Salinity and Temperature Tolerance Experiments 

 on Selected Florida Bay Mollusks

U.S. Geological Survey Open File Report 2006-1026

James B. Murray and G. Lynn Wingard

U.S. Department of Interior

U.S. Geological Survey
1

Salinity and Temperature Tolerance Experiments 

 On Selected Florida Bay Mollusks 

The ultimate goal of the Comprehensive Everglades Restoration Plan (CERP) is 

to restore and preserve the unique ecosystems of South Florida, including the estuaries. 

Understanding the effect of salinity and temperature changes, beyond typical oscillations, 

on the biota of South Florida’s estuaries is a necessary component of achieving the goal 

of restoring the estuaries. The U.S. Geological Survey has been actively involved in 

researching the history of the South Florida Ecosystem, to provide targets, performance 

measures, and baseline data for restoration managers. These experiments addressed two 

aspects of ecosystem history research: 1) determining the utility of using molluscan shells 

as recorders of change in water chemistry parameters, primarily salinity, and 2) 

enhancing our in situ observations on modern assemblages by exceeding typically 

observed aquatic conditions. This set of experiments expanded our understanding of the 

effects of salinity, temperature and other water chemistry parameters on the reproduction, 

growth and overall survivability of key species of mollusks used in interpreting sediment 

core data. Observations on mollusks, plants and microbes made as part of these 

experiments have further refined our knowledge and understanding of the effects of 

ecosystem feedback and the role salinity and temperature play in ecosystem stability. 

The results have demonstrated the viability of several molluscan species as indicators of 

atypical salinity, and possibly temperature, modulations. For example Cerithium 

muscarum and Bulla striata demonstrated an ability to withstand a broad salinity and 

temperature range, with reproduction occurring in atypically high salinities and 

temperatures. These experiments also provided calibration data for the shell 

biogeochemistry of Chione cancellata and the possible use of this species as a water 

chemistry recorder. Observations made in the mesocosms, on a scale not normally 

observable in the field, have led to new questions about the influence of salinity on the 

localized ecosystem. The next phase of these experiments; to calibrate growth rate and 

reproductive viability in atypical salinities is currently underway. 
2

Table of Contents 

Abstract ................................................................................................... 1 

Acknowledgments .................................................................................. 4 

Introduction............................................................................................. 4 

Natural Setting ........................................................................................ 5 

Experimental Design and Purpose.......................................................... 6 

Mesocosms.............................................................................................. 7 

Results..................................................................................................... 8 

Discussion............................................................................................... 13 

Summary ................................................................................................. 15 

References............................................................................................... 49 

Figures 

Figure 1 Site Map of Southern Florida showing sites of data collection 

and the Whipray Basin habitat location.................................................. 16 

Figure 2A-B NOAA winter temperature and precipitaion averages...... 17 

Figure 3A-B NOAA summer temperature and precipitaion averages....18 

Figure 4 Little Madeira seasonal salinity values .................................... 19 

Figure 5 Salinity regimes of basins within Florida Bay ......................... 20 

Figure 6 Historical salinity values for basins within Florida Bay ......... 21 

Figure 7 Location and pictures of WB habitats...................................... 22 

Figure 8 Schematic of Mesocosm tank design at the Leetown Science 

Center WV ............................................................................................. 23 

Figure 9 Photo of the Mesocosms in the Leetown greenhouse ............. 24 

Figure 10 Salinity and temperature comparison between LSC and 

Whipray Basin Florida............................................................................ 25 

Figure 11 Close up photo of the mesocosm substrate showing 

some of the tank inhabitants ................................................................... 26 

Figure 12 Comparison of data logger temperature profiles at LSC and 

Whipray Basin ........................................................................................ 27 

Figure 13 A-B Brachidontes exustus percent remaining in each of the 

experimental systems.............................................................................. 28 
3

Figure 14 A-B Bulla striata percent remaining in each of the 

experimental systems.............................................................................. 29 

Figure 15 A-B Cerithium eburneum percent remaining in each of the 

experimental systems.............................................................................. 30 

Figure 16 A-B Cerithium muscarum percent remaining in each of the 

experimental systems.............................................................................. 31 

Figure 17 A-B Chione cancellata percent remaining in each of the 

experimental systems.............................................................................. 32 

Figure 18 A-B Columbella rusticoides percent remaining in each of the 

experimental systems.............................................................................. 33 

Figure 19 A-B Modulus modulus percent remaining in each of the 

experimental systems.............................................................................. 34 

Figure 20 A-B Prunum apicinum percent remaining in each of the 

experimental systems.............................................................................. 35 

Figure 21 A-B Turbo castanea percent remaining in each of the 

experimental systems.............................................................................. 36 

Figure 22 Comparison of all experimental systems ............................... 37 

Table 1 Duration table ............................................................................ 38 

Table 2 Duration in Days for Species within the experimental systems.

................................................................................................................. 39 

Appendix................................................................................................. 40 

Leetown Science Center --Working Mesocosm Species List ................ 41-48 
4

Acknowledgments 

We would like to thank Everglades National Park (ENP) for their cooperation in this 

study; the work described here was conducted under study #EVER-00141; and Permits 

2000-004; EVER-2001-SCI-0048; EVER-2002-SCI-0038; EVER-2003-SCI-0053; 

EVER-2004-SCI-0099. This work was funded by the U.S Geological Survey (USGS) 

Priority Ecosystem South Florida Study Unit. We also would like to thank Leetown 

Science Center for facilities support for these experimental studies, and Bane Schill and 

Frank Panek, USGS, (BRD), Leetown Science Center for scientific and financial support. 

Robert G. Stamm, Carlos Budet and Joel Hudley, USGS, assisted in field data collection 

and graphic representations. Water monitoring data were provided by ENP, and South 

Florida Water Management Department. We also would like to thank our reviewers, 

William, Bane Schill and Dr. Lucy Edwards for their thoughtful and thorough reviews of 

the manuscript. 

 INTRODUCTION 

The South Florida ecosystem is currently undergoing a massive ecosystem 

restoration effort, utilizing private institutions and local, state, and federal government 

agencies. The restoration efforts are being coordinated by the Comprehensive Everglades 

Restoration Plan (CERP). The primary goal of the CERP is to restore more natural 

freshwater flow through the south Florida ecosystem including quantity and timing of 

freshwater deliveries into the system, and maintaining water quality within the overall 

system. Over the past century, changes have occurred in freshwater delivery from the 

terrestrial Everglades to the estuaries of South Florida due to anthropogenic activities. 

The construction of dams, canals, and other water control structures, and the increases in 

population with the resulting land-use change and road construction have restricted or 

diverted the natural flow of water through the Everglades ecosystem (Light and Dineen, 

1994). These changes to the terrestrial ecosystem have altered the natural variability of 

the seasonal salinity cycle of the estuaries, including Florida Bay, Biscayne Bay and the 

southwest coastal areas (Figure 1). 

Since 1995, several USGS projects have focused on the ecosystem history of 

South Florida. The role of ecosystem history research is to determine natural cycles of 

change prior to human alteration of the environment, to identify the range of natural 

variation, and to attempt to separate natural change from anthropogenic change. 

Ecosystem history research functions on basic paleoecological principals, including the 

principal of uniformitarianism – the present is the key to the past. Therefore, a 

significant component of the research has involved studying the modern environment and 

the ecology of the living biota of South Florida. Information on the modern environment 
Florida Bay

Biscayne

Bay

Gulf of

Mexico

Atlantic Ocean

Joe Bay

Little Madiera Bay

Terrapin Bay

Habitat Site

Water Depth

Whipray Basin

� � � �

Miles

> 3 feet

< 3 feet

Figure 1. Site map showing South Florida Region
5

is then used to interpret biotic assemblages found in sediment cores collected from 

around the region. 

Understanding the history of an ecosystem over biologically significant periods of 

time is an essential component of restoration because, in order to establish realistic and 

obtainable performance measures and targets for restoration, it is critical to first 

determine how the system functioned historically. A better understanding of how human 

activities and natural cycles affect ecosystems can be obtained by observing potential 

cause and effect relationships in situ, forming hypotheses, and then testing these 

hypotheses in a laboratory setting, under closely controlled and monitored conditions. As 

long as laboratory conditions faithfully replicate natural in situ conditions, then the 

inverse becomes a valid approach; laboratory observations and experiments can generate 

new hypotheses that can be tested by field observations (Murray, et.al. 2004). 

In 2002, a system of large aquaria (mesocosms) were constructed at the U.S. 

Geological Survey, Leetown Science Center (LSC) in Leetown, West Virginia, in order 

to conduct experiments that test our field hypotheses and reproduce scenarios commonly 

found in the estuaries and marine ecosystems of South Florida. These aquaria allow us to 

test the effects of natural stressors, for example, salinity and temperature extremes, on 

flora and fauna typical of South Florida’s estuaries, and shallow marine basins. The 

results of salinity and temperature experiments on selected mollusks are the subject of 

this report. These experimental data expand our understanding of the living biota, and 

therefore, our ability to interpret the historical data from cores. 

The Natural Setting 

Florida Bay is a reticulate system of mud banks and small keys or islands 

predominantly covered by red mangrove (Rhizophora mangle) that enclose over 40 

shallow basins or depressions (Figure 1). The water depth in these basins ranges between 

two and six feet, and the mudbanks are often emergent during low tides (McPherson and 

Halley, 1996). This network of banks and islands limits the tidal variation and exchange 

of water from basin to basin. Restricted exchange of water coupled with the limited 

influx of freshwater can cause areas within Florida Bay to have large fluctuations in 

salinity, temperature, and nutrient content. In addition, one basin can be very different in 

terms of salinity and temperature from adjacent basins. Regions within a basin also can 

experience rapid temperature changes, due to the summer heat and evaporation. As the 

evaporation increases, the salinity can increase significantly, especially in shallow, 

localized areas. Conversely, summer thunderstorms can drop temperatures and salinity in 

a very short period of time in localized areas. 

The variability of salinity and temperature within the estuaries of South Florida is 

largely controlled by the seasonal patterns of a sub-tropical climate and by specific storm 

events. Throughout the South Florida region, the typical annual climate cycle consists of 

a cool, dry season and a hot, wet season. The winter months (December to February) 

constitute the cool, dry season, which has an average seasonal temperature of 70.33°F 

and an average rainfall of 5.32 inches (Figure 2A-B) in the Key West, FL area. During 

the hot, wet summer months (June through August) the average seasonal temperature is 
Winter (Dec-Feb) 1896 - 2005 Average = 70

Winter (Dec-Feb) 1896 - 2005 Trend = 0.09 

Figure 2A. Winter temperature average for the Key West area of South FloridaGraph from the NOAA website, http://www.ncdc.noaa.gov/oa/climate/research/cag3/cag3.htmlLast visited on 11/29/05
Figure 2B. Winter precipitation average for the Key West area of South Florida.

Graph from the NOAA website, http://www.ncdc.noaa.gov/oa/climate/research/cag3/cag3.htmlLast visited on 11/29/05

Winter (Dec-Feb) 1896 - 2005 Average = 5.32 InchWinter (Dec-Feb) 1896 - 2005 Trend = 0.08 Inches 
6

83.26°F and the average rainfall is 12.79 inches (Figure 3A-B). Typically, winter months 

are characterized by reduced freshwater runoff in the near shore environments and drier 

conditions in the Everglades. This reduction in runoff and direct rainfall on the surface of 

the basin causes salinity to go up while temperature goes down. The warmer summer 

months give rise to common daily rain squalls and stronger events such as hurricanes can 

affect the entire region. These weather events can dump large amounts of freshwater 

both into the terrestrial Everglades and the estuaries, and this influx of rain water can 

reduce the salinity and temperature, in some cases dramatically. 

Along the terrestrial margins of the estuaries, this seasonal variability is the 

primary driver of salinity and temperature fluctuations. Salinities along the terrestrial 

margins (Figure 4) vary from nearly fresh (4.8 ppt) from June through November, slowly 

increasing to nearly marine salinities (30.65 ppt) from December through May. The 

reticulate system of banks within Florida Bay can cause the salinity in restricted basins to 

exceed 40 ppt and temperatures to exceed 30° C. Figure 5 illustrates the variation of 

salinities in different basins. These cycles of salinity and temperature change create a 

rigorous environment for the organisms living there. 

Experimental Design and Purpose 

Experiments on live organisms began in 2002 to fulfill several purposes for 

ecosystem history research. First, a project was started in 2001 to examine the utility of 

using molluscan shells as recorders of change in water chemistry parameters, primarily 

salinity. This work is briefly summarized in Stamm and Wingard (2004) and will be the 

subject of future reports. In order to use shells as recorders of change, however, we 

needed to understand their life histories and their ecology. When did the shells grow – 

year round or seasonally? Did they grow continuously throughout their life span or did 

growth rates slow? Did growth stop during certain environmental events, such as high 

salinity or temperatures? Second, observations on living mollusks in the field were only 

obtained periodically. (For Florida Bay, generally two times per year, once in the wet 

season and once in the dry season.) Consequently, we frequently missed obtaining 

critical biotic data associated with salinity or temperature extremes tolerated by living 

mollusks. These data are necessary to better understand the effects of salinity, 

temperature and other water chemistry parameters on the reproduction, growth and 

overall survivability of key species of mollusks. Field data alone did not provide us with 

a complete proxy data set for interpreting the downcore assemblages we are analyzing as 

part of the Ecosystem History projects or for addressing questions associated with the 

shell chemistry study. . 

In order to address the needs of ecosystem history research, several experiments 

were designed. The experimental systems were utilized in this study to quantify the 

mortality of selected mollusks due to extremes in salinity and temperature that have been 

recorded in Florida Bay (Figure 6). The recorded high and low values of salinity and 

temperature were used to set the limits for the experimental values. Early tank 
Summer (Jun-Aug) 1895 - 2005 Averag

Summer (Jun-Aug) 1895 - 2005 Trend 

Figure 3A. Summer temperatures for the Key West area of South Florida.Graph from the NOAA website, http://www.ncdc.noaa.gov/oa/climate/research/cag3/cag3.htmlLast visited on 11/29/05
Summer (Jun-Aug) 1895 - 2005 Average = 1

Summer (Jun-Aug) 1895 - 2005 Trend = 0.24 

Figure 3B. Summer precipitation for the Key West area of South FloridaGraph from the NOAA website, http://www.ncdc.noaa.gov/oa/climate/research/cag3/cag3.htmlLast visited on 11/29/05
Daily Salinity at Little Madeira

0

5

10

15

20

25

30

35

40

8/7/1993

2/7/1994

8/7/1994

2/7/1995

8/7/1995

2/7/1996

8/7/1996

2/7/1997

8/7/1997

2/7/1998

8/7/1998

2/7/1999

8/7/1999

Minimum

Maximum

Figure 4. Salinity at the Little Madeira water monitoring site, Florida Bay,.

Data compiled and graphed by Robert Stamm, USGS

Salinity in ppt
0

10

20

30

40

50

60 Rabbit Key Basin

Terrapin Bay

Park Key

Joe Bay

Little Madiera Bay

Twin Key Basin

Whipray Basin 1 4 -A u g -0 1 0 5 -S e p -0 1

2 7 -Ju n -8 9 2 2 -A u g -8 9 2 5 -Ju l-8 9 0 8 -N o v -8 9 0 8 -D e c -8 9 0 1 -Ja n -9 0 0 1 -F e b -9 0 0 1 -M a r-9 0 0 1 -A p r-9 0 1 1 -A p r-9 0 0 1 -M a y -9 0 0 1 -Ju n -9 0 0 1 -Ju l-9 0 0 1 -A u g -9 0 0 2 -Ju l-9 0 2 0 -A u g -9 0 0 1 -S e p -9 0 0 1 -O c t-9 0 0 1 -N o v -9 0 0 1 -D e c -9 0 0 1 -Ja n -9 1 0 1 -F e b -9 1 0 1 -M a r-9 1 1 4 -M a r-9 1 1 6 -A p r-9 1 0 1 -M a y -9 1 1 1 -Ju n -9 1 0 9 -Ju l-9 1 1 1 -S e p -9 1 3 0 -Ju l-9 1 0 9 -O c t-9 1 1 3 -N o v -9 1 0 4 -D e c -9 1 1 5 -Ja n -9 2 1 1 -F e b -9 2 1 0 -M a r-9 2 2 2 -A p r-9 2 1 3 -M a y -9 2 1 7 -Ju n -9 2 1 2 -A u g -9 2 1 5 -Ju l-9 2 0 8 -S e p -9 2 1 3 -O c t-9 2 1 0 -N o v -9 2 0 1 -D e c -9 2 2 0 -Ja n -9 3 0 9 -F e b -9 3 0 9 -M a r-9 3 0 6 -A p r-9 3 1 1 -M a y -9 3 0 2 -Ju n -9 3 0 3 -A u g -9 3 0 6 -Ju l-9 3 0 8 -S e p -9 3 0 5 -O c t-9 3 0 2 -N o v -9 3 0 1 -D e c -9 3 1 0 -Ja n -9 4 0 1 -F e b -9 4 0 8 -M a r-9 4 0 5 -A p r-9 4 0 3 -M a y -9 4 0 7 -Ju n -9 4 0 2 -A u g -9 4 0 6 -Ju l-9 4 1 3 -S e p -9 4 0 4 -O c t-9 4 0 1 -N o v -9 4 2 1 -N o v -9 4 3 0 -N o v -9 4 0 4 -Ja n -9 5 0 1 -F e b -9 5 0 1 -M a r-9 5 1 8 -A p r-9 5 2 3 -M a y -9 5 2 0 -Ju n -9 5 1 0 -A u g -9 5 1 1 -Ju l-9 5 0 7 -S e p -9 5 1 9 -O c t-9 5 1 6 -N o v -9 5 1 3 -D e c -9 5 2 3 -Ja n -9 6 1 2 -F e b -9 6 2 2 -M a r-9 6 2 5 -A p r-9 6 1 0 -M a y -9 6 0 6 -Ju n -9 6 2 2 -A u g -9 6 0 4 -Ju l-9 6 1 4 -S e p -9 6 1 5 -O c t-9 6 0 7 -N o v -9 6 0 5 -D e c -9 6 0 8 -Ja n -9 7 1 5 -F e b -9 7 1 2 -M a r-9 7 1 6 -A p r-9 7 2 2 -M a y -9 7 1 1 -Ju n -9 7 2 0 -A u g -9 7 1 0 -Ju l-9 7 1 0 -S e p -9 7 2 1 -O c t-9 7 2 5 -N o v -9 7 1 2 -D e c -9 7 2 1 -Ja n -9 8 1 8 -F e b -9 8 2 0 -M a r-9 8 1 5 -A p r-9 8 1 4 -M a y -9 8 1 0 -Ju n -9 8 1 9 -A u g -9 8 1 4 -Ju l-9 8 1 7 -S e p -9 8 3 0 -S e p -9 8 0 3 -N o v -9 8 0 1 -D e c -9 8 1 0 -F e b -9 9 2 3 -M a r-9 9 2 9 -A p r-9 9 2 8 -M a y -9 9 1 7 -Ju n -9 9 2 4 -A u g -9 9 0 6 -Ju l-9 9 2 3 -S e p -9 9 2 6 -O c t-9 9 1 2 -N o v -9 9 0 3 -D e c -9 9 2 5 -Ja n -0 0 2 8 -F e b -0 0 2 1 -M a r-0 0 1 4 -A p r-0 0 3 0 -M a y -0 0 2 0 -Ju n -0 0 2 9 -A u g -0 0 2 0 -Ju l-0 0 2 9 -S e p -0 0 2 6 -O c t-0 0 3 0 -N o v -0 0 1 1 -D e c -0 0 2 5 -Ja n -0 1 2 1 -F e b -0 1 0 6 -M a r-0 1 0 3 -A p r-0 1 0 2 -M a y -0 1 0 5 -Ju n -0 1 1 2 -Ju l-0 1

1 /1 9 9 0 1 /1 9 9 1 1 /1 9 9 2 1 /1 9 9 3 1 /1 9 9 4 1 /1 9 9 5 1 /1 9 9 6 1 /1 9 9 7 1 /1 9 9 8 1 /1 9 9 9 1 /2 0 0 0 1 /2 0 0 19 /2 0 0 1

1989 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 1990

Florida Bay Salinity

Salinity, ppt

EVERGLADES NA EVERGLADES NATIONAL P ARK

Florida Bay

Biscayne

Bay

Gulf of

Mexico

Atlantic Ocean

Joe Bay

Little Madiera Bay

Terrapin Bay

Park Key

Twin Key

Basin Salinity Monitoring Sites

Water Depth

Rabbit Key

Basin

Whipray Basin

0 5 10

Miles

> 3 feet

< 3 feet

Figure 5. Salinity oscillations for the years 1989 to 2001. 

The blue band indicates typical marine salinities for the 

South Florida region. All locations are shown on the 

satellite map.
Figure 6. Historical salinity data for Florida Bay. (Unpublished data set by M. Robblee, USGS. 

Graphed by Joel Hudley, USGS

0

10

20

30

40

50

60

70

80

55 60 65 70 75 80 85 90 95

 Years 1955-1995

Salinity in PPT
7

experiments conducted in Reston, Virginia from August 2000 until January 2003 (three 

experimental attempts), were all determined to be unsuccessful due to power failures that 

caused the water chemistry collapse in the experimental systems. 

This report describes the results of the experiments conducted in order to 

determine the tolerance of nine key molluscan species to a broad range of salinity and 

temperature. The results supplement our field data by allowing us to extend the 

minimum and maximum values observed in the field, and to determine mortality and 

reproductive viability under atypical conditions. These data provide improved proxy data 

for interpreting historical salinity patterns preserved in the faunal assemblages in the 

sediment cores examined for the ecosystem history research projects. 

Additional experiments and observations are ongoing in habitats established in 

Florida Bay in the winter of 2001 (under Everglades National Park Study #EVER-00141; 

and Permits 2000-004; EVER-2001-SCI-0048; EVER-2002-SCI-0038; EVER-2003-SCI0053; EVER-2004-SCI-0099). The habitats were specifically designed to test growth and 

survivability in situ over an extended period of time, under varying environmental 

conditions of the pelecypod, Chione cancellata; this species was selected as the test 

organism for shell chemistry studies. These habitats also provide a control for the overall 

health and success of the mesocosms at LSC, i.e. if the C. cancellata in both locations are 

equally healthy, then the mesocosms are an accurate replicate of Whipray Basin, Florida. 

Details of the habitat work will be published in a separate report, but relevant to the 

mesocosm experiments was the environmental data from the two habitats in Whipray 

Basin (Figure 7), near water monitoring station FB21. The water monitoring stations 

were established by Everglades National Park and South Florida Water Management 

District. The data from the water monitoring station provided a template for reproducing 

the natural water chemistry conditions in the mesocosms at Leetown Science Center. 

Nine molluscan species, representing eight genera, were selected for the 

experimental trials. These species are commonly found in our modern site surveys and in 

the cores examined for the ecosystem history studies. In addition, these were species that 

were relatively easy to find and collect in the field, survive transport back to Leetown, 

and were not known to be particularly selective about ecological requirements such as 

food source, small fluctuations in water chemistry, or substrate.

MESOCOSMS 

The experimental aquatic culture systems (mesocosms) at Leetown Science 

Center were designed to replicate mesohaline to hypersaline ecosystems typical of South 

Florida estuaries. Two large (System A 2750 gallons and System B 2000 gallons) 

mesocosms were designed to replicate communities of seagrass beds and more open 

bottom environments; these were used for observation, culture and an experimental 

control system (Figure 8). Experimental systems were allowed to equilibrate for six 

months before the actual experimental cycles began. This process allowed the microbial, 

algal, animal, and plant communities to become established and stabilized before 

experiments began. Eight separate systems (220 gallons each) were constructed for the 

experiments. Both the experimental and the control systems were designed so that 

multiples of any experiment could be conducted simultaneously within the same system. 
Everglades National Park

Florida Bay

Biscayne

Bay

Gulf of

Mexico

Atlantic Ocean

Joe Bay

Little Madiera Bay

� errapin Bay

Habitat Location

� � � � � �� � � � �

Whipray Basin

� � � �

Miles

> 3 feet

< 3 feet

Figure 7. Top, map showing location of 

habitats in Whipray Basin. Middle, Images 

of habitats, taken August 2004. Bottom, 

Image of habitat as originally installed
� � � � � � �� � � � � �

�������� � � � �

� � � � � � � � � �� �

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� � � � � � ��� � � � � � ��

� � � � � �� � ��� � �

Species

Tank

� � � �

� � � � � � ��� � � � � � ��

� � � � � �� � ��� � �

Seagrass

Tank

Seagrass

Tank

� � � �

� � � � �� � � �

� � � � �� � � � � �� � � � � ��� � � � � � �� �� � � �� � ��� � �

� � � � � � ��� � � �

���������� � � �

� � � � � �� � � � �

Species

Tank

� � � � � � � �� � � �

Figure 8. Schematic of the Leetown Science Center Mesocosms, showing main systems and 

experimental systems.
8

The LSC mesocosms are composed of eleven separate flow-through circulating 

systems totaling more than eleven thousand gallons (Figure 9A-B). The mesocosms are 

situated within a 20,000 square foot greenhouse, which provides natural sunlight and a 

solar and lunar cycle similar to that found in Florida Bay. The systems at the LSC are 

monitored for water chemistry parameters, temperature, salinity, and light intensity 

(Figure 10) and these data are compared with data from water monitoring stations and 

other modern monitoring sites in Florida Bay. The combination of modern sampling site 

data and high frequency observations made at the Whipray habitats provide a scale by 

which the overall health of the LSC mesocosms can be measured and monitored. 

Each system has a large sump tank, which is utilized as a refugium. A refugium 

tank is commonly used in the aquaculture industry for several reasons; protection from 

predation, increase the overall water volume, food source cultivation, plant growth for 

natural nitrate reduction, etc. The refugia tanks in the LSC system serve multiple 

functions. 1) These tanks provide a buffer for the system by increasing the overall 

volume of water so that any changes in water chemistry, temperature, etc. would be 

gradual and not create unwanted stress on the organisms. 2) When adding water to 

compensate for evaporation, and/or adding chemical components that are taken up by the 

marine organisms, the sump tanks provide a mixing and equilibration area so that 

dramatic changes to the system are reduced. 3) They provide an integrated part of the 

system where any monitors, control instruments, bio-filters etc. can be placed and not 

have a direct effect on organisms in the habitat part of the systems. 1 4) The refugia add 

stability because water parameter changes are more subtle as the overall mesocosm 

volume increases. The effect of unexpected problems such as pump and temperature 

control system shut-downs due to power outages is reduced with a large refugium. The 

only mechanical filters on the mesocosms are small protein skimmers that are used to 

remove heavy proteins and provide better gas exchange. The system is primarily 

maintained through natural bio-filtration carried out by the plant and animal assemblages 

in each system. The systems were designed in a gravity flow layout so that any power 

failure effects were minimized and no water loss would occur. This layout also allows 

the system to self start when power is restored. 

The substrate in all systems is naturally occurring Halimeda hash (Figure 11). 

This medium provides a large surface area for microbial communities, which are 

necessary for the nitrogen-reduction cycles. Halimeda hash is biogenically created so as 

it dissolves it provides the trace-elements and metals (calcium, magnesium, strontium, 

etc.) typically present in seawater. These components are necessary for calcium 

carbonate production during growth of the organisms. In addition, the calcium carbonate 

composition of the Halimeda hash provides a pH buffer for the systems. 

In order to provide adequate food, commercially available phyto-plankton and 

zooplankton mixtures are added to the tanks as food sources for the suspension feeding 

 1

 Originally, the sump tanks were not intended to contain any of the study 

organisms, but they have inadvertently become part of the biological system as plants or 

animals in the main tanks reproduced and the offspring spread into the sump tanks. 
Florida Bay North – Experimental Systems at Leetown Science Center, WVA

System A: 2750 gal.

System B: 2000 gal.

8 Experimental Systems:

210 gal. each

8 Experimental Systems:

210 gal. each

Wave Tank

Figure 9. View showing tanks in the greenhouse at the LSC 
15.00

20.00

25.00

30.00

35.00

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45.00

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Tem

perature in

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WB Salinity

WB Temperature

LSC Salinity

LSC Temperature

Figure 10. Comparison of Leetown Science Center (LSC) mesocosms with Whipray Basin (WB) Salinities and temperatures.

Whipray Basin data is combination of USGS and SFWMD monitoring data.
Figure 11. Picture of LSC tank floor showing substrate and various organisms.

Photo by JBM
9

organisms in the system. Establishing epiphytic growth on the tank walls and plant 

assemblages was essential prior to starting any experimental studies because this provides 

the primary food source for grazing animals. 

The mesocosms were monitored for water chemistry parameters using both wet 

chemistry methods and electronic instruments. Wet chemistry monitoring used 

commercially available titration kits to quantify strontium, calcium, iodine, alkalinity, 

and magnesium. The accuracy range was within 5-15 ppt for any metal measured 

depending on the titration method. Electronic probes were used to monitor salinity, 

temperature, pH, and dissolved oxygen; these were the same instruments used in the field 

to monitor in situ conditions. Temperature and light were monitored using separate data 

loggers that gather data in thirty minute intervals; these data loggers also were placed on 

the habitats in Whipray Basin (set at 180 minute intervals). These data gave a high 

resolution comparison of temperature and light between the laboratory and the in situ

ecosystems (Figure 12). 

The synthetic sea water used in the LSC mesocosms was made using multiple 

brands of common commercial aquaculture sea salt mixtures. Freshwater added to the 

commercial mixtures was a combination of deionized water and LSC well water. The 

well water has high calcium content and low nitrate levels so it was ideal for making 

synthetic sea water. Before adding newly mixed sea water to the systems, each batch was 

allowed to equilibrate so that pH changes would be subtle. New sea water was added to 

the refugia tanks so that the initial mixing was outside the habitat tanks. The fresh water 

used in the new sea water was a combination of deionized water and LSC well water. 

Organisms were initially introduced into systems A and B at 35 ppt and 25oC and 

were allowed to equilibrate for six months before experiments began. Four experiments 

were conducted simultaneously in four separate 220 gallon experimental systems: 

1. System 1 experiments: Increasing salinity with relatively stable high 

temperature (at or above 32o

C) -- analogous to summer conditions when 

evaporation exceeds rainfall. 

2. System 2 experiments: Increasing salinity with relatively stable low 

temperatures (at or below 17o

C) -- analogous to winter dry conditions when 

the humidity is low and winds cause accelerated evaporation. This is seen in 

historical NOAA (National Data Buoy System 

http://www.ndbc.noaa.gov/station_page.php?station=LONF1 -) data for 

rainfall, wind direction and speed, and salinity. 

3. System 3 experiment: Decreasing salinity with relatively stable high 

temperature (at or above 32o

C) – analogous to summer conditions during a wet 

year when rainfall exceeds evaporation or when freshwater input is driven by 

rainfall in adjacent regions. This added freshwater provides a point source 

(canal mouth) stress to the organisms in the region. 

4. System 4 experiment: Decreasing salinity with relatively stable low 

temperatures (at or below 17oC) -- analogous to winter season when rainfall 

equals or exceeds evaporation, and point source influence during the cooler 

winter months. 

Salinity and temperature was altered gradually, in each experimental system from the 

starting point of 35 ppt and 24 o

C over a period of 90 days and maintained at that level 

until none of the original test mollusks were remaining alive (Table 1). A control tank of 
 10

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1/9/04

1/24/04

2/8/04

2/23/04

3/9/04

3/24/04

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5/8/04

Whipray A water

Whipray B water

System A water

T

e

m

p

e

r

a

t

u

r

e

Figure 12. Comparison of Leetown mesocosm temperature to Whipray Basin water temperatures.
10

the same design and size as the experimental tanks was housed within system A (Figure 

8) and was maintained at average marine salinity (32-35 ppt) and temperature (24-26oC). 

RESULTS 

The experiments began on September 23, 2003 and continued for 210 days ending 

on April 19, 2004. At that time none of the original individuals from nine species, (eight 

genera), remained alive in the experimental systems, however there were individuals 

alive in the control system at this time. The systems were then maintained at the final 

salinity and temperature so that follow-up observations could be made on any offspring 

that were noted. Table 1 shows the duration of the experiments, and the final salinities 

obtained when all starting individuals were dead. Table 2 shows the duration of groups 

based on hyper/hypo saline systems. The following results are organized alphabetically 

by species and explain the response of each species to the four experiments. The salinity 

levels for each experiment are in parts per thousand (ppt) and all temperatures are in 

degrees Centigrade. The levels indicated are the final averages (FA), i.e. the, last ten 

days’ average of the measurements, prior to the death of the last individuals (of a given 

species) in each experimental system. The high/low salinity systems are referred to as 

the hypersaline/hyposaline systems respectively. 

Brachidontes exustus: B. exustus is commonly found throughout Florida Bay, in 

a wide range of salinities and temperatures, and is often seen in dense groupings. The 

individuals in the hypersaline, high temperature System 1 (FA 59 ppt and 31°C) survived 

for 181 days, with no juveniles observed. Individuals in the high saline low temperature 

System 2 (FA 57 ppt and 15°C) survived for 159 days and no juveniles were seen (Figure 

13A). Individuals placed in the hyposaline, high temperature System 3 (FA 16 ppt, and 

33°C) survived for 154 days and no offspring were observed. The individuals in low 

salinity and low temperature, System 4, (FA 18 ppt and 17oC) survived for 149 days and 

no offspring were observed. (Figure13B) B. exustus individuals in the control system 

were alive more than 180 days beyond the termination of the experimental phase and 

have reproduced effectively. 

Bulla striata: B. striata is often seen live and is abundant as pristine shell debris 

from the marginal areas (regions near the Everglades/ Florida Bay interface) of Florida 

Bay. The experimental results confirm the resilience of B. striata to a broad range of 

salinity and temperature values. B. striata individuals survived for 180 days in increasing 

salinity and increasing temperature System 1, (FA 58 ppt and 31°C), with juveniles 

observed in the system on 2/18/2004. The individuals in the increasing salinity and 

decreasing temperature System 2 (FA 58ppt and17.51°C) survived for 175 days with 

juveniles recorded on 12/22/2003 (Figure 14A). The hyposaline higher temperature 

individuals System 3, (FA 19 ppt and 33°C) were alive for 131 days with no juveniles 

seen. The individuals in the hyposaline, low temperature System 4, (FA 16 ppt and 

18°C) survived for 159 days with no juveniles found (Figure 14B). Seventy percent of 

the original individuals were alive in the control system at the termination of the 

experiment. Reproduction in the control system was observed in large numbers. B. 

striata was resilient across the experimental range and had an abundance of juveniles 
Table 1. Salinity and temperature data for experimental systems

Date 

Experiment 

Initiated

Date 

Experiment 

Terminated

Duration in 

Days

Minimum 

ppt

Maximum 

ppt

Average 

ppt

Minimum 

Temperature

M

Tem

System A 

Co

ntrol 9/22/2003 N/A ongoing 38 30 33.97 18.85 

System 1 

High Salinity / High 

Tem

perature 9/22/2003 4/11/2004 202 31 63 49 14.97 

System 2 

High Salinity / Low 

Tem

perature 9/22/2003 3/17/2004 178 30 63 47 13.61 

System 3 

Low Salinity / High 

Tem

perature 9/22/2003 2/22/2004 155 13 35 25 16.4 

System 4 

Low Salinity / Low 

Tem

perature 9/22/2003 2/28/2004 160 14 35 24.26 13.76 
Table 2. Duration data for the experimental systems. 

Survival is in days for individual species in each of the experimental systems

System 1 System 2 System 3 System 4 System 1 Syste

Species

Starting # 

of 

Individuals 

of this 

species

Total 

survival 

days for 

all 

species

Hypersaline 

systems, 

Total 

Survival 

Days

Hyposaline 

systems, 

Total 

Survival 

Days

Maximum # 

of days 

individuals 

survived by 

species

Maximum # 

of days 

individuals 

survived by 

species

Maximum # 

of days 

individuals 

survived by 

species

Maximum # 

of days 

individuals 

survived by 

species

Juveniles 

observed 

during the 

experimental 

trials

Juven

obser

during 

experim

trial

Brachidontes exustus 20 643 340 303 181 159 154 149 no no Bulla striata 10 645 355 290 180 175 131 159 yes yes Cerithium sp. cf. eberneum 5 457 269 188 149 120 96 92 no no Cerithium muscarum 20 683 372 311 200 172 152 159 yes yes Chione cancellata 10 586 303 283 161 142 139 144 no no Columbella rusticoides 10 540 327 213 186 141 124 89 no no Modulus modulus 20 655 362 293 190 172 152 141 no yes Prunum apicinum 5 466 278 188 191 87 131 57 no no Turbo castanea 10 403 217 186 124 93 122 64 no no 
0

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Figure 13A. Brachidontes exustus % remaining alive within the experimental systems. 

Temperature in Degrees C Temperature in Degrees C

9/22/200310/6/200310/20/200311/3/200311/17/200312/1/200312/15/200312/29/20031/12/20041/26/20042/9/20042/23/20043/8/20043/22/20044/5/20044/19/2004

Temperature in Degrees C

Salinity in ppt Salinity in ppt

Salinity in ppt

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9/22/200310/6/200310/20/200311/3/200311/17/200312/1/200312/15/200312/29/20031/12/20041/26/20042/9/20042/23/20043/8/20043/22/20044/5/20044/19/2004

Control tank within System A 

Experimental System 1

Experimental System 2

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Starting # Brachidontes exustus =20

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Figure 13B. Brachidontes exustus % remaining alive within the experimental systems. 

Temperature in Degrees C Temperature in Degrees C

9/22/200310/6/200310/20/200311/3/200311/17/200312/1/200312/15/200312/29/20031/12/20041/26/20042/9/20042/23/20043/8/20043/22/20044/5/20044/19/2004

Temperature in Degrees C

Salinity in ppt Salinity in ppt

Salinity in ppt

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9/22/200310/6/200310/20/200311/3/200311/17/200312/1/200312/15/200312/29/20031/12/20041/26/20042/9/20042/23/20043/8/20043/22/20044/5/20044/19/2004

Control tank within System A 

Experimental System 3

Experimental System 4

Starting # Brachidontes exustus =20

Starting # Brachidontes exustus =20

salinity sys 3

Temperature in deg.C

Starting # Brachidontes exustus =20

salinity sys 4

Temperature in deg.C

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Temperature in Degrees C Temperature in Degrees C

9/22/200310/6/200310/20/200311/3/200311/17/200312/1/200312/15/200312/29/20031/12/20041/26/20042/9/20042/23/20043/8/20043/22/20044/5/20044/19/2004

Temperature in Degrees C

Salinity in ppt Salinity in ppt

Salinity in ppt

Control tank within System A 

Experimental System 1

Experimental System 2

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Figure 14A. Bulla striata % remaining alive within the experimental systems. 

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Starting # Bulla striata =10

Starting # Bulla striata =10
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Figure 14B. Bulla striata % remaining alive within the experimental systems. 

Temperature in Degrees C Temperature in Degrees C

9/22/200310/6/200310/20/200311/3/200311/17/200312/1/200312/15/200312/29/20031/12/20041/26/20042/9/20042/23/20043/8/20043/22/20044/5/20044/19/2004

Temperature in Degrees C

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Salinity in ppt

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9/22/200310/6/200310/20/200311/3/200311/17/200312/1/200312/15/200312/29/20031/12/20041/26/20042/9/20042/23/20043/8/20043/22/20044/5/20044/19/2004

Control tank within System A 

Experimental System 3

Experimental System 4

salinity sys 3

Temperature in deg.C

salinity sys 4

Temperature in deg.C

Starting # Bulla striata =10

Starting # Bulla striata =10

Starting # Bulla striata =10

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11

appearing in the hyper-salinity tanks within 150 days. Salinities when the juveniles were 

first seen were 45-50 ppt, and these new individuals remain in the systems one year later. 

Cerithium sp. cf. C. eburneum: C. sp. cf. C. eburneum is more commonly found 

in the outer estuarine to marine waters where salinity and temperature extremes are less 

frequent. As expected, this species had a relatively low tolerance for changes in salinity 

and temperature. All of the original test individuals were dead within 149 days in the 

hypersaline, high temperature System 1 (FA 50 ppt and 28°C) with no reproduction 

observed. The individuals in hypersaline low temperature System 2 (FA 38 ppt and 

18°C) survived for 120 days and no offspring were observed (Figure 15A). The 

hyposaline high temperature System 3 (FA 25 ppt and 28°C) individuals survived for 96 

days with no offspring seen. The individuals in the hyposaline, decreasing temperature 

System 4 (FA 25 ppt and 18°C) survived 92 days with no juveniles observed (Figure 

15B). The control system also lost most of the original individuals (possibly due to a 

temperature spike causing stress on 12/22/03. There were, however, juveniles seen in the 

control system on 01/14/2004 and 3/17/2004. The offspring are still present and growing 

one year later. 

Cerithium muscarum: C. muscarum proved to be very resilient in all trial 

scenarios. The individuals in the hypersaline, high temperature System 1 (FA 62 ppt, and 

34°C), survived for 200 days, and juveniles were observed throughout the experimental 

system by 1/30/2004. The juveniles remain in the system one year later and are 

reproducing as well. The individuals that were placed in the hypersaline, low 

temperature System 2 (FA 57 ppt, and 17°C) survived for 172 days, and juveniles were 

observed in the system on 1/26/2004 and remain in the system one year later (Figure 

16A). The hyposaline, high temperature System 3 (FA 17 ppt, and 33°C) individuals 

survived for 152 days and no juveniles were observed. The individuals placed in the 

hyposaline, low temperature System 4 (FA 16 ppt, and 16°C) survived for 159 days with 

no reproduction observed (Figure 16B). Sixty five percent of the original individuals 

remained alive in the control system at the termination of the experiment. C. muscarum

has been observed in a wide range of salinities and temperatures in situ so these results 

were not unexpected; however, the proliferation and resilience of the offspring 

throughout all of the tanks within a system, including the refugia was unexpected. 

Chione cancellata: C. cancellata is found commonly throughout Florida Bay and 

surrounding marine waters. These experiments were in large part designed to determine 

the range of salinity tolerance of C. cancellata. The individuals in the hypersaline, high 

temperature System 1 (FA 57 ppt and 31°C) survived for 161 days and no juveniles were 

seen. The hypersaline low temperature System 2 (FA 53 ppt and 16°C) individuals were 

alive for 142 days with no offspring found (Figure 17A). The individuals in the 

hyposaline high temperature System 3 (FA 19 ppt and 31°C) survived for 139 days and 

no juveniles were found. The individuals in the hyposaline low temperature System 3 

(FA 20 ppt and 15°C) survived for 144 days with no juveniles observed (Figure 17B). 

Fifty percent of the individuals in the control system, maintained at marine salinities and 

temperatures, survived beyond the completion of the experimental phase. 

Columbella rusticoides: C. rusticoides is found throughout Florida Bay and into 

the surrounding obligate marine regions. While the number of individuals observed in 

situ is limited, this species has been observed in a range of salinities and temperatures. 

The individuals in the hypersaline, high temperature System 1 (FA 61 ppt, and 32°C) 
0

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9/22/200310/6/200310/20/200311/3/200311/17/200312/1/200312/15/200312/29/20031/12/20041/26/20042/9/20042/23/20043/8/20043/22/20044/5/20044/19/2004

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Salinity in ppt

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9/22/200310/6/200310/20/200311/3/200311/17/200312/1/200312/15/200312/29/20031/12/20041/26/20042/9/20042/23/20043/8/20043/22/20044/5/20044/19/2004

Control tank within System A 

Experimental System 1

Experimental System 2

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Starting # Cerithium

 ebernium =5 

Starting # Cerithium

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Starting # Cerithium

 ebernium =5 

Figure 15A. Cerithium sp. cf. C. eburneum % remaining alive within the experimental systems. 
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Figure 15B. Cerithium sp. cf. C. eburneum % remaining alive within the experimental systems. Temperature in Degrees C Temperature in Degrees C 9/22/2003 10/6/2003 10/20/2003 11/3/2003 11/17/2003 12/1/2003 12/15/2003 12/29/2003 1/12/2004 1/26/2004 2/9/2004 2/23/2004 3/8/2004 3/22/2004 4/5/2004 4/19/2004 Temperature in Degrees C

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Control tank within System A 

Experimental System 3

Experimental System 4

salinity sys 3

Temperature in deg.C

salinity sys 4

Temperature in deg.C

Starting # Cerithium

 ebernium =5 

Starting # Cerithium

 ebernium =5 

Starting # Cerithium

 ebernium =5 

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9/22/200310/6/200310/20/200311/3/200311/17/200312/1/200312/15/200312/29/20031/12/20041/26/20042/9/20042/23/20043/8/20043/22/20044/5/20044/19/2004

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Control tank within System A 

Experimental System 1

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Figure 16A. Cerithium muscarum % remaining alive within the experimental systems. 

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Figure 16B. Cerithium muscarum % remaining alive within the experimental systems. 

Temperature in Degrees C Temperature in Degrees C

9/22/200310/6/200310/20/200311/3/200311/17/200312/1/200312/15/200312/29/20031/12/20041/26/20042/9/20042/23/20043/8/20043/22/20044/5/20044/19/2004

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Control tank within System A 

Experimental System 3

Experimental System 4

salinity sys 3

Temperature in deg.C

salinity sys 4

Temperature in deg.C

Starting # Cerithium

 muscarum =20

Starting # Cerithium

 muscarum =20

Starting # Cerithium

 muscarum =20

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Figure 17A . Chione cancellata % remaining alive within the experimental systems. 

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Figure 17B. Chione cancellata % remaining alive within the experimental systems. 

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Starting # Chione cancellata =10

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12

survived for 186 days with no juveniles found. The hypersaline, low temperature System 

2 (FA 53 ppt, and 16°C) individuals survived for 141 days with no reproduction observed 

(Figure 18A). The individuals placed in the hyposaline, high temperature System 3 (FA 

23 ppt, and 33°C) survived for 124 days with no juveniles found. The hyposaline, low 

temperature System 4 (FA 24 ppt, and 15°C) individuals survived for 89 days with no 

reproduction observed (Figure 18B). Thirty percent of the control system individuals 

survived beyond the close of the experimental phase, and a small group of juveniles were 

observed. 

Modulus modulus: M. modulus is commonly found throughout Florida Bay and 

in widely varying salinities and temperatures. The hypersaline, high temperature System 

1 (FA 61 ppt, and 32°C) individuals survived for 190 days but no offspring were 

observed. The hypersaline, low temperature System 2 (FA 57 ppt, and 17°C) individuals 

survived for 172 days and juveniles were observed throughout the entire system including 

the refugium tank on 2/18/2004 (Figure 19A). The individuals in the hyposaline, high 

temperature System 3 (FA 17 ppt, and 32°C) survived for 152 days with no juveniles 

observed. The hyposaline, low temperature System 4 (FA 21 ppt, and 15°C) individuals 

survived for 141 days with no juveniles observed (Figure 19B). Fully sixty percent of the 

original individuals in the control system were alive at the end of the experimental phase, 

and of these fifty percent were alive over one year later. Juveniles have spread 

throughout the entire system and have been utilized to begin other experiments. 

Prunum apicinum: P. apicinum is a common inhabitant of seagrass beds 

throughout Florida Bay and Biscayne Bay, and has been observed in a range of salinities 

25-45 ppt. The individuals in the hypersaline and high temperature System 1 (FA 60 ppt 

and 33 o C) survived for 191 days and no offspring were observed. The individuals in the 

hypersaline, low temperature System,( FA 49 ppt, and 24oC) survived for 87 days with no 

reproduction observed (Figure 20A). The individuals in the hyposaline, high temperature 

System 3 (FA 20 ppt and 33 o C) survived for 131 days with no reproduction observed. 

The hyposaline, low temperature System 4 (FA 28 ppt and 23oC) individuals survived for 

only 57 days (Figure 20B). Three out of five individuals in the control system survived 

beyond the termination of the experimental phase but reproduction was not observed. 

The die-off of P. apicinum in this experiment may be more due to lack of proper food 

source than to the salinity/ temperature levels at the time of demise. 

Turbo castanea: T. castanea is widely distributed in Florida Bay and in obligate 

marine waters throughout South Florida. It is a good indicator of stable average salinities 

and provides a euhaline comparison to the overall experimental results. The individuals 

in the hypersaline, high temperature System 1 (FA 51 ppt and 29°C) survived for 124 

days, with no observed offspring. The individuals in the hypersaline, low temperature 

System 2 (FA 47 ppt, and 23°C) survived for 93 days with no reproduction observed 

(Figure 21A). The individuals placed in the hyposaline, and high temperature System 3 

(FA 24 ppt, and 34°C) survived for 122 days with no observed reproduction. The 

hyposaline, low temperature System 4 (FA 27 ppt, and 20°C) individuals survived for 64 

days with no juveniles observed (Figure 21B). The control system had a survival rate of 

nine out of the original ten individuals and reproduction in very high numbers. 

Examining the results for all the species in the four experiments, it appears that 

salinities higher than 35 ppt (typical marine) and below 45 ppt have a minimal overall 

effect on the nine species tested (experiments 1 and 2). When the salinity values 
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Figure 18A. Collumbella rusticoides % remaining alive within the experimental systems. 

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Figure 18B. Collumbella rusticoides % remaining alive within the experimental systems. Temperature in Degrees C Temperature in Degrees C 9/22/2003 10/6/2003 10/20/2003 11/3/2003 11/17/2003 12/1/2003 12/15/2003 12/29/2003 1/12/2004 1/26/2004 2/9/2004 2/23/2004 3/8/2004 3/22/2004 4/5/2004 4/19/2004 Temperature in Degrees C

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Figure 19A. Modulus modulus % remaining alive within the experimental systems. 

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13

exceeded the 45 ppt range, however, mortality rates began to increase. Conversely, in the 

lower salinity experiments (3 and 4) a decrease of just 9 ppt from 35 ppt to 26 ppt had an 

immediate effect on the mortality rate in almost all species tested. In contrast to salinity, 

temperature appears to be a secondary stressor in all of the experimental scenarios. In 

experiment 3 and 4 the temperature oscillations within the experimental systems did not 

exceed typical conditions in Florida Bay when the die-off of multiple species began. 

However, rapid temperature changes seen in experimental mesocosms 1 and 2 on 

12/27/2003 in System 1 and 12/29/2003 in System 2 clearly added a level of stress. The 

die-off of several individuals in both Systems 1 and 2 following the rapid temperature 

changes demonstrates the effect that wide range-short duration temperature changes have 

on these species. (Figure 22 of all graphs). These temperature fluctuations are also 

observed in situ and clearly need further experimentation in order to quantify slow 

stressors coupled with rapid change stress.

DISCUSSION 

Almost all ecosystems have a built in resilience and can tolerate change whether it 

is a rapid change of short duration or a more gradual change that is sustained for long 

periods of time. Rapid change will stress a system, sometimes bringing dramatic declines 

in populations, but generally there are enough survivors to re-establish a stressed species, 

as long as the duration of the event is short. Changes over longer, biologically significant 

periods of time, allow an ecosystem to adapt and new or more resilient organisms can fill 

empty niches. The ecosystem in South Florida and in particular Florida Bay has shifted 

away from its natural patterns for the past 50-100 years due to changes in freshwater 

influx. The construction of canals has removed the natural seasonal cycles of freshwater 

sheet flow from the terrestrial Everglades and has led to point-source delivery of 

freshwater. This point source (canal mouth) delivery can cause rapid changes in salinity, 

temperature, and other water quality parameters. Rapid changes that are maintained for 

extended periods of time do not allow the organisms to adapt or to migrate and large dieoffs can occur, which in turn lead to significant changes in water chemistry as nutrients 

from decaying organic matter are released. These changes can create a negative feedback loop as added nutrients can cause additional die-offs. 

The experimental results presented here have demonstrated that changes in 

salinity and/or temperature can cause polyhaline organisms to be stressed beyond the 

limits of recovery, for example in the decreasing salinity systems no reproduction was 

observed in any system. This loss will inevitably lead to a change in the community 

composition that is found within the affected areas, beginning with a reduction in overall 

diversity especially in environments where only the resilient euryhaline species can 

survive. Our field observations (unpublished data: 

http://sofia.usgs.gov/exchange/flaecohist/) indicate this loss of diversity has already 

happened in the vicinity of Taylor Creek and Trout Creek outflow where we find a 
14

predominance of Brachidontes exustus and Cerithium muscarum. When the plant and 

invertebrate populations are stressed beyond recovery, the overall effect can be farreaching as these organisms form the base of the food chain for most of the other 

inhabitants of these regions. These estuaries also serve as large nurseries for many 

marine fish and invertebrate species. 

By combining data from the LSC experiments and from ongoing Ecosystem 

history research, molluscan species can be identified as indicator species to measure the 

overall health of South Florida estuaries, particularly Florida Bay. Indicator species of 

minor or short term changes that exceed seasonal variation and are commonly found 

throughout the Florida Bay region include Modulus modulus and Brachidontes exustus. 

These two species are relatively abundant and easily found alive and in debris samples, 

but as the experiments have shown, have a lower tolerance to water changes just beyond 

the typical range of seasonal variation. Indicators of sustained, large scale changes 

include Cerithium muscarum, and Bulla striata. These two species appear to have a 

strong resilience during changes in salinity and temperature beyond the typical range of 

seasonal variation, but beyond which survival is extremely limited. These observations 

are confirmed by our modern field observations and collections from Florida Bay, taken 

since 1995 (unpublished data http://sofia.usgs.gov/exchange/flaecohist/) The offspring 

produced by both C. muscarum and B. striata were able to survive for more than three 

months in the higher salinities and began to show rapid growth when the experimental 

tanks were slowly returned to typical seasonal ranges of salinity and temperature. 

The emphasis of the experiments was on salinity and temperature; however, we 

observed the impact of other factors on the study species. Prunum apicinum and 

Columbella rusticoides have more specific food source needs than the epiphytic grazing 

species in this experiment and did not survive throughout the range of salinities that have 

been observed in situ. Subsequent observations have shown that P. apicinum will prey 

on smaller gastropods and is a very aggressive carrion feeder with response time to food 

source introduction measured in seconds to minutes over the total tank area. When 

provided with adequate food sources P. apicinum will survive and flourish in our 

systems. The food source supply problems also may have affected Brachidontes exustus. 

B.exustus that were introduced into System B have shown good resilience and 

reproduction in part due to overfeeding designed to stimulate an increase in nutrients. 

Subsequent observations show that B. exustus will thrive when a range of phyto-plankton, 

pico-plankton and large algal mats, primarily Phaeophytes and filamentous Chlorophytes 

are present in the system. These observations have been seen both in situ and in our 

mesocosms. Eutrophication of the water column will often lead to pico/phyto plankton 

blooms that may explain the dispersal of B. exustus in the Bay waters. Turbo castanea,

being obligate marine, survived well in the control system but did not survive well in any 

experimental scenarios. 

Chione cancellata proved to be a relatively resilient species across the range of 

experiments as expected because it is observed alive throughout Florida Bay. This 

experimental phase was used to define the overall range of tolerance and to begin to 

quantify the outside limits of the salinity and temperature range for C. cancellata. These 

data will be coupled with the ongoing biogeochemistry data that we are accumulating for 

the biogeochemistry studies on Chione. 
15

In contrast to Chione cancellata, observations of living Cerithium sp. cf. C. 

eburneum and Turbo castanea have been restricted to marine to polyhaline environments 

in the regions in and around Florida Bay. C. sp. cf. C. eburneum demonstrated a narrow 

range of tolerance to salinity and temperature changes in all experiments, which agrees 

with our in situ observations in Florida Bay. Turbo castanea survived well in the control 

system but did not survive well in any experimental scenarios. 

The nine species in this experiment represent common members of the overall 

assemblage of mollusks in Florida Bay. By the very nature of the experimental process 

however, the tested organisms are biased towards: 1) species that can survive the rigors 

and stress of relocation and equilibration into the mesocosms at LSC; and 2) species that 

are relatively abundant and easy to locate and collect in the field. Given this sampling 

bias, we expected the selected species to be tolerant of a range of salinities and 

temperature within seasonal limits, and the experiments demonstrated that they were. 

The mortality rates began to change, however, when we exceeded the typical seasonal 

range taking the systems to recorded highs and lows of salinity and temperature. With 

few exceptions the broad range (60-0.0 ppt) of temperatures and salinities, which have 

been recorded in situ (Figure 4), caused a large die-off of the original test organisms. The 

experimental results demonstrate that even the most common and resilient members of 

the ecosystem have a point at which survival is very limited. 

The South Florida ecosystem has evolved to withstand changes due to extremes in 

weather, limited nutrient loading and subtle overall changes. However, when seasonal 

changes are coupled with point source stresses, brought about by controlled water 

delivery for example, the resulting pressure may be overwhelming. A better 

understanding of why and how these resilient species cope with changes in salinity and 

temperature is needed as is experimentation on rapidly changing cycles of salinity and 

temperature. These data should provide another indicator by which resource mangers can 

monitor change so that habitat loss can be averted. 

SUMMARY

The primary goal of the Comprehensive Everglades Restoration Project is to 

restore more natural freshwater flow through the south Florida ecosystem including 

quantity and timing of freshwater deliveries into the system, and maintaining water 

quality within the overall system. Understanding the effect of salinity and temperature, 

beyond typical oscillations, on the biota of the South Florida estuaries is necessary for the 

successful outcome of the overall goals of CERP. These experiments addressed two 

aspects of the Ecosystem History Projects: 1) determining the utility of using molluscan 

shells as recorders of change in water chemistry parameters, primarily salinity, and 2) 

enhancing our in situ observations on modern assemblages by exceeding typically 

observed conditions. These experiments allowed us to gain an understanding of the 

effects of salinity, temperature and other water chemistry parameters on the reproduction, 

growth and overall survivability of key species of mollusks, used in interpreting sediment 

core data. 
Starting # Chione cancellata =10

Starting # Modulus modulus =20

0

102030405060708090

100

9/22/03

10/6/03

10/20/03

11/3/03

11/17/03

12/1/03

12/15/03

12/29/03

1/12/04

1/26/04

2/9/04

2/23/04

3/8/04

3/22/04

4/5/04

4/19/04

0

102030405060708090

100

9/22/03

10/6/03

10/20/03

11/3/03

11/17/03

12/1/03

12/15/03

12/29/03

1/12/04

1/26/04

2/9/04

2/23/04

3/8/04

3/22/04

4/5/04

4/19/04

0

102030405060708090

100

9/22/03

10/6/03

10/20/03

11/3/03

11/17/03

12/1/03

12/15/03

12/29/03

1/12/04

1/26/04

2/9/04

2/23/04

3/8/04

3/22/04

4/5/04

4/19/04

0

102030405060708090

100

9/22/03

10/6/03

10/20/03

11/3/03

11/17/03

12/1/03

12/15/03

12/29/03

1/12/04

1/26/04

2/9/04

2/23/04

3/8/04

3/22/04

4/5/04

4/19/04

0

102030405060708090

100

9/22/03

10/6/03

10/20/03

11/3/03

11/17/03

12/1/03

12/15/03

12/29/03

1/12/04

1/26/04

2/9/04

2/23/04

3/8/04

3/22/04

4/5/04

4/19/04

0

102030405060708090

100

9/22/03

10/6/03

10/20/03

11/3/03

11/17/03

12/1/03

12/15/03

12/29/03

1/12/04

1/26/04

2/9/04

2/23/04

3/8/04

3/22/04

4/5/04

4/19/04

0

102030405060708090

100

9/22/03

10/6/03

10/20/03

11/3/03

11/17/03

12/1/03

12/15/03

12/29/03

1/12/04

1/26/04

2/9/04

2/23/04

3/8/04

3/22/04

4/5/04

4/19/04

0

102030405060708090

100

9/22/03

10/6/03

10/20/03

11/3/03

11/17/03

12/1/03

12/15/03

12/29/03

1/12/04

1/26/04

2/9/04

2/23/04

3/8/04

3/22/04

4/5/04

4/19/04

0

102030405060708090

100

9/22/03

10/6/03

10/20/03

11/3/03

11/17/03

12/1/03

12/15/03

12/29/03

1/12/04

1/26/04

2/9/04

2/23/04

3/8/04

3/22/04

4/5/04

4/19/04

10203040506070

9/22/2003

10/6/2003

10/20/2003

11/3/2003

11/17/2003

12/1/2003

12/15/2003

12/29/2003

1/12/2004

1/26/2004

2/9/2004

2/23/2004

3/8/2004

3/23/2004

4/6/2004

5.0010.0015.0020.0025.0030.00

Temperature in degrees C

salinity sys 1btemp sys 1b

Starting # Columbella rusticoides =10

Starting # Cerithium muscarum =20

Starting # Cerithium ebernium =5 

Starting # Turbo castenea =10

Starting # Bulla striata =10

Starting # Prunum apicinum =5

Starting # Brachidontes exustus =20

0

102030405060708090

100

9/22/03

10/6/03

10/20/03

11/3/03

11/17/03

12/1/03

12/15/03

12/29/03

1/12/04

1/26/04

2/9/04

2/23/04

3/8/04

3/22/04

4/5/04

4/19/04

0

102030405060708090

100

9/22/03

10/6/03

10/20/03

11/3/03

11/17/03

12/1/03

12/15/03

12/29/03

1/12/04

1/26/04

2/9/04

2/23/04

3/8/04

3/22/04

4/5/04

4/19/04

0

102030405060708090

100

9/22/03

10/6/03

10/20/03

11/3/03

11/17/03

12/1/03

12/15/03

12/29/03

1/12/04

1/26/04

2/9/04

2/23/04

3/8/04

3/22/04

4/5/04

4/19/04

0

102030405060708090

100

9/22/03

10/6/03

10/20/03

11/3/03

11/17/03

12/1/03

12/15/03

12/29/03

1/12/04

1/26/04

2/9/04

2/23/04

3/8/04

3/22/04

4/5/04

4/19/04

0

102030405060708090

100

9/22/03

10/6/03

10/20/03

11/3/03

11/17/03

12/1/03

12/15/03

12/29/03

1/12/04

1/26/04

2/9/04

2/23/04

3/8/04

3/22/04

4/5/04

4/19/04

0

102030405060708090

100

9/22/03

10/6/03

10/20/03

11/3/03

11/17/03

12/1/03

12/15/03

12/29/03

1/12/04

1/26/04

2/9/04

2/23/04

3/8/04

3/22/04

4/5/04

4/19/04

0

102030405060708090

100

9/22/03

10/6/03

10/20/03

11/3/03

11/17/03

12/1/03

12/15/03

12/29/03

1/12/04

1/26/04

2/9/04

2/23/04

3/8/04

3/22/04

4/5/04

4/19/04

0

102030405060708090

100

9/22/03

10/6/03

10/20/03

11/3/03

11/17/03

12/1/03

12/15/03

12/29/03

1/12/04

1/26/04

2/9/04

2/23/04

3/8/04

3/22/04

4/5/04

4/19/04

0

102030405060708090

100

9/22/03

10/6/03

10/20/03

11/3/03

11/17/03

12/1/03

12/15/03

12/29/03

1/12/04

1/26/04

2/9/04

2/23/04

3/8/04

3/22/04

4/5/04

4/19/04

102030405060

9/22/2003

10/6/2003

10/20/2003

11/3/2003

11/17/2003

12/1/2003

12/15/2003

12/29/2003

1/12/2004

1/26/2004

2/9/2004

2/23/2004

3/8/2004

3/22/2004

4/5/2004

10.0015.0020.0025.0030.0035.0040.00

salinity sys 1a Temperature in degrees Ctemp sys 1a

Starting # Turbo castenea =10

Starting # Bulla striata =10

Starting # Prunum apicinum =5

Starting # Brachidontes exustus =20

Starting # Chione cancellata =10Starting # Modulus modulus =20

Starting # Columbella rusticoides =10

Starting # Cerithium muscarum =20

0

102030405060708090

100

9/22/03

10/6/03

10/20/03

11/3/03

11/17/03

12/1/03

12/15/03

12/29/03

1/12/04

1/26/04

2/9/04

0

102030405060708090

100

9/22/03

10/6/03

10/20/03

11/3/03

11/17/03

12/1/03

12/15/03

12/29/03

1/12/04

1/26/04

2/9/04

0

102030405060708090

100

9/22/03

10/6/03

10/20/03

11/3/03

11/17/03

12/1/03

12/15/03

12/29/03

1/12/04

1/26/04

2/9/04

0

102030405060708090

100

9/22/03

10/6/03

10/20/03

11/3/03

11/17/03

12/1/03

12/15/03

12/29/03

1/12/04

1/26/04

2/9/04

0

102030405060708090

100

9/22/03

10/6/03

10/20/03

11/3/03

11/17/03

12/1/03

12/15/03

12/29/03

1/12/04

1/26/04

2/9/04

0

102030405060708090

100

9/22/03

10/6/03

10/20/03

11/3/03

11/17/03

12/1/03

12/15/03

12/29/03

1/12/04

1/26/04

2/9/04

0

102030405060708090

100

9/22/03

10/6/03

10/20/03

11/3/03

11/17/03

12/1/03

12/15/03

12/29/03

1/12/04

1/26/04

2/9/04

0

102030405060708090

100

9/22/03

10/6/03

10/20/03

11/3/03

11/17/03

12/1/03

12/15/03

12/29/03

1/12/04

1/26/04

2/9/04

0

102030405060708090

100

9/22/03

10/6/03

10/20/03

11/3/03

11/17/03

12/1/03

12/15/03

12/29/03

1/12/04

1/26/04

2/9/04

10.0015.0020.0025.0030.0035.0040.00

9/22/2003

10/6/2003

10/20/2003

11/3/2003

11/17/2003

12/1/2003

12/15/2003

12/29/2003

1/12/2004

1/26/2004

2/9/2004

2/23/2004

Salinity

salinity sys 2btemp sys 2b

S m

Starting # 

Starting 

Starting # 

Starting # Brach

Starting # CStarting # M

Starting # Colum

0

102030405060708090

100

9/22/03

10/6/03

10/20/03

11/3/03

11/17/03

12/1/03

12/15/03

12/29/03

1/12/04

1/26/04

2/9/04

2/23/04

3/8/04

3/22/04

4/5/04

4/19/04

0

102030405060708090

100

9/22/03

10/6/03

10/20/03

11/3/03

11/17/03

12/1/03

12/15/03

12/29/03

1/12/04

1/26/04

2/9/04

2/23/04

3/8/04

3/22/04

4/5/04

4/19/04

0

102030405060708090

100

9/22/03

10/6/03

10/20/03

11/3/03

11/17/03

12/1/03

12/15/03

12/29/03

1/12/04

1/26/04

2/9/04

2/23/04

3/8/04

3/22/04

4/5/04

4/19/04

0

102030405060708090

100

9/22/03

10/6/03

10/20/03

11/3/03

11/17/03

12/1/03

12/15/03

12/29/03

1/12/04

1/26/04

2/9/04

2/23/04

3/8/04

3/22/04

4/5/04

4/19/04

0

102030405060708090

100

9/22/03

10/6/03

10/20/03

11/3/03

11/17/03

12/1/03

12/15/03

12/29/03

1/12/04

1/26/04

2/9/04

2/23/04

3/8/04

3/22/04

4/5/04

4/19/04

0

102030405060708090

100

9/22/03

10/6/03

10/20/03

11/3/03

11/17/03

12/1/03

12/15/03

12/29/03

1/12/04

1/26/04

2/9/04

2/23/04

3/8/04

3/22/04

4/5/04

4/19/04

10152025303540

9/22/2003

10/6/2003

10/20/2003

11/3/2003

11/17/2003

12/1/2003

12/15/2003

12/29/2003

1/12/2004

1/26/2004

2/9/2004

2/24/2004

3/9/2004

3/23/2004

4/6/2004

Salinity

5.0010.0015.0020.0025.0030.0035.0040.00

Temperature in C

0

102030405060708090

100

9/22/2003

10/6/2003

10/20/2003

11/3/2003

11/17/2003

12/1/2003

12/15/2003

12/29/2003

1/12/2004

1/26/2004

2/9/2004

2/23/2004

3/8/2004

3/22/2004

4/5/2004

4/19/2004

0

102030405060708090

100

9/22/2003

10/6/2003

10/20/2003

11/3/2003

11/17/2003

12/1/2003

12/15/2003

12/29/2003

1/12/2004

1/26/2004

2/9/2004

2/23/2004

3/8/2004

3/22/2004

4/5/2004

4/19/2004

Starting # Cerithium muscarum =20

Starting # Cerithium ebernium =5 

Starting # Turbo castenea =10

Starting # Bulla striata =10

Starting # Prunum apicina? =5

Starting # Brachidontes exustus =20

Starting # Chione cancellata =10

Starting # Modulus modulus =20

0

102030405060708090

100

9/22/03

10/6/03

10/20/03

11/3/03

11/17/03

12/1/03

12/15/03

12/29/03

1/12/04

1/26/04

2/9/04

2/23/04

3/8/04

3/22/04

4/5/04

4/19/04

Starting # Columbella rusticoides =10

0

102030405060708090

100

9/22/03

10/6/03

10/20/03

11/3/03

11/17/03

12/1/03

12/15/03

12/29/03

1/12/04

1/26/04

2/9/04

2/23/04

3/8/04

3/22/04

4/5/04

4/19/04

0

102030405060708090

100

9/22/03

10/6/03

10/20/03

11/3/03

11/17/03

12/1/03

12/15/03

12/29/03

1/12/04

1/26/04

2/9/04

2/23/04

3/8/04

3/22/04

4/5/04

4/19/04

0

102030405060708090

100

9/22/03

10/6/03

10/20/03

11/3/03

11/17/03

12/1/03

12/15/03

12/29/03

1/12/04

1/26/04

2/9/04

2/23/04

3/8/04

3/22/04

4/5/04

4/19/04

0

102030405060708090

100

9/22/03

10/6/03

10/20/03

11/3/03

11/17/03

12/1/03

12/15/03

12/29/03

1/12/04

1/26/04

2/9/04

2/23/04

3/8/04

3/22/04

4/5/04

4/19/04

0

102030405060708090

100

9/22/03

10/6/03

10/20/03

11/3/03

11/17/03

12/1/03

12/15/03

12/29/03

1/12/04

1/26/04

2/9/04

2/23/04

3/8/04

3/22/04

4/5/04

4/19/04

0

102030405060708090

100

9/22/03

10/6/03

10/20/03

11/3/03

11/17/03

12/1/03

12/15/03

12/29/03

1/12/04

1/26/04

2/9/04

2/23/04

3/8/04

3/22/04

4/5/04

4/19/04

0

102030405060708090

100

9/22/03

10/6/03

10/20/03

11/3/03

11/17/03

12/1/03

12/15/03

12/29/03

1/12/04

1/26/04

2/9/04

2/23/04

3/8/04

3/22/04

4/5/04

4/19/04

10.0015.0020.0025.0030.0035.0040.00

9/22/2003

10/6/2003

10/20/2003

11/3/2003

11/17/2003

12/1/2003

12/15/2003

12/29/2003

1/12/2004

1/26/2004

2/9/2004

2/23/2004

3/8/2004

3/22/2004

4/5/2004

4/19/2004

Salinity

10152025303540

salinity(ppt) system A Temperature in degrees Ctemp sys A

Starting # Brachidontes exustus =20

Starting # Chione cancellata =10

0

102030405060708090

100

9/22/03

10/6/03

10/20/03

11/3/03

11/17/03

12/1/03

12/15/03

12/29/03

1/12/04

1/26/04

2/9/04

2/23/04

3/8/04

3/22/04

4/5/04

4/19/04

Starting # Modulus modulus =20

0

102030405060708090

100

9/22/03

10/6/03

10/20/03

11/3/03

11/17/03

12/1/03

12/15/03

12/29/03

1/12/04

1/26/04

2/9/04

2/23/04

3/8/04

3/22/04

4/5/04

4/19/04

Starting # Columbella rusticoides =10

Starting # Cerithium muscarum =20

Starting # Cerithium ebernium =5 

Starting # Turbo castenea =10

Starting # Bulla striata =10

Starting # Prunum apicinum =5

Starting # Cerithium ebernium =5 

salinity sys 2atemp sys 2a

Salinity

Salinity
16

Observations on mollusks, plants and microbes made as part of these experiments 

have further refined our knowledge and understanding of the effects of ecosystem 

feedback and what role salinity and temperature play in ecosystem stability. Data 

collected on the effects of salinity and temperature driven changes need to be verified or 

tested in the field. The mesocosms and experiments were designed in part based on 

observations made in South Florida estuaries. Observations made in the mesocosms, on a 

scale not normally observable in the field, have led to new questions about the influence 

of salinity on the localized ecosystem, which need to be tested in situ. 

The results have demonstrated the viability of several molluscan species (for 

example Cerithium muscarum, and Bulla striata due to the ability to withstand a broad 

salinity range) that could be utilized as indicators of atypical salinity, and possibly 

temperature, oscillations. These data and the use of these species can provide a more 

accurate measure of anthropogenic influence in the South Florida estuaries. The 

experiments also have provided calibration data for the shell biogeochemistry of Chione 

cancellata and the use of this species as a water chemistry recorder. The next phase of 

experiments will test the stress levels/survival rates of repeated, short duration changes of 

salinity and temperature at various intensities. We would also like to expand the 

biogeochemistry study of Chione cancellata to include several of the gastropod species 

utilized in this experiment. 

REFERENCES 

Light, S.S., and Dineen, J.W., 1994, Water control in the Everglades: a historical 

perspective, in Davis, S.M., and Ogden, J.C., editors, Everglades: the Ecosystem 

and its restoration: Delray Beach, FL., St. Lucie Press, pp. 47-84. 

McPherson, B.F. and Halley, R., 1996, The south Florida environment – a region under 

stress: US Geological Survey Circular 1134, 61 pp. 

Murray, J.B., Schill, W.B., and Wingard, G.L., 2004, Florida in a Tank, U.S Geological 

Survey Fact Sheet #2004-3116. 

Stamm, R.G., and Wingard, G.L., 2004, Shells as Recorders of Environmental Change—

A Study in Florida Bay, U.S Geological Survey Fact Sheet# 2004-3141. 
Species List 

Plants: 

Algae 

Chlorophyta 

Avrainvillea nigricans 

Batophora occidentalis var. largoensis 

Batophora oerstedii 

Caulerpa paspaloides 

Caulerpa prolifera 

Caulerpa cupressoides 

Caulerpa sertularoides 

Caulerpa serulata var. hummii 

Caulerpa ashmeadii 

Caulerpa mexicana 

Caulerpa racemosa var. occidentalis 

Caulerpa racemosa var. peltata 

Caulerpa taxifolia 

Chaetomorpha crassa 

Chaetomorpha linum 

Cladophora liniformis 

Cladophora prolifera 

Dictyosphera cavernosa 

Dasycladus vermicularis 

Neomeris annulata 

Enteromorpha compressa 

Enteromorpha flexuosa 

Batophora oerstedi 

Penicillis capitatus 

Penicillis dumetosus 

Phipocephalus phoenix 

Acetabularia crenulata 

Acetabularia schenkii 

Anadyomene stellata 

Halimeda monile 

Halimeda opuntia 

Halimeda incrassata 

Halimeda discoidea 

Halimeda tuna 
Udotea flabellum 

Udotea cyathiformis 

Valonia ventricosa 

Valonia cavernosa 

Valonia aegagropila 

Valonia macrophysa 

Valonia utriularis 

 Rhodophyta 

Polysiphonia subtillisima 

Spyridia filimentosa 

Laurencia sp. 

Digenia simplex 

Hydrolithion farinosum 

Pneophyllum fragile 

Titanoderma pustulatum 

Hypnea musciformis 

Gracilariopsis lamaneiformis 

Lomentaria baileyana 

Ceramium brevizonatum var. caraibicum 

Tiffaiella gorgonea 

Dasya harveyi 

Dasya ocellata 

Dasya ramosissima 

Heterosiphonia crispella var. laxa 

Chondria atropurpurea 

Polysiphonia havanensis 

Polysiphonia opaca 

Wrightiella tumanowiczii 

 Phaeophyta 

Order Dictyotales 

Family Dictyotaceae 

Dictyota cervicornis 

Dictyota dichotoma 

Dictyota crispate 

Dictyota crenulata 

Dictyota mertensii 

Order Ectocarpales 

Family Ectocarpaceae 

Feldmannia indica 
Order Scytosiphonales 

Family Scytosiphonaceae 

Rosenvingia intricate 

Order Fucales 

Family Sargassaceae 

Sagassum filpendula 

Sargassum natans 

Sargassum fluitans 

 Angiosperms 

Thalassia testudinum 

Halodule wrightii 

Syringodium filiforme 

Rhizophora mangle 

Ruppia maritima 

 
Mollusks 

Prunum apicinum 

Cerithium musacarum 

Cerithium eburneum 

Cerithium sp. 

Modulus modulus 

Modulus sp. 

Astraea americana 

Astraea phoebium 

Tricolia affinis 

Nerita sp. 

Rissoina sp. 

Caecum pulchellum 

Caecum sp. 

Vermicularia sp (3) 

Batillaria sp. 

Crepidula sp (2) 

Strombus gallus 

Mitrella sp. 

Mitrella sp. 

Bulla striata. 

Conus sp. 

Tegula sp. 

Corphella verrucosa (nudibranch) 

Order: SACOGLOSSA 

Superfamily: OXYNOOIDEA 

Family: Oxynoidae 

Oxynoe viridis 

Carditamera floridana 

Columbella rusticoides 

Columbella sp. 

Lucina sp. 

Argopectin sp. 

Tellina sp. (2+) 

Chione cancellata 

Brachidontes exustus 

Diodora sp. 

Diodora sp. 

Laevicardium sp. 

Pinna sp. 
Atrina sp. 

Noetia sp.Barbatia sp. 

Arca zebra 

Arca sp. 

Chiton tuberculatus 

Pteria imbricate 

Pteria colymbus 

Turbo castanea 

Echinodermata 

Sea urchins (3) sp. 

Sand dollars 

Holothurians 

Sea cucumbers 3+sp. 

Ophiuroidea 

Brittle stars 6+ sp. 

Asteroidea 

Sea stars (3) sp. 

Bryzoans 

Cnidarians 

14 species of hard and soft corals 

Condactylus gigantea 

Aptasia sp. 

As yet unidentified anemone 

 Crustacea 

Pagurus acadianus

Common Name: Acadian Hermit Crab 

Team: Crustaceans 

Phylum: Arthropoda

Gammarus spp

Common Name: Sand Flea 

Team: Crustaceans 

Phylum: Arthropoda

Mithrax sculptis 

Lobsters 
Peppermint shrimp 

Arrow crabs 

Cyanobacteria 

Hydrocoleum coccineum 

Dichothrix penicillata 
17