Science-based habitat restoration...
 Minimum flows and fish resourc...
 Adaptive management of native fisheries...
 Florida ecosystems in the...

Group Title: Waterworks
Title: Waterworks. April 2007.
Full Citation
Permanent Link: http://ufdc.ufl.edu/UF00067314/00015
 Material Information
Title: Waterworks. April 2007.
Series Title: Waterworks
Physical Description: Serial
Language: English
Creator: Institute of Food and Agricultural Sciences
Publisher: Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida
Publication Date: April 2007
 Record Information
Bibliographic ID: UF00067314
Volume ID: VID00015
Source Institution: University of Florida
Rights Management: All rights reserved by the source institution and holding location.


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Table of Contents
    Science-based habitat restoration in lakes
        Page 1
    Minimum flows and fish resources
        Page 2
    Adaptive management of native fisheries in the Grand Canyon
        Page 3
    Florida ecosystems in the spotlight
        Page 4
Full Text


.4 OF

Newsletter of the UF/IFAS Department of Fisheries and Aquatic Sciences April 2007

Ecosystem responses to habitat
restoration are being evaluated
in Big Gant Lake. This collaborative
research project is being conducted
by Drs. Mike Allen (FAS) and Wiley
Kitchens (Department of Wildlife
Ecology and Conservation and
Florida Cooperative Fish and Wildlife
Research Unit), with funding from the
Florida Fish and Wildlife Conservation
Commission (FWC).

The Situation

Channelization and flood control
alter hydrology and create perhaps
the largest anthropogenic impact
to Florida's freshwater ecosystems.
Historically, water levels in Floridalakes
fluctuated substantially in response to
variations in rainfall across seasons,
years and decades. Channelization
stabilized water levels in many lakes,
so that levels now fluctuate nearly
independent of rainfall amounts.
Stable water levels foster dense stands
of emergent plants in the narrow zone
where water levels fluctuate, leading
to very high plant biomass, excessive
deposition of organic material, and
eventual loss of littoral fish habitat.
Examples where this has occurred
include the Kissimmee Chain of Lakes,
which support some of the state's most
valuable freshwater fisheries, and
many smaller lakes throughout Florida.

To reduce the influence of altered
hydrology on fish habitat, the FWC has
conducted some of the world's largest
lake habitat restoration projects.
Restoration efforts have focused on lake
drawdowns and muck (i.e., organic
plant material and sediment) removals,
with the goal of improving sport fish
populations, angler access and fishing
quality. In a previous evaluation of the
1996 Lake Kissimmee drawdown and
muck removal, Dr. Mike Allen and his
students found that habitat restoration
improved fish habitat in the treated
areas, but did not result in lake-wide
increases in the population abundance
and angler catch rates of sport fish
such as largemouth bass Micropterus

An Integrated Approach

Lake restoration projects have the
potential to benefit all components
of the ecosystem including wildlife
(e.g., amphibians, reptiles and birds)
and sport fish. However, previous
evaluations have focused on single
species and lacked an experimental
design to quantify responses. Drs.
Allen and Kitchens recently began
a seven-year project, funded by and
in collaboration with the FWC, to
evaluate fish and wildlife responses
to a habitat restoration project at Big
Gant Lake, located in Sumter County.

They will measure lake habitat
characteristics (aquatic plants and
sediment composition) and fish and
wildlife community composition and
abundance in two years of sampling
before the drawdown and five years
post-drawdown. Two control lakes
will be sampled each year to separate
effects of the restoration project from
the effects of regional drivers such as

Results of this project will aid resource
managers in designing habitat
restoration projects to maximize
benefits to wildlife and fisheries
resources. This collaborative project
is the first experimental lake habitat
restoration project in Florida, and the
goal is to use this study to improve
habitat enhancement projects in the

Satellite image of Big Gant Lake, showing
extensive coverage of macrophtes around the
lake shoreline (light green area around lake).

Contact the Authors:
Mike Allen, Email: msal@ufl.edu
Wiley Kitchens, Email kitchensw@wec.ufl.edu

Faculty Focus

Florida freshwater resources include
more than 7700 lakes and 1700
miles of rivers and streams within the
state's borders. These resources are of
substantial ecological and economic
importance but they are becoming
threatened due to rapidly increasing
demands for water to meet both human
consumption and agricultural needs.
Florida receives high levels of rainfall,
yet has tremendous water demands.

Graduate students (Towns Burgess and Jared
Flowers) hold a large sturgeon -- one species of
fish that is threatened by reduced water flow.

Competing demands for fresh water
are particularly severe and complex
in south Florida where the majority
of the state's citizens live, but where
freshwater resources are relatively
scarce. Legislation passed in 1997
mandated the development of
Minimum Flows and Levels (MFLs) for
water bodies within the state, but how
aquatic organisms respond to water
withdrawals and changes in flow are
questions needing substantial research.

While this issue is new in Florida,
western states such as Arizona,
California, and Colorado have been
wrestling with water shortages for many
years and their experiences can offer
important lessons to citizens, water
managers, and scientists in Florida.

to riverine flow
regimes in Florida
should be viewed
as a large-scale
experiment and
research efforts
should be directed
at developing techniques that can help
predict and test ecosystem responses
to flow modifications and the resulting
changes in fish habitat.

In the Florida Rivers Lab (http://
floridarivers.ifas.ufl.edu), we draw from
our experiences with the Glen Canyon
Dam Adaptive Management Program
and the associated programs monitoring
fish in the Grand Canyon reach of the
Colorado River to develop new insights
into how fish populations in Florida
rivers respond to changes in flow.
Currently, we are cooperating with the
Florida Fish and Wildlife Conservation
Commission and US Fish and Wildlife
Service to evaluate movement patterns,
habitat selection, feeding patterns, and
relative abundance of fish in several
coastal Florida rivers ranging from the
Apalachicola River in the Panhandle to
the Chassahowitzka River in southwest

A field technician from Dr. Pine's lab works with
a scientist from the USFWS to collect fish in the
Apalachicola River.

Our goal is to develop rapid evaluation
techniques that identify relationships
between fish populations, habitat
availability, and riverine flow. This
information could then be used by
resource managers to develop flow
regulations that protect riverine aquatic
resources while trying to meet the
needs of Florida's citizens for the state's
limited fresh water.

Dr. Bill Pine is an Assistant Professor in
FAS. His research focuses on processes
that structure aquatic ecosystems with an
emphasis on fish communities. Much of his
work occurs in rivers and estuaries, where
he and his students work to address major
aquatic resource management issues with
information derived from field studies,
computer simulations and ecosystem
manipulations. His recent research has
included work dealing with apex predators
in the Atlantic coastal rivers, as well as work
to help develop management plans for the
Colorado River fisheries.
Contact the author:
Email: i tdi / I i, I

Aai Ma agement

* 6'0 '0

of Naiv 0

Prior to European settlement, native fish in
the Grand Canyon portion of the Colorado
River were exclusively minnows and suckers.
The biggest of these fish was the Colorado
pikeminnow (Ptychocheilus lucius), the largest
of all native minnows in North America
(maximum size 6 feet and 80 pounds) and, like
85% of native Colorado River fish, is found
only in this basin. Today, four of the eight
species of native fish have been extirpated from
Glen and Grand Canyons (roundtail chub,
Cila robusta; bonytail, Cila elegans; razorback
sucker, Xyrauchen texanus, and Colorado
pikeminnow, Ptychocheilus lucius), while
one is listed as endangered (humpback chub,
Cila cypha) and one is listed as a candidate
species (flannelmouth sucker, Catostomus
latipinnis) under the Endangered Species Act.
The remaining two fish blueheadd sucker,
Catostomus discobolus and speckled dace,
Rhinichthys osculus) are relatively common.

Prior to the construction of Glen Canyon Dam
near the boundary of Glen and Grand Canyons,
the Grand Canyon reach of the Colorado
River was turbid and exhibited little daily but
large seasonal variability in discharge and
temperature. The post-dam river isgeneral lycold
and clear with a seasonally stable but diurnally
variable hydrograph conducive to efficient
water delivery and hydropower generation.
Whereas the pre-dam river contained the
depauperate native fish community described
above, habitat modifications and species
introductions have allowed development of a
much richer fish community where non-native
species outnumber native forms 4:1.

The Glen Canyon Dam Adaptive Management
Program is charged with advising the Secretary
of the Interior regarding resource management
in Grand Canyon.

Student Spotlight

This program has the difficult
job of both meeting water and
hydropower demands for the
growing human population
of the desert southwest and
resource conservation in
Grand Canyon. Because of

their endangered status, the
humpback chub is one of
several focal resources in this program and as
such there is much research and monitoring to
discover successful management practices.

The US Geological Survey-Grand Canyon
Monitoring and Research Center (GCMRC)
is the scientific arm of the Glen Canyon
Dam Adaptive Management Program. Since
joining the GCMRC in 2002, I have been
primarily involved with developing effective
fish monitoring programs and conducting
research on the factors controlling native fish
population dynamics. Current knowledge
suggests that likely factors influencing the
population dynamics and viability of native
fish in Grand Canyon include: 1) competition
and/or predation by non-native fish, 2) low
water temperatures that inhibit growth and
survival, 3) flow regulation that destabilizes
near-shore rearing environments, and 4) non-
native parasites and disease.

Humpback chub

Modeling has shown that factors 1-3 are likely
dominant drivers of native fish population
dynamics in this system, and controlled
manipulation of factors 1 -3 in an experimental
framework also is most tenable.
(continued on next page)


Si IFa ccTilty

Heather Hamlin
and Tina Crosby
won first and
second place
oral presentation
awards at the World
Aquaculture conference in
San Antonio, Texas.
Their faculty advisors are
Ruth Francis-Floyd and
Denise Petty, respectively.

Dr. Ed Phlips
was awarded
a 2007 Research
Seed Grant from the
University, to promote inter-
disciplinary research on
bioaccumulation, transfer
and fate of algal toxins.
Co-PIs are Shirley Baker,
Patrick Baker, Deb Murie,
Daryl Parkyn, Anita Wright
(Food Science & Human
Nutrition) and Denise
Petty (FAS & College of
Veterinary Medicine).

SJason Dotson
won the best
student paper
award at the
annual meeting of the
Florida Chapter of the
American Fisheries Society.
Matt Catalano was the first
runner-up for this award.
Both are students of Dr.
Mike Allen

Matt Catalano
also was
awarded the
Roger Rottmann
Scholarship at the Florida
AFS meeting. This
scholarship is given each
year to an outstanding
student in Florida AFS.


Florida Bay is another valuable ecosystem impacted by altered water
inputs. It is a shallow lagoon located at the southernmost tip of the Florida
Peninsula, between the mainland and a chain of islands known as the Florida
Keys. The islands were formed from ancient coral and sand shoals that became
covered by mangrove and tropical hardwood hammocks. The Bay is an area
where fresh water from the Florida Everglades mixes with salt water from the
Gulf of Mexico, forming an estuarine ecosystem with distinct biota. The Bay
is characterized by a large number of shallow inter-connected basins, most
with a depth of less than one meter. The Bay, and its associated mud flats and
mangrove islands, provide nesting and/or foraging habitat for a wide variety of animals including the American crocodile, the West
Indian manatee, the loggerhead turtle, bottlenose dolphins, and a variety of bird species and many gamefish. Certain parts of the Bay
also are nursery grounds for economically important pink shrimp and spiney lobster. The Bay's shrimp fishery is valued at over $59
million annually and the stone crab fishery at over $22 million. A guide boat industry operates in the Bay, targeting snook, tarpon,
bonefish, spotted sea trout and mangrove snapper. Until recent years, the Bay was noted for its clear water and lush seagrass beds.
However, since the 1980s, there have been large die offs of seagrass and turbid water associated with blooms of phytoplankton. These
changes have led to declines in shrimp, lobster and gamefish. In response to these changes, the State of Florida and federal government
are working together to enhance regional water management in order to restore the bay toward a more natural state. Research
regarding natural conditions of the Bay and effects of changing inflow of freshwater will provide scientific results that will be
incorporated into a plan of action as part of the Comprehensive Everglades Restoration Program.

Sources: The Florida Bay Education Project (www.floridabay.org) and the South Florida Water Management District.

Grand Canyon Fisheries (Cont'd)

In 2003, the first multi-year program of experimentation
was implemented to test policies associated with native fish
conservation. Planned treatments include: manipulations of
Glen Canyon Dam operations (discharge pattern and water
temperature) and abundance of non-native fish in a 12-mile
segment of the river deemed critical for the humpback chub.
These treatments were to be applied in a factorial design over
16 years where non-native fish control was to occur in years
1-4 and years 9-12, and experimental warming in years 9-
16 following installation of a temperature control device
on the dam. The first four years of non-native control were
quite successful with over 25,000 non-native fish removed.
Community composition in this stretch of the river is now
dominated by native fish (prior to 2003, non-native fish
constituted 95% of the community) and monitoring programs
are providing early indications of successful year classes
associated with the 2001-2003 brood years. However, due to
lowered reservoir levels associated with a drought since 2000,
unexpected warm-water releases occurred simultaneously
with non-native control. Thus, it is difficult to determine
whether the strong year classes resulted from non-native

control, elevated water temperatures, or some other factor.
Resolving this question is critical to the identification of
successful management policies for Grand Canyon. If warm
water releases and/or non-native control result in successful
recruitment of native fish, current restrictions on Glen
Canyon Dam operations might be unnecessary. Conversely,
if sustained warm-water releases facilitate the spread of the
non-native asian tapeworm (Bothriocephalus aclheilognathl
or establishment of more problematic non-native fishes (e.g.,
smallmouth bass, Micropterus dolomieu), judicious use of
warm-water releases may be necessary. The use of adaptive
management to identify strategies for conserving biological
resources is still in its infancy. If sound science and rigorous
monitoring continue to guide design and implementation of
experimental policies in Grand Canyon, this program may
yield a robust case history documenting the efficacy of adaptive
management in a large, highly modified river system.

Lew Coggins is a research scientist at the USGS Grand Canyon
Monitoring and Research Center, and he is a PhD student in FAS.
His major professor is Dr. Bill Pine.

WaterWorks is produced by the UF/IFAS Department of Fisheries & Aquatic Sciences, 7922 NW 71st Street, Gainesville,
FL, 32653. Editor: Dr. Karl Havens, Chair khavens@ufl.edu

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