes need to remain undeveloped, as the development of these areas
would absolutely prevent marsh migration. Possible means of protecting upland areas
from development include:
•
enacting laws which explicitly state there is a rolling public easement over the
intertidal zone,
•
purchasing development rights over coastal lands,
•
offering discounted tax rates to land owners who sell or donate to a
conservation trust the right to develop coastal lands, and
•
encouraging governmental entities to purchase additional land for NERRs and
natural coastal parks.
The protection of upland areas, though necessary to protect the ability of salt marshes to
adapt to sea level rise, may not, on its own, be sufficient to protect salt marshes. In
addition to protecting upland areas to allow marsh migration, stream flows must be
protected in order to ensure that rates of sediment deposition are sufficient to enable
vertical marsh growth at rates equal to, or exceeding, sea level rise. At a minimum, new
levees should not be erected to control flooding in upstream areas. Additionally, the
social, ecological and economic importance of salt marshes necessitates that marsh
restoration efforts be undertaken. Many of these efforts will require that fill, earthen
19
seawalls, and exotic plants be removed.36 Historic stream flows should also, where
possible, be restored to provide an adequate rate of sediment deposition.
Galvanizing the public to act to preserve salt marshes requires, first and foremost,
education. People who rely on salt marshes for their very survival need to understand the
extent of their reliance upon these highly productive areas and they need to gain a sense
of their duty to protect salt marshes. The NERR’s focus on community education is a step
in the right direction. All salt marshes near inhabited areas should serve as classrooms for
educating school children, neighbors and community groups about what salt marshes are,
how they function, and what ecosystemic, ecological and economic services they provide.
Community members should be involved in monitoring salt marshes, and the data which
they collect should be added to the NERR’s national data base. There is still insufficient
understanding of the species that inhabit the various salt marsh regions, the salinity
tolerances of various plants, and the upland migration rates of salt marshes. The NERRs
currently lack sufficient funding or personnel to conduct all of the experiments which
they have planned. Training and meaningful use of community members in species
identification, biodiversity surveying, and marsh restoration efforts may be necessary if
the NERRs are to understand salt marsh ecology in time to save the marshes from the
adverse effects of global warming.
Immediate action to prevent further development within the future coastal and
riverine floodplains, in combination with increased research into techniques for assisting
the rates of marsh migration, should be able to keep global-warming induced salt marsh
36
See The Essex Elementary and Middle School’s Salt Marsh web page at:
http://www.tiac.net/users/essex/marsh/saltmarsh.html.
20
losses to a minimum. Given the economic, cultural and ecological importance of salt
marshes, it is imperative that we act quickly to ensure that salt marshes can persevere
well into the future.
21
Appendix A
See: Environmental Defense Fund website (http://www.edf.org/programs/GRAP/y3k).
22
Appendix B
Endangered and Threatened Species Found in
National Estuarine Research Reserves
Birds
Light-footed clapper rail
California Least Tern
Belding’s Savannah Sparrow
Least Bell’s Vireo
California Brown Pelican
Florida Scrub Jay
Peregrine Falcon
Wood Stork
Snowy Plover
Piping Plover
Wilson’s Plover
Least Tern
Bald Eagle
Southern Bald Eagle
Osprey
Tijuana River Reserve
Tijuana river, Elkhorn
Tijuana River
Tijuana River
Tijuana River, Elkhorn, South Slough
Rookery Bay
Tijuana River, Elkhorn, South Slough, Mt. Vernon, Wells,
Mullica River, Chesapeake Bay, N. Carolina, Sapelo Island,
Rookery Bay
Rookery Bay
Tijuana River
Wells, Waquoit Bay, Mullica River, N. Carolina
Sapelo Island
Wells, Waquoit Bay, Rookery Bay
South Slough, Wells, Great Bay, Mullica River,
Chesapeake Bay, N. Carolina, Weeks Bay, Rookery
Bay
Sapelo Island
Great Bay – NH, Sapelo Island
Rookery Bay: 20 birds listed as endangered, threatened, or of special concern by FL fish and game
Fish
Cutthroat Trout
Coho Salmon
Gulf Sturgeon
Alabama Shovelnose Sturgon
South Slough
South Slough, Mt. Vernon
Weeks Bay
Weeks Bay
Plants
Salt Marsh Bird’s Beak
Wild Cotton
Golden Leather Fern
Inkberry
Bay Cedar
Curtiss’ Milkweed
Pineweed
Giant Leather Fern
Tijuana river
Rookery Bay
Rookery Bay
Rookery Bay
Rookery Bay
Rookery Bay
Rookery Bay
Rookery Bay
23
Prickley Pear Cactus
Spike Moss
Sandplain Gerardia
Swamp Pink
Knieskern’s Beaked-Rush
Sensitive Joint-Vetch
Seabeach Amaranth
American Chaffseed
Smooth Tick Trefoil
Downy Bushclover
Threadlaid Naiad
Downy Milk Pea
Rynchosia
Red Turtlehead
Bushy Rockrose
Thread-Leaved Sundew
Butterfly-weed
Little Ladies Tresses
Eastern Lilaeopsis
Vetchling
Narrow-Leaved Wild Rice
Knotroot Foxtail
Rookery Bay
Rookery Bay
Waquoit Bay
Mullica River
Mullica River
Mullica River
Mullica River
Mullica River
Chesapeake Bay
Chesapeake Bay
Chesapeake Bay
Chesapeake Bay
Chesapeake Bay
Chesapeake Bay
Waquoit Bay
Waquoit Bay
Waquoit Bay
Waquoit Bay
Waquoit Bay
Waquoit Bay
Waquoit Bay
Waquoit Bay
Rookery Bay: More than 100 of the Basin’s 1500 plant species are listed as either endangered or
threatened.
Turtles
Loggerhead Turtles
Alabama Red-Bellied Turtle
Alligator Snapping Turtle
Alligator Map Turtle
Atlantic Ridley
Kemp’s Ridley Sea turtle
Green Turtle
Leatherback
N. Carolina, Sapelo Island, Apalachicola Bay, Rookery Bay
Weeks Bay
Weeks Bay
Weeks Bay
Apalachicola Bay
Rookery Bay
Apalachicola Bay
Apalachicola Bay
Snakes
Gulf Salt Marsh Snake
Eastern Indigo Snake
Indigo Snake
Black Pine Snake
Florida Pine Snake
Weeks Bay
Weeks Bay, Apalachicola Bay
Rookery Bay
Weeks Bay
Weeks Bay
24
Appendix C
A Guide to Community-Based Salt Marsh Protection
Identifying the Stakeholders
The first step in initiating a community-based salt marsh protection project is
identifying the stakeholders. Those who concretely benefit from the salt marsh should,
once educated, desire to take actions to facilitate the marsh’s future survival. Which
individuals fish (either commercially or recreationally), own or work for seafood-related
businesses (such as packing facilities and restaurants), participate in marsh-related
activities (like bird watching or canoeing) or rely on high estuarine and coastal water
quality either to draw tourists to the region or for personal recreational access?37
Mariculturists, scientists, youth groups,38 educators and environmentalists should also be
included in marsh preservation efforts. Owners of property abutting threatened salt
marshes must be included in any marsh preservation effort. Failure to include abutting
and near-by land owners in all stages of marsh preservation planning will greatly increase
the likelihood that property owners will organize a coalition opposing the salt marsh
preservation effort. State, regional and local coastal zone and land-use planners also need
37
Though a decline in salt marsh cover or health could forseeably harm public health by
diminishing water quality, this link is still somewhat speculative. Since many of the
individuals who should be interested in marsh preservation have competing economic
interests in protecting private property from the adverse effects of sea-level rise, it is
probably wise at this point to highlight the irrefutable harms which will result from salt
marsh destruction.
38
Youth groups benefit from marshes due to the recreational and educational
opportunities available in marshes and the future dependence which individual members
of the group will have on the marshes. Efforts at environmental protection should always
attempt to form partnerships with youth groups due to their boundless energy, need for
leadership and educational opportunities, and parental influence.
25
to be involved in designing marsh preservation plans, and may be able to provide
technical, legal and financial assistance to the marsh preservation effort.
Educating the Stakeholders & Getting them Involved
The stakeholders can be educated by presentations to community groups,
professional associations, schools, religious groups and services clubs. Tours of the
marsh can also be organized, either for educational or for recreational purposes. Bird
watching and other low-impact activities, such as canoeing and kayaking, should be
encouraged in estuarine areas. Stakeholders must gain an active involvement the salt
marsh area so that preservation issues do not become “out of sight, out of mind.” The
marsh needs to become a visible, and integral, part of people’s daily lives. Increases of
recreational and educational opportunities within the marsh itself are important first steps,
which should be rapidly followed by creating opportunities for those using the marsh to
take actions to monitor, restore and/or take legal action to protect the marsh.
Technical Advice
Since marsh monitoring and restoration efforts require scientific expertise, the
local community will need to secure scientific assistance in designing and implementing
marsh monitoring and restoration plans. Local universities, NERR sites and
environmental organizations are good sources of scientific assistance and oversight.
The services of a lawyer will be necessary if it becomes apparent that legal
measures might be needed to protect the marsh. Those seeking to preserve a salt marsh
may be able to associate with an existing land trust, or environmental nonprofit, in order
26
to obtain attorney assistance at no cost. If existing land trusts and environmental nonprofits are incapable of providing free legal services, a local attorney in private practice
may be willing to provide pro-bono assistance to protect existing legal rights and to
propose and negotiate the terms of conservation easements.
Identifying Available Funding
Existing land trusts, such as the Trust for Public Lands, should be approached for
funding, and/or funding advice. In addition, governmental agencies, such as the U.S.
Environmental Protection Agency, the National Oceanic and Atmospheric
Administration and state Environmental Protection Agencies, often provide funding for a
salt marsh education, monitoring, and restoration initiatives. These agencies usually offer
grants to community groups with viable projects to preserve and protect marsh habitats.
Federal environmental agencies also maintain lists of other private and public
organizations which fund habitat protection and restoration projects. The leading
philanthropic organization concerned with environmental protection operative in the U.S.
is the Pew Charitable Trust. The Pew Foundation offers funding to universities and
established non-profits working to protect the marine environment. Members of the local
community, including fisheries trade organizations and corporations whose activities lead
to marsh degradation, should also be approached as possible sources of funding for
community-based marsh preservation, restoration and community education initiatives.39
39
Funding for community-based marsh monitoring, education and restoration efforts is
currently available from the following organizations: The U.S. Environmental Protection
Agency’s Estuary Restoration Grants Program (http://www.epa.gov/owow/estuaries),
National Oceanic and Atmospheric Administration’s Community Based Restoration
Project (http://www.nmfs.noaa.gov/habitat/restoration), Coastal America
27
Opportunities for Long-term Community Involvement
An excellent example of community-based monitoring of a salt water marsh is
provided by the students at Essex Elementary and Middle School.40 The students at Essex
Elementary monitored the interstitial salinity of a salt marsh at differing zones and depths
and identified and recorded the plants and animals spotted by students. Students from
Essex Elementary reported their findings to the Massachusetts Audubon Society. Not
satisfied with merely monitoring a salt marsh, the Essex students proceeded to identify
the factors leading to the salt marsh’s degradation and to design a marsh remediation
plan. As remediation was conducted, the Essex students continued to monitor the effects
of remediation.
Though the salt marsh monitored by students from Essex Elementary was being
impacted by water flow restrictions and exotic species, rather from the adverse affects of
global climate change, it provides an excellent model of the actions which community
members can take to protect their natural environment. The Essex project exemplifies the
fact that community members, even the youngest ones with the least scientific
background, are capable of conducting important marsh monitoring duties with proper
training and supervision. The Essex project demonstrates that involvement of individuals
living near NERRS, or whose property abuts current salt marsh habitat, can provide
valuable services to help identify salt marsh migration rates. Community monitoring of
(http://www.coastalamerica.gov), Pew Charitable Trusts (http://www.pewtrusts.com),
and the Curtis and Edith Munson Foundation. For further information, see the America’s
Estuaries web site at: http://www.estuaries.org.
40
The Essex Elementary and Middle School’s Salt Marsh web page is located at:
http://www.tiac.net/users/essex/marsh/saltmarsh.html.
28
salt marshes can also help researchers improve their understanding of the abundance,
zonation and interactions of marsh species.
Coordination with Other Land Trusts, Research Projects and the NERRS
Salt marsh data collected through community monitoring and experimentation
must be standardized, as much as possible, and centrally compiled and interpreted.
Though several different governmental and non-profit organizations are currently
compiling salt marsh data, it would make sense to have community groups coordinate
their monitoring efforts with scientists in the National Estuarine Research Reserve
System. The NERRS already maintains a centralized database which compiles and
analyzes data collected system-wide. It would be relatively simple for the NERRS to add
data collected by community groups from privately held, or unprotected, marsh lands into
its database. Participation in a national monitoring effort would provide individuals with
a reason for continuing monitoring efforts, and involvement with marsh preservation, in
the long term.
29
References
International
The Migratory Bird Treaty Act of 1918 (16 U.S.C. 701 et seq.).
http://www4.law.cornell.edu/uscode/16/ch7.html
Robert Watson, Marufu Zinyowera & Richard Moss (Eds.), The Regional Impacts
of Climate Change: An assessment of vulnerability, A Special Report of IPCC
Working Group II, Published for the Intergovernmental Panel on Climate Change
(Nov. 1997). http://www.ipcc.ch/pub/sr97.htm#overview
Federal Government – Army Corps of Engineers
Flood Control and Shoreline Protection, Army Corps of Engineers.
http://www.sad.usace.army.mil/floodcon.htm
Federal Government – Environmental Protection Agency
Estuary Restoration Grants Program, U.S. Environmental Protection Agency.
http://www.epa.gov/owow/estuaries
Global Warming – Coastal Zones, U.S. Environmental Protection Agency.
http://www.epa.gov/globalwarming/impacts/coastal.index.html.)
Federal Government – Food and Drug Administration
John Henkel, Drugs of the Deep, U.S. Food and Drug Administration (1998).
http://www.fda.gov/fdac/features/1998/198_deep.html
Federal Government – National Oceanic and Atmospheric Administration
Community Based Restoration Project, National Oceanic and Atmospheric
Administration. http://www.nmfs.noaa.gov/habitat/restoration
Fisheries of the United States, Fisheries Statistics & Economics, National Marine
Fisheries Service, National Oceanic and Atmospheric Administration
(October, 23 2000). http://www.st.nmfs.gov/st1/fus/fus99/index.html
1998 Year of the Ocean, Impacts of Global Climate Change with Emphasis on
U.S. Coastal Areas. http://www.yoto98.noaa.gov/yoto/meeting/climate_316.html
Salt Marsh Productivity, National Oceanic and Atmospheric Administration
(2000). http://www.csc.noaa.gov/otter/htmls/ecosys/ecology/smprod.htm
Theresa Shearer, National Estuarine Research Reserve System, National Oceanic
and Atmospheric Administration (April 29, 2001).
http://www.ocrm.nos.noaa.gov/nerr
30
State Government
Coastal Salt Marshes, California Environmental Resources Evaluation System,
California Resources Agency (1994).
http://ceres.ca.gov/ceres/calweb/coastal/plants/smarsh.html
Dynamics of the Salt Marsh, S. Carolina, An Information/Education Series from
the Marine Resources Division, South Carolina Department of Natural Resources.
http://water.dnr.state.sc.us/marine/pub/seascience/dynamic.html
Texas Coastwide Erosion Response Plan, Texas General Land Office
(2 July 1999). http://www.glo.state.tx.us/coastal/cerp/part1.html
Educational Institutions
Arcata Marsh Wildlife Sanctuary, Saltwater Vegetation, Humboldt State
University (2000). http://www.humboldt.edu/~ere_dept/marsh/saltveg.html
The Essex Elementary and Middle School’s Salt Marsh web page
http://www.tiac.net/users/essex/marsh/saltmarsh.html
Non-Profits
America’s Estuaries web site: http://www.estuaries.org.
Environmental Defense Fund website: http://www.edf.org/programs/GRAP/y3k
Salt Marshes: A Critical Narragansett Bay Habitat, Save the Bay (2000).
http://www.savebay.org/habitat/Saltmarsh.htm
News Publications
Fishery Threatens Horseshoe Crabs, Shorebirds, CNN (October 2, 1998)
http://www.cnn.com/TECH/science/9810/02/crabs.yoto
Horseshoe Crab Conservation, ABC News Associated Press (February 29, 2000)
http://abcnews.go.com/sections/science/DailyNews/horseshoecrabs000229.html
Mississippi Floods Revive Debate on What Government Should Do, The New
York Times, A1, A16 (April 27, 2001).
Zoos & Aquariums
Crabs in the Crossfire, ZooGoer 28(3) 1999.
http://www.fonz.org/zoogoer/zg1999/28(3)crab2.htm
Horseshoe Crab, Living Fossil, National Aquarium in Baltimore (1997)
http://www.aqua.org/animals/species/prhcrab.html
31