Coastal Marsh Management in the western Lake Erie Basin: Perspectives from the Past,
Projections for the Future
Robert J. Gates, School of Environment and Natural Resources, Ohio State University, 2021 Coffey
Road, Columbus, OH, 43210-1085, USA, E-mail: gates.77@osu.edu
Roy W. Kroll, Ducks Unlimited, Inc., Great Lakes/Atlantic Regional Office, 1220 Eisenhower Place,
Ann Arbor, MI 48108, E-mail: rkroll@ducks.org
Extended Abstract: The western Lake Erie marsh
region (Figure 1) lies at a continentally significant
migration pathway for spring- and autumnmigrating waterfowl and other marsh birds. The
coastal marshes that breeding and migrating
waterfowl and marsh birds depend on in this
region are remnants of a vast expanse of forest and
emergent wetlands including the 1,500 km2 “Black
Swamp”. Drainage and conversion of northwest
Ohio’s Black Swamp to intensive agricultural uses
was nearly complete, leaving a fringe of coastal
marshland that is hydrologically affected by daily,
seasonal, and multi-annual variation in water
levels of the western Lake Erie basin (Figure 2).
Historically, coastal marshes migrated inland with
rising water levels, and lake-ward with falling
water levels, in the western Lake Erie basin before
drainage of the black swamp and shoreline
development.
Figure 1. Coastal marshes (numbered dots) are
concentrated in the shallower western basin of
Lake Erie West of Pt. Pelee, ON and Cleveland,
OH. Source: University of Wisconsin
Department of Geology.
The coastal marshes of Lake Erie were initially
protected and many continue to be conserved by
private waterfowl hunting clubs. Some of the
marshes that were protected by private waterfowl
interests have been deeded to local, state, and
federal agencies, including the U.S. Fish and
Wildlife Service and the Ohio Division of
Wildlife.
Figure 2. Mean annual in surface water levels in
Lake Erie, 1918-2005. The line at 173.5
represents low water datum (International Great
Lakes Datum 1983). Source: United States Army
Corps of Engineers, Detroit District.
Impoundments were initially constructed in the
early to mid-20th century to protect coastal
marshes from rising lake levels. Early-constructed
lake levees were largely destroyed by high water
levels in 1950’s and 1970’s but were been
reconstructed, reclaiming 121 km2 of coastal
marshland. The marsh vegetation and waterfowl
communities have undergone profound changes
since the mid 19th century. Vast expanses of wet
prairie, emergent, and submergent vegetation
communities subject to rising and falling lake
levels have been substantially replaced by moist
soil, and Typha spp.-dominated emergent marshes
or flooded croplands where water levels are
regulated by mechanical and gravitational
movement of water through mechanical control
structures. Coincidentally, the waterfowl
community changed from predominantly diving
ducks to mostly dabbling ducks and Canada geese.
Currently, >90% of the remaining coastal marshes
in the Lake Erie basin are impounded to protect
the marshes from fluctuating lake levels because
these marshes are “back-stopped” on the landward
side by agricultural and urban development
pressures which continue to the present. Water
levels of the impounded marshes are typically
managed to promote growth of natural wetland
vegetation and flooded cropland that attracts
autumn-migrating waterfowl, provides habitat for
wetland dependent resident wildlife, and supply
recreational opportunity for hunters and wildlifewatchers.
Water-level management to promote growth of
wetland vegetation within impounded marshes has
introduced a hydro-period that did not correspond
with historic hydrological conditions before
regulation of Great Lakes water levels and
impoundment of marshes and agricultural and
coastal urban development. Nevertheless,
contemporary marsh management has successfully
conserved natural vegetation communities that
support migrating waterfowl and other wildlife.
Although impoundments were demonstrated to
protect coastal mashes from rising lake levels in
the western Lake Erie basin, they have been
criticized as impairing the biodiversity, water
quality, and hydrologic values of these wetlands.
Yet there is evidence that impounded marshes do
perform these ecological functions and values.
The appearance and spread of invasive species,
especially common reed (Phragmites australis),
purple loosestrife (Lythrum salicaria), narrow-leaf
cattail (Typha angustifolia), reed canary grass
(Phalaris arundinacea) and flowering rush
(Butomus umbellatus) have created challenges for
management of coastal marshes in the western
basin. Marsh managers now manage marshes with
longer hydroperiods that promote growth of
persistent emergent and submergent plants,
compared to managing with short hydroperiods
that favor moist soil annuals. Management of
flooded cropland continues mostly because it
appeals to duck hunters, and limits spread of
invasive wetland plant species. Regardless,
flooded cropland provides little benefit to springmigrating waterfowl and detracts from the
biodiversity, water quality, and hydrological
functions and values of coastal marshes. Despite a
general shift from managing flooded cropland and
moist soil vegetation, autumn food resource
availability is high in Lake Erie coastal marshes
and sufficiently high in spring to meet the
energetic needs of spring migrating waterfowl.
Waterfowl hunting success remains high subject
more to hunting pressure, annual variation in
weather conditions and migration chronology than
to food resources availability.
Climate change, continued appearance and spread
of invasive species, coastal development pressure,
biodiversity concerns, multiple use demands will
clearly affect management of the coastal marshes
of Lake Erie in the future. Changing management
paradigms (e.g. managing for spring vs. autumn
resources), economic forces, and demographic
changes in stakeholders and values will present
profound challenges that marsh managers must
adapt to.
We present an historical perspective (Figure 3) on
changes in management of coastal marshes to
provide some insight into how the system will
respond to ecological changes that are coming to
the region, and to the societal pressures that also
determine trajectories and endpoints of change
Lake Erie’s coastal marshes. Although we focus
on the Lake Erie marshes, because they comprise
the largest contiguous area of marshland in the
Great Lakes, our historical perspective and
speculation on the future apply broadly to coastal
marshes throughout the Great Lakes region.
Figure 3. Pre-impoundment reconstruction of
general vegetation distribution on the Winous
Point Shooting Club. Source Gottgens et al. 1998,
Wetlands Ecol. and Manage. 6:5-17.