This study examined the population density and depth distribution of the long-spined sea urchin Diadema antillarum in Discovery Bay, Jamaica. D. antillarum is a keystone species that regulates algal growth on coral reefs through grazing. The study found that D. antillarum densities were highest between 5-15 meters deep, defining the "Diadema zone." Compared to 2010, D. antillarum populations have increased in 2014 and the depth range of highest densities has become slightly shallower. The recovery of D. antillarum is important for the health of Caribbean coral reefs by limiting competition between algae and corals for space and light.
1. KorallionKorallion
Ecology of Coral ReefsEcology of Coral Reefs
Discovery Bay, JamaicaDiscovery Bay, Jamaica
Volume V, Maymester 2014Volume V, Maymester 2014
2. Suggested citations for Korallion
Volume
Sporre MA, Raynor CB, Kammerer AJ, and EJ Burge, editors. 2014. Korallion. Coastal Carolina Studies in
Coral Reef Ecology. 5: 72 pp.
Individual paper (example)
Baldwin, A. 2014. Population density and depth zonation of the long-spined sea urchin, Diadema antillarum, in
Discovery Bay, Jamaica. Korallion. Coastal Carolina University Studies in Coral Reef Ecology. Sporre
MA, Raynor CB, Kammerer AJ, and EJ Burge, eds. 5:1–4
3. FOREWORD
C
OASTAL CAROLINA UNIVERSITY is a comprehensive, public university with one of the largest undergraduate ma-
rine science programs on the east coast. In 2014 the university added a doctoral program in Marine Science—
Coastal Marine Systems Science to the educational offerings at Coastal. Located in Conway, South Carolina, just
minutes from Myrtle Beach, we are renowned for offering hands-on opportunities to students directly in the
field. Our faculty are research-active in the laboratory and in the field and offer numerous opportunities to involve students
in this research. The Department of Marine Science also offers three study abroad courses that give selected students the
experience of conducting research while abroad.
For almost 30 years, students and faculty from Coastal Carolina have traveled to the University of the West Indies
Discovery Bay Marine Lab (DBML), in Discovery Bay, Jamaica. Here students learn about and gain first hand experience
with coral reef ecosystems. Students participate in a three credit course, MSCI 477: Ecology of Coral Reefs, where they
learn about reef structure, productivity, and diversity, while getting to directly observe what they learn through diving on
the reef. The students also prepare and conduct an independent, faculty-supervised, research project that fulfills three cred-
its of MSCI 499: Directed Undergraduate Research.
The students prepare for the trip, which occurs annually in May, by spending time during the spring semester re-
searching and preparing their projects. Once at DBML, students take part in diving, researching, learning, and enjoying the
tropical coral reefs. They meet the natives, learn the culture, and get a real taste of Jamaica. As the trip ends, the last dives
are logged and presentations and projects are finished. For most participants their Jamaican experience ends here, but com-
pilation of this volume of papers occurs in the fall semester following our trip to Jamaica. Two to three of the students vol-
unteer and are chosen to be editors, enrolling in MSCI 399: Scientific Publishing, during the fall semester to create this
volume.
The following papers are a compilation of the exceptional student research projects that collectively make up the
fifth volume of Korallion. As the editors, we found this process to be sometimes frustrating but extremely rewarding and
fun. We are proud of each paper, and with the authors we worked very hard to create a work that will be beneficial to those
who follow in our footsteps. Working on this volume reminded us of the great experiences and the cherished memories we
have from our time in Discovery Bay. We hope that this collection will contribute to the scientific community and be help-
ful to the students who are selected for the trips in years to come.
i
4. STUDENT EDITORS
Caitlin B. Raynor
Class of 2015
Caitlin is from Laurel, Maryland and graduating with a
B.S. in Marine Science. After graduation she plans to
pursue a Masters of Teaching in middle level science.
She hopes to become an aquarist with the goal of edu-
cating the public about the marine world. Her favorite
memory from Jamaica is a dive she had at Dancing Lady
with Tiffany, Megan, and Ashton, when they spent the
entire dive laughing through their regulators trying to
spear lionfish.
Andrew J. Kammerer
Class of 2014
AJ is from southern New Jersey, and is graduating with
a B.S. in Marine Science. He is attending graduate
school at Coastal Carolina University starting in 2015,
pursuing a masters degree focusing in radar related
ocean wave measurements. All of his favorite memories
from Jamaica involved climbing up things and jumping
off of them, as well as being in the water, diving every
day, as much as possible.
Megan A. Sporre
Class of 2015
Megan is from Bel Air, Maryland and graduating with
honors and dual B.S. degrees in Marine Science and Bi-
ology. After graduation she plans to attend graduate
school in the Pacific Northwest focusing on the popula-
tion genetics of pinnipeds. Her favorite memory from
Jamaica was the last dive at Runaway Bay. The under-
water canyon was breathtaking.
STUDIES IN CORAL REEF ECOLOGYii
5. FACULTY AND STAFF
Erin J. Burge
Associate Professor, Marine Science
eburge@coastal.edu
Dr. Erin Burge has been involved with the Jamaica coral reef ecolo-
gy program since 2007. He has been a certified SCUBA diver since
1988 and completed over 240 scientific dives in and around Discov-
ery Bay. His research interests include environmental immunology,
molecular physiology, and molecular biology of marine inverte-
brates and fishes. At Coastal Carolina University, Dr. Burge has
participated in projects ranging from using underwater videos to
monitor grouper populations, molecular tools to detect parasites,
and evaluating ecological changes on Caribbean coral reefs. For
more information visit his faculty web page (www.coastal.edu/
marine/erinburge/ and www.ecologyofcoralreefs.com
Steve Luff
Dive Safety Officer and Instructor
sluff@coastal.edu
Steve Luff has been diving since 1977 and became a SCUBA in-
structor in 1993. Steve is an alumnus of the Ecology of Coral Reefs
program (‘96) and a graduate of the Marine Science program at
Coastal Carolina University. He serves as the scientific dive safety
officer and SCUBA program instructor for CCU. His attention to
safe diving practices and almost 20 years of experience diving the
north-central coast of Jamaica have given him a unique knowledge
of the local diving conditions, environments, and marine life that
are valuable assets to the students conducting field research and
data collection during MSCI 477: Ecology of Coral Reefs
KORALLION. VOL 5. 2014
Dwayne “Skeggy”
Edwards
Coxswain
Naval Feurtado
Driver
Daniel Scarlett
DBML Dive Safety
Officer
Oneil “Snow” Holder
DBML Diver
iii
6. STUDENT PARTICIPANTS
Tiffany M. Beheler
Class of 2014
Tiffany is from Roanoke, Virginia and
graduated with a degree in Marine Sci-
ence with a minor in Biology. Tiffany
hopes to pursue a Masters in Australia
focusing on coral reef ecology. Her fa-
vorite memory from Jamaica was her last
dive with AJ, Cait, and Meg. They got to
dive with a green sea turtle at Runaway
Bay Canyon.
Catharine C. Gordon
Class of 2016
Catharine is from Iowa City, Iowa,
majoring in marine science with a
minor in biology. Her career goals
include becoming a head aquarist
and dive master. Her favorite memo-
ries from the trip are Dunn’s River
Falls and the bonfire with the lab
staff. These were times when the
group bonded and they got to see the
culture of Jamaica.
Megan E. Miller
Class of 2015
Megan is from Pittsburgh, Pennsyl-
vania and pursuing a degree in Ma-
rine Science with a minor in Biolo-
gy. After graduation she plans to
apply for the Peace Corps or to be a
fisheries observer in Alaska. Her
favorite memory from Jamaica is
diving. She loved waking up every
morning and going to dive, it was
beautiful and calming.
Lanie M. Esch
Class of 2015
Melanie is from Grand Rap-
ids, Michigan and came to
Coastal Carolina to study ma-
rine biology. She will gradu-
ate with a B.S. in Marine Sci-
ence and a minor in biology.
She plans to apply for gradu-
ate school in the spring of
2016. Her favorite memory of
Jamaica was the first dive at
Dairy Bull. The beauty of the
reef reminded her of why she
loves what she studies and
plans to do with her future.
Sam M. Cook
Class of 2015
Sam is from Crescent Township, Pennsylva-
nia. She will be graduating with a B.S. in Ma-
rine Science and a double minor in Biology
and Environmental Science. She plans to
attend graduate school for environmental
management or policy and pursue a career
related to that field. Her favorite memory was
getting to see a nurse shark on the forereef.
STUDIES IN CORAL REEF ECOLOGYiv
7. STUDENT PARTICIPANTS
Ariana A. Baldwin
Class of 2015
Ariana is a Marine Science
major and is originally from
Crofton, Maryland. After
graduating, Ariana hopes to
attend graduate school to
continue her career in scien-
tific diving. Her favorite
memory from the Jamaica
was being able to dive mul-
tiple times every day and
visiting Bioluminescent
Bay.
Ashton J. Galarno
Class of 2015
Ashton is from Columbus, Indiana and
majoring in marine science with minors
in biology and Spanish. She plans to
start graduate school the following year,
pursuing a masters degree and/or PhD in
marine biology, focusing on coral reef
ecology. One of her favorite memories
from Jamaica was lionfish 'hunting' with
Tiffany, Megan, and Caitlin.
Brandon Hinze
Class of 2015
Brandon is a Psychology major
with a minor in Marine Science
from Potosi, Missouri. After gradu-
ation in May, he plans to become a
marine animal behaviorist. Some of
his favorite memories were of the
people on the trip along with the
staff at DBML. He also enjoyed the
combination of waking up each
morning to the ocean in a com-
pletely stress-free environment
surrounded by amazing people.
D. Cristina O’Shea
Class of 2014
Cristina was born in Manizales, Co-
lombia and graduated from CCU with
a B.S. in Marine Science and a minor
in Biology. She hopes to attend Texas
A&M University to pursue a Masters
degree in Marine Biology specializing
in the physiological and behavioral
mechanisms that allow marine mam-
mals to dive to great depths for pro-
longed periods of time. She loved the
disposition of the Jamaican people and
their hospitality.
vKORALLION. VOL 5. 2014
8. TABLE OF CONTENTS
POPULATION DENSITY AND DEPTH ZONATION OF THE
LONG-SPINED SEA URCHIN, DIADEMA ANTILLARUM, IN
DISCOVERY BAY, JAMAICA
Ariana A. Baldwin……………………….…………….…1
REEF COVERAGE AND SPECIES RICHNESS WITH RESPECT
TO WATER DEPTH AT DISCOVERY BAY, JAMAICA
Melanie M. Esch……………………….…………………5
OBSERVING THE EFFECTIVENESS OF THE DISCOVERY
BAY FISH SANCTUARY USING REEF SURVEY TECH-
NIQUES
Samantha M. Cook.……………………….………………9
DENSITY, RESIDENCE TIME, AND INDIVIDUAL ASSOCIA-
TION OF FLAMINGO TONGUE SNAILS (CYPHOMA GIBBO-
SUM) ON GORGONIAN HOSTS
Catharine C. Gordon…..……………………..…….……15
STUDIES IN CORAL REEF ECOLOGYvi
9. TUBE AND VASE SPONGE DIVERSITY, ABUNDANCE, AND
DENSITY OF THEIR SYMBIONT, OPHIOTHRIX SUENSONII
Tiffany M. Beheler…………………………………….…19
TABLE OF CONTENTS
DEPTH DISTRIBUTION, SIZE FREQUENCY, AND TIP COLOR
POLYMORPHISM OF THE GIANT SEA ANEMONE, CONDY-
LACTIS GIGANTEA, OF DISCOVERY BAY, JAMAICA
Ashton J. Galarno……………………………..…….……27
A COMPARISON OF THE RIO BUENO AND DISCOVERY
BAYS BASED ON FECAL COLIFORM CONCENTRATION IN
RELATION TO FLUVIAL INPUT AND SURROUNDING HUMAN
DEVELOPMENT
Megan E. Miller…..………………………..……….……35
WATER COLUMN PROFILE AND PHYSICAL/BIOLOGICAL
ANALYSIS OF CRATER LAKE, DISCOVERY BAY, JAMAICA
Andrew J. Kammerer..…………………….…..…………39
KORALLION. VOL 5. 2014 vii
10. TABLE OF CONTENTS
NET MOVEMENT RATES OF ACANTHOPLEURA GRANULATA
WHEN SHELTER AND FOOD ARE PRESENT WITHIN THE
HABITAT
Caitlin B. Raynor…..……………………………….……43
DISTRIBUTION, LENGTH-WEIGHT RELATIONSHIP, BUR-
ROWING RATES, SIZE FREQUENCY, AND COLORATION
FREQUENCY OF DONAX DENTICULATUS IN DISCOVERY
BAY, JAMAICA
Megan A. Sporre…..………………………….……….…47
SHELL EXCHANGE MODELS IN CARIBBEAN HERMIT
CRABS, COENOBITA CLYPEATUS: NEGOTIATOR OR AG-
GRESSOR
D. Cristina O’Shea…..…………………………….……55
STUDIES IN CORAL REEF ECOLOGYviii
11. This research was conducted as part of Coastal Carolina Universi-
ty’s classes MSCI 477, Ecology of Coral Reefs, and MSCI 499,
Directed Undergraduate Research in Discovery Bay, Jamaica, 14
–31 May 2014. Contact e-mail: aabaldwin@coastal.edu
POPULATION DENSITY AND DEPTH ZONATION OF THE LONG-SPINED SEA
URCHIN, DIADEMA ANTILLARUM, IN DISCOVERY BAY, JAMAICA
Ariana A. Baldwin
Department of Marine Science, Coastal Carolina University, PO Box 261954, Conway, SC 29526
ABSTRACT:
Many corals require photosynthesis from symbiotic zooxanthellae that are embedded in their internal tissues. Without
primary production from these symbionts, many corals are unable to surpass maintenance metabolism requirements, thus
substantial reef accretion depends on the presence of zooxanthellae and the availability of light. Benthic shallow water
grazers such as the long-spined sea urchin, Diadema antillarum, effectively limit the growth of macroalgae that outcompete
corals for space, light, and nutrients. Diadema antillarum is considered a keystone species in Caribbean reefs as this urchin
regulates algal growth in shallow reef ecosystems. Diadema antillarum populations throughout the Caribbean have been
slowly recovering from massive die-off events in the early 1980s and 1990s. In the absence of grazing, many Caribbean
reefs have transitioned from a state of coral dominance to a state of macroalgal dominance. This study shows the density of
D. antillarum with depth and quantifies the “Diadema zone” on the western forereef of Discovery Bay, Jamaica. The data
obtained in this study shows that Diadema populations on the forereef have increased from 2010–2014 , and the depth
range where they are most abundant has become slightly shallower.
KEYWORDS: Diadema zone, keystone species, algal growth regulation, population recovery
INTRODUCTION
CORAL REEFS are delicate ecosystems heavily influ-
enced by factors such as light availability, surface
temperature, water quality, and essential symbiotic relation-
ships. Symbiotic zooxanthellae derive energy from light to
provide tropical corals with energy, thus substantial reef
growth depends on the abundance of light (Anthony and
Fabricus 2000). In most reefs, macroalgae dominate zoo-
xanthellae in biomass, resulting in limited zooxanthellae
photosynthesis (Small and Adey 2001). Extensive compe-
tition with algae may cause the coral to expel zooxanthellae
from its internal tissues, known as bleaching (Fitt et al
2001). Benthic shallow-water grazers such as Diadema
antillarum (Philippi, 1845) regulate percent algal cover by
feeding on competitive algae. Without this regulation, al-
gal growth rates greatly exceed those of the corals, result-
ing in competition and possible coral bleaching or mortali-
ty. Multiple experiments by Sammarco (1980) demonstrate
that algal cover and the presence of D. antillarum are in-
versely related. In the absence of D. antillarum, corals suf-
fered severe competitive losses to other benthic organisms
and coralline algae. Because D. antillarum effectively mod-
erates competition and algal cover, this urchin has been
characterized as a keystone species in shallow reef ecosys-
tems. Diadema antillarum has a substantial impact on the
structure of these ecosystems and there may be grave con-
sequences if the abundance of D. antillarum changes sig-
nificantly. The management and understanding of the ef-
fects of sea urchin populations on shallow reef ecosystems
may help to prevent further declination of corals, and may
be a key in avoiding catastrophic ecosystem changes (Alves
et al. 2003).
Over the past few decades, a predominant issue in Car-
ibbean reef ecology is the transition of coral dominance to
macroalgal dominance. Discovery Bay has been a study
site since the 1950s and is at the forefront of reports show-
ing a trend in the shift of reefs to macroalgal dominance.
Throughout the 1950s, Jamaican reefs were characterized
by few macroalgae with scleractinian coverage on about
90% of substrates (Edmunds and Carpenter 2001). In 1983,
a disease event devastated the predominant Caribbean ur-
chin, D. antillarum (Mumby et al. 2006). Two major hurri-
canes occurring in the 1990s in combination with the dis-
ease event caused a substantial loss of local Diadema. Sub-
sequently, coral cover has been recorded to less than 10%
and macroalgae reaches depths up to 35 meters (Edmunds
and Carpenter 2001). Although numbers of D. antillarum
have been slowly increasing over the last two decades, Car-
ibbean reefs have continued to deteriorate (Mumby et al.
2006). This decline in Caribbean reef systems can be at-
tributed to both natural and anthropogenic factors; global
pollution, sea temperature rise, dominance of algae, and
centuries of overfishing are some of the causes for reef
degradation in combination with smaller-scale local sources
(Mumby et al. 2006).
The fringing reef system of Discovery Bay is located on
the northern coast of the Caribbean island, Jamaica. The
KORALLION. VOL 5. 2014 1
12. reef sits above a narrow shelf, sheltering the lagoon from
oceanic swells. The bay lies in close proximity to a popu-
lated, industrial town. Anthropogenic factors such as over-
fishing, tourism, pollution, and runoff as well as sedimenta-
tion and disease associated with bauxite shipping vessels
have caused large amounts of reef degradation in this area.
Overfishing has led to the decline of local herbivorous fish
populations, and the rise of noncrustose algae (Mumby et
al. 2006). This harmful algal bloom persists in shallow
coastal Jamaican waters as local D. antillarum populations
have had only a small recovery.
However, local populations in small patches in Caribbe-
an reefs have seen a rise nearing populations recorded in
the late 1970s and early 1980s. From 1992–1996 there was
a significant increase in D. antillarum with abundant local
population sizes in shallow coastal water. Three similar
studies from 2010–2012 recorded the average density of D.
antillarum in shallow reef areas in Discovery Bay, Jamaica.
The results of these studies show the gradual increase in D.
antillarum populations over a recent 3-year span. Keller
(2010) found an average of 2.77 urchins per square meter,
Touse (2011) found an average of 3.23 urchins per square
meter, and Feldman (2012) found an average of 4.78 ur-
chins per square meter. Although the increase in D. antil-
larum since the die-off events has been slow, if these trends
continue, and populations of this herbivorous echinoid con-
tinue to expand spatially, macroalgae cover will decrease,
giving rise to a dominance of coral cover once again
(Edmunds and Carpenter 2001).
METHODS
The methods used in the study were adapted from stud-
ies done by Sellers (2009), Keller (2010), Touse (2011),
and Feldman (2012). Diadema antillarum was sampled by
SCUBA diving sessions using a transect and count method.
Nineteen 30 m transect belts were placed between 2.0–14.0
m deep. Depth readings were recorded using dive gauges,
and substrate type was also noted.
Transects were placed both parallel and perpendicular
to the western forereef region in three permanent mooring
stations on the outskirts of the opening of Discovery Bay,
including M1, Dancing Lady, and LTS (Long-term site).
Eight transects were placed parallel to the forereef, facing
southeast. The parallel transects were placed in shallow
areas where D. antillarum appeared to be most abundant,
these transects were sectioned off every 6 m and D. antil-
larum within 2 m of the transect were identified, counted
and recorded. Perpendicular transects were placed at vari-
ous depths facing North to South and sectioned off every 3
m, urchins were counted within 1 m of the transect.
Depths were determined for blocks along the transect
using dive gauges. The data obtained in the study was then
used to calculate the density of D. antillarum at each depth
block. Density values were calculated by dividing the num-
ber of urchins found by the standardized sample area and
then these numbers were averaged to give the average den-
sity at each depth block. The average densities with depth
were then compared to the averages obtained from 2010–
2012 and graphed to show the growth or retraction of the
local population size. Finally, an ANOVA test was run in
order to demonstrate a significant difference between the
numbers of urchins counted inside and outside of the deter-
mined zone.
RESULTS
This study assessed the population density and distribu-
tion with depth of D. antillarum in Discovery Bay, Jamai-
ca; an area that has been extensively studied for over fifty
years. Analysis of the data collected in this study showed
that the average density across all transects was 4.15 ur-
chins m-2
(STDEV=3.15), which is lower than the average
densities observed in previous years. However, in this
study, more transects were placed in deeper locations to
demonstrate a strong correlation with depth. An average
taken between all transects placed in closer proximity to the
“Diadema zone” gave a density of 5.59 (STDEV= 2.65),
compared to an average density of 4.78 observed by Feld-
man in 2012 (Standard deviation unknown). The average
densities per year observed from 2010-2014 have consist-
ently increased with each consecutive year (Figure 1).
Figure 1. The average D. antillarum density in the Diadema zone
per year from 2010–2014 is shown in the graph above. There was
an average of 2.77 urchins per square meter observed in 2010 with
a standard deviation of 2.02, 3.23 urchins m-2
with a standard de-
viation of 2.63 in 2011, 4.78 urchins m-2
(standard deviation un-
known) in 2012, and an average of 5.59 urchins m-2
with a stand-
ard deviation of 2.65 in 2014.
BALDWIN: DIADEMA ZONATION
The highest density recorded was 9.47 urchins m-2
at
approximately 1.5 m, compared to a maximum of 7 urchins
recorded per square meter in previous years. The lowest
density recorded per square meter was 0 urchins at all
depths observed below 7 m. Using the average densities
calculated for each depth category, the “Diadema zone”
2
13. spans from about 1.5 m –5.3 m (Figure 2). Standard devia-
tions in this survey tend to be relatively high because D.
antillarum cluster together in small patches and densities
are highly variable at any given location. Transects were
also placed in areas with varying substrate types, thus in
locations within the same depth range, different numbers of
urchins were found based on the bottom composition. Den-
sities inside and outside of this range of depths were signif-
icantly different, with a p-value of 0.0. A linear regression
was run to test the correlation between depth and density of
D. antillarum. There was a strong negative correlation with
density as depth increased based on the regression analysis
(Figure 3).
DISCUSSION
Diadema antillarum populations throughout the Carib-
bean have been slowly recovering after the die-off events
that occurred in the early 1980s and 1990s. The data ob-
tained in this study and similar studies in Discovery Bay
demonstrate that local D. antillarum populations have been
increasing over the past four years. Since 2010, the average
density has increased from 2.77 m-2
(Keller 2010) to 5.59 m
-2
in 2014. Diadema antillarum has few natural predators in
Jamaican reefs, although local fishermen often use them as
bait in fish pots. Without large storm events and the ab-
sence of species-wide diseases, the D. antillarum popula-
tion in Discovery Bay should continue to grow as space and
food remain available. However, due to the fact that D.
antillarum occupy such a narrow depth range and tend to
be arranged in a clustered formation, intraspecific competi-
tion might curb exponential growth rates.
Diadema antillarum have made such a substantial
recovery over the past few years that the “Diadema zone”
has been grazed to the point of bare substrate exposure in
most areas. It was also noted in this study that feeding scars
from the rigid mouth of D. antillarum were apparent on
some coral species such as Porites astreoides (Lamarck,
1816), as urchins have begun to graze on certain corals
because preferred algae have become less abundant in shal-
low waters. About 8.2% of the D. antillarum populations in
the Netherlands Antilles have been observed feeding on
coral surfaces (Bak and van Eys 1975). The zonation with
depth observed in this study was determined to be from
about 1.5 m–5.3 m, this range of depths is slightly shallow-
er than the depth range observed by Feldman (2012) which
found that the “Diadema zone” had previously been 2.5–
6.5m. In other studies, it has been concluded that D. antil-
larum have been recovering and abundant in shallow wa-
ters throughout the entire Caribbean (<6 m) (Carpenter
2006). Diadema antillarum continue to be most abundant
in this depth range because of the types of algae that are
prevalent in these areas as well as the types of substrates
that tend to occupy mid to shallow depths.
Further studies should be done in order to determine
the algal feeding preferences of D. antillarum versus other
urchin species and if that is significant in the depth zona-
tion of D. antillarum. Substrate type and complexity are
also factors that determine the areas in which D. antillarum
can be found. Out of 3,372 urchins counted during this
study, less than 5 were observed on bare sand (assumed to
be in transit), while some were found on flat, bare rock
substrates, and the remaining majority were found in cracks
and crevices or on rubble substrate. In a similar study in-
cluding rugosity measurements, it was found that there was
a strong correlation between substrate complexity, and ur-
chin density (Feldman 2012). Although it is apparent from
observation alone, further studies should continue to in-
clude substrate preferences to determine a statistically sig-
nificant effect on density.
Figure 2. The average density values for D. antillarum standard-
ized to a m-2
against depth. This graph shows that D. antillarum is
abundant in shallow depths and there are few to none below 6m.
The dashed lines represent the “Diadema zone” which ranges
from approximately 1.5–5.3 m.
Figure 3. Figure 3 shows the results of a linear regression analy-
sis with density (m-2
) as the dependent variable and depth as the
independent variable. This figure demonstrates the relationship
between urchin density and depth. The regression line shows that
there is a strong negative correlation between density and depth,
with an R2
value of 0.76 and an equation of y = -0.90x + 8.73.
KORALLION. VOL 5. 2014 3
14. The “Diadema zone” quantified in this study helps to
determine the present condition of D. antillarum popula-
tions. The “Diadema zone” typically contains smaller
amounts of algal coverage, and is suggestive of a reversal
in community structure. This data shows that the zonation
of D. antillarum has remained relatively the same in the
forereef from 2012–2014, but has become shallower. The
density of D. antillarum inside the “Diadema zone” is sig-
nificantly different than densities outside of this depth
zone. This demonstrates that the depths at which D. antil-
larum can be found are narrow and strict. Many similar
studies have shown that D. antillarum continue to occupy a
narrow depth range, however, based upon this study, that
depth range has changed from 2.5–6.5 m to 1.5–5.3 m. Fur-
ther studies will show whether or not this shallow zonation
will continue with time as the population continues to
grow.
There are many different factors that govern healthy
coral reef ecosystems, many of which are human-related.
Estimation of carrying capacities for reef fishes and urchins
should be established in order to prevent overfishing of
herbivorous grazers such as reef fishes and urchins. A re-
cent reversal in the D. antillarum density and surrounding
grazed areas show signs of Caribbean reef improvement as
urchin populations continue to expand. The presence and
abundance of D. antillarum is directly related to the percent
coral cover (Sammarco 1980). This relationship is due to
the limitation of competitive algae by D. antillarum. Herbi-
vore regulation by grazing is the major factor controlling
algal growth on reefs (Albert et al. 2008). Understanding
and maintaining urchin and fish populations will ensure
that corals will once again dominate Caribbean reefs.
ACKNOWLEDGMENTS
I would like to express my appreciation for the finan-
cial support of my family, and for the guidance and assis-
tance provided by E Burge. I also thank the staff of Discov-
ery Bay Marine Lab for allowing the use of their facilities
and equipment, and for providing constant aid. D Scarlett,
C Trench, O Holder, and D Edwards assisted with all div-
ing sessions, enabling the collection of data. Finally, I
thank my dive buddy M Esch who facilitated the dive por-
tion of this research.
LITERATURE CITED
Albert S, Udy J, Tibbetts IR. 2008. Responses of algal communi-
ties to gradients in herbivore biomass and water quality in
Marovo Lagoon, Solomon Islands. Coral Reefs. 27:73-82.
Alves FM, Chicharo LM, Serrao E, Abreu AD. 2003. Grazing by
Diadema antillarum (Philippe) upon communities on rocky
substrates. Scientia Marina. 67(3): 307-311.
Anthony KN, Fabricus KE. 2000. Shifting roles of heterotrophy
and autotrophy in coral energetics under varying turbidity. J
Exp Mar Bio Ecol. 252(2000): 221-253.
Bak RP, van Eys G. 1975. Predation of the sea urchin Diadema
antillarum Philippi on living coral. Oecologia. 20:111-115.
Carpenter RC, Edmunds PJ. 2006. Local and regional scale recov-
ery of Diadema promotes recruitment of scleractinian cor-
als. Ecol Letters. 9: 271-280.
Edmunds PJ, Carpenter RC. 2001. Recovery of Diadema antil-
larum reduces macroalgal cover and increases abundance of
juvenile corals on a Caribbean reef. Proc Natl Acad Sci
USA. 89(9): 5067-5071.
Feldman BA. 2012. The effects of depth rugosity on the distribu-
tion and density of Diadema antillarum at Discovery Bay,
Jamaica. Korallion. 3: 14-17.
Fitt WK, Brown BE, Warner ME, Dunne RP. 2001. Coral bleach-
ing: Interpretation of thermal tolerance limits and thermal
thresholds in tropical corals. Coral Reefs. 20: 51-65.
Keller J. 2010. Density and distribution of the long-spined sea
urchin, Diadema antillarum, with respect to rugosity at
Discovery Bay, Jamaica. Korallion. 1:31-36.
Mumby PJ, Hedley JD, Zychaluk K, Harborne AR, Blackwell
PG. 2006. Revisiting the catastrophic die-off of the urchin
Diadema antillarum of Caribbean coral reefs: Fresh insights
on resilience from a simulation model. Ecol Model. 196(1-
2): 131-148.
Sammarco PW. 1980. Diadema and its relationship to coral spat
mortality: Grazing, competition, and biological disturbance.
J Exp Mar Biol Ecol. 45: 245-272.
Sellers AJ, Casey LO, Burge EJ, Koepfler ET. 2009. Population
Growth and distribution of Diadema antillarum at Discov-
ery Bay, Jamaica. Open J Mar Bio. 3: 105-111.
Small AM, Adey WH. 2001. Reef corals, zooxanthellae and free-
living algae: A microcosm study that demonstrates synergy
between calcification and primary production. Ecol Eng. 16:
443-457.
Touse R. 2011. Density and distribution changes of Diadema
antillarum relating to depth and rugosity at Discovery Bay,
Jamaica. Korallion. 1: 14-19.
BALDWIN: DIADEMA ZONATION4
15. REEF COVERAGE AND SPECIES RICHNESS WITH RESPECT TO WATER
DEPTH AT DISCOVERY BAY, JAMAICA
Melanie M. Esch
Department of Marine Science, Coastal Carolina University, PO Box 261954, Conway, SC 29526
ABSTRACT
Recently, the community structure of the fore reef at Discovery Bay, Jamaica has been macroalgal dominated. Factors
important in controlling coral distribution in Jamaica include: hurricanes, coral bleaching, herbivorous fish, urchins, and
light. With less events in recent years that would inhibit the growth and expansion of corals, the reef may be transitioning
from its algal state. Living coral cover at 3 m–12 m depth has increased by 5% since 2006 and is now approximately 20%.
At Dairy Bull (a study site east of Discovery Bay), the corals dominated the reef at an average of 43% coverage at 9 m–12
m depth. The species richness increases during the transition from shallow to mid-waters and then is consistent to a depth
of 12 m. The coral coverage at the fore reef in Discovery Bay, Jamaica, is increasing, and may undergo a shift in domi-
nance within the next decade as a result of increasing amounts of grazing fish from the input of a fish sanctuary, the return
of Diadema antillarum, and the controlling of coral bleaching.
KEYWORDS: Percent coverage, coral community, macroalgae, depth zonation
This research was conducted as part of Coastal Carolina Universi-
ty’s classes MSCI 477, Ecology of Coral Reefs, and MSCI 499,
Directed Undergraduate Research in Discovery Bay, Jamaica, 14
–31 May 2014. Contact e-mail: mmesch@coastal.edu
INTRODUCTION
CORAL REEFS are one of the most highly productive
ecosystems on the planet. Their biological diversity
makes them crucial to the survival of tropical marine eco-
systems (Hoegh-Guldberg 1999). Coral reefs throughout
the Caribbean have several factors inhibiting the population
growth of many species. Overfishing, coral bleaching, sea-
level rise, predation, and hurricane damage are some short
term and long term conditions that weaken the development
of reefs which inhibit them to remain at a diversity equilib-
rium suited for this environment. The reefs of Discovery
Bay in northern Jamaica have shifted population dominance
over the 20th century from coral dominant to macroalgae
dominant due to natural and anthropogenic events (Idjadi et
al. 2006).
Hurricane Allen impacted the Discovery Bay area in
1980, affecting the coral reef communities in Jamaica. It
had been over 60 years since the last large hurricane hit
Discovery Bay. Prior to the destruction of the hurricane, the
percent cover of corals in the fore reef was 54% at a depth
of 30 m (Houston 1985). Immediately after impact, the
coral coverage was reduced to only 10% (Moses 2008).
Idjadi et al. (2006) found the percent coral cover in Dairy
Bull to be 23%, and increased to 54% after another nine
years in 2004. However, the coral coverage in the west
forereef did not recover as well as Dairy Bull. The west
forereef has had more time to recover and diversify its pop-
ulations since the Idjadi et al. (2006) study was conducted,
with fewer major resilience factors (events causing stress to
the corals) inhibiting the growth and production of the eco-
system.
Coral bleaching is another inhibiting factor that has
influenced the reefs at Discovery Bay. Bleaching occurs
when a coral’s thermal tolerance is exceeded (Hoegh-
Guldberg 1999). In 2005, the Caribbean experienced a
mass bleaching event. During this time, the temperature of
the shallow waters that the corals live in increased past the
thermal tolerance of the corals. This thermal stress stops the
process of photosynthesis within the organism causing it to
lose its color by releasing zooxanthellae making the body
of the coral turn white. All corals within Crabbe’s (2010)
study showed a significant decrease in abundance follow-
ing the bleaching event. Prior to this event, they had con-
sistently been recovering since Hurricane Allen (Crabbe
2010). Potential sea temperature rise throughout the 21st
century by 1–2°C could be extremely detrimental to coral
reefs (Hoegh-Guldberg 1999). The decline of reef systems
will also decrease tourism and fishing in tropical communi-
ties which will be detrimental to the success of local com-
munities that are dependent on funds from these sectors.
Over the summer of 1983, nearly the entire population
of Diadema antillarum died in a mass mortality event
caused by disease. The black spiny sea urchin had popula-
tions up to 71 urchins per m². A waterborne disease, dis-
tributed throughout the Caribbean by ocean currents infect-
ed and killed the urchins within 10 days (Moses 2008).
With this die off of the urchins, the algal population in-
creased rapidly. The urchins had been the primary herbi-
vores of the reef ecosystem in Discovery Bay; keeping a
population balance between the macroalgae and the corals.
The macroalgae coverage at shallower depths of the reef
KORALLION. VOL 5. 2014 5
16. increased nearly 20% between 5–15 m (Liddell and Ohl-
horst 1986).
Overfishing has also become a major issue effecting the
algae population on the reef. With the high fish demand in
Jamaica, local fishermen have stressed the fish populations.
With the decline in numbers of herbivorous fish and the
near extinction of the D. antillarum in Discovery Bay, the
algae community has taken over new niches on the reefs
(Moses 2008).
The diversity of coral correlates with the light gradient
in the water. All corals need sunlight to survive and photo-
synthesize, so the species richness decreases with depth.
Alves de Guimaraens et al. (1994) found that in Discovery
Bay the maximum diversity occurs at 6 m where the envi-
ronmental conditions are most favorable.
In the Idjadi et al. study in 2006, the fore reef of the bay
had a coral coverage of 15% and 60% coverage of algae.
However, at Dairy Bull the coral coverage is much higher
at 43% with an algae cover of only 6%.
Concluding this study, reef coverage and species rich-
ness was determined to show change in diversity. The cov-
erage of the two reefs, the fore reef and Dairy Bull, were
compared to past studies conducted in the same locations to
see if the reefs at Discovery Bay have continued to recover
since 2006.
METHODS
This study was conducted at two different sites near the
Discovery Bay Marine Lab; Dairy Bull and the west fore-
reef. Data was collected from May 19–24 of 2014. Both
sites had the same growth factors such as light, food, and
water quality. Both were less than 1 km off the shoreline
and had easy access to the DBML for frequent data collec-
tion. The reef complexity is similar at both sites, however
depths vary. The reef at Dairy Bull is essentially a constant
same depth because it is on a flatter shelf. Only one transect
of quadrats was collected starting at 7 m and continuing to
9 m. This data was included in the total coverage averages,
but was also separated and compared to the west fore reef.
The west fore reef was around 600 m long and provided
many sub-sites for research (Figure 1). Dairy Bull which,
was similar in length at 500 m, (Idjadi et al. 2006), but on
the opposite side of the channel was also used to collect
data.
Transects were placed parallel and perpendicular to the
shoreline between 3–12 m depth. A 1 m × 1 m quadrat
started at zero meters on each transect and then skipped one
meter before the next quadrat was placed. Pictures of each
quadrat were taken, along with pictures of each species
within the quadrat. Percent coverage of all four substrates
(coral, macroalgae, sponge, bare) were recorded and at
which depth the quadrat was placed. When considering
dead or bleached corals, these were represented as bare
coverage and not included in coral coverage. Data was col-
lected from 11 transects totaling 83 quadrats. Quadrat
depths were rounded to 3 m, 7 m, 9 m, and 12 m. This was
done to eliminate error when recording depth and to com-
pare more easily to other studies. Averages and standard
deviations were calculated to determine complete reef cov-
erage. Species richness refers to the number of species in a
community. For this study, the species richness showed the
number of species at each depth, as well as the change in
richness from shallow to mid-depth water.
RESULTS
The percent coverage of coral and algae changed with
depth (Figure 2). At 3 m corals dominated the reef with
25% coverage and algae covered only 6%. At 7 m the cov-
erage was very similar for coral and algae; coral was at
27% coverage and algae was at 29% coverage. At a depth
of 9 m, algae began to dominate the reef at 60% coverage
and coral only covered 14% of the reef. At the deepest rec-
orded depth of 12 m, algae still dominated the reef with a
coverage percent of 65% and coral was only at 12%. The
remaining coverage percentage at each depth was from the
averages of the bare substrate and sponges, but were not
important to this study.
When totaling the coverage at all depths, the overall
coverage of the forereef between 3 m and 12 m is algae
dominated (Figure 3). Algae coverage was 41% and coral
coverage was 20%. This data included the transect from
Dairy Bull.
The species richness of corals of Discovery Bay in-
creases from 3 m to 7 m and then is consistent up to 12 m
deep (Table 1). Some species of coral change with depth.
Porites astreoides and Acropora palmata were abundant in
shallow waters, whereas Meandrina meandrites, Scolymia
spp. and Dichocoenia spp. were only found in the mid-
waters (Table 1). At Dairy Bull, the average percent cover-
age was 42% and the average algae coverage was 6%
(Figure 4). This reef was a coral dominated reef.
Figure 1. The two locations of the reef survey, the forereef and
Dairy Bull.
ESCH: CORAL COVERAGE AND DIVERSITY6
17. fishing sanctuary within the bay in 2010. Research is cur-
rently being conducted on the effectiveness of the sanctu-
ary, but this may allow the population of herbivorous fish
to increase inside of the bay and eventually migrate out to
the forereef. Lastly, the amount of time since the last large
bleaching event has allowed the shallow water corals to
rebound and become more abundant.
Overall the forereef coverage of coral has increased
from 15% to 20% (Idjadi et al. 2006). This indicates that
the reef is on the verge of transitioning from an algal state
to a coral state, and within the next decade may become a
coral dominated reef. The data of the reef at Dairy Bull
showed that the percent coverage of coral was 43%, which
was a decrease of 12% since 2006 (Idjadi et al. 2006).
However, this may be because only one transect was taken
at Dairy Bull. If time and transportation had allowed further
data collection on this reef, than the results may be more
similar to previous studies.
Species richness increased to 3 m but was then continu-
ous until 12 m. The peak diversity was found at 7 m. Alves
de Guimaraens et al. (1994) found similar results with a
maximum diversity at 6 m. This supports the hypothesis of
the coverage transitional zone as competition between cor-
als and macroalgae at this depth is optimal. Looking at the
corals that are found only in shallow waters such as D. stri-
gosa and A. palmata these must require a higher intensity
of light than corals found in the mid-water such as M. me-
andrites and E. fastigiata. Further studies could compare
deeper waters to determine the effects of sunlight on coral
diversity.
Overall, this study supported Idjadi et al. (2006) in
showing that the forereef at Discovery Bay is still under an
algal dominance. In future years this may change to a coral
dominated reef depending on the inhibiting factors dis-
cussed throughout this study. The species richness hypothe-
sis was supported with the data collected and was also con-
sistent with the other studies discussed in this paper.
Figure 2. Reef coverage averages at each depth gradient of the
forereef. Error bars show the standard deviation of each coverage
category.
Figure 3. Percent coverage of the forereef between 3 m and 12 m.
Error bars show standard deviation.
Figure 4. Reef coverage at Dairy Bull. Error bars show standard
deviation.
DISCUSSION
In the 3 m water region of this study, coral dominated
the reef with almost 5 times greater the coverage than al-
gae. At 7 m depth the coverage of both algae and coral was
just below 30%. This is the transition depth for reef domi-
nation. Beyond 7 m the reef is algae dominated with >60%
coverage until 12 m depth.
A few factors can be taken into account for the coral
domination in the shallow waters on the reef. In 2006,
Bechtel et al. found that the D. antillarum population occu-
pied a percent area of 32% from a nearly 0% coverage after
the mortality event in 1983. The return of the urchin popu-
lation has controlled the abundance of macroalgae on the
rocky substrates in the shallow waters of the reef (Alves et
al. 2003). Another influence was the introduction of the
KORALLION. VOL 5. 2014 7
18. ACKNOWLEDGEMENTS
I thank all of the staff at the Discovery Bay Marine Lab
who all helped me with my study in a variety of ways. A
special thank you to the boat crew D Scarlett, O Holder, D
Edwards for assisting with diving. The entire Coastal Caro-
lina University group for supporting and encouraging pro-
gress with my study. My mom for using her credit card.
Lastly, my dive buddy A Baldwin for helping collect my
data and holding my unruly quadrat when needed.
Depths 3 m 7 m 9 m 12 m
Siderastrea radians +++ ++ +++ +++
Siderastrea siderea +++ ++ +
Porites astreoides +++ +++ +++
Porites porites +++ + ++ +++
Montastraea annularis +++ +++ +++
Montastraea
cavernosa
+ + +++
Agaricia agaricites +++ +++ +++ +++
Agaricia fragilis +
Millepora complanata +++ ++ + +
Millepora alcicornis + +
Eusmilia fastigiata + + ++
Meandrina meandrites + + +++
Scolymia spp. +
Dichocoenia spp. +
Diploria
labyrinthiformis
+ ++ ++
Diploria strigosa +++ ++ +
Colpophyllia natans ++
Isophyllastrea rigida + +
Madracis decactis +++ +++ +++ +++
Madracis auretenra ++ + ++
Acropora palmata +
Total: 11 16 15 15
Table 1. Species richness at depth gradients and all species abun-
dance found at each depth. Abundant (+++): >20%, common
(++): 2–19%, and rare (+): <2%.
LITERATURE CITED
Alves de Guimaraens M, Corbett C, Combells C. 1994. Species
diversity and richness of reef building corals and macroal-
gae of reef communities in Discovery Bay, Jamaica. Acta
Biologica Leopoldensia. 16(1): 41-50.
Alves F, Chicharo L, Serrao E, Abreu A. 2003. Grazing by Di-
adema antillarum (Philippi) upon algal communities on
rocky substrates. Sci Mar. 67(3): 307-311.
Andres N, Witman J. 1995. Trends in community structure on a
Jamaican reef. Mar Ecol Prog Ser. 118: 305-310.
Bechtel J, Gayle P, Kaufman L. 2006. The return of Diadema
antillarum to Discovery Bay: Patterns of distribution and
abundance. Proceedings of 10th International Coral Reef
Symposium. 367-375.
Crabbe M. 2010. Coral ecosystem resilience, conservation and
management on the reefs of Jamaica in the face of anthropo-
genic activities and climate change. Diversity. 2: 881-896.
Hoegh-Guldberg O. 1999. Climate change, coral bleaching and
the future of the world’s coral reefs. Mar Freshwater Res.
50: 839-866.
Huston M. 1985. Patterns of species diversity in relation to depth
at Discovery Bay, Jamaica. Bull Mar Sci. 37(3): 928-935.
Idjadi J, Lee S, Bruno J, Precht W, Allen-Requa L, Edmunds P.
2006. Rapid phase-shift reversal on a Jamaican coral reef.
Coral Reefs. 25(2): 209-211.
Liddell W, Ohlhorst S. 1986. Changes in benthic community
composition following the mass mortality of Diadema at
Jamaica. J Exp Mar Biol Ecol. 95: 271-278.
Moses C. 2008. Field Guide for Geology and Biology of Jamaican
Coral Reefs. SCUBAnauts International. 1-23.
ESCH: CORAL COVERAGE AND DIVERSITY8
19. Samantha M. Cook
Department of Marine Science, Coastal Carolina University, PO Box 261954, Conway, SC 29526
ABSTRACT
Discovery Bay, Jamaica presents a localized model of severe over-fishing to a coral reef ecosystem. In 2010, Discov-
ery Bay implemented a fish sanctuary with the hopes of rebuilding the fish stock within the bay. This study aimed to assess
differences between the fish communities within the sanctuary and the unprotected forereef using the Roving Diver Tech-
nique. 19 surveys lasting 20 minutes each were completed over the course of nine days. seven were performed within the
protected sanctuary and 12 were performed in the unprotected forereef. From this, percent sighting frequency, density
score, and abundance score were calculated and compared using a one-way ANOVA. It was found that there was no signifi-
cant difference between the surveys taken within and outside the bay. The size and number of four fish species important
to the fishery were also observed to see whether fish inside the sanctuary are reaching maturity. While the size data could
not be used, it was found that there was no significant difference between number of Sparisoma viride, Scarus taeniopterus,
or Cephalopholis cruentatas within two zones. There was a significant difference between the number of Haemulon sciu-
rus. This is thought to be due to their nocturnal migration. An ordination plot shows independent clustering of the two com-
munity structures. While it cannot be said with certainty that recovery to the fish stock is occurring, a difference in the com-
munity structure between the two areas was observed.
KEYWORDS: diversity, abundance, over-fishing, roving diver technique, Haemulon sciurus
This research was conducted as part of Coastal Carolina Universi-
ty’s classes MSCI 477, Ecology of Coral Reefs, and MSCI 499,
Directed Undergraduate Research in Discovery Bay, Jamaica, 14
–31 May 2014. Contact e-mail: smcook@coastal.edu
INTRODUCTION
CORAL REEFS offer one of the most biologically di-
verse ecosystems on the planet, with an estimated
biodiversity of 1–9 million species (Knowlton 2001). Dis-
covery Bay, Jamaica is dominated by some of the most
studied reefs anywhere in the Caribbean. The north shore
has a macroalgae- dominated fringing reef that runs 1.2 km
along Discovery Bay (Gayle and Woodley 1998). The bay
itself has a deep water channel in the center with shallow
sandy lagoons surrounding it, along with scattered coral
heads and patch reefs (Gayle and Woodley 1998). Over
the years these reefs have been marked with a series of
large-scale disturbances including Hurricane Allen in
1980, Hurricane Gilbert in 1988, and a continuous decima-
tion of herbivorous fish populations due to overfishing
(Andres and Witman 1995). Over-exploitation of fisheries
is not limited to just Jamaican waters but it is also seen as a
worldwide problem. Pauly et al. (1998) states that this
global crisis is due to economics and governance with a
natural fluctuation that is driven by demand. This fluctua-
tion, along with a lack of regulation and management, can
result in severe over-fishing of coral reefs.
While this occurs worldwide, Jamaica is a clear local-
ized model. The Jamaican near-shore fishery is mainly
artisanal, consisting of open canoes and swimmers who use
traps, hook-and-line, spears, and gill-nets (Andres and Wit-
man 1995). The intense local fishing has caused the Jamai-
can north coast coral reef to be among one of the most
overfished reefs in the English-Speaking Caribbean
(Andres and Witman 1995). Instead of quality fish such as
grouper and snapper, smaller, younger fish of other species
are being captured, and as a result, the breeding stock is
being seriously damaged (Woodley and Sary 2000). Haw-
kins and Roberts (2004) measured that the fishing intensity
around Discovery Bay (fishers/km reef) is 7.14, more than
double the next greatest (St. Lucia at 3.23). The Jamaican
fisheries are economically driven, however, they produce a
very low economic return. In 1988, the Discovery Bay Ma-
rine Lab implemented the Fisheries Improvement Program,
which aimed to work with and educate local fishermen with
the goal of hopefully implementing fishery management
measures. In 1994, the Alloa Discovery Bay Fishermen’s
Association agreed to section off an area of shallow water
on the west side of the bay which became known as the
Discovery Bay Fisheries Reserve. The success of the Re-
serve, shown by rebounding fish numbers, drove a petition
for its expansion and the desire to eventually change it into
a Fish Sanctuary. Unfortunately, after 1998 a lack of funds
made it impossible for a patrol to enforce the protection of
the bay and the indicators of overfishing once again began
to occur (Woodley and Sary 2000).
In 2010, the Ministry of Agriculture and Fisheries
stepped in along with seven state and non-governmental
OBSERVING THE EFFECTIVENESS OF THE DISCOVERY BAY FISH
SANCTUARY USING REEF SURVEY TECHNIQUES
KORALLION. VOL 5. 2014 9
20. bodies, including the Alloa Discovery Bay Fishermen’s
Association, to create a community-based movement that
would create nine fish sanctuaries on the island (Jamaican
Information Service 2010). These sanctuaries, including
Discovery Bay, were deigned as no fishing zones for the
protection of juvenile fish in hopes of rebuilding the fish
population to sustainable levels. They are considered Spe-
cial Fishery Conservation Areas (SFCA) under Section 18
of the Fishing Industry Act of 1975 and, as such, unauthor-
ized fishing activities within them are punishable by law.
The Discovery Bay Fish Sanctuary consists of every-
thing south of Old Man Head on the west forereef to Fort
Port on the east forereef. The fringing reef located outside
of the bay does not fall under protection and artisanal fish-
erman launch daily from the southeastern corner of the bay
as well as from the fishermans’ beach near the Discovery
Bay Marine Lab to fish the surrounding area outside of the
bay. The Discovery Bay Fish Sanctuary and its surrounding
reef presents the opportunity to study two similar over-
fished environments in which one has been changed in an
attempt to remedy the problem.
The focus of this study was to observe fish popula-
tions in two areas of Discovery Bay using the Roving Div-
er Technique. To determine the effects of overfishing, as
well as add on to an existing database, the fish survey was
conducted using the Reef Environmental Education Foun-
dation’s guidelines on a number of dive sites both in the
Fish Sanctuary and on the fringing reef surrounding the
boundaries of the bay. It was suspected that a more diverse
population with larger and older fish will be within the Fish
Sanctuary and that the surrounding fringing reef would
contain a less diverse population consisting of younger
fish.
Discovery Bay has played a key role in the regulation
of fisheries that make up Jamaica’s waters. The 2010 ac-
tion to make the inner bay a fish sanctuary while keeping
the surrounding area open to local fishermen presents the
unique opportunity to measure on how effectively the plan
has been to rebuild the fish population.
METHODS
Nineteen REEF surveys were conducted over nine
days during May 2014 at the Discovery Bay Marine Lab,
Jamaica. Locations of dive sites were split between pro-
tected and unprotected areas within and surrounding the
bay.
The fish survey was conducted using the Rover Div-
ing Technique (RDT). The Reef Environmental Education-
al Foundation favors this technique because it is unobtru-
sive and does not require many tools to get an accurate
reading on the fish population (Pattengill-Semmens and
Semmens 2003). It is especially useful for coral reefs
where fish are easily recognizable by distinctive markings
(Schmitt and Sullivan 1996). At each dive site, observa-
tions were made freely and each fish species seen was rec-
orded using a REEF identification slate. Because of time
constraints, surveys only occurred during the day. Each fish
was recorded based on four log10 abundance categories.
These include: single (1), few (2–10), many (11–100), and
abundant (>100) (Pattengill-Semmens and Semmens 2003).
At the end of the campaign, the survey data was submitted
to REEF via an online form. At the completion of each
dive, the dive site name, survey start time, visibility, aver-
age depth, water temperature, and habitat type was all rec-
orded for later analysis. Table 1 shows the name of the dive
site, the number surveys performed at the site, the average
depth, the total time, and the total species seen (Schmitt and
Sullivan 1996).
Sizes and specific counts of observed princess parrot-
fish (Scarus taeniopterus), Graysby grouper
(Cephalopholis cruentatus), French grunts (Haemulon
sciurus), and stoplight parrotfish (Sparisoma viride) were
also recorded. They were measured in approximations of 5
centimeters to respect the unobtrusive nature of a REEF
fish survey.
The data collected in the surveys was observed in
three sections, (1) total data gathered, (2) information gath-
ered outside of the bay, and (3) information gathered within
the fish sanctuary. Analysis was based off of REEF analy-
sis techniques as well as a more in depth statistical analysis.
Percent sighting frequency, density score, and abundance
score were calculated to observe the effectiveness of the
sanctuary. Percent sighting frequency (%SF) is the percent-
age of all dives in which the species or family was record-
Surveys
(no.)
Total
time
(min)
Avg.
depth
(m)
Total
species
Unprotected
Rio Bueno 1 20 27
M1 2 40 6.1 32
Shallow LTS 2 40 6.1 36
Dancing
Lady
3 60 6.1 40
LTS 3 60 6.1 41
Dairy Bull 1 20 9.1 30
Protected
Dorm Shore 2 40 12.1 32
Red Buoy 2 40 12.1 31
East Back
Reef
1 20 6.1 33
Back Reef 1 20 3 20
Little Blue
Hole
1 20 9.1 23
Table 1. Number of surveys performed at each site including total
observation time, average depth, and the total species counted.
The average depth at Rio Bueno was not collected.
COOK: FISH SANCTUARY EFFECTIVENESS10
21. DISCUSSION
The hypothesis stated at the beginning of the survey
predicted a more diverse population (with larger and older
fish) within the Fish Sanctuary than that of the surrounding
fringing reef, which was believed to contain a less diverse
population consisting of younger fish. Unfortunately, the
limited amount of size data collected within the time con-
straints made it unreliable to be used as a proxy for age. It
is to be noted though, that larger fish, especially princess
parrotfish and stoplight parrotfish, were seen within the bay
consistently at both Red Buoy and Dorm Shore. These ob-
servations imply that juvenile fish are able to reach maturi-
KORALLION. VOL 5. 2014
ed. It was calculated using the formula:
%SF= Dives species or family was recorded/Total
number of dives
Density score (Den) is the weighted average index
calculated for each family based on the frequency of obser-
vation in different abundance categories. It was calculated
as:
Den=((S)+(2F)+(3M)+(4A))/S+F+M+A
in which S, F, M, and A all represent frequency categories
(single, few, many, and abundant, respectively) and n is
equal to the total number of dives. This number is between
1 and 4 and indicates the abundance value of each species.
Abundance score (%SF x Den) was used to account for
density, frequency of occurrence, and zero observations
(Schmitt and Sullivan 1996). A statistical review examin-
ing %SF, density score, and abundance in protected and
unprotected areas was preformed using a one-way ANOVA
(Schmitt and Sullivan 1996 ). %SF was also observed for
the overall population. Species were divided into three cat-
egories: frequent (≥ 70%), common (7%<x<20%), and un-
common visitors (>20%).
Efficiency was examined (by clustering) using an or-
dination plot to observe community structure, species rich-
ness, and Simpson and Shannon diversity indexes. A stress
value, between 0 and 1, was calculated an indication of the
amount of scatter between points in the ordination plot.
Stress values below 0.2 are considered to give a relatively
accurate picture of the arrangement of data. The population
in relation to number of specific fisheries in the two areas
was assessed using the one-way ANOVA test.
RESULTS
Over the course of nine days, 11 sites were examined
for a total of 380 minutes. Of the 11 sites, five were within
the protected zone of the bay while six were on the unpro-
tected fore reef. At the end of the survey, the unprotected
zone had been surveyed for 240 minutes and the protected
zone for 140 minutes. The data from both sites was used to
discern the overall % sighting frequency. Within the 11
sites, 79 species were observed. Of these, 11 species were
considered to be frequent, 32 species were considered to be
common, and 24 species were considered uncommon visi-
tors (Table 2). A one-way ANOVA showed that there was
no significant difference between the protected and unpro-
tected zones in regards to % sighting frequency (p = 0.23),
density score (p = 0.30), or abundance score (p = 0.36).
While sizes of princess parrotfish, stoplight parrotfish,
Graysby grouper, and French grunt were observed, it was
determined that not enough information had been gathered
to make any reliable observations. Instead, the number of
each species inside and outside of the bay was compared by
way of a one-way ANOVA. It was seen that there was no
significant difference for the princess parrotfish (p = 0.47),
the stoplight parrotfish (p = 0.47), or the Graysby grouper
(p = 0.29). The abundance of French grunt was statistically
different with a p-value of 0.04.
An ordination plot was used to compare the similarity
of the community structure between the protected and un-
protected areas. It can be seen in Figure 1 that there is clear
separation between the two, with clustering occurring for
the protected and unprotected zones independent of one
another. The ordination value had a stress value of 0.14 and
from this the Simpson Diversity Index was also calculated.
The unprotected zone had an average of 0.77 while the pro-
tected zone had an average of 0.85. A one-way ANOVA
showed that there was a statistical significance between the
two (p = 0.01). The breakdown of diversity for each site
can be seen in Table 3. The Shannon Diversity Index was
also calculated. The protected zone had an average of 2.4
while the unprotected zone had an average of 2.3. A one-
way ANOVA showed that there was no significant differ-
ence between the two (p = 0.34) (Table 3). Species richness
was calculated as well. The protected zone had an average
of 23.87 while the unprotected zone had an average of
26.67 (Table 3). A one-way ANOVA showed that there
was no significant difference between the two.
11
Figure 1. Ordination plot showing independent clustering of the
community structures inside and outside of the sanctuary. A stress
level of 0.14 was found. Diamonds represent inside the bay, while
squares represent outside the bay.
23. cate a rebounding fish stock. It was seen that there was no
statistical difference between the princess parrotfish, stop-
light parrotfish, or Graysby grouper but there was statistical
significance seen between the French grunt population
within the protected and unprotected zones. While fishes
belonging to the family Haemulidae are severely overfished
in Jamaica, it’s believed that more French grunts were seen
within the bay primarily due to the time when the surveys
occurred. Grunts are nocturnal predators who leave the bay
to forage on the forereef and surrounding sandflats at night
(Burke 1995). Because all surveys occurred during the day,
few grunts were seen on the fore reef and larger schools
were seen within the bay. The correlation between the pro-
tected zone and the number of French grunts cannot be
determined with certainty because of this nocturnal migra-
tory pattern.
A similar, long-term monitoring project is occurring
in Oracabessa Bay, a designated fish sanctuary also located
on Jamaica’s northern coast. In October 2011, a baseline
survey was completed within the sanctuary. They also
found a high biomass of parrotfish (159 g/100 m2
) and sur-
geonfish (39.85 g/100 m2
) with lower biomasses within the
grunts and groupers (1.93 g/100 m2
and 14.99 g/100 m2
respectively) (Anonymous 2011). An examination of size
showed that parrotfish, grunts, and groupers fell into the
juvenile to sub-adult class ranges, most likely due to over-
fishing. In 2012, a follow up showed that within the sanctu-
ary there was a 287.2% change in the fish biomass and a
15.95% change in the overall size of the fishes
(Anonymous 2012). This implies that with a larger data
pool, the sanctuary at Discovery Bay may also show similar
results indicative of recovery.
An ordination plot was used to look at the similarity
of the community structures between the protected and
unprotected areas in Discovery Bay. As seen in Figure 1,
there is a clear separation between the two. The low stress
value of 0.14 indicates that the fish communities sustained
within each are significantly different. The Simpson Diver-
sity Index was also calculated, and a one-way ANOVA
showed that the biodiversity between the protected and
unprotected areas was different. However, the species rich-
ness and Shannon Diversity Index did not show a signifi-
cant difference. A further insight to the makeup of the fish
communities within the two areas would need to be deter-
mined before a conclusion was made about the similarity of
diversity between the two locations.
ACKNOWLEDGMENTS
This study could not have been completed without the
continuous help of the Discovery Bay Marine Lab. Special
thanks to the dive team who got us where we needed to be
and kept an ever-optimistic attitude. Thank you also to Dr.
E Burge whom was forever patient with my never-ending
stream of questions. Thanks to B Hinze who was the most
amazing dive buddy a person could ask for and to all the
Table 3. Species richness, Shannon Diversity Index, and Simpson
Diversity Index for each survey performed within the protected
and unprotected zones. There was statistical significance seen
between the Simpson Diversity Index within and outside the bay
but not for the Species Richness or the Shannon Diversity Index.
ty within the sanctuary. This is promising as Hughes (1994)
discussed that over the last 30 to 40 years that herbivores
such as scarids (parrotfish) and acanthurids (surgeonfish)
have increased in number over predatory species, but de-
creased in size. This is seen especially along north shore,
where half the species are caught below the minimum re-
productive size (Hughes 1994). Further surveys consisting
of longer than the 20-minute maximum time should be tak-
en to get a more accurate idea of the general size of the
fishes within the bay.
In place of age proxy by size, the overall count of
individual fish belonging to certain fisheries was analyzed
in hopes of seeing a larger number within the bay to indi-
KORALLION. VOL 5. 2014 13
Species
Richness
Shannon
Index
Simpson
Index
Unprotected
5/17 Rio Bueno 27 2.2 0.92
5/17 M1 25 2.1 0.92
5/18 M1 34 2.1 0.75
5/18 Shallow LTS 33 2.4 0.82
5/20 Dancing Lady 32 2.4 0.93
5/20 Shallow LTS 25 2.3 0.94
5/21 LTS 20 2 0.93
5/21 Dancing Lady 28 2.3 0.79
5/23 Dancing Lady 28 2.3 0.78
5/23 LTS 34 2.3 0.74
5/24 Dairy Bull 30 2.1 0.78
5/25 LTS 28 2.9 0.94
Average 28.7 2.3 0.85
Protected
5/25 Dorm Shore 19 2.6 0.79
5/23 Dorm Shore 23 1.2 0.74
5/24 Red Bouy 25 2.1 0.78
5/25 East Back Reef 33 2.2 0.83
Back Reef 23 2.8 0.79
5/27 Little Blue Hole 22 2.8 0.8
5/27 Red Bouy 22 2.8 0.8
Average 23.9 2.4 0.79
24. participants of the 2014 Jamaica Maymester who made this
experience unforgettable. Finally, thank you to my parents
for supporting me through this entire endeavor.
LITERATURE CITED
Anonymous. 2011. Oracabessa Fish Sanctuary Baseline
Survey Assessment. 2011, October. National Environ-
mental and Planning Agency. Available from http://
www.oracabessafishsanctuary.org/
oracabessa_bay_sanctuary_legal_documents_files/
NEPA%20Baseline%20info.pdf
Anonymous. 2012. Oracabessa Bay Fish Sanctuary: Year 2- Sum-
mary Report. National Environmental and Planning Agency.
Available from http://www.oracabessafishsanctuary.org/
oracabessa_bay_sanctuary_legal_documents_files/
OBFS%202011%20Monitoring%20Data.pdf
Andres NG, Witman JD. 1995. Trends in community structure on
a Jamaican reef. Mar Ecol Prog Ser. 118:305-310.
Burke NC. 1995. Nocturnal foraging habitats of French and
bluestriped grunts, Haemulon flavolineatum and H. sciurus,
at Tobacco Caye, Belize. Environ Biol Fish. 42(4): 365-374.
Hawkins JP, Roberts CM. 2004. Effects of artisanal fishing on
Caribbean coral reefs. Conserv Biol. 18(1): 215-226
Hughes TP. 1994. Catastrophes, phase shifts, and large-scale deg-
radation of a Caribbean coral reef. Science. 265(5178): 1547
-1551.
Knowlton N. 2001. The future of coral reefs. Proc Natl Acad Sci
USA. 98(10): 5419-5425
Jamaican Information Service. 2010. No-fishing zones established
under marine-protection MOU. The Gleaner. Retrieved from
http://jamaica-gleaner.com/gleaner/20101212/business/
business4.html
Pattengill-Semmens CV, Semmens BX 2003. Conservation and
management applications of the REEF volunteer fish moni-
toring program. Environ Monit Assess 82: 43-50.
Pauly D, Christensen V, Dalsgaard J, Froese R, Torres F. 1998.
Fishing down marine food webs. Science. 279 (5352): 860-
863.
REEF. (2014) Geographic Zone Report. Retrieved from http://
www.reef.org/db/reports/geo/twa/53030028
Schmitt EF, Sullivan KM (1996). Analysis of a volunteer method
for collecting fish presence and abundance data in the Flori-
da Keys. Bull Mar Sci. 59(2): 404-416.
Special fishery conservation areas (SFCA). 2014. Web. 4 Mar
2014. Available from: http://www.moa.gov.jm/Fisheries/
fish_sanctuary.php
COOK: FISH SANCTUARY EFFECTIVENESS14
25. KORALLION. VOL 5. 2014
DENSITY, RESIDENCE TIME, AND INDIVIDUAL ASSOCIATION OF
FLAMINGO TONGUE SNAILS (CYPHOMA GIBBOSUM) ON GORGONIAN HOSTS
Catharine C. Gordon
Department of Marine Science, Coastal Carolina University, PO Box 261954, Conway, SC 29526
ABSTRACT
The relationship between Cyphoma gibbosum and their gorgonian hosts is a parasitic relationship. Cyphoma gibbosum
use the gorgonians as a food source, mating grounds, and substrate for egg deposition. This study increases knowledge of
the density of both C. gibbosum and their gorgonians hosts in Discovery Bay, Jamaica. The movement of the snails in terms
of residence time and association between snail pairs was examined. Samples were taken on the west forereef by SCUBA
diving. Thirteen, 8 m diameter sites were sampled and snails were marked with a microfile to track their movement. Over
the 653.45 m2
sampled, a total of 138 gorgonians and 13 C. gibbosum were observed. On average, there were 21.1 gorgoni-
ans per 100 m2
(±13.0). The gorgonian species Gorgonia flabellum was most abundant over the sample area (15.6 individu-
als per 100 m2
± 8.3). On average, there were 2.9 C. gibbosum individuals per 100 m2
(±1.0). A majority of the C. gibbo-
sum were found on G. flabellum. The residence time of the snails on a gorgonian individual ranged from 2 to 4 days. While
snails were found individually a majority of the time, there was an overall significant association between snail pairs ob-
served meaning they tended to move together.
KEYWORDS: Flamingo tongue, gorgonians, parasitism, micropredation, Discovery Bay
This research was conducted as part of Coastal Carolina Universi-
ty’s classes MSCI 477, Ecology of Coral Reefs, and MSCI 499,
Directed Undergraduate Research in Discovery Bay, Jamaica, 14
–31 May 2014. Contact e-mail: ccgordon@coastal.edu
INTRODUCTION
GORGONIAN CORALS are commonly found in tropical
shallow waters (4–10 m) in groups with multiple spe-
cies (Gerhart 1990). The primary factors which determine
the distribution of gorgonians are water movement, light,
and availability of firm substrate for settling (Kinzie 1973).
In water depths 3–9 m Gorgonia flabellum (Linnaeus,
1758), Plexaurella homomalla (Esper, 1792), and Plexaura
flexuosa (Lamouroux, 1821) are very abundant (Kinzie
1973).
Gorgonian morphology serves to maximize surface
area (Leversee 1976); G. flabellum are a large, flat and foli-
ose species and P. flexuosa have branching patterns allow-
ing them to increase their surface area. All species of gor-
gonians are loosely flexible, an adaptation which allows
them to move back and forth in the water column. Gorgoni-
ans generally orient themselves perpendicular to the domi-
nant hydrodynamic factors; this allows them to sway back
and forth in the water column and filter feed (Leversee
1976).
One of the most common gorgonian predators is the
ovulid gastropod, Cyphoma gibbosum (Linnaeus, 1758),
also known as the flamingo tongue snail (Chiappone et al.
2003). Cyphoma gibbosum are relatively small (2.5 cm
long) and most commonly found in the sub-tidal zone
(Gerhart 1986, Nowlis 1993). Flamingo tongue snails have
a pale yellow shell and a brown spotted mantle. When un-
disturbed, these snails extend their mantle up and around
their shell covering it completely. These gastropods feed on
the axial tissue and polyps of the gorgonians causing partial
colonial mortality (Chiappone et al. 2003). Gorgonians also
provide protection and serve as grounds for mating and egg
deposition for C. gibbosum (Lasker et al. 1988).
Cyphoma gibbosum gorgonian grazing habits have
notable control over the abundance of the coral population
(Lasker and Coffroth 1988). Snail populations typically
remain relatively constant with a small increase in the sum-
mer months. Because the C. gibbosum population is gener-
ally unchanging, grazing activity is also relatively constant
(Lasker and Coffroth, 1988). The grazing on the gorgoni-
ans exposes their axial skeletons leaving behind a feeding
scar discolored from the surrounding tissue (Gerhart 1990).
The exposed skeleton allows greater diversity on the reef as
it serves as colonization sites for larval organisms and algae
(Gerhart 1990). While the increased diversity is positive,
when the exposed skeleton is colonized it is sometimes
difficult for the tissue to be regenerated and could eventual-
ly cause full death of the gorgonian (Harvell and Suchanek
1987).
This study took place in Discovery Bay, Jamaica from
May 15 through May 27, 2014. Hogfish, Lachnolaimus
maximus (Walbaum, 1792) are natural predators of C. gib-
bosum and have experienced a large population decline
because of the overfishing throughout the reef, which has
15
26. allowed the snail population to increase (Gayle and Wood-
ley 1998, Chiappone et al. 2003). Higher densities of C.
gibbosum can lead to increased feeding on the gorgonian
hosts in turn affecting gorgonian density and growth.
In previous research, there were never more than three
snails on a single gorgonian at one time with majority of
the hosts only occupied by a single snail and only twenty-
eight percent of the surveyed gorgonians had two occupants
(Snyder 2013). Other research found that C. gibbosum are
normally found in pairs, one male and one female
(Chiappone et al. 2003). Associations between snail pairs
will be examined to resolve the discrepancy between
Snyder (2013) and Chiappone et al. (2003).
This study serves to measure the relative densities of C.
gibbosum and their gorgonian hosts. The results found in
this study were added to the data obtained by Snyder
(2013) to gain a more comprehensive picture of the Discov-
ery Bay, Jamaica area. The residence time of individual
flamingo tongue on their gorgonian hosts was measured
and predicted to be around 3.3 days based on Harvell and
Suchanek (1987). Because the study area and time were
closely associated with Snyder (2013), it was predicted
snails will not move together between gorgonians.
METHODS
All sampling occurred in Discovery Bay, Jamaica
along the coral reef where there was a high abundance of
the gorgonian host corals with snails or feeding scars pre-
sent. Because C. gibbosum occur mostly in areas where
water depth is relatively shallow, all sampling occurred in
water 8 m or less. The areas sampled were on the seaward
side of the west forereef at dive locations M1, Dancing
Lady (DL), and Long Term Site (LTS). Using SCUBA
diving, 13 circular sample sites were chosen and labeled 1–
13 (Table 1). Sites were chosen at random at a range of
depths.
Each circular site measured 8 m in diameter. A 4 m
piece of string was tied to a dead piece of coral, with ten-
sion on the string a circle was made around the marked
center point. For each circular sampling site, the number
and species of gorgonian were counted as well as the num-
ber of C. gibbosum. On gorgonians in the sample area
where flamingo tongue were present, the number of snails
per gorgonian was counted.
The depth and a compass bearing relative to the Dis-
covery Bay Marine Lab were also taken per sample site. A
plastic water bottle filled with air was tied to the center
point and labeled with the site number to mark the site.
Density was calculated for flamingo tongue snails, each
gorgonian species, and the gorgonian class overall at each
individual sample site and averaged for the overall sample
area. The percentage of gorgonians occupied by at least one
C. gibbosum was compared with the percentage unoccupied
to determine whether there was a greater majority of hosts
with or without occupants.
Residence time was calculated based on the number
of days an individual flamingo tongue was located on a
particular colony. A marking was etched onto each C. gib-
bosum in the sample area using a microfile. The procedure
used to make the markings was adapted from Lasker et al.
(1988), it entailed picking up an individual gastropod, mak-
ing the appropriate mark, and replacing the snail at the base
of the gorgonian. This procedure was used because, while
the markings are permanent, they do not alter the appear-
ance of the C. gibbosum greatly and they are not harmful to
them (Harvell and Suchanek 1987, Lasker et al. 1988). It
allowed the snails to be handled only briefly and does not
noticeably change their behavior (Harvell and Suchanek
1987). The coral where the flamingo tongue was present
was also marked. Markings were made on the first day of
sampling at each location. In the following days, sites were
revisited to see whether the marked individual had moved
from the original colony.
The number of gastropods per gorgonian was record-
ed to determine whether C. gibbosum move together be-
tween colonies. In the following days, paired individuals
were observed. The number of times the snails were seen
together and the total number of times they were observed
(whether they are together or apart) was recorded. The as-
sociation formula, A1,2 = O1,2 / Omax where A1,2 is the asso-
ciation, O1,2 is the number of times snail 1 was observed
with snail 2, and Omax is the total number of times snail 1 or
2 was observed (whichever was observed more was used)
Site Location
Depth
(m)
Compass Bearing
1 M1 16 210o
NE
2 LTS 17 180o
N
3 LTS 19 200o
NE
4 DL 22 210o
NE
5 DL 14 210o
NE
6 LTS 14 200o
NE
7 DL 18 200o
NE
8 DL 24 180o
N
9 DL 15 220o
NE
10 DL 11 230o
NE
11 LTS 19 200o
NE
12 DL 23 210o
NE
13 DL 17 210o
NE
Table 1. Site number, location, depth, and compass bearing rela-
tive to the Discovery Bay Marine Lab for each randomly chosen
sample site.
GORDON: FLAMINGO TONGUE RESIDENCE TIME16
27. KORALLION. VOL 5. 2014
was used (Lasker and Coffroth 1988). If A1,2 is greater than
0.5 then there is a significant association between the snail
pair. From the pairs, the average A1,2 value and standard
deviation was calculated to see if there was an overall sig-
nificance in the association between gastropod pairs.
RESULTS
A total area of 653.45 m2
was sampled during this
study. In the sample area, a total of 138 gorgonians of five
different species were observed. A total of 13 C. gibbosum
individuals were observed on nine different gorgonian indi-
viduals. Nine C. gibbosum were found on G. flabellum, two
were found on both P. flexuosa and Eunicea sp., and no
snails were found on any other surveyed gorgonians.
On average, there were 21.1 gorgonians per 100 m2
(±
13.0) (average ± standard deviation). Gorgonia flabellum
was most abundant with 15.6 individuals per 100 m2
(±
8.3). Plexuara flexuosa were found with 5.7 individuals per
100 m2
(± 4.4). Pseudoptergorgia sp. and Eunicea sp. were
similarly abundant with 3.0 individuals per 100 m2
(± 1.4)
and 2.1 individuals per 100 m2
(± 1.4) respectively. Plexau-
rella homomalla was least abundant with 0.3 individuals
per 100 m2
(± 0).
On average, there were 2.9 C. gibbosum per 100 m2
(±
1.0). In the sample area, 6.52% of the gorgonians sampled
were occupied by at least one flamingo tongue snail. The
majority of gorgonians in the sample area were not occu-
pied by any snail (93.48%) though many had feeding scars
present.
Because each site was not visited on a daily basis it
was not possible to calculate a residence time for each C.
gibbosum individual, instead a range was calculated for the
Snail Marking 19-May 20-May 21-May 23-May 24-May 25-May 27-May
1 l Intial Absent
2 ll Initial Present Absent Absent
3 llllll Initial Present Present
4 lll Initial Absent
5 llll Initial Absent Absent
6 lllll Initial Present Present
7 lllllll Initial Absent
8 ll/l Initial Absent
9 l/l Initial Present
10 ll/ll Initial Present
11 lll/lll Initial Absent
12 llll/llll Initial Absent
13 lll/lll Initial Absent
overall sample population. The minimum residence time
for the sample population was 2 days while the maximum
residence time was 4 days (Table 2). Of the 13 snails ob-
served, a majority were found on G. flabellum (Figure 2).
No snails were observed on Pseudopterogorgia sp. or P.
homomalla.
Of the thirteen snails observed, four pairs of snails
were observed together. Snails observed together both at
initial marking period and in the following days were con-
sidered to be paired and used to calculate the association
variable (A1,2). The average association variable was 0.708
(± 0.344). Because the average association variable was
greater than 0.5 the data represents a significant association
between the paired C. gibbosum individuals.
DISCUSSION
The results are consistent with the results of Snyder
(2013) as G. flabellum were most abundant and P. flexuosa
second most abundant. Snyder (2013) found the density of
C. gibbosum to be 9.9 individuals per 100 m2
(± 7.7), which
is approximately five times greater than snail density in this
study. This discrepancy is plausible because Snyder sought
out sites where at least one flamingo tongue snail was pre-
sent whereas areas with high gorgonian densities were used
for sites in this study.
Snyder (2013) found a higher abundance of corals to
be occupied by C. gibbosum, 20% compared to 6.52% in
this study. This discrepancy is because Snyder surveyed
more individual sites (26 compared to 13). While the per-
cent occupancy differed greatly, the Gorgoniidae family
was occupied most often in both studies.
Table 2. Table of marked snails and the dates they were observed. Initial represents the day the snail was initially marked, present and
absent in the following days represents the dates the sites were revisited and whether or not the snail was present on the original coral. All
snails were observed between 0700 and 1200. The minimum residence time was 2 days (snail 5) and the maximum was 4 days (snail 3).
17
28. The average number of snails and density of the C.
gibbosum at each site is comparable to the values of flamin-
go tongue snail observed in the Florida Keys (Chiappone et
al. 2003). The density of C. gibbosum in the Florida Keys
ranged from 0 (± 0) to 4.2 (± 1.2) individuals per 100 m2
and there were 2.00 individuals per 100 m2
(± 1.31) on av-
erage (Chiappone et al. 2003). The maximum density from
the Florida Keys was greater than the values in this study,
but the average densities of C. gibbosum are closely relat-
ed.
Since the sample size of gorgonians, flamingo tongue
snails, and the area of the reef sampled were small, the re-
sults could differ greatly if a larger sample was used. The
small sample size could also attribute to the differences
between this study and Snyder (2013). Obtaining a larger
sample size was difficult due to the time constraints of this
study.
The residence time of C. gibbosum ranged from 2 to 4
days, which was a fairly short residence time that supported
the hypothesis of this study. Harvell and Suchanek (1987)
also studied residence time but returned to each site on a
daily basis and had an average residence time of 3.3 days.
Their average residence time falls within the range of this
study confirming the range is accurate. Cyphoma gibbosum
use the gorgonian hosts primarily for food but they also are
used for protection and reproduction. This is because the
snails move searching not only for more food but also for
the most protected colony or one suitable for reproduction.
One pair of snails (numbers 11 and 12) were observed at
the base of coral colony near newly deposited egg cases.
The base of this coral was fairly protected from swimming
predators confirming the movement prediction. The gorgo-
nian serves other purposes than just food, which could be a
reason why the residence time is so short. To improve the
residence time data, in another study, sites would be
marked one at a time and returned to on a daily basis until
the marked gastropods were no longer present. This would
allow the calculation of an individual residence time for
each snail. Observations could be made on the activity of
the gastropods while present on the gorgonian to observe
what they use the gorgonian for most between feeding,
protection, and reproduction.
Chiappone et al. (2003) found C. gibbosum in pairs
the majority of the time; the results from this study were
not consistent with this conclusion. Of the four pairs of
snails observed in this study, all but one exhibited signifi-
cant association (A1,2 > 0.5); the average association varia-
ble also showed overall significant association between
snail pairs. Lasker and Coffroth (1988) collected associa-
tion data at 3 sites in the San Blas Islands, Panama; two of
the three sites showed significant association of C. gibbo-
sum individuals, a conclusion consistent with this study. A
possible reason for this association could be mating. It is
possible that snails 11 and 12 could be a male and female
pair who had just laid their egg case.
This study served to increase knowledge of the densi-
ty of flamingo tongue snails and gorgonians in Discovery
Bay, Jamaica. By combining the data from this study with
that of Snyder (2013), future researchers will have a more
comprehensive understanding of gorgonian and C. gibbo-
sum populations of west forereef area.
ACKNOWLEDGMENTS
I would like to thank E Burge for selecting me to partic-
ipate in MSCI 477/499 Jamaica Maymester course as well
as all the guidance he gave me on my project. I would also
like to thank S Luff, D Scarlet, and Snow for all their help
with the diving portion of my project from driving to the
boat to marking my sites. Thank you to C O’Shea for being
a supportive dive buddy and helping me to collect my data.
Finally, thank you to Coastal Carolina University and the
Discovery Bay Marine Laboratory for their support in un-
dergraduate research efforts and allowing me to use their
facilities and equipment.
LITERATURE CITED
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among grazers: Variability in the distribution of the gastro-
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the gorgonian coral, Leptogorgia. Biol Bull. 151: 344-356.
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GORDON: FLAMINGO TONGUE RESIDENCE TIME18
29. TUBE AND VASE SPONGE DIVERSITY, ABUNDANCE, AND DENSITY OF
THEIR SYMBIONT, OPHIOTHRIX SUENSONII
Tiffany M. Beheler
Department of Marine Science, Coastal Carolina University, PO Box 261954, Conway, SC 29526
ABSTRACT
Discovery Bay, Jamaica has a fringing reef which is an ideal habitat for Porifera. Sponges are the simplest multicellu-
lar organisms, as well as the most prominent, abundant, and diverse component in a Caribbean sub-rubble reef community
(Diaz and Rutzler 2001). They are a foundation species within the reef and have an important symbiotic relationship with
the brittle star Ophiothrix suensonii. The sponges in Discovery Bay are crucial to the reef and the brittle stars. They pro-
vide housing and the brittle star helps the sponge by cleaning the surface. The relationship between O. suesonii and marine
sponges benefits the health and diversity of coral reefs. During the month of May 2014, 125 sponges were surveyed at the
Discovery Bay Marine Laboratory. Of the 125 sponges surveyed, 43 brittle stars were observed. Niphates digitalis housed
30.23% of brittle stars. Past studies by Henkel and Pawlik (2005) have found that O. suensonii and N. digitalis are associat-
ed with each other. Brittle stars did not vary between site and sponge species. However, the average sponge surface area
differed intraspecifically. Xestospongia muta had the largest average surface area.
KEYWORDS: symbiotic relationship, brittle stars, density, surface area, Discovery Bay
This research was conducted as part of Coastal Carolina Universi-
ty’s classes MSCI 477, Ecology of Coral Reefs, and MSCI 499,
Directed Undergraduate Research in Discovery Bay, Jamaica, 14
–31 May 2014. Contact e-mail: tmbehele@coastal.edu
INTRODUCTION
DISCOVERY BAY, JAMAICA is home to a fringing reef
that is continuous across the mouth of the lagoon vir-
tually cutting the bay off from the sea (Gayle and Woodley
1998). The reefs found here are home to numerous phyla,
Porifera being one of them. Marine sponges thrive on coral
rubble and are very common in Discovery Bay because the
reef is composed mainly of skeletons of Acropora palmata
(Lamarck, 1816) and Millepora complanata (Lamarck,
1816) (Gayle and Woodley 1998). However, the sponge
population has not always been diverse and abundant. In
1980, Hurricane Allen struck the north coast of Discovery
Bay, negatively impacting the reefs and thus, the marine
sponges (Wilkinson and Cheshire 1988). Prior to the hurri-
cane the reef contained dense thickets of Acropora cervi-
cornis (Lamarck, 1816), and some were destroyed which
buried multiple species of sessile invertebrates (Wilkinson
and Cheshire 1988). In 1983, the sponge population was
again depleted due to an epidemic of Diadema antillarum
(Lamarck, 1814) (Gayle and Woodley 1998). This reduc-
tion led to an increase in non-crustose algae, prohibiting the
success of sponges. The sponge population has bounced
back since the decline in 1980, and has had a positive influ-
ence on the reef.
Sponges are the simplest multicellular marine organ-
isms. These sessile invertebrates are prominent on the reef
at various depths. Sponges, in some instances, have been
known to have higher species composition and diversity
compared to coral and algae. Sponges are an important
functional and structural component of coral reefs because
they provide refuge to a wide range of infauna (Henkel and
Pawlik 2005). A recent publication suggested sponges com-
prise 60% of all the sessile cryptic species making them a
crucial part of coral reefs in Curaçao and Bonaire (Diaz and
Rutzler 2001).
Even though many species seek out sponges for ref-
uge; sponges still have predators of their own. Sponges
avoid predation through physical and chemical deterrents
such as spicules which can work in conjunction with chem-
ical deterrents (Wulff 2006). These defenses make sponges
a prime habitat refuge for many different species. Different
species of small, secondary sponges, crustaceans, cnidari-
ans, echinoderms, molluscs, polychaetes, and bryozoans
have all exhibited some association with sponges (Wulff
2006). Diaz and Rutzler found 192 species of crustaceans,
ophiuroids, mollusks, and fishes inhabiting the reef spong-
es, Aplysina lacunosa (Pallas, 1766) and Aplysina archeri.
Being able to provide refuge to a large abundance of spe-
cies ensures diversity among the reef. Their association
with other organisms, by providing refuge, is one of the
characteristics that make sponges a crucial component of
coral reefs (Bell 2008).
There are several theories as to why brittle stars seek
out sponges as a preferred habitat, one of which is for pro-
tection. Brittle stars have predators from a range of phyla
but most of their predators are other echinoderms, crusta-
ceans, and fish (Warner 1971). Warner (1971) found that
39% of fish and crustaceans from the British Isles had the
brittle star Ophiothrix fragilis (Abildgard, 1789) in their
KORALLION. VOL 5. 2014 19
