Site by Bennett Web & Design Co.
2010 SOUTHEASTERN NATURALIST 9(3):477–486
Submersed Aquatic Vegetation of the Jean Lafitte National
Historical Park and Preserve
Michael A. Poirrier1,*, Kathy Burt-Utley1, John F. Utley1,
and Elizabeth A. Spalding1
Abstract - The Barataria Preserve unit of Jean Lafitte National Historical Park and
Preserve is located in wetlands of the upper Barataria-Terrebonne estuary near New
Orleans, LA and subject to perturbations that affect aquatic resources. A study of
submersed aquatic vegetation (SAV) was conducted to determine community composition,
distribution, and abundance. Seven native species—Cabomba caroliniana,
Ceratophyllum demersum, Heteranthera dubia, Najas guadalupensis, Potamogeton
pusillus, Vallisneria americana, and Zannichellia palustris—and three exotic
species—Egeria densa, Hydrilla verticillata, and Myriophyllum spicatum—were
present. The highly invasive, exotic, floating fern Salvinia molesta was also present.
The Preserve is affected by a coastal restoration project designed to return Mississippi
River flow to the upper Barataria Estuary. Preserve SAV did not conform to the
general estuarine management paradigm of decline and loss with nutrient introductions.
Instead, freshwater dominated the Preserve, and sufficient light was present
to support robust SAV growth in ponds, canals, and Lake Cataouatche. Native and
exotic species formed large surface mats that clogged waterways. Vallisneria americana
may be decreasing due to the increase in nuisance SAV and floating plants.
This study is the first of its kind for any wetland habitat in the states of the Northern
Gulf Coast and therefore will be an important baseline to future studies both
generally and specifically for the Preserve as Louisiana’s coastal wetland waterways
experience change brought on by the general coastal wetland loss from sea level rise
and efforts to restore the wetlands.
Submersed aquatic vegetation (SAV) refers to rooted, vascular, flowering
plants that live and grow below the water surface (Cronk and Fennessy 2001).
These submersed macrophytes perform a multitude of ecological functions
including providing habitat and food for estuarine animals, decreasing wave
energy, increasing sedimentation, and stabilizing sediments (Cronk and
Fennessy 2001, Hemminga and Duarte 2000, Ward et al. 1984). SAV is very
sensitive to slight changes in salinity, turbidity, and nutrient levels, and its
distribution and abundance are good indicators of subtidal environmental
quality (Davis and Brinson 1980, Dennison et al. 1993). Loss of SAV can
have direct effects on fish and wildlife resources and estuarine landscape
dynamics. Despite the ecological importance of SAV, little is known about
community composition or environmental factors that control SAV distribution
and abundance in coastal Louisiana. A study of submersed aquatic
1Department of Biological Sciences, University of New Orleans, 2000 Lakeshore
Drive, New Orleans, LA 70148. *Corresponding author - email@example.com.
478 Southeastern Naturalist Vol. 9, No. 3
vegetation in the Barataria Preserve of Jean Lafitte National Historical Park
and Preserve (JELA; henceforth the Preserve) was conducted to provide information
on community composition, distribution, and abundance (Poirrier
et al. 2009). The need to protect representative natural communities in the
Preserve was identified in the Resource Management Plan (JELA 1997).
The 7446- hectare Preserve is in the northeast portion of the 0.6 millionha
Barataria-Terrebonne estuarine system, approximately 15 km south of
New Orleans in Jefferson Parish, LA (Fig.1). Waters within the Preserve
generally range from fresh to slightly brackish (Swarzenski et al. 2004).
Sources of brackish water include Bayou Barataria and Lakes Salvador and
Cataouatche. Sources of freshwater include local rainfall, drainage from
wetlands, agricultural land, and urban areas, and a coastal restoration diversion.
Since 2002, Mississippi River water enters northern Lake Cataouatche
during openings of the Davis Pond Diversion. It is capable of transferring
10,650 cubic feet/second (cfs) of water from the Mississippi River into waterways
adjacent to the Preserve (USACE 2000). Flow from the diversion
occurs during high-water periods in the River during the first half of the year,
and a minimum flow of about 1000 cfs is maintained year-round. Nutrients
are generally present in these freshwater sources causing a north–south gradient
of decreasing nutrient levels along the Bayou Segnette Waterway and
shorelines of Lake Cataouatche and Salvador.
In coastal Louisiana, salinity is the primary factor controlling SAV community
structure, and light intensity at suitable depths determines abundance
(Cho and Poirrier 2005). A diverse SAV community occurs in freshwater, and
some freshwater species extend into low-salinity brackish water (3–5 ppt),
but at salinities ranging from 5 to 20 ppt, only Myriophyllum spicatum L.
(Eurasian Water-milfoil) and Ruppia maritima L. (Widgeon-grass) occur
(Hester et al. 2005, Stutzenbaker 1999). Salinity tolerance is affected by
rate of salinity change, nutrients, and available light. Plants can generally
tolerate higher salinities when values are stable and other conditions are
optimum for maintenance and growth (French and Moore 2003). Submersed
aquatics have true roots that absorb nutrients from sediment, which allows
them to grow in nutrient-poor waters. However, with eutrophication, SAV
is generally replaced by algae due to overgrowth of epiphytes on SAV and
dense phytoplankton which shade SAV (Harlin 1995). The minimal depth
that SAV can occur is controlled by low-water events that expose plants to
lethal drying and damaging waves (Cho and Poirrier 2005). Wave energy in
shallow water can also uproot plants and suspend sediments, which increase
turbidity to levels that limit growth. Maximum depth of SAV occurrence is
controlled by decreasing light with increasing depth.
Previous general vegetation surveys conducted in the Preserve included
White et al. (1983), Michot (1984), Michot and Doyle (1999), Swarzenski
et al. (2004), and Nolfo-Clements (2006). These studies focused on marsh
habitats, and most did not cover the entire Preserve. The following SAV
species were reported: Cabomba caroliniana A. Gray (Fanwort, Carolina
2010 M.A. Poirrier, K. Burt-Utley, J.F. Utley, and E.A. Spalding 479
Fanwort); Ceratophyllum demersum L. (Coontail, Coon’s tail, Hornwort);
Heteranthera dubia (Jacq.) MacM. (Water Star-grass, Grassleaf Mud
Plaintain); Hydrilla verticillata (L.f.) Royle (Water Thyme); Myriophyllum
spicatum; Najas guadalupensis (Spreng.) Magnus (Common Water Nymph,
Southern Water Nymph); and Vallisneria americana Michx. (Water-celery,
Tape-grass, Freshwater Eel Grass, American Eel Grass).
Perturbations to the Preserve include habitat degradation from urban
development, exotic species, marsh management, and oil and gas mining
(JELA 1997). There is also concern about possible effects of the Davis
Pond Mississippi River Diversion. While generally considered a solution
to wetland loss, this diversion could harm SAV. Increases in nutrient levels
and turbidity due to suspended silts, clays and phytoplankton can decrease
light available for photosynthesis, increase the growth of algal epiphytes
on SAV leaves, and restrict SAV growth. Invasive non-native SAV may become
established under these conditions. The objectives of this study were
to determine: the relative abundance and distribution of native, exotic, and
nuisance SAV; the habitats where they occur; and factors associated with
their distribution and abundance.
Aquatic habitats throughout the Preserve were surveyed from June 2006
through April 2008. Methods included observations of surface growth from
a boat and raking the bottom to locate vegetation not visible at the surface.
Lakes, canals, bayous, and ponds were sampled from a shallow draft boat with
a garden rake. Marsh and swamp sites accessible by air boat and boardwalks
were also examined. Familiar species were identified and photographed in the
field. Unfamiliar species were identified in the laboratory. Representative
specimens of each species were examined in the laboratory, and voucher
specimens prepared. Nomenclature followed the Integrated Taxonomic Information
System (USDA 2009). Voucher specimens were deposited in The
University of Southern Mississippi herbarium.
The ecological importance of the species within communities of underwater
plants is generally not easy to quantify, especially from surface
observations in the diverse types of habitats within an ecosystem such as
that of the Preserve. Estimation of coverage over bottom plots was impossible.
Quantification was made using relative abundance of each species
based mainly upon proportion of presence/absence at the sites, i.e., rank
order. We also estimated the size of rooted beds of canopy-forming species
and included this information in our ranking. Data were obtained from 146
representative sites (Fig. 1), a large number of sites across all habitats in the
Preserve. Our rank order values generally agreed with site abundance and
distribution in the Preserve.
We measured the maximum depth at which SAV occurred, photosynthetically
active radiation, and Secchi disc transparency to obtain information on
how light reduction with depth affected SAV abundance. Salinity (ppt) was also
480 Southeastern Naturalist Vol. 9, No. 3
determined using a YSI 85 S-C-T, DO meter. Secchi disc transparency (ft) and
depth (ft) were determined using a weighted Secchi disc. Photosynthetically
active radiation was measured with a Li-Cor quantum sensor and photometer.
Results and Discussion
Seven native species were found—Cabomba caroliniana; Ceratophyllum
demersum; Heteranthera dubia; Najas guadalupensis; Potamogeton
pusillus L. (Baby Pondweed, Small Pondweed); Vallisneria americana;
and Zannichellia palustris L. (Horned Pondweed)—as well as three exotic
species—Egeria densa Planch. (Waterweed, Brazillian Elodea); Hydrilla
verticillata; and Myriophyllum spicatum. These ten species are regarded as
true SAV because they are rooted and have leaves that are always submersed.
Three species that are similar to true SAV were also present: Myriophyllum
aquaticum (Vell.) Verdc. (Parrot-feather), an exotic species with emergent
leaves; Potamogeton epihydrus Rafinesque (Ribbon-leaf Pondweed), a native
species with floating leaves; and Utricularia cf. radiata Small (Little
Floating Bladderwort), a native, floating species. The presence of the exotic
floating fern, Salvinia molesta D.S. Mitchell (Giant Salvinia) was also
Figure 1. Map of the Jean Lafitte National Historical Park and Preserve showing its
location in Louisiana and the 146 study sites.
2010 M.A. Poirrier, K. Burt-Utley, J.F. Utley, and E.A. Spalding 481
documented. This is the first record of Egeria densa, Potamogetom pusillus,
Zannichelia palustris, and Salvinia molesta from the Preserve.
Submersed vegetation was found in man-made canals, ponds, bayous,
and estuarine lakes. True SAV is sensitive to desiccation and was absent
from marshes and swamps because these shallow habitats are exposed to
periodic drying. The distribution of different SAV species was directly influenced
by salinity and the indirect effect of salinity reducing floating aquatics
that shade SAV. Information about the distribution and ecology of individual
species is summarized in Table 1 and further discussed in order of abundance
below. General information about species was compiled from Godfrey and
Wooten (1979, 1981), Flora of North America Editorial Committee (1993),
and Stutzenbaker (1999).
Ceratophyllum demersum, a native species, was found at 78 sites
throughout the Preserve and occurred with all other SAV species found in
this study and was previously reported in the Preserve. It lacks true roots,
but has modified leaf branches that serve as anchoring “rhizoids”. Persistent
growth produces large vegetative mats that are anchored to the bottom and
cover quiet waters. However, plants are easily dislodged from the bottom
and drift with currents. It is regarded as a freshwater species but was common
in quiet tidal water at salinities ranging from 0.2 to 0.7 ppt.
Najas guadalupensis is a native species and was found at 63 sites and
ranked 2nd in relative SAV abundance. It occurred throughout and was previously
reported in the Preserve. Although it is regarded as a freshwater
species, it is known to tolerate stable salinities up to 3.5 ppt.
Myriophyllum spicatum is a native of Europe, Asia, and North Africa
that has rapidly spread throughout the US. It was found at 30 sites, ranked
3rd in relative SAV abundance, and was previously reported in the Preserve.
It was more abundant in Bayou Segnette and waters west of Bayou Segnette
Table 1. Summary of information on the submersed aquatic plants (SAV) of Jean Lafitte National
Historical Park and Preserve including new species occurrence records, non-native and native
species, relative abundance based on rank order of occurrence at study sites, species intolerant
of salinity levels above 0.5 ppt (freshwater species), species tolerant of salinity levels 0.5 to 3.5
ppt (not salinity-limited), and species which form large nuisance canopies.
record Rank Fresh- Not
from Non- order of water salinity Forms large
Species Preserve native occurrence species limited canopies
Cabomba caroliniana 8 X
Ceratophyllum demersum 1 X X
Egeria densa X X 9 X
Heteranthera dubia 7 X
Hydrilla verticulata X 4 X X
Myriophyllum spicatum X 3 X X
Najas guadalupensis 2 X X
Potamogeton pusillus X 6 X
Vallisneria americana 5 X
Zannichellia palustrius X 10 X
482 Southeastern Naturalist Vol. 9, No. 3
than canals in the interior of the Preserve. It is generally regarded as an invasive,
nuisance species because of excessive growth that displaces native
vegetation and adversely affects habitat quality. However, it appears to have
become naturalized and provides habitat for fish and invertebrates and food
for waterfowl. It was found at salinities ranging from 0.2 to 0.5 ppt, and is
known to tolerate stable salinities as high as 20 ppt.
Hydrilla verticillata is native to Asia, Africa, and Australia. It has become
established in the southeastern United States including Louisiana. It was
found at 25 sites and ranked 4th in relative SAV abundance and was previously
reported in the Preserve. It is generally regarded as a highly invasive species
that can reproduce by fragments, stolons, seeds, turions, and tubers, but does
provide habitat for invertebrates and fish, and its turions and tubers provide
food for water fowl. It was more abundant in the northwestern areas of the
Preserve. Competition from the more abundant species listed above may have
restricted its growth. We found it in salinities ranging from 0.2–0.6 ppt, but it
is known to tolerate periods of increased salinity up to about 10 ppt.
Vallisneria americana is a native species that occurs in fresh and brackish
water habitats in southeastern Louisiana and was previously reported in the
Preserve. It was found at 20 sites and ranked 5th in relative SAV abundance.
It occurred in the Pipeline Canal between the Waterway and the Lower Kenta
Canal, but was more abundant in lower Bayou Segnette from north of Bayou
Villars to the Tarpaper Canal, where it was replaced by canopy-forming species
and filamentous alga. It also occurred in protected areas along the shore
of Bayou Bardeaux. Plants 1.7 m long were present in Lake Cataouatche.
In the past, this large growth form was regarded as a separate species,
V. neotropicalis. A concern is the possible reduction of V. americana from
competition from more abundant mat-forming SAV, filamentous algae, and
floating plants. The leaves of V. americana are tape or ribbon-like and it is
well rooted. Unlike bushy species, V. americana does not form large surface
mats. It appears to be more abundant where wave energy from wind, boat
traffic, and tidal exchange limit the growth of other SAV. It provides habitat
for invertebrates and fish and food for water fowl. Vegetative propagation is
by buds from in-bottom rhizomes. New growth is from the base of the leaves
which are more susceptible to shading after winter die-back or damage. We
found it at salinities ranging from 0.3 to 0.5 ppt, but it grows well at salinities
up to 5 ppt.
Potamogeton pusillus is a native species that is common in fresh and
slightly brackish waters in southeastern Louisiana. This is the first report
of this species from the Preserve. It was found at 18 sites and ranked 6th in
relative SAV abundance. It was found at salinities ranging from 0.2–0.7 ppt,
but it is known to occur at salinities up to 3.5 ppt. It was more abundant in
the interior canals. Although widespread, it does not form nuisance mats
and is an important waterfowl forage plant. It appears to be an opportunistic
species that is more abundant in late winter and early spring and decreases
during the summer and fall.
2010 M.A. Poirrier, K. Burt-Utley, J.F. Utley, and E.A. Spalding 483
Heteranthera dubia occurs throughout North America and is a native
species that has been previously reported in the Preserve. We found it at 14
sites, and it ranked 7th in relative SAV abundance. It was found at salinities
ranging from 0.2 to 0.6 ppt, but has been reported at salinities up to 3.5 ppt.
Although some large beds occurred in Lake Cataouatche, it did not occur at
nuisance levels in the Preserve. It provides habitat for fish, invertebrates, and
waterfowl and currently does not present a management concern.
Cabomba caroliniana is a native freshwater species that occurs in eastern
and central US. It is common in southeastern Louisiana and was previously
reported in the Preserve. It was found at 13 interior sites east of Bayou
Segnette and ranked 8th in relative SAV abundance. We found it at sites that
had a salinity range of 0.3–0.4 ppt. It appears to be limited by salinities
greater than 0.5 ppt. This restriction may explain its absence from western
and southern areas of the Preserve. It did not produce large, nuisance colonies.
Although it provides habitat for aquatic animals, it is not regarded as a
food source for wildlife.
Egeria densa is a South American native that has become widely naturalized
in waters that include the Gulf States, but has not previously been
reported in the Preserve. It was found at 4 sites and ranked 9th in relative
SAV abundance. We found it at salinities ranging from 0.3 to 0.4 ppt. It
was found in interior canals and ponds. Since it does not occur at salinities
greater than 0.5, salinity tolerance appears to restrict its distribution. Dispersal
is by plant fragmentation.
Zannichellia palustris is a native species that occurs in fresh and tidal
freshwaters in southeastern Louisiana. This is the first record of this species
from the Preserve. We found it at one site in the interior of the preserve, and
it ranked 10th in relative SAV abundance. Little is known about its ecology,
but it is known to tolerate brackish water. Unpublished observations by Poirrier
from other sites in southeastern Louisiana indicate that it behaves as an
annual species with growth in late winter and spring and die-back during
summer. This seasonal occurrence and competition from species that persist
throughout the year may explain its limited distribution.
Many species were abundant at nuisance levels. With the exception of
V. americana, Preserve SAV was generally dominated by species with nearsurface
terminal growth, which formed large surface mats that clogged
waterways. This growth often included plants which were suspended near the
water surface, but were not rooted. These thick mats were usually composed of
C. demersum, N. guadalupensis, H. verticillata, M. spicatum, floating aquatics,
and filamentous algae. These species did not dieback during winter due to
the mild climate and protected waters of the Preserve. New spring growth continued
from near-surface vegetation. In contrast, P. pusillus and Z. palustris
behaved as annual species. In south Louisiana, they are generally present in
late winter and spring, producing seeds and dying back during summer.
The minimum depths of SAV occurrence ranged from near zero in protected
interior canals and ponds, where abundant SAV generally extended
484 Southeastern Naturalist Vol. 9, No. 3
to the shoreline, to between 0.3 to 0.45 m in the lower Bayou Segnette Waterway,
Lake Cataouatche, and Bayou Bardeaux, where wave energy from
wind and boats in addition to higher water-level fluctuation contributed to
near-shoreline stress. The minimum depths present in the Preserve are lower
than those in estuarine water closer to the coast where stronger tides produce
greater water-level fluctuations.
Light availability was generally not a limiting factor for SAV growth in
shallow canals and ponds where Secchi disc transparencies ranged from 0.4
to 1.2 m. Light did limit SAV growth to depths of 0.3 to 0.9 m on both banks
of the Bayou Segnette Waterway, with Secchi disc transparencies ranging
from 0.5 to 0.6 m. SAV did not occur at sites in upper Bayou Segnette and
lower Bayou Barataria where Secchi disc visibilities were below 0.3 m. SAV
was abundant in Lake Cataouatche and included H. dubia, N. guadalupensis,
H. verticellata, M. spicatum, C. demersum, V. americana and P. pusillus. SAV
was present at depths ranging from 0.3 to 1.7 m in Lake Cataouatche, and Secchi
disc visibility there ranged from 0.3 m to being visible on the bottom at
1.7 m. SAV was absent from depths of 1.8 to 2.1 m in Lake Cataouatche.
National Park Service staff and other local observers confirm that SAV
abundance increased in Lake Cataouatche, Bayou Villars, and, in some
years, northeastern Lake Salvador, as the operation of Davis Pond became
more regular and volume increased from 2002 to the beginning of this study.
The estuarine and marine management paradigm of SAV loss with nutrient
introduction generally does not apply to freshwater submersed aquatics
where nuisance growth often occurs with nutrient increases. The lowering
of salinity to freshwater or near-freshwater levels and the movement of water
through Davis Pond removing dissolved inorganic nutrients and binding
them to particles which settle into the sediment are probable explanations for
this increase. Freshwater ecosystems also support a diverse SAV community
and numerous insect and amphibian epiphyte grazers that probably control
algal overgrowth on SAV. Submersed vascular plants can out-compete algae
when available nutrients are bound to sediments because they have true roots
that can use sediment nutrients. Once established, SAV can decrease wave
energy and increase water clarity to make habitats more suitable to persistent
SAV growth. Invasive exotics may also promote SAV colonization and
habitat modification to maintain SAV communities.
Numerous floating plants occur in quiet Preserve canals and ponds
(Nolfo-Clements 2006). They cover the water surface and through shading
affect SAV abundance, distribution, and community structure. We found
Salvinia molesta at 10 sites. This is the first record of this species from
the Preserve. It is recognized as a noxious aquatic weed and listed on the
Federal noxious weed list (USDA 2006). Based on studies by Divakaran
et al. (1980), the USDA listed S. molesta as a “strictly” freshwater species.
However, the lowest salinity level tested in their study was 7 ppt, which
retarded growth and damaged plant tissue but did not result in mortality.
Salvinia molesta was found in and around the lower Pipeline Canal and
2010 M.A. Poirrier, K. Burt-Utley, J.F. Utley, and E.A. Spalding 485
Bayou Segnette Waterway. Salinity ranged from 0.4 to 0.6 ppt and 1.2 ppt
in nearby Lake Salvador, well below levels damaging to S. molesta. Unlike
most other floating aquatics that are stressed by brackish water, S. molesta
is not salinity-limited in the Preserve.
In conclusion, the Preserve supports a diverse SAV community, and
the Davis Pond Diversion seems to be increasing SAV abundance in most
of the Preserve. Filamentous algae and native and exotic floating aquatics
are also increasing but shade true SAV. This increased production could be
regarded as a stage in wetland plant restoration or considered an unwanted
shift in habitat type that interferes with recreational fishing and boating.
A major concern is the spread of Salvinia molesta throughout the Preserve
and the potential damage to SAV and general habitat quality for fish and
wildlife. Vallisneria americana may be decreasing due to competition from
floating aquatics and nuisance SAV.
This study was funded by the National Park Service, US Department of the Interior,
PMIS #3862. We thank the following individuals who assisted in this study:
Nancy Walters, David Muth, Whitney Granger, and Kathy Lang of the National Park
Service, Carol Franze and Ashley Walker of the Estuarine Research Lab, and Maureen
Cho, H.J., and M.A. Poirrier. 2005. A model to estimate potential SAV (submersed
aquatic vegetation) habitat based on studies in Lake Pontchartrain. Restoration
Cronk, J.K., and M.S. Fennessy. 2001. Wetland Plants: Biology and Ecology. CRC
Press LLC, Boca Raton, fl. 462 pp.
Davis, G.J., and M.M. Brinson. 1980. Responses of submersed vascular plant communities
to environmental change. US Fish and Wildlife Service, Kearneysville,
WV. FWS/OBS-79/33. 70 pp.
Dennison, W.C., R.J. Orth, K.A. Moore, J.C. Stevenson, V. Carter, S. Kollar, P.W.
Bergstrom, and R. Batiuk. 1993. Assessing water quality with submersed aquatic
vegetation. Bioscience 43:86–91.
Divarkan, O., M. Arunachalam, and N.B. Nair. 1980. Growth rates of Salvinia molesta
Mitchell with special reference to salinity. Proceedings of the Indian Academy
of Science (Plant Science) 89:161–168.
Flora of North America Committee. 1993. Flora of North America North of Mexico.
Flora of North America, New York, NY.
French, G.T., and K.A. Moore. 2003. Interactive effects of light and salinity stress on
the growth, reproduction, and photosynthetic capabilities of Vallisneria americana
(Wild Celery). Estuaries 26:1255–1268.
Godfrey, R.K., and J.W. Wooten. 1979. Aquatic and Wetland Plants of the Southeastern
United States: Monocotyledons. University of Georgia Press, Athens,
GA. 712 pp.
Godfrey, R.K., and J.W. Wooten. 1981. Aquatic and Wetland Plants of the Southeastern
United States: Dicotyledons. University of Georgia Press, Athens, GA.
486 Southeastern Naturalist Vol. 9, No. 3
Harlin, M.M. 1995. Changes in major plant groups following nutrient enrichment.
Pp. 173–188, In A.J. McComb (Ed.). Eutrophic Shallow Estuaries and Lagoons.
CRC Press, Boca Raton, fl.
Hemminga, M.A., and C.M. Duarte. 2000. Seagrass Ecology. Cambridge University
Press, Cambridge, England, UK. 298 pp.
Hester, M.W., E.A. Spalding, and C.D. Franze. 2005. Biological Resources of the
Louisiana Coast: Part 1. An overview of coastal plant communities of the Louisiana
gulf shoreline. Journal of Coastal Research Special Issue No. 44:146–161.
JELA. 1997. Jean Lafitte National Historical Park and Preserve Resource Management
Plan. Jean Lafitte National Historical Park and Preserve, New Orleans, LA.
Michot, T.C. 1984. A marsh vegetation study of Jean Lafitte National Historical Park.
US Fish and Wildlife Service, Lafayette, LA. 25 pp.
Michot, T.C., and T.W. Doyle. 1999. Composition and change in marsh vegetation
from transects at Jean Lafitte National Historical Park and Preserve, Barataria
Unit in 1983 and 1993. Jean Lafitte National Historical Park and Preserve Natural
Resources Symposium. Lafayette, LA.
Nolfo-Clements, L.E. 2006. Vegetative survey of wetland habitats at Jean Lafitte
National Historical Park and Preserve in southeastern Louisiana. Southeastern
Poirrier, M.A., K. Burt-Utley, J.F. Utley, and E.A. Spalding. 2009. An Inventory and
Assessment of the Distribution of Submersed Aquatic Vegetation at Jean Lafitte
National Historical Park and Preserve. University of New Orleans, New Orleans,
LA. PMIS #3862. 57 pp. Available online at http://science.nature.nps.gov/im/
bmersedAquaticVegetationatJELA.pdf. Accessed 2009.
Stutzenbaker, C.D. 1999. Aquatic and Wetland Plants of the Western Gulf Coast.
Texas Parks and Wildlife Press, Austin, TX. 465 pp.
Swarzenski, C.M., S.V. Mize, B.A. Thompson, and G.W. Peterson. 2004. Fish and
aquatic invertebrate communities in waterways, and contaminants in fish, at the
Barataria Preserve of Jean Lafitte National Historical Park and Preserve, Louisiana,
1999–2000. US Geological Service, Baton Rouge, LA. 35 pp.
US Army Corps of Engineers (USACE). 2000. Davis Pond Freshwater Diversion
Project. Available online at http://www.mvn.usace.army.mil/pao/brochures.htm.
US Department of Agriculture (USDA). 2006. Plant protection and quarantine. Federal
noxious weed list (24 May 2006). USDA Animal and Plant Health Inspection
Service, Washington, DC. 2 pp.
USDA. 2009. Integrated Taxonomic Information System (ITIS). Available online at
http://www.itis.usda.gov. Accessed 2009.
Ward, L., W.M. Kemp, and W.R. Boynton. 1984. The influence of waves and seagrass
communities on suspended sediment dynamics in an estuarine embayment.
Marine Geology 59:85–103.
White, D.A., S.P. Darwin, and L.B. Thien. 1983. Plants and plant communities of
Jean Lafitte National Historical Park, Louisiana. Tulane Studies in Zoology and