THE RIVER OF
UF Scientists Are Helping To Ensure
That Everglades Restoration Achieves Its Goals BY
UNLESS THE PEOPLE ACT, THE FIRES WILL COME
AGAIN. OVERDRAINAGE WILL GO ON. THE SOIL WILL SHRINK AND BURN AND BE WASTED
AND DESTROYED, IN A CONTINUING RUIN. THE SALT WILL LIE IN WAIT.
MORE THAN HALF A CENTURY AFTER MARJORIE STONEMAN DOUGLAS PENNED THIS DIRE
PREDICTION IN HER CLASSIC 1947 BOOK, THE EVERGLADES: RIVER OF GRASS,
ALL SHE FORESAW AND MORE HAS BEFALLEN THE EVERGLADES. BUT THE PEOPLE
ARE ALSO ACTING.
On December 12, 2000, then-President Bill Clinton
signed a bill authorizing the first stage of a $7.8 billion, 30-year restoration
of the Florida Everglades. Simultaneously, hundreds of scientists were
gathered in Naples, on the Everglades western edge, to discuss ways
to ensure the restoration works.
Science was used as the tool to
sell to the public as well as the Florida Legislature and Congress that
the Comprehensive Everglades Restoration Plan (CERP) would actually work,
conference chairman G. Ronnie Best told scientists assembled for the Greater
Everglades Ecosystem Restoration (GEER) Conference. CERP is strongly
built on science, but CERP is only a blueprint, a concept,
a bunch of good ideas put down on paper. It will require much research
and development to ensure that CERP is implemented and built in such a
way that it will, in fact, work.
Among this largest assembly of scientists
ever gathered to discuss the Everglades were dozens of University of Florida
faculty, students and alumni providing expertise on everything from alligator
habitat to soil chemistry.
One of the leaders of the UF research
effort is Frank Mazzotti, director of the Center for Natural Resources
South Florida and the man responsible for promoting the universitys
role in Everglades research.
UFs Institute of Food and
Agricultural Sciences has a traditional role in making agriculture environmentally
responsible, says Mazzotti. Now IFAS has a new responsibility
to do comprehensive natural resources planning.
In the Everglades, that means defining
the success of the restoration effort.
Science can help us define success,
measure success and ensure that we get the most out of restoration for
the most reasonable cost, says Best, former director of UFs
Center for Wetlands and now chief of the Restoration Ecology Branch of
the USGS Florida Caribbean Science Center. CERP is a dream,
science can make it a reality.
The UF presence at the GEER Conference
was impressive, as much for the breadth of its expertise as for the size
of the contingent.
The University of Florida is definitely
a player, says H. Franklin Percival, courtesy associate professor
of wildlife ecology and conservation and leader of the Florida Cooperative
Fish and Wildlife Research Unit headquartered at UF. Beyond the
obvious associations of the faculty and graduate students making presentations
are many more indirect ones, like people who have gotten their PhDs at
UF and then gone on to positions of influence with state and federal agencies.
Like CERP itself,
UF Everglades research falls into several general categories: water quality
assessment, plant and animal population studies and public policy issues.
In each of these areas, UF faculty and graduate students are engaged in
research to determine the potential impacts, positive and negative, of
the proposed restoration project.
Get The Water Right
Water is the lifeblood of the South Florida ecosystem, according
to CERP, but over the last 70 years water flowing through the Everglades
has been reduced to a third of its historic volume and the quality has
been seriously degraded. So the first goal of the restoration plan is
Get The Water Right.
Ramesh Reddy, graduate research professor and chair of UFs soil
and water science department, likens his teams research in the Everglades
to a doctor diagnosing an illness and suggesting a treatment.
When you get sick, the first thing the doctor does is take your
temperature, then he might do a blood test and then a CAT scan,
Reddy says. Thats a lot like what were doing with the
Everglades. Were looking at the soil and water at progressively
more detailed levels.
Specifically theyre looking at phosphorus, the nutrient many believe
is responsible for cattails driving out sawgrass and algae clogging once-open
water in the Everglades. Unlike carbon and nitrogen, phosphorous is not
easily released back into the atmosphere through chemical and biological
reactions, so it accumulates in soils, in microbes and in vegetation.
For the past 15 years, UF researchers have sampled phosphorous levels
at more than 60 sites throughout Water Conservation Area (WCA) 2A, just
south of the Everglades Agricultural Area. A recent study led by soil
and water science Assistant Professor Bill DeBusk found that the area
of WCA-2A considered phosphorous enriched had increased from
20,829 hectares (48 percent of the total area) in 1990 to 31,777 hectares
(73 percent of the total area) in 1998.
If you compare the water coming in from the agricultural areas with
water quality just about anywhere else in the world, its pretty
clean, Reddy says. But the Everglades ecosystem is so pristine
that just a small spike in phosphorus can cause changes in biological
Reddy says the research results indicate that a phosphorus- enrichment
front is progressing into the relatively unimpacted interior
sawgrass marsh of WCA-2A, bringing with it cattails and other, non-native,
In many areas of the world cattails do a terrific job of helping
to clean up water, he says, but in this ecosystem cattails
are not good. They create an entirely different habitat.
Having taken the ecosystems temperature, Reddy and his
colleagues are now doing the blood test by looking more closely
at the complex relationships among carbon, nitrogen and phosphorus in
the water and soil. Their goal is not only to understand the chemical
processes taking place but to develop techniques that will allow them
to more quickly and easily gather information from a large number of sites.
If you add phosphorus to a phosphorous-limited system, it accumulates
in the plants and the microbes, Reddy says. As those plants
and microbes die and decompose, they not only release phosphorus back
into the system but also release nitrogen, which is really what promotes
To better understand this process, the researchers are growing microbes
collected from WCA-2A in the laboratory and measuring the amount of carbon
dioxide, nitrogen, phosphorus and other chemicals they release.
And the group is preparing to begin the CAT scan through a
new $847,000 grant from the National Science Foundation to conduct molecular-level
research on bacterial communities in the Everglades. Soil and water science
Assistant Professor Andy Ogram is leading this effort to better understand
their genetic makeup and diversity.
The results of this research could provide an early warning system
to disruptions in the ecosystem, Reddy says, and they could
also offer a way of measuring the success of the recovery.
Finally, Reddy says, his group is working to translate the baseline data
they are gathering about the chemical composition of the Everglades ecosystem
into a format that can be incorporated into restoration models.
Were trying to develop a fundamental understanding of whats
happening in the system and then translate that data into a form that
managers can use, Reddy says.
Percival has been studying alligators for 20 years, but only in the last
decade has that research focused on the Everglades, despite the giant
reptiles prominent position in Everglades lore.
You would think that we would know more about an animal with so
much mystique surrounding it, says Percival, but until fairly
recently not much was known about the alligator.
Most of what was known was about alligators in northern Florida, where
commercial farming provided financial incentive to better understand the
living, and breeding, characteristics of the alligator.
Most of the funding sources for alligator research were commercial
farmers, Percival says. You couldnt ranch alligators
in Everglades National Park so there wasnt too much interest in
funding research there.
Even less was known about the American crocodile. Population growth in
southeast Florida had reduced the crocodiles historic habitat to
just a small area of northeastern Florida Bay and northern Key Largo by
all began to change after the two mighty reptiles were protected as endangered
species, the alligator in 1967 and the crocodile in 1975. Interest in
alligator and crocodile research accelerated with plans in the 1990s to
restore the Everglades.
In particular, restoration planners needed real data for the simulation
model known as ATLSS that they were using to test different scenarios.
The Everglades restoration project is arguably the largest experiment
ever undertaken. Typically, scientists conduct an experiment, observe
the results, then report those results. But the complexity and duration
of this project have forced a new, more predictive approach.
Clearly we cannot wait until all the data have been collected, for
instead of gaining the knowledge needed to save the Everglades, we will
have documented its death, Mazzotti says.
Enter ATLSS, the Across Trophic Level System Simulation. Designed to predict
how different water management strategies will impact the Everglades ecosystem,
ATLSS has been adopted by federal, state and tribal authorities as the
primary tool for assessing the ecological effects of different scenarios.
Much of the Everglades research currently under way is aimed at gathering
baseline data about the ecosystem or writing programs to incorporate that
data into ATLSS.
To model the impact different restoration scenarios will have on crocodilians
requires real data about the animals. People like Percival, Mazzotti and
UF alumni Kenneth G. Rice of the U.S. Geological Survey and Laura A. Brandt
of the U.S. Fish and Wildlife Service provide these data that fuel the
ATLSS simulation engine.
The alligator is a top-level predator and its a highly visible
species, politically, Percival says, so when the ATLSS model
was being developed, the alligator was one of the original species included.
Getting data about alligators requires an affinity for top-heavy skiffs
with airplane propellers on the back and waste-deep muck where gators
are one of the lesser threats. Out in this hot, humid natural laboratory,
scientists and graduate students from a host of federal, state and academic
agencies carry out a precision campaign to capture alligators, surgically
implant tracking devices and thermometers and release them back into their
Habitat use and thermoregulation are both closely related to hydrology,
Percival says, adding that the data from tracking and recording the body
temperatures of dozens of alligators over many years indicate that changes
in Everglades water conditions have caused extreme environmental
In addition to their work in the field, Mazzotti, Brandt and Rice are
spending a lot of time in musty, old offices, leading a project to compile
and compare historical data about Everglades alligators into a format
that can be incorporated into ATLSS.
Evaluating long-term trends and developing population models require
a large amount of data collected over many years and many locations,
the trio reported at the Naples conference.
But while information on alligators has been collected in south Florida
since the 1950s, only the most recent is available in a centralized, easily
So, with the help of a legion of graduate students, the researchers have
taken on the Herculean task of compiling yellowing paper, punch cards,
magnetic tape and floppy disks from a host of different federal, state
and local agencies and inputting it into a modern database.
This study allows access to historical data required for ecological
modeling and assessment of current and future status of alligator populations
that would be otherwise inaccessible, the researchers say.
Even as alligator data are being crunched, people like Daniel H. Slone,
a postdoctoral research associate in UFs entomology and nematology
department, are developing ATLSS layers that will be able to employ those
data to estimate alligator populations in the Everglades under different
proposed water management scenarios.
Slone is developing an ATLSS module that employs mathematical equations
to estimate the density of eggs, hatchlings, juveniles and adult alligators
in 500-square-meter tracts of a 3,000-square-kilometer section of the
Everglades. This information is married to maps of land elevation, habitat
types and daily water levels to determine growth, reproduction and survival
Peter Frederick often has a hard time
explaining how he counts wading birds in the Everglades. Ecologists typically
estimate the population of a species in an area by sampling randomly chosen
sections and extrapolating the results to the entire area. But not Frederick.We
count them all, says Frederick, an assistant professor of wildlife
ecology. We have a 100-percent sample.
Over the last 15 years, Frederick, his
graduate students and technicians have logged thousands of hours in a
small plane skimming at 800 feet over a 1,300-square-mile area of the
central Everglades where virtually all of the wading birds congregate,
spotting and photographing the colonies. They also have spent thousands
more hours airboating and wading through shallow, alligator-infested waters
to verify their aerial estimates.
The researchers spend about 2.5 days
per month between January and July conducting aerial surveys and another
two months per year on the ground and in the water. The $250,000 annual
cost is supported by a grant from the U.S. Department of the Interior
through the U.S. Army Corps of Engineers.
The result, Frederick says, is one of the most comprehensive surveys ever
done for any animal living in the Everglades, and one of the most revealing.
The movement of birds from the southwest
coastal region around what is now Naples to the inland water conservation
areas provides some of the most obvious evidence of coastal degradation,
Frederick says, noting that surveys conducted by the Audubon Society in
the 1930s showed virtually all of the wading birds living along the southwest
coast. Today, almost all of the wading birds are in the water conservation
areas because the coastal areas have been almost totally dewatered.
Frederick says his team has found several
ecological surprises during its 15 years studying the Everglades
wading birds some bad and some good.
Up until about two years ago,
our research indicated there were not enough breeding birds in the Everglades
to maintain the populations, Frederick says. There were a
lot more birds just wandering around eating than there were breeding.
Beginning in 1998, however, the researchers
started noticing a dramatic increase in the number of nests, and while
its too early to say for sure if this trend will continue, Frederick
has a hypothesis about the cause that makes him optimistic.
Theres no question that
conditions have been very good over the last two years, he says.
But another possible reason for more birds deciding to breed is
a dramatic drop in mercury levels in the Everglades.
Since 1994, in a study sponsored by
the Florida Department of Environmental Protection, Frederick and several
graduate students have monitored mercury levels in great egret chicks
in the Everglades.
As predators at the top of the food
chain, great egrets are good barometers for the herons, ibises, storks
and spoonbills that also live in the Everglades, Frederick says. Parents
bring food to the nest from within a 15-mile radius, so chicks are ideal
study subjects because the mercury they accumulate comes from the immediate
Because chicks excrete mercury through
their feathers, the researchers are able to harmlessly track the chicks
mercury uptake by plucking a few feathers for analysis.
The results surprised and pleased the researchers. The most significant:
Between 1994 and this year, average mercury levels in the chicks
feathers dropped 73 percent.
The decline overall has been dramatic, and its been occurring
in the face of other environmental changes, such as dry conditions, that
tend to push values up rather than down, Frederick says.
In 1994, the highest concentration of mercury in any of the colonies studied
was 25 parts per million, while the lowest was 5 parts per million. In
2000, the highest concentration was 10 parts per million and the lowest
was 2 parts per million. Normal background levels range from one-half
part per million to 2 parts per million.
The findings bode well for the egrets, which display a variety of ill
effects from mercury poisoning, Fredericks experiments show. At
the average levels seen in 1994, young egrets would have fewer red blood
cells, weigh less and be less interested in hunting.
Chicks can excrete a lot of mercury through their feathers while they
are growing but not when they become adults, so these problems tend to
hit birds just as they reach maturity which also is when they face
the most stressful and dangerous part of their lives, learning to hunt
and avoid predators.
We believe mercury poisoning definitely results in an increase in
mortality, although we dont know how much of an increase,
Mercury in products and industrial processes has been declining since
the late 1980s, when battery manufacturers and others began eliminating
the toxic metal. Also, Florida began imposing mercury-emissions limits
on incinerators in the early 1990s that are just beginning to show results.
Frederick says doctoral candidate Julie Heath has been studying a possible
link between environmental contaminates like mercury and wading bird reproduction.
One of the things that has kept me awake nights is the fear that
we will succeed in restoring the hydrology of the Everglades and the birds
wont respond because theyre so drugged up with mercury,
Frederick says. If we find that these decreasing mercury levels
lead to better reproduction, then it becomes much more likely that wading
birds will be restored to the Everglades if we restore the hydrology.
Back To Science
In a presentation made near the end
of the GEER Conference, Mazzotti returned to the theme Best articulated
in his opening remarks.
science to have an effective voice in environmental policy and decision
making, Mazzotti argues, the following obstacles must be removed:
lack of a comprehensive, regional land and water use plan; lack of a systematic
effort to educate policy and decision makers about scientific knowledge
gained from bioregional assessments; and institutional limitations.
In spite of overwhelming scientific
data about the Everglades, Mazzotti argues, each stakeholder,
including the various federal agencies, state and local governments, is
seeking to control information to benefit its own agenda, not restoration
as a whole.
The inability of institutions participating
in Everglades restoration to escape the limitations of their own agendas
and philosophies may be a formidable barrier to ecological improvement,
Aaron Hoover contributed to this article.
Associate Professor, Department of Wildlife Ecology and Conservation
Frank J. Mazzotti
Director, Center for Natural Resources South Florida
H. Franklin Percival
Courtesy Associate Professor, Department of Wildlife Ecology and Conservation
K. Ramesh Reddy
Graduate Research Professor and Chair, Department of Soil and Water Science
(352) 392-1804 x317
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