Title Page
 Table of Contents
 Manatee needs
 Habitat evaluation
 Threats to survival
 Boating facilities
 Boating, swimming and fishing
 Water quality and vegetation
 Land development
 Protection of manatee habitat
 Warm-water refuges

Title: Proposed research/management plan for Crystal River manatees
Full Citation
Permanent Link: http://ufdc.ufl.edu/UF00073821/00001
 Material Information
Title: Proposed research/management plan for Crystal River manatees
Series Title: Proposed research/management plan for Crystal River manatees
Physical Description: Book
Language: English
Creator: Packard, Jane M.
Publisher: Florida Cooperative Fish and Wildlife Research Unit, University of Florida
Place of Publication: Gainesville, Fla.
Publication Date: 1983
 Record Information
Bibliographic ID: UF00073821
Volume ID: VID00001
Source Institution: University of Florida
Holding Location: University of Florida
Rights Management: All rights reserved by the source institution and holding location.
Resource Identifier: ltuf - AFN4701
oclc - 25595178
alephbibnum - 001135510


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Table of Contents
    Title Page
        Title Page
    Table of Contents
        Page 1
        Page 2
        Page 3
        Page 4
        Page 5
        Page 6
        Page 7
        Page 8
        Page 9
    Manatee needs
        Page 10
        Page 11
    Habitat evaluation
        Page 12
        Page 13
    Threats to survival
        Page 14
        Page 15
    Boating facilities
        Page 16
        Page 17
        Page 18
        Page 19
    Boating, swimming and fishing
        Page 20
        Page 21
    Water quality and vegetation
        Page 22
        Page 23
    Land development
        Page 24
        Page 25
    Protection of manatee habitat
        Page 26
        Page 27
    Warm-water refuges
        Page 28
        Page 29
        Page 30
Full Text







_ ~__ _~


This summary of the Proposed Research Management Plan for Crystal River Manatees was
written by J. Packard and C. Puckett. The conceptual design was inspired by O. Wetterqvist,
who provided valuable input throughout the preparation of the plan. This volume was design-
ed and produced by J. Ponikvar. Numerous citizens, agencies, and a project team contributed
ideas and information in preparation of the plan, as acknowledged in Volume II. We thank all
who assisted, but the views and opinions expressed are those of the project leader and are not
necessarily shared by the individuals or agencies that assisted with or funded the project.
Funding was provided by the U.S. Fish and Wildlife Service and the Marine Mammal Commis-
sion under Cooperative Agreement 14-16-0009-1544, Research Work Order No. 1. Copies may be
requested from Florida Cooperative Fish and Wildlife Research Unit, 117 Newins-Ziegler Hall,
University of Florida, Gainesville, FL 32611. Ask for: Packard, J.M. 1983. Proposed Research/
Management Plan for Crystal River Manatees. Volume I. Summary. Technical Report No. 7.
Florida Cooperative Fish and Wildlife Research Unit, University of Florida, Gainesville, FL. 31 pp.

Florida Cooperative Fish and Wildlife Research Unit
School of Forest Resources and Conservation
Institute of Food and Agricultural Sciences
University of Florida

COVER PHOTO: Courtesy Galen Rathbun, Sirenia Project, FWS

I-~it~ir^a-u^r fi--i;kuisrarcar~a~J~-rL*rLe~~,, i~.


Manatee Needs
Habitat Evaluation
Threats to Survival
Boating Facilities
Boating, Swimming and Fishing
Water Quality and Vegetation
Land Development
Protection of Manatee Habitat
Water Quality



This booklet summarizes a research/management plan devel-
oped for manatees in South Big Bend-an area that extends
from the Suwannee River to the Chassahowitzka River and in-
cludes the famous wintering waters of Crystal River. Big Bend
and the Everglades are the only two intact coastal ecosystems
remaining along Florida's coasts. Protection of the southern
portion of Big Bend will maintain a haven for manatees and ex-
ceptional recreational opportunities for humans. However,
Citrus and Hernando counties, which are adjacent to South Big
Bend's coastline, are part of the growth centers of Florida. With
planning, the needs of South Big Bend's manatees can be met
-even as human communities develop.

State and federal agencies are mandated by law to aid
recovery of the West Indian manatee population. How-
ever, the United States Fish and Wildlife Service rec-
ognizes that manatees inhabiting different geographical
regions are faced with distinct problems. Thus, plans
must be developed to protect each regionally separate
manatee group, called a subpopulation.
Site-Specific Plan for Crystal River Manatees
The Crystal River manatee subpopulation was chosen for
this pilot site-specific research/management plan for
several reasons:
* The opportunity is still available to protect
vital manatee habitat that, as yet, is relatively un-
* The growth rate of the subpopulation has re-
cently slowed.
* This subpopulation is a substantial part of the nation's
total manatee population.
* Crystal River offers a unique opportunity for
the public to view manatees and for scientific
Local Participation Is Important
Local governments possess most of the powers required
to balance human and manatee needs. By responding to

their constituents, local governments will receive the
credit for protecting their manatees, as well as for main-
taining recreational and commercial values of coastal
During development of this research/management plan,
local citizens and agencies provided input. A team of
scientists, lawyers and other experts evaluated existing
information and identified essential actions required to
meet the objectives of the plan.
Citizen support of their local and state agencies is
crucial for successful implementation of the long-term
actions needed to protect Crystal River manatees. If
local citizens and governments do not take sufficient ac-
tion to protect their manatees, then state and federal
agencies will be required to exercise their authority to in-
sure survival of a nationally significant endangered
A Guide to the Plan
This summary (Volume I), provides an overview of what is
known about Crystal River manatees and the actions
needed to protect them as described in the technical
plan (Volume II). Background information used in
developing the technical plan is available in a compen-
dium (Volume III).


LL1 Undisturbed coastline
= Urban growth centers
m Urban areas

SWaters accessible to manatees
S Wetlands and shallows

South Big Bend Management Area
Regional coordination is vital, for Crystal
River manatees roam the waters of at least
four counties-Dixie, Levy, Citrus, and Her-
nando. Manatees that spend their winters in
Crystal River wander throughout much of
the northwestern Gulf Coast during the
warm months. They are most frequently
sighted between Horseshoe Cove, slightly
north of the Suwannee River estuary, and
the Chassahowitzka River.

At present, South Big Bend provides one of
the least disturbed segments of coastal
waters available to the West Indian manatee
in the United States. However, the counties
that line this part of South Big Bend are
among the fastest growing regions in
Florida today. The area is beginning to ex-
perience habitat alteration, pollution, and
other side effects associated with unplann-

ed human growth. Elsewhere in Florida,
residents have watched unplanned develop-
ment irreversibly alter the healthy function-
ing of ecosystems. Once an ecosystem is
altered, repair is a costly and arduous pro-
cess-if even possible. By protecting the
habitat essential for manatees in South Big
Bend, we will also preserve a unique area for
the enjoyment of future generations.

Six rivers drain this southern portion of Big
Bend: the Suwannee, Waccasassa, Crystal,
Homosassa, Withlacoochee and the
Chassahowitzka. In this region, the floor of
the Gulf of Mexico is a low gently rolling
plateau that gradually slopes toward the
deep waters off the continental shelf.
Throughout South Big Bend, thousands of
shallow channels snake in intricate mazes
through vast salt marshes, whose expanses
are broken by occasional palm and hard-

wood hammocks found on slightly elevated

By land, the management area is bordered
by an almost continuous ribbon of saltwater
marshes and by occasional wooded
swamps. The offshore boundary occurs at
water depths of 20 feet (6 meters), beyond
which few submerged plants grow to entice
manatees. This shallow water extends as far
as 10 miles (16 km) offshore. Manatees rare-
ly occupy waters shallower than 3 feet (91

Within the management area, marine,
freshwater and wetland plant communities
are interrelated by the flow of water from
uplands to the sea and by the ebb and flow
of tides. All components of this coastal
ecosystem are important for the long-term
survival of manatees.






The purpose of this plan is to provide decision-makers and cit-
izens with guidelines necessary for the increase and continued
survival of manatees in South Big Bend's waters. To meet this
goal, the objectives of the plan address both the direct effects
of human activities on manatees and their indirect effects on
manatees' essential habitat. This plan outlines specific criteria
to evaluate our progress in meeting the objectives.

Crystal River manatees have been intensively studied
since the late 1960's. The slow but steady manatee in-
crease over the last decade indicates that the area has
provided good habitat.

National and Long-Term Goals
The long-term goal of the national manatee recovery
plan is to encourage the recovery of manatees in
United States' waters so that eventually the species
can be removed from its endangered listing. Because
manatee habitat is quickly dwindling in other parts of
the state, this goal probably can only be accomplished
by encouraging growth of manatee groups in areas of
optimum habitat. Therefore, the long-term goal for
management of Crystal River manatees is to maintain
the subpopulation at a level that can be sustained by
South Big Bend's healthy, naturally functioning
Short-Term Goals and Objectives
for South Big Bend
To meet the long-term goals, more specific short-term
goals and objectives were identified. The short-term
* goal of this site-specific plan is to encourage the in-
crease of manatees in South Big Bend through the

next decade. To achieve this goal, the following objec-
tives must be fulfilled:
* Human-caused mortality: Keep the number of
human-caused manatee deaths from increasing
above its present low annual rate.
* Calf mortality: Determine causes of calf mortality
and, by the end of the decade, reduce human-related
* Harassment: Determine the cumulative effects of
recreational water activities on the distribution and
number of manatees, and reduce adverse effects of
these activities.
* Food resources: Preserve the amount and the diver-
sity of freshwater and marine plant communities in
which manatees feed.
* Contaminants: Reduce the exposure of manatees
to environmental contaminants such as herbicides,
wastewater and urban runoff.
* Warm-water refuges: Maintain the flow of South Big
Bend's natural springs and keep these warm-water
refuges accessible to manatees.
* Public involvement: Maintain the aesthetic, scien-
tific and recreational value of the ecosystem that
supports manatees such that people may continue
to enjoy and benefit from manatees' presence.



The spring waters of Kings Bay, headwaters
of Crystal River, still reflect the clarity for
which the river was named and offer humans
an experience to be found nowhere else in
the world. The river's warmth in winter, its
proximity to the Gulf, and Its abundant
aquatic vegetation lure manatees through-
out the seasons. And, although manatees
gather during the winter at other warm-water
sites in Florida, in no other clear-water
refuge are humans allowed to don masks,
snorkels, and fins to enter the water world of
these large marine mammals and watch
them conduct their daily activities. Although
swimmers are not allowed to disturb
manatees, the temptation to touch when ap-
proached is almost irresistible. It is the in-
tention of this management plan to preserve
this experience for future generations.

When you dive or swim in Kings Bay, you are
in the manatees' home, a temporary, cour-
teously treated visitor, able to marvel at
sights you can see only here. You may, if it is
a cold day, see groups of manatees around
the Main Spring, an odd one sleeping belly
up on a limestone ledge, others resting on
the bottom of the bay, periodically floating
to the surface for a breath of air or a bite of
food. You may be so close you are tempted
to reach out and touch a large manatee as
it. swims by, the sun's rays through the blue
water rippling in dappled patterns over the
animal's body. At this distance, a glimpse of
the elephant-like toenails on its front flip-
pers may remind you that manatees and ele-
phants share an ancient plant-eating

Through the clear waters, you may see a
giant creature emerge from under a hydrilla
patch and watch its massive lips curl around
the tender leaf tips. If shy, the manatee may
swim away but if you are quiet and the man-
atee is accustomed to humans, he may stay
near you, the coarse bristles on his muzzle
moving with each bite of food.

Although protective females rarely trust peo-
ple near their calves, you may see a small
dark calf suckling its mother's teat under her
front flipper and another playfully twisting
and tumbling through the water in the
Banana Island sanctuary. And, if you are
lucky, a manatee may, just may, glide up to
you, peer in your masked eyes, and with a
polite but hefty bump, request a friendly



Every year more than 200,000 people move to Florida-61 per-
cent of these new residents are expected to settle along
already heavily populated coasts. With intensively developed
coastal areas in much of Florida, the aesthetic value of South
Big Bend will become increasingly important. If South Big
Bend residents take the actions necessary to protect
manatees and their habitat, their local communities will
benefit by increased tourism, higher land values and educa-
tional opportunities. Fisheries, recreation, and opportunities
for the public to view manatees will be enhanced. With protec-
tion, the number of manatees in the Crystal River subpopula-
tion is expected to increase, and this larger herd may aid in
clearing waterways clogged with vegetation.

In South Big Bend, manatees are like the coal miner's
canary, which stops singing when toxic gases build up in
a mine shaft. Similarly, the health problems of Crystal
River manatees will warn residents of environmental
degradation before effects are irreversible. If a healthy
environment is maintained for manatees, it is also main-
tained for humans.
Tourism and Recreation
Manatees are not only intrinsically fascinating, but they
are also economically beneficial. Visitors come to South
Big Bend to enjoy the recreational attributes the intact
coastal ecosystem offers. They come to fish, boat, ski,
swim, or to dive in its clean, clear waters. And they come
to see manatees. Dive shop owners in Crystal River
estimated that "800 to 1200 divers rented scuba equip-
ment each week during the 1982-83 winter manatee
season (October 15 to March 15). Many of these divers
came from northern states, some from other countries.
Other businesses also benefit from the tourism.
Shrimp, crab, oyster and fish are as dependent as
manatees on a healthy coastal ecosystem. About 100 to
125 commercial fishing boats and guides operate out of

Crystal River.
The Citrus County Marine Science Station in Crystal
River offers unique hands-on educational programs for
students of all ages. Students find manatees one of the
most fascinating animal. to observe. By learning about
manatees and the components of their habitat, these
students begin to appreciate the complexities of the rela-
tionships among marine organisms. In 1982 alone, some
8,000 to 10,000 students attended the center's programs.
The clear waters of Crystal River also offer educational
filmmakers and researchers the rare opportunity of
observing the underwater activities of manatees. Films
will be used to supplement manatee educational pro-
grams around the state.
Aquatic Weed Control
An adult manatee can eat as much as 110 pounds (50 kg)
of vegetation a day. Manatees are one of the few native
species that can help control unwanted plant growth in
coastal rivers. Although present numbers of manatees
are insufficient to keep waterways free of thick vegeta-
tion, as the herd grows, less weed control may be



Scientific Value
Piety, officially identified as CR 71, is a 14-to
15-year-old manatee. The 16 parallel scars
on her right shoulder, her docile, gentle de-
meanor and her acceptance of humans
make her particularly well known among
divers and manatee-watchers at Crystal

Piety and other identified females are giving
U.S. Fish and Wildlife Service scientists the
vital reproductive information they need to
effectively protect the Crystal River sub-

When scientists first saw Piety in winter
1972-73, she was a juvenile between the age
of 3 and 4, and had just been hit by the
rotating blades of a boat's prop-the
wounds on her shoulders were raw, ragged
and deep. On July 6, 1976, tourists at
Manatee Springs on the Suwannee River ex-
citedly reported that a manatee was swimm-
ing at the mouth of the spring. It was
Piety-the first Crystal River animal iden-
tified in the Suwannee.

Piety mated and by the time she showed up

at Crystal River in the late fall, her naturally
bulky form was even heavier with a calf. One
spring day, Piety slipped away from Kings
Bay, perhaps seeking a secluded creek in
which to give birth, far from the prying eyes
of humans and other animals. No one saw or
heard anything of Piety that summer, but
somewhere she had given birth, somewhere
she had taught her young calf the rudiments
of manatee life-patiently nudging it to the
surface for air in its first few days of life, let-
ting it rest on her back, suckling it and entic-
ing it to nibble aquatic plants with her. The
calf thrived and on November 13, Piety
returned to Crystal River with her small
daughter, whom researchers identified as
CR 1.04, and later named Constance.

For two years, Piety and her calf were in-
separable. But in the winter of 1979-80, when
researchers saw the two in the Main Spring
of Kings Bay, Constance was independent
and Piety was pregnant.

The next fall, Piety returned to Kings Bay
with her second calf. But this calf either died
or was weaned early during the summer of
1981. When Piety returned the next winter,

she was visibly pregnant once again-show-
ing researchers that a female can produce a
calf every two years.
Throughout the summer, Piety stayed near
the Suwannee River but her new calf was
never seen. Because manatees are so
secretive when calving, scientists find it dif-
ficult to determine why her third calf died.
The next winter, Piety returned to Crystal
River-once again pregnant. So far, out of
three pregnancies, only one calf definitely
survived, and one other may have lived.
In 1981, scientists saw 4-year-old Constance
"cavorting" with a group of manatees. The
group resembled a mating herd, but because
of Constance's youth, researchers were
skeptical. Existing evidence indicated that
females did not mature until about their
eighth year.

But it soon became obvious that Constance
was pregnant. Thus, scientists received
their first concrete knowledge of the age at
which some Crystal River animals can give


This plan should be reviewed and implemented by a steering commit-
tee organized by the U.S. Fish and Wildlife Service. South Big Bend
should be designated an Area of Critical State Concern, if necessary,
to aid local governments in resolving pressing needs for regional
planning regarding boating facilities, water quality and wetland pro-
tection. Additional research is needed regarding regional needs for
docking facilities, the effects of human activities on manatee
behavior, water quality in the Kings Bay area, and the factors influen-
cing the flow of natural springs used by manatees. Ongoing studies
on manatee abundance, distribution, ecology, and behavior should
also be continued.
Staff at the new Crystal River Manatee National Wildlife Refuge
should take the lead in implementing and updating this plan. An
associated private educational/research center should be developed
with attractive displays and an active interpretive program to provide
s focus for community pride. Through an enhanced public education
%,fort, harm to wintering manatees may be minimized, thus avoiding
the need for additional regulations.



For this plan to be effective, the coordinated action of
numerous agencies, private groups and citizens is need-
ed. The following actions are recommended in the plan.

Steering Committee
A steering committee composed of representatives from
appropriate agencies and groups should oversee and co-
ordinate the implementation of this plan. This committee
should meet regularly to identify tasks to be completed
each year, to resolve difficulties in completing tasks and
to respond to changes that are needed as the plan is up-
dated. Specific tasks required of each agency are listed
in the plan.

Area of Critical State Concern
Local regulations in Citrus County and the City of Crystal
River currently do not meet the recommendations out-
lined in their comprehensive plans regarding protection
of manatees, fish, wildlife and coastal resources. The
challenge for the future lies in maintaining essential fea-
tures of manatee habitat while providing for planned de-
velopment in South Big Bend. A Resource Planning and
Management Committee should be appointed under pro-
visions of the Florida Land and Water Management Act
to aid local governments in revision of regulations. Cum-
ulative impacts that need to be addressed include loca-
tion of multislip docks and other boating facilities, per-
mits and facilities for sewage treatment, zoning of wet-
lands, and construction affecting wetlands. If local reg-
ulations are not revised to be consistent with the man-
agement policies outlined in this plan, South Big Bend
should be designated an Area of Critical State Concern.

Unplanned development potentially affecting manatee
habitat should be avoided until appropriate local, state,
and federal authorities adopt regulations consistent with
the management policies of this plan. Issuance of new
permits for boating facilities, dredge, fill, septic systems,
sewage treatment services and construction in or adja-
cent to wetlands should be based on an evaluation of
cumulative effects and should not proceed until means
of assessing such effects are implemented.

Boat Traffic Study
Current boat traffic patterns and future needs for dock-
ing facilities in South Big Bend must be studied to better
define human needs. This plan specifies where docking
facilities can be placed with the least harm to manatees
and their habitat.

Water Quality Model
Baseline information on Kings Bay water quality needs

to be obtained to enforce existing regulations. A water
quality model for Crystal River needs to be developed by
the Florida Department of Environmental Regulation to
establish effluent standards based on quality of the
water body. This model will also provide the information
that is necessary to effectively regulate cumulative ef-
fects of small sewage systems, septic tanks, stormwater
discharge, and other factors influencing water quality.

Aquatic Plant Control
Adequate food for manatees needs to be maintained,
especially near winter refuges, and risks due to her-
bicides need to be reduced. Alternatives to chemical
plant control, such as mechanical harvesting, need to be
evaluated experimentally.

National Wildlife Refuge
The staff of the new Crystal River Manatee National
Wildlife Refuge needs to assume an active role in imple-
menting, reviewing and revising this plan. Crystal River
provides a unique opportunity for public enjoyment of
manatees. The refuge should develop an active educa-
tional program to enhance the experiences of visitors
while protecting manatees. Refuge personnel should
monitor manatee abundance and distribution in South
Big Bend. Lands included in the refuge should be ex-
panded as needed to protect the ecosystem upon which
Crystal River manatees are dependent.

Educational Center
A Kings Bay manatee educational center should be es-
tablished to provide a focal point where visitors can learn
about manatees and the ecology of South Big Bend. This
center, which could be partially staffed by local
volunteers, could enhance community involvement by
providing office facilities for agencies and groups involv-
ed in protecting manatees.

Manatee Research
Manatee population status should be monitored. To ef-
fectively protect the species, studies must be continued
on manatee abundance, distribution, reproduction, mor-
tality, behavior, and physiological ecology.

ManateelHuman Interaction Study
Criteria should be developed to determine how human
activities alter the normal behavior of manatees. This
study will provide decision-makers with a scientific basis
to evaluate the need for additional regulations regarding
harassment of manatees by divers and boaters.



The survival of manatees is dependent on a plentiful and varied sup-
ply of aquatic plants, appropriate water depths, shallow secluded
areas for calving, warm winter refuges, sources of fresh water, and
safe travel routes among refuges and summer ranges. The coastal
ecosystem that supplies manatees with these needs includes rivers,
estuaries, marine waters and the associated wetlands that influence
water quality and plant growth.

Aptly named sea cows, manatees are the only North
American marine mammal that grazes on aquatic
plants. They feed primarily in fresh and estuarine
waters but may crawl partway onto a bank to reach
overhanging shoreline vegetation. A variety of plant
foods is probably necessary to meet their nutritional
Manatee Feeding Behavior
To the boater whose prop repeatedly stalls in the
tangles of hydrilla in Kings Bay, there must appear to
be enough "manatee food" to support many times the
number of animals now in the area. However, hydrilla
is new to the bay and in the past manatees probably
fed primarily on estuarine seagrasses. Their wandering
habits may prevent overgrazing on plants that recover
slowly. It may be hard for manatees to change a
feeding pattern well adapted to the environment in
which they have lived for millions of years.
Water Depth
Access of manatees to vegetation and freshwater is
limited by water depth. Because animals rarely enter
water less than three feet deep (91 cm), many creeks

among the salt marsh islands are impassable at low
tide. Manatees seldom are seen in waters deeper than
20 feet (6m).

Secluded Areas
Few people have witnessed the birth of a manatee calf
in South Big Bend. Available information suggests that
females are sensitive to human intrusion and seek
shallow secluded creeks or even canals for birthing.

Warm Water
Manatees cannot tolerate prolonged water
temperatures below 61 F (16C) and usually avoid
waters colder than 680F (20C). Individuals severely
stressed by cold may die or become more susceptible
to disease and infection.

Travel Routes
Manatees traveling between familiar summer and
winter ranges seem to remain near the coast. There
probably is some exchange of manatees between
South Big Bend and areas farther south, perhaps keep-
ing the subpopulation from becoming genetically
isolated and vulnerable to the effects of inbreeding.

REFER TO SECTION 11.2, 11.3, 11.4


.-> -Runoff from uplands
is filtered through
Urban runo ff wetlands
and wastewater lu\\U (.! ,.|
affect water quality l o'oll. ,'ttII'1t.a& I /

Palm hammock (

S Shallow, secluded
areas are needed
for reproduction


Travel routes
and winter
are necessary

Health of
on salinity
and water

plants provide
for manatees
and fisheries


No natural
predators cause
harm to manatees


- L -- -- -- ~ILI


Some sites in South Big Bend provide manatees with many or all of
their requirements, hence are core centers of activity; others are not
used as intensely but are essential for specific activities. The plan
identifies Crystal, Homosassa and Suwannee rivers as areas of core
habitat and recommends that these rivers are of the highest priority
to protect. Core centers, however, are not enough to support Crystal
River manatees; connecting travel routes must also be maintained.

Seasonal Changes in Habitat
The distribution of manatees in South Big Bend changes
between summer and winter. In the winter (October
through April), manatees take shelter from cold Gulf
waters by gathering primarily in the warm spring-fed
waters of Kings Bay and Homosassa River. In the spring,
as coastal and riverine waters warm once again,
manatees return to secluded summer ranges throughout
South Big Bend. Six estuaries provide fresh water and
plant food but Crystal River and the large Suwannee
estuary attract the most "summering" manatees.
Manatees are rarely sighted in the Waccasassa River or
near Cedar Key.
Habitat Importance
The map at right is a summary of South Big Bend
manatee habitat. It is the result of grid-square analysis to
rank areas in terms of the importance to manatees. This
map provides a basis for further analysis of the impacts
of human activities on manatee habitat. The habitat rank-
ing is as follows:
* Essential Areas: Warm-water refuges at Crystal
River, Homosassa River, the Crystal River power
plant and Manatee Springs on the Suwannee River

are essential for survival of manatees. Because
South Big Bend is at the northern extreme of the
species' winter range, manatees could not remain in
the area without access to these warm-water
* Core Activity Centers: Areas where manatees have
been sighted during aerial surveys indicate core
centers where several activities occur such as feed-
ing, resting, mating and possibly calving. Distur-
bance in these areas could influence the rate at
which the population grows or declines.
* Travel Route: Core areas fulfilling manatees' winter
and summer needs must remain connected by travel
routes. Activities in these areas are not well known,
and a cautious approach is needed to avoid changes
in travel routes until their functions for manatees
are better understood.
* Supporting Ecosystem: The vegetation adjacent to
areas used by manatees is an important part of their
ecosystem. Essential hydrological and biological
functions of wetlands and offshore marine mead-
ows must be maintained to insure the quality of
manatee habitat.


I Winter warm-water refuges
SWinter & summer habitat
Summer habitat


cIII Core activity centers
= Travel routes
%/ Supporting ecosystem


Scientists gather information on manatee
habitat during biweekly aerial surveys and
by following recognizable radiotagged indi-
viduals. For example, Gus is an old, rather
ragged-looking male manatee with scaly
skin, an aged face and distinctive scars from
a boat collision-he is officially known as
CR 108. He has taught scientists about long-
distance travel routes and movements be-
tween winter refuges.

To follow Gus' travels during 1980, research-
ers attached a radiotag to his tail. Two days
later, the radio signals led scientists to Gus'
familiar form in a mating herd of one female
and several males. Later, that summer, Gus
apparently traveled 174 miles south- his
tag was found on a Sanibel Island beach in

In the fall, Gus reappeared in Kings Bay and
was retagged. One evening, he swam from
Kings Bay down to the mouth of Crystal
River and waited. Several hours later, the
tide rose and Gus swam down the shallow
Salt River toward Homosassa. Like other
manatees, Gus is active both day and night.
By the first light of the next morning, he was
back in Kings Bay, having informed re-

searchers of an inland travel route of which
they were previously unaware.

Cruz, who is named for the cross-shaped
scar that mars his back, was first identified
in Crystal River on December 19, 1978. His
movements illustrate how manatees use the
entire South Big Bend as their summering
grounds-one area does not provide all of
an animal's needs.

Cruz's movements in Kings Bay have been
followed for three winters. Typically, he
takes refuge in the Main Spring in the even-
ing when water temperatures drop else-
where in the river. In the mornings, Cruz re-
mains in the Main Spring until surface
waters warm or until he tires of interacting
with divers. Then, he slowly meanders to the
middle part of the bay, alternately feeding
and resting throughout the day. At night
Cruz returns to the Main Spring-a daily pat-
tern typical of most manatees in Kings Bay.

On January 25, 1983, scientists radiotagged
Cruz in Kings Bay. On March 16, researchers
sighted him in the warm-water discharge
canal at the Crystal River power plant. Like
other Crystal River manatees, Cruz was us-

ing the power plant canal as a temporary
refuge when moving to or from winter sanc-

Three days later, after temperatures had
fallen, Cruz returned to Bagley Cove in
Crystal River. On March 26, he was still in
Kings Bay, but by April 2, he had traveled to
the mouth of the Withlacoochee River. Three
days later, scientists saw Cruz in the canal
systems of Yankeetown on the
Withlacoochee River, an area where
manatees are seen mating and feeding.

In early May, scientists on an aerial survey
were surprised to see Cruz traveling from the
Withlacoochee toward the Suwannee River.
Somewhere between the Withlacoochee and
Cedar Key, Cruz's tail had been severely cut
by a motorboat.

On May 10, Cruz was seen at the mouth of
East Pass on the Suwannee River, an ex-
tremely important feeding and summering
area for Crystal River manatees. Cruz joined
other manatees that were cavorting in the
pass--rubbing, hugging and chasing each
other. He had traveled at least 30 miles (50
km) in seven days.












Fewer than 150 manatees live in South Big Bend. So far these ani-
mals have escaped the risks associated with the rapidly dwindling
coastal habitat in the rest of Florida: barge and boat collisions; poor
water quality; destruction of aquatic vegetation; dams that limit ac-
cess to waterways; locks that crush manatees; human disturbance
during birthing; and unreliable warm-water refuges. The species re-
produces very slowly, hence, could not offset these threats unless
farsighted management actions are taken now to minimize such
changes in South Big Bend.

There are precariously few manatees in South Big Bend.
During aerial surveys in winter 1982-83, a maximum of
116 manatees were counted at one time in Crystal River
and 21 manatees in Homosassa River. Because some
manatees are not visible during surveys, counts are used
to monitor trends in abundance, rather than representing
exact totals. However, abundance of Crystal River
manatees is well below the level (about 1,000 animals) at
which scientists become concerned about negative ef-
fects of inbreeding. If the subpopulation were to become
isolated from other groups father to the south, concerns
about maintaining a healthy population would increase.
Trends in Abundance
The Crystal River manatee subpopulation is no longer
growing at the slow but steady rate that was recorded
over the last 15 years. For example, between the winters
of 1977-78 and 1981-82, the numbers of manatees
counted in Crystal River increased from 78 to 116. In con-
trast, maximum counts of manatees did not increase bet-
ween winter 1981-82 and 1982-83. Researchers do not
know how many manatees South Big Bend can support,

but it is certain that habitat maintenance is vital for con-
tinued growth.
It takes many years for a population of manatees to in-
crease due to the species' low reproductive rate. A
female usually produces one calf every two or three
years. Even if the calves successfully make it through the
few critical years after weaning, it will take them as long
as 5 to 8 years to reach breeding age. An average of nine
calves are sighted in Crystal River each year. Some
manatees probably move into South Big Bend escaping
from the unfavorable conditions farther south-approx-
imately 10 to 20 percent of the mantees identified in
Crystal River each winter have never been identified in
the area before.
No natural predators are known to kill manatees. How-
ever, over the last eight years, an average of three
manatee carcasses per year have been recovered in
South Big Bend as part of a statewide program.
Probably not all the manatees that die are collected by
the salvage team. However, those that are examined
provide information on threats to their survival.



It is August 31, 1978. The phone rings in the
manatee salvage team's office at the
USFWS lab in Gainesvlle. The Florida
Marine Patrol reports that a boater. has
sighted a dead manatee at the junction of
Salt and Crystal rivers.
The next morning, members of the salvage
team load up a truck and head for Crystal
River. They find the animal directly across
from a marina, her large bulk floating in the
shallow channel. The manatee is hauled to
shore, lifted onto a trailer and taken to the
Gainesville lab. That same day, researchers
examine the manatee to determine the
cause of Its death and take tissue samples
for analysis of contaminants. Many manatee
carcasses are too decomposed to determine
the cause of death, but this one will provide
valuable information. A researcher writes
this terse report:
Sex of specimen: Female M-126 Length:
257 cm (8.4 ft.)
Cause of death: Six broken ribs, right
side, punctured lung, diaphragm torn from
cavity wall. Boat/barge collision.
Comments: Probable boat kill, animal was

recovered directly across from marina.
The heavily used channel is narrow and
shallow. A narrow, superficial, long cut
indicated the area that had been injured.

From 1974 through March 1982, the salvage
team recovered and examined 28 manatee
carcasses from South Big Bend. Of those
cases where the cause of death could be
determined, one fourth were human-related:
two manatees died after being hit by boats,
three were crushed by barges, one was
crushed when a canal lock closed while it
was passing through, and one death was
probably related to toxins.

Almost half of the animals recovered were
dependent calves-aborted fetuses,
stillborn, or still nursing. These calves were
found In Kings Bay, .the Withlacoochee
River, Cross Florida Barge Canal, Suwannee
River and Cedar Key. More information
needs to be collected to determine potential
causes of calf deaths.

Boats are the most frequent human-related
cause of adult manatee mortality irn Florida.

In South Big Bend, boat-related manatee
mortality is relatively low, but will most like-
ly increase if future facilities influencing
boating traffic are not carefully planned.
Several manatees in Florida have been
drowned in fishing nets, or died due to infec-
tions resulting from entanglement in crab-
trap buoys or fishing lines. One Crystal
River manatee lost a flipper after it became
entangled in monofilament line.
Although concentrations of contaminants
such as pesticides, mercury, lead and cad-
mium measured in tissues of dead
manatees as yet have been within safe
ranges, copper levels have been abnormally
high. Concentrations of copper found in the
liver of manatees recovered in northwestern
Florida were significantly higher than in
manatees recovered from other parts of the
state. Manatees probably swallowed this
copper with their food when the herbicide
was applied in large quantities in the late
1970's in South Big Bend's rivers. Manatees
also may be vulnerable to diseases and
parasites carried in poorly treated human
and animal wastewater.



To avoid the need for restrictive regulations regarding boat operation,
this plan provides guidelines for the development and location of
future navigation channels and docking facilities-marinas, docks,
and boat ramps. By locating future development of boating facilities
in areas where the overlap of boat traffic and manatee habitat is low,
the expected increase in boat-caused manatee deaths, degradation
of aquatic plant food, and manatees' exposure to contaminants will
be minimized.

Risks to manatees are high where boat traffic occurs in
waterways frequently used by manatees. These risks can
be reduced by controlling the manner in which boats are
operated, for example, by slow speed zones. However, in
South Big Bend, we still have the opportunity to avoid the
need for additional regulations by planning the location
and design of boating facilities.
Direct Impacts on Manatees
Characteristics of boat traffic that increase the chances
of injury, death or disturbance of manatees include:
* location of boating facilities near manatee areas;
* high boat density increasing collision probabilities;
* large boats, which are more likely to kill manatees
than small boats;
* shallow water, where manatees are more vulnerable.
Indirect Impacts on Manatee Habitat
Construction and operation of boating facilities can
adversely affect manatee habitat by:
* reducing the amount of aquatic vegetation;
* changing drainage patterns from wetlands;
* reducing plant growth due to increased water turbidity;
* increasing contamination of waters and sediments.

Adverse impacts of boating facilities on manatee habitat
can be minimized by appropriate design and location of
marinas, docks, and channels. Facilities should be
clustered in areas that do not require seawalls, that have
deep and well flushed channels, and that do not disturb
aquatic vegetation.

Current Regulations
Present local, state and federal regulations do not ade-
quately address the cumulative effects of boating facility
construction. For example, although the comprehensive
plans of Citrus County and the City of Crystal River
recommend protection of estuarine resources, no local
regulations currently limit the number or size of docks.
State and federal regulations do not require permits for
docks below a specified size, although state law clearly
requires protection of endangered species habitat.

Under state law, a procedure exists for making local
regulations consistent with state policy. An area with
significant environmental problems may be designated
an Area of Critical State Concern. If local regulations are
not revised according to the recommendations of a


Access points: marinas, ramps
Large boats or barges
- Small boats

Resource Planning and Management Committee, the
state authority may be invoked to supercede local
authority until appropriate measures are taken. However,
substantial unplanned development may occur in the in-
terim unless involved agencies agree to a moratorium
until the satisfactory regulations are adopted.
Regional Evaluation
By analyzing the overlap of current boat traffic and
manatee habitat, major areas of concern within South
Big Bend were identified (see maps on this page). Impor-
tant manatee habitats in Crystal, Homosassa, Suwan-
nee, Withlacoochee, and Chassahowitzka rivers are
already centers for boating activity. The shallow Wac-
casassa River is relatively inaccessible to boats or
manatees; however, small fishing boats cluster in the
estuary where manatees are occasionally sighted.
Although Cedar Key is becoming a center for boating ac-
tivity, it does not attract many manatees. The barge
canal, currently undeveloped, stands out as a navigable
channel with minimal overlap of manatee habitat.
Plans already exist for construction of two major naviga-
tion channels that would create significant adverse ef-

O High overlap
O Medium overlap
~ Low overlap

fects on manatee habitat in South Big Bend. The Cross
Florida Barge Canal is still authorized although construc-
tion was stopped before it was completed. An In-
tracoastal Waterway from Tampa Bay to St. Marks has
been proposed and further studies have been recom-
mended by the Withlacoochee Regional Planning Coun-
cil. Currently, large boats travel in offshore waters at dep-
ths infrequently used by manatees and dock at Crystal,
Homosassa, Suwannee and Withlacoochee rivers. Con-
struction of major navigation channels such as the In-
tracoastal Waterway or the barge canal would encourage
more inshore large-boat traffic, substantially increasing
the probability of manatee deaths due to boat/barge col-
To identify locations where construction of boating
facilities in South Big Bend will minimize impacts on
manatee habitat, areas with substantial overlap of boat
traffic and core habitat were analyzed at a larger scale
for each river system. Sites were evaluated as suitable
for construction of boating facilities only if they satisfied
both of the following criteria: (1) minimize the amount of
boat traffic in areas where manatees are frequently
sighted, and (2) minimize disturbance to wetlands.




Crystal River
Ten boat ramps and marinas are located in the Crystal
River area. Commercial fishing boats travel the entire
length of the river to gain access to Gulf waters from
Kings Bay. Throughout the year, manatees are frequently
sighted in the estuary and the river channel is their only
access to the warm headwaters during the winter. Thus,
the current overlap of boat traffic and manatee habitat in
Crystal River is high.

No sites suitable for construction of multislip docking
facilities were identified in Crystal River or Kings Bay. In
general, overlap of boat traffic and manatee travel routes
would be minimized by locating boating facilities at the
mouth of the river. However, these areas are primarily
wetlands and are unsuitable for marina development.
The water is generally too shallow in Dixie Bay, and traf-
fic from canals adjacent to the river would increase boat
density in the river.

This analysis indicates that the capacity for multislip
docking facilities on Crystal River and Kings Bay has
been reached. Thus, existing facilities should not be ex-
panded and future development should be redirected
outside of core manatee habitat, to areas such as the
>arge canal.

Homosassa River
Boat traffic from the nine marinas and ramps located on
the Homosassa River travels along the same route used
by manatees traveling between estuarine feeding areas
and the warm headwaters. No sites met both criteria as
suitable for further development of multislip docks. This
preliminary analysis indicates that development of
boating facilities should be redirected to locations out-
side of the core manatee habitat in Homosassa River,
although a more detailed analysis is recommended.

Withlacoochee River and Barge Canal
Compared to other areas in South Big Bend, the barge
canal is most suitable for future development of multislip
docking facilities. Well-drained land is adjacent to the
canal east of a band of coastal wetlands. The canal is in-
frequently used by manatees and does not contain a
significant source of food for manatees. The canal is
deep enough to allow manatees to dive under ap-
proaching boats. Although much of the lower
Withiacoochee River is not bordered by wetlands,
development of docking facilities along the river would
generate boat traffic that would travel through areas us-
ed by manatees in the summer.

Suwannee River
'"anatees are sighted frequently during the summer at

the Suwannee estuary and also travel up the Suwannee
River at least as far as Manatee Springs. If more docking
facilities are constructed along the river, the risk of injury
and death to manatees would increase. Most of the
waterways at the mouth are surrounded by wetlands and
therefore are unsuitable for development of marinas.

Chassahowitzka River
.No suitable areas for development of docking facilities
on the Chassahowitzka River could be located. The en-
tire river is surrounded by wetlands and is shallow.
Manatees are sighted in the estuary during the summer
and boat traffic from the river travels through the estuary.

Information Needs
This analysis indicates that severe problems will occur in
the future if unplanned development of docking facilities
in South Big Bend continues. However, a more detailed
analysis of boat traffic trends is needed to draft and im-
plement regulations to avoid such problems. Regional
planning that considers the cumulative effects of
development of boating facilities in South Big Bend is

Management Policy
To meet the objectives of this plan, future actions in
South Big Bend should be consistent with the following
management policy:
* Approve permits for construction of new (or expanded)
boating facilities only where it can be shown that the
overlap of boat traffic and manatee habitat will not in-
crease, vegetation eaten by manatees will not be re-
duced and the role of wetlands in maintaining water
quality and estuarine vegetation will not be altered.
Determine and implement a process for evaluating the
cumulative effects on boat traffic during review of per-
mit applications for construction of boating facilities.
Redirect new development of multislip docking facili-
ties and boat ramps to the barge canal between Lake
Rousseau and coastal wetlands.
Encourage relocation of existing facilities to areas
that will reduce overlap of boat traffic and manatee
Establish and require design standards for construc-
tion of boating facilities.
Issue permits for maintenance dredging only where
large boat traffic in core manatee habitat will not in-
crease, and aquatic vegetation utilized by manatees
will not be reduced.
Allow one small dock per existing waterfront lot.






SSuitable site:
meets criteria 1 & 2

1111 Meets criterion 1: minimizes
lill manateelboat traffic overlap and
disturbance of aquatic plants
Meets criterion 2: minimizes
disturbances to wetlands and
supporting manatee habitat
Manatee sightings







Opportunities for the public to view manatees should be preserved
and enhanced; however, additional effort is needed to enforce regula-
tions that protect manatees from injury, harm and harassment, and
to investigate the effects of human activities on manatees. The need
for further regulations may be avoided by developing an effective
public education program that explains rules of conduct in manatee
areas. Development of the Crystal River Manatee National Wildlife
Refuge and an associated educational center is essential.

Manatees and humans are attracted to the same areas in
South Big Bend. However, it is possible to minimize the
effects of recreational activities on manatees, by minor
adjustments in the manner in which these activities are

Impacts on Manatees
Boating, snorkeling, diving and fishing in winter refuges
may cause manatees to leave warm-water areas, expos-
ing them to cold stress. Factors increasing to the likeli-
hood of manatee injury, mortality and disturbance in-
fast or unpredictable operation of boats;
disturbance during cold compared to warm periods;
behavior and density of boats, divers and snorkelers;
crab-trap lines and discarded monofilament line.

Current Regulations
Except for the Suwannee estuary, boat speed is
regulated in each of the areas of core manatee habitat
within South Big Bend and all activities are excluded
from three small sanctuaries in Kings Bay during months
that manatees are present. Activities resulting directly or
indirectly in injury, death, harm or harassment of

manatees are prohibited, wherever they may occur, by
state and federal laws.
Management Policy
To meet the objectives of this plan, future actions should
be consistent with the following management policy:
* Improve regulatory means of reducing harm to
manatees, for example, by increasing enforcement
manpower, repairing signs, posting signs, extending
dates of boat speed regulations, and establishing boat
speed zones in shallow waters adjacent to the Crystal
River channel.
* Develop an active interpretive program at the Crystal
River Manatee National Wildlife Refuge and an educa-
tional center in Crystal River to strengthen apprecia-
tion, awareness and citizen involvement in protection
of manatees.
* Monitor and evaluate the effects of human activities
on manatees in Kings Bay, to develop objective
criteria for determining the need for additional regula-
* Emphasize voluntary time-sharing of areas where
manatees and human activities overlap to avoid the
need for additional regulations.
* If voluntary compliance with guidelines for minimiz-
ing harm to manatees is inadequate, establish reg-
ulations as necessary.



Site-specific Evaluation
The greatest overlap of human waterborne activities and
core manatee habitat occurs in Crystal and Homosassa
rivers-areas essential to survival of manatees in South
Big Bend. Analysis of each of the areas of core habitat in-
dicates that regulations are currently not adequately en-
forced and effort should be focused on a positive pro-
gram of public education to aid enforcement.

An estimated 600 to 800 people rent equipment from
Kings Bay marinas and dive shops each winter weekend.
The major attraction, the Main Spring, is also the major
warm-water refuge for manatees. As many as 33 boats
have been counted clustered at one time in the Main
Spring area adjacent to no-entry manatee sanctuaries.
The small sanctuaries do not exclude people from
fishing holes, navigation channels or recreational
diving at the Main Spring. Manpower for law
enforcement and funding for signs are
inadequate-local residents report numerous
violations of the rules. One problem is that a visitor
new to the area is unlikely to encounter information
explaining rules of conduct in manatee areas.

Water skiing
Large boat traffic

Areas where manatees are sighted most frequently in
Kings Bay, are appropriately protected by slow and idle
speed zones. Time sharing occurs-boaters enjoy water-
skiing during summer months when manatees are
sighted less frequently. However, the current period of
speed zones (November 15 to March 15) does not ade-
quately cover the period that manatees are sighted in the
bay (October 15 to April 15). Boat speed is not restricted
in the Crystal River channel where boat traffic is fre-
quent. Manatees are vulnerable in shallow areas adja-
cent to the unmarked channel.

Opportunities to develop an effective educational pro-
gram exist. Recently, a voluntary Manatee Watch involv-
ing private citizens was organized to patrol Kings Bay. It
will educate the public regarding guidelines for conduct
in manatee areas, and provide law enforcement officers
with information necessary to enforce existing laws. Five
commercial dive shops direct customers to areas where
manatees can be viewed and most provide some infor-
mation on manatee regulations. The Citrus County
Marine Science Station provides supervised field trips to
view manatees. Two rehabilitated captive manatees are
on display at a commercial attraction in Homosassa.



Clean, unpolluted water and plentiful vegetation are vital not only to
manatees but also to fisheries and recreation. Maintenance of water
quality in Crystal River is still possible if standards for permitting ef-
fluents and individual sewage systems are based on a water quality
model that includes all inputs to the river. Use of herbicides in South
Big Bend should be reduced due to their potential negative effects on
health of manatees.

Impacts on Manatees
Contaminants such as human and animal wastes, heavy
metals, industrial by-products, or pesticides and radioac-
tive wastes may influence manatees' susceptibility to
disease and may affect their reproduction. Sources of
these contaminants may include sewage, stormwater
runoff, aquatic herbicides, or industrial effluents. The
diversity and abundance of aquatic plants eaten by
manatees is influenced directly by weed control pro-
grams and indirectly by water quality.
Current Regulations
Selected manatee feeding areas in Kings Bay are pro-
tected from herbicide treatment, and application of
chemicals evaluated as potentially most hazardous to
manatee health has been reduced due to coordinated ef-
fort of county, state and federal agencies. Because
Crystal River is classified as an Outstanding Florida
Water, new point sources of pollution must not degrade
water quality below current levels. However, baseline
water quality conditions in Kings Bay have not been
established, making enforcement difficult. State regula-
tion of septic tanks and small package treatment plants

is not adequate in areas draining into Crystal River.
Management Policy
To meet the objectives of this plan, the following man-
agement policy should be implemented:
* Establish and maintain water quality standards in
Crystal river based on baseline water quality informa-
* Establish water-body based effluent standards, by
modeling the Crystal FRver aquatic ecosystem.
* Control the construction of individual sewage systems
in areas that influence water quality in manatee
* Provide future sewage treatment facilities that do not
degrade coastal waters.
* Provide for independent monitoring of effluents dis-
charged into Crystal and Homosassa rivers, and en-
force permit requirements.
* Reduce the exposure of manatees to aquatic herbi-
cides used in South Big Bend, i.e. by a program of
mechanical harvesting that is designed to be safe for
manatees, and by restoring water quality to decrease
the need for aquatic weed control.


- Feeding areas
O Herbicides restricted

Site Specific Evaluation
In South Big Bend, the poorest water quality and the
greatest use of herbicides occurs in rivers that are core
manatee habitat-Crystal River, Homosassa River, and
the Suwannee River. In this plan, analysis focuses on
maintaining water quality and vegetation in the most ur-
banized area within South Big Bend, Crystal River.

Wastewater treatment facilities draining into Crystal
River include a secondary sewage treatment plant, at
least 13 sewage treatment package plants and numerous
septic systems. Four package plants and two septic
systems have already been identified as not meeting
water quality standards. Manatees are susceptible to
diseases and parasites carried in inadequately treated

Because of high fecal coliform levels, shellfish
harvesting has been closed each winter for the last three
years in the Crystal River area, and the Hunters Spring
swimming beach has been closed several times. The
Department of Natural Resources identified the Crystal
River and Dixie Shores wastewater treatment plants as

* Sewage plant discharge
A Sewage treatment problem
1i Urban areas-runoff

the worst sources of bacterial pollution along the Citrus
County coast and noted that septic systems with poor
drainage probably contributed to the problem.
Enriched with nutrients from sewage and runoff from
residential gardens, the waters of Kings Bay now favor
plant growth more than in the past. Use of herbicides to
control aquatic plants may contribute to the pro-
blem-decaying plants release silt and nutrients into the
water. Although sufficient food for manatees is assured
by limiting herbicide treatment in selected manatee
feeding areas, manatees are still exposed to herbicides
applied in other parts of Kings Bay and adjoining canals.
Information Needs
Additional information is needed to determine a long-
term solution to maintaining water quality and controll-
ing vegetation in Kings Bay and Crystal River. A water
quality model needs to be developed to provide a scien-
tific basis for evaluating the cumulative effects of ef-
fluents and seepage from septic systems located in
poorly drained soils. To aid in reducing herbicide
treatments, the feasibility of mechanical harvesting of
aquatic plants should be evaluated.


0 2


Development of land adjacent to manatee habitat should be planned
such that it does not disturb the natural functions of the coastal eco-
system. By setting design standards and clustering development in
appropriate locations, the vast expanses of wetlands, which are so
important to water quality and the beauty of the area, may be preserv-
ed. Developers will know the guidelines within which to plan their pro-
jects, thereby easing current uncertainties.

Effects of Unplanned Development
Although the effects of land development on manatees
are indirect, they nevertheless are important. Viewed on
a case by case basis, it may be difficult to see how each
development project would have a substantial impact on
the coastal ecosystem as a whole. However, when view-
ed in terms of the total development that could take
place in the next decade in Citrus County coastal areas,
the impact could be substantial. Dredged canals, fill, and
seawalls required to develop wetlands can alter drainage
patterns, nutrient exchange, and filtering functions, all of
which are important to maintain healthy estuarine plants
and water quality.
Current Regulations
Contrary to guidelines of their comprehensive plans, the
city of Crystal River and Citrus County zoning regulations
have few provisions for maintaining the quality of coastal
areas. For example, lands adjacent to Crystal River are
zoned residential, commercial, industrial and agricultural
(see map on page 25). State and federal agencies that
regulate dredge and fill activities have clear guidelines to
consider cumulative effects on the habitats of endan-

gered species. However, there is currently no accepted
procedure for assessing those cumulative effects.
Management Policy
To meet the objectives of this plan, future actions should
be consistent with the following management policy:
* Protect the natural condition of wetlands adjacent to
manatee habitat by means of specified conservation
* Identify buffer zones suitable for limited development
under design standards that minimize disruption of
ecosystem functions, and specify the type of develop-
ment that will be permitted to meet such standards,
for example, cluster housing, stilt houses and board-
* Redirect high-density development to locations where
drainage from uplands into wetlands will not be
* Reduce unplanned development affecting manatee
habitat until a regional plan addressing the cumula-
tive effects of development is prepared and imple-


M Marshes and Wooded Wetlands

Site Specific Evaluation
The major area of proposed compact urban development
in South Big Bend includes wetlands on the Salt, Crystal
and Homosassa rivers. The second largest area of pro-
posed development is along the north bank of the
Withlacoochee, including the communities of
Yankeetown, Crackertown and Inglis. Therefore, the ma-
jor overlap of proposed development and lands adjacent
to manatee habitat occurs on the Crystal, Homosassa
and Withlacoochee rivers.

This study focused on an analysis of land use adjacent
to the most important manatee habitat, Crystal River. Ex-
isting and pending permits indicate that development is
proposed in the immediate future along the southern and
northern shores of Crystal River. These are primarily mar-
shes and wooded wetlands less than 5 feet above sea
level, except for scattered hammock islands and ex-
isting fill.

Wetlands adjacent to Crystal River and Dixie Bay main-
tain water quality and plant growth in the estuary fre-
quented by manatees. Under current zoning, these
wetlands could be divided into lots ranging from about
one to two acres and could be developed for a variety of


; Industrial

purposes, including residences, commercial activities
and industry. Essential biological and hydrological func-
tions of wetlands will be impaired if these low lands are
developed-thus, wetlands should be conserved in their
natural state.

Limited development should be allowed to occur on
lands adjacent to wetlands only if it meets stringent
standards. Zoning regulations are needed in these areas
to specify the performance standards necessary to main-
tain environmental quality, for example, by requiring low
density, cluster housing, stilt construction, and centraliz-
ed sewage treatment.

Information Needs
The boundaries of the salt and freshwater wetlands adja-
cent to Crystal River need to be mapped in sufficient
detail to provide guidance for developers, permitting
agencies and for revision of local zoning regulations.
Drainage patterns need to be determined to evaluate the
effects of proposed developments on coastal marshes
and on salinity fluctuations in the Crystal River estuary.
Potential effects of development adjacent to
Homosassa, Chassahowitzka, Withlacoochee and
Suwannee rivers need to be determined.



South Big Bend residents have the opportunity to maintain their pro-
ductive coastal ecosystem by expanding the present system of state
and federal refuges, reserves and preserves to include currently un-
protected lands adjacent to manatee habitat. By protecting wetlands,
fisheries and human recreational activities will also be preserved.
Maintenance of good habitat is less costly than restoration.

An intact coastal ecosystem is essential to maintain
good habitat for manatees. Despite regulations, the
cumulative effects of human activities along the coast
will inevitably reduce the quality of the manatee habitat.
The most sensitive areas should be maintained intact,
and placed in public or private trust.
Current Regulations
State lands managed as reserves protect unique
features, whereas preserves and parks provide for recrea-
tional activities. Aquatic preserves specify protective
guidelines for actions permitted on sovereignty submerg-
ed lands. National wildlife refuges are managed by the
federal government for wildlife and commercial
resources. Management plans developed for these
public lands can include measures to protect manatees.
Habitat protection can also be provided by federal
designation of Critical Habitat for endangered species,
and of national marine sanctuaries.
Information Needs
The current patterns of land ownership and the availabili-

ty of funds for acquisition need to be determined before
protective options can be fully evaluated. The
movements of manatees outside Crystal River need to be
studied to provide a better basis for identifying areas im-
portant for reproductive activities.

Management Policy
To meet the objectives of this plan, actions should be
consistent with the following management policy:
* Encourage the expansion or addition of state refuges,
reserves, preserves, parks, etc. in or adjacent to es-
sential manatee habitat.
* Incorporate a full complement of essential summer,
winter, and migratory habitat for manatees into the re-
gional system of state and federal protected areas.
* Encourage the development of research/management
programs that address manatee protection at estab-
lished refuges, reserves, preserves, and parks that con-
tain essential manatee habitat.
* Designate waterways identified as core manatee habi-
tat as Critical Habitat.


". Proposed aquisitlon
.Protected public lands


Site-Specific Evaluation
A continuous band of wetlands lines the coast of the
management area. Many of these wetlands are already
included in existing refuges, reserves, and preserves.
Proper management of these areas will help protect the
integrity of the coastal ecosystem that supports South
Big Bend's manatees. Although many of the areas
already protected contain important manatee habitat,
some of the most vital habitat remains unprotected.
Coastal wetlands that are not currently protected in
South Big Bend include portions near the Suwannee
River, a segment between the Withlacoochee and
Homosassa rivers, and areas east of Chassahowitzka
National Wildlife Refuge.

Completion of proposed federal acquisitions for the
Lower Suwannee National Wildlife Refuge, and propos-
ed state acquisitions of lands adjacent to Cedar Scrub
State Reserve, lands south of Crystal River, and the
Chassahowitzka Swamp will contribute substantially to
the protection of manatee habitat. Also, the proposed

Big Bend Grassbeds National Marine Sanctuary would
protect seagrass meadows north of Suwannee.
Existing state lands adjacent to manatee habitat include
Manatee Springs State Park, Cedar Scrub State Reserve,
Waccasassa Bay State Preserve, St. Martin's Marsh
Aquatic Preserve and a parcel adjacent to Crystal River.
Protected federal lands include the Cedar Key,
Chassahowitzka, Crystal River Manatee and portions of
the Lower Suwannee national wildlife refuges. Crystal
River is designated Critical Habitat for manatees.
Therefore, wetlands adjacent to core manatee habitat
are partially protected near the Suwannee, but not pro-
tected near Crystal River. Only a portion of important
manatee habitat in South Big Bend has been designated
Critical Habitat. The lower Suwannee, lower Withla-
coochee, and Homosassa rivers should be designated as
Critical Habitat. Expansion of the Crystal River Manatee,
Lower Suwannee, and Chassahowitzka national wildlife
refuges is needed to provide full protection of core
manatee habitat.





The quantity of water flowing from South Big Bend's springs needs to
be maintained to insure the protection of essential warm-water
refuges for manatees. If water withdrawal from the aquifer that pro-
vides spring water exceeds recharge rates, the volume of water
warmed by springs may drop, salinity of river waters may increase,
and flow patterns could change or cease. Estuarine and even marine
vegetation could be altered. The preservation of the natural flow of
these springs should merit priority over other water uses, not only due
to their importance for manatees, but also for fisheries and recrea-
tional values.

The quantity or salinity of water flowing from natural
springs in Kings Bay or Homosassa River might be al-
tered by water withdrawal from the aquifer or reduction
of recharge areas. If the volume of water flowing from
springs decreases, water temperature around springs
may drop, increasing manatees' exposure to cold waters
and its associated health risks. Over the long-term, man-
atees would be more likely to leave the area for warmer
refuges. The salinity of estuaries and rivers could
change, resulting in degradation of estuarine vegetation
and fewer sources of fresh water for manatees.
Current Regulations
Water management districts, which regulate consump-
tive use of water, can deny permits for uses that are not
in the public interest. Any water-use substantially reduc-
ing the flow of springs in Crystal and Homosassa rivers
is clearly contrary to the public interest. However, the
State Water Use Plan does not currently designate
preservation of natural springs in Crystal and
Homosassa rivers as a priority water-use. Studies are
now in progress to establish minimum flow standards for
the rivers in South Big Bend.

Information Needs
The effects of springs on water temperature in Kings Bay
and the headwaters of the Homosassa River need to be
determined. A model needs to be developed to predict
the effects of water withdrawal and alteration of
recharge areas on the flow of springs in Crystal and
Homosassa rivers.

Management Policy
To meet the objectives of this plan, actions should be
consistent with the following management policy:
* It is in the public interest to maintain the flow of
springs that manatees use as warm-water refuges; and
these springs merit priority over consumptive use of
water in the Withlacoochee region.
* When permitting consumptive water uses, agencies
must consider the cumulative effects of water with-
drawals from the aquifers that supply the region's
* The needs of manatees should be considered in set-
ting minimum flow standards for the rivers in South
Big Bend.


0 Major refuges
O Minor refuges

* Natural spring
O Site where manatees gather

* Natural spring
O Site where manatees gather







Manatees have captured the imagination, respect, and scientific in-
terest of people throughout the nation and the world. Current
development trends threaten the integrity of the coastal ecosystem
that supports manatees in South Big Bend. With foresight, the sur-
vival and growth of the Crystal River manatee subpopulation can be
assured if the recommendations listed in this plan are implemented.

Boating Facilities
By planning the location and size of future boating
facilities in South Big Bend, risks to manatees can be
reduced. Under current regulations, boat density and the
proportion of large to small boats is expected to increase
at almost all coastal access points. As a result of these
probable changes, the probability of manatee mortality
would increase.
Boating, Swimming and Fishing
The rare opportunity to view manatees in Crystal River
should be preserved; however, the regulations that pro-
tect manatees must be enforced. An effective public
education program will reduce the need for further
regulations. If recommendations of this plan are not im.
plemented, the density of boats and swimmers in Kings
Bay will increase, disturbing manatees and exposing
them to cold stress and injury.
Water Quality and Vegetation
Maintenance of good water quality in Crystal River is still
possible if permitting standards are based on a com-
prehensive water quality model. The use of herbicides in
South Big Bend's waters should be reduced because of
their potential harm to manatees. Under current regula-
tions, manatee food resources in Kings Bay will remain
adequate, but estuarine vegetation will decline due to

adverse changes in water quality and salinity. Chemical
contaminants and risk of disease from inadequately
treated wastewater will increase, possibly impairing the
health of manatees.
Land Development
By setting design standards and clustering land develop-
ment in appropriate locations, the natural functions of
the coastal ecosystem can be preserved. If recommenda-
tions of this plan are not implemented, the cumulative ef-
fects of unplanned land development will severely
reduce the quality of manatee habitat.

Land Protection
The productive South Big Bend coastal ecosystem can
still be maintained by expanding the present system of
state and federal refuges, reserves and preserves. If
wetlands are left unprotected, patterns of water flow and
water quality could be altered, reducing the ability of the
area to support manatees.

Warm-Water Refuges
Natural springs are the Crystal River manatees' essential
refuges from cold winter waters. Regulations should be
enforced to insure that human water demands do not
adversely affect the-flow of these springs.


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