Underwater CArds for Assessing Coral Health on Caribbean Reefs

Abstract

Coral reefs are under increasing stress globally from a number of
causes, including climate warming, poor water quality and over fishing.
Disease outbreaks not only result in coral loss, but they also cause
significant changes in community structure, species diversity and reefassociated
organisms.
Coral diseases in the Caribbean have become a major player in the
progressive decline of these important communities. They impact both
well-managed and unmanaged reefs. However, strategies for dealing with
disease outbreaks are currently non-existent. The increasing frequency
with which diseases influence and alter reef communities means they
must be considered and incorporated into management plansof Caribbean corals and other reef organisms. The decision tree
is color coded to assist with navigation through the cards. After
reviewing all disease descriptions and images to gain an overview of
the range of signs of disease and compromised health, the following
steps will enable you to assess the health status of a coral, sponge,
octocoral, etc. Note that a variety of factors other than disease
(e.g. predation, grazing, anchors) cause lesions.

Full text

Underwater Cards for Assessing Coral Health on
Caribbean Reefs
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Underwater Cards for
Assessing Coral Health on Caribbean Reefs
Ernesto Weil1, Anthony J. Hooten2.
Coral Disease
Coral reefs are under increasing stress globally from a number of
causes, including climate warming, poor water quality and over fishing.
Disease outbreaks not only result in coral loss, but they also cause
significant changes in community structure, species diversity and reef-
associated organisms.
Coral diseases in the Caribbean have become a major player in the
progressive decline of these important communities. They impact both
well-managed and unmanaged reefs. However, strategies for dealing with
disease outbreaks are currently non-existent. The increasing frequency
with which diseases influence and alter reef communities means they
must be considered and incorporated into management plans.
The CRTR Disease Working Group
The CRTR Disease Working Group has been funded by the Coral Reef
Targeted Research & Capacity Building for Management Program (CRTR)
to advance understanding of coral disease in a number of key areas.
In particular, the CRTR Disease Working Group’s research is providing a
greater understanding of the ways in which coral diseases can alter reef
function and the conditions under which outbreaks may occur.
Documenting abundance and prevalence of disease and monitoring
changes in disease through time are key steps in understanding how
factors like ocean warming and deteriorating water quality may affect
disease dynamics.
To assist with our objectives, the CRTR Disease Working Group has
produced these Underwater Cards for Assessing Coral Health on
Caribbean Reefs so that recreational, professional and scientific divers
can all assist with gathering information on the occurrence of coral
reef diseases.
By using these cards, you can:
• Learn to identify diseases in Caribbean coral and other
reef organisms and survey techniques for measuring
coral disease prevalence;
• Gather information on the distribution and abundance of
coral diseases on local reefs;
• Monitor the health of local coral reefs and identify potential
drivers of disease abundance;
• Contribute to a world-wide data base on coral disease;
• Help to conserve the world’s coral reefs.
How to use these cards
These cards start with a decision tree for assessing the health status
of Caribbean corals and other reef organisms. The decision tree
is color coded to assist with navigation through the cards. After
reviewing all disease descriptions and images to gain an overview of
the range of signs of disease and compromised health, the following
steps will enable you to assess the health status of a coral, sponge,
octocoral, etc. Note that a variety of factors other than disease
(e.g. predation, grazing, anchors) cause lesions.
1. Decide if a coral shows signs of tissue loss (red section), tissue
discoloration (blue section), anomalous growth (green section)
or some other sign of compromised health (yellow section).
2. At each level in the key for the colored section selected,
decide which category best describes the signs observed.
3. Go to the appropriate colored section in this card set to
check disease images and descriptions.
4. Record your observations on the data sheet provided
at the end of this card set.
1 Department of Marine Sciences, University of Puerto Rico. 2
US Coordinator Global Coral Reef Targeted Research Program and AJH, Environmental Services.
The CRTR Program is a partnership between the Global Environment
Facility, the World Bank, The University of Queensland (Australia),
the United States National Oceanic and Atmospheric Administration
(NOAA) and approximately 50 research institutes and other third-parties
around the world.
CRTR Program Project Executing Agency, Centre for Marnie Studies, Gerhmann Building, The University of Queensland, St Lucia, QLD 4072, Australia
Telephone: +61 7 3346 9942 Facsimile: +61 7 3346 9987 Email: info@gefcoral.org Internet: www.gefcoral.org
How to use these cards

Caribbean Coral Health – Decision Tree
Tissue Loss – Predation
1. Fish Predation (FPR)
2. Invertebrate Predation (IPR)
Tissue Loss – Non-Predation – Colored Band Diseases
3. Black Band Disease (BBD)
4. Caribbean Ciliate Infection (CCI)
5. Aspergillosis (ASP)
6. Purple Spots (PS)
7. Red Band Disease (RBD)
Tissue Loss – Caribbean White Syndromes
8. White Band Disease (WBD)
9. White Plague (WP)
10. White Patch Disease (WPA)
11. Caribbean White Syndromes (CWS)
Tissue Discoloration – White
12. Bleaching (BL)
Tissue Discoloration – Non White
13. Dark Spots Disease (DSD)
14. Caribbean Yellow Band Disease (CYBD)
Growth Anomalies
15. Growth Anomalies (GAN)
Compromised Health
16. Compromised Health in Hard Corals (CHC)
17. Compromised Health in Octocorals (CHO)
18. Competition – Overgrowth (CO)
Diseases in Other Reef Organisms
19. Coralline White Band Syndrome (CWBS)
20. Other Reef Organisms – Sponges
21. Other Reef Organisms – Zoanthids & Hydrocorals
Caribbean – Decision Tree
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Tissue Loss – Predation
Fish Predation (FPR)
• Few organisms feed exclusively on
coral tissues. Common large predators
include parrotfish, surgeonfish and
urchins. Small predators include butterfly
-fish, damselfish, snails and fireworms.
Commonly confused with:
• White band disease, white plague
disease, white syndromes, bleaching
and other white scars.
Key ID characteristics:
• Fish and urchin feeding leave irregular
scars with broken skeleton. Parrotfish
bites are usually large and focused
along ridges or edges, or at the center
of colonies.
• Damselfish create their feeding gardens
biting and killing coral tissue so algae
can grow. Areas are usually round and
not larger than 50cm in diameter.
Fish defends territory aggressively.
• Common coral genera affected
include Montastraea,
Diploria,
Colpophyllia,
Acropora,
Stephanocoenia,
etc.
Parrotfish
Parrotfish
Damselfish
Damselfish
DamselfishDamselfishParrotfishParrotfish
1

Invertebrate
Predation (IPR)
• Snails (Coralliophilia) and fireworms
(Hermodice) are most common
invertebrate predators in Caribbean.
• Sea urchins accidentally feed on coral
while grazing nearby. Surveyors must
carefully look around areas of recent
coral tissue mortality and try to find
potential predators.
Commonly confused with:
• White band disease, white plague
disease, white syndromes, bleaching
and other white scars.
Key ID characteristics:
• Snail and fireworm scars show irregular
edges devoid of tissue and no apparent
skeletal damage. Area affected usually
small with turf algal growth preceding
recently denuded area. Edge may show
strings of tissue or mucus. Not too many
colonies affected, unless high densities
of predators present.
Common coral
affected include
Montastraea,
Acropora, Diploria
and Colpophyllia.
Coralliophilia
Coralliophilia
Hermodice
Hermodice
Hermodice
Coralliophilia
Coralliophilia
Tissue Loss – Predation
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Tissue Loss – Non-Predation
Colored Band Diseases
Black Band Disease (BBD)
• Discrete dark band or fuzzy, filamentous
bacterial mat dominated by cyanobacteria
at interface of live tissue and bare skeleton,
sometimes overlapping live tissue.
• Band color can vary from black to
reddish-brown.
Pathogen(s): P. coralliticum, Disulfovibrio sp.
and Beggiatoa sp. and other bacteria.
Distribution: Wider Caribbean (1-25m).
Host range: 19 coral and 6 octocoral species
(Montastraea, Diploria,
Siderastrea, Colpophyllia,
Pseudoplexaura, Gorgonia, etc).
Commonly confused with:
• Caribbean ciliate infections, dark spots
disease, dark bands, etc.
Key ID characteristics:
• Macroscopically, the fuzzy, black and
white peppered, thread-like filamentous
bacterial mat, the clean bare skeleton,
and the distant, secondary algal growth.
• Microscopically, the thread like,
filamentous cyanobacteria.
Rate of advance: Variable (1.5-40cm/mth).
Impact: Partial to total colony mortality.
Seasonality: Summer-Fall months.
Detail
Detail
3

Tissue Loss – Non-Predation
Colored Band Diseases
Caribbean Ciliate
Infection (CCI)
• Dark, mostly spotted, scattered or dense
band formed of ciliates that could lag
behind disease (WPD or CYBD) edge or
be intermingled with live tissue.
Pathogen(s): Foliculinid ciliates
(Halofoliculina sp.).
Distribution: Wider Caribbean (1-20m).
Host range: 22 coral species (Montastraea,
Diploria, Agaricia, Acropora, Dichocoenia,
etc) and Millepora.
Commonly confused with:
• Black band disease, dark bands.
Key ID characteristics:
• Appearance might vary, from few, dark spots
to a discrete, black band of varying width.
• When looked at closely, the tiny, individual
dark ciliates can be seen.
Rate of advance: Unknown but
generally slow.
Impact: Slowly kills tissues and colonies
over time.
Seasonality: None.
Detail
DetailDetail
4
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Colored Band Diseases
Aspergillosis (ASP)
• An octocoral disease, most commonly
found on sea fans (Gorgonia ventalina).
Purple or colored areas (host reaction)
around dead tissue and exposed
endoskeleton.
Pathogen: the fungus Aspergillus sydowii.
Other species of this genus might
be involved.
Distribution: Wider Caribbean (0-30m).
Host range: 10 octocoral species (Gorgonia,
Pseudoterogorgia, Plexaura, Plexaurella).
Commonly confused with:
• Other purple pigmentation responses
produced by predation, competition,
mechanical injuries, other pathogens.
Key ID characteristics:
• The purple bands/areas on the sea fan
blade around the infected areas.
Coloration is a host response.
• With magnifying lens, fungal hyphae
(filaments) might be seen in infected
tissues.
Rate of advance: Usually slow,
0.5cm/mth.
Prevalence: Variable (0.1%-30%).
Seasonality: All year.
Impact: From partial tissue loss to total
colony mortality over time.
Detail
Detail
Tissue Loss – Non-Predation
5

Colored Band Diseases
Purple Spots (PS)
• Infections appear as small purple dots
of similar size all over the colony. Purple
areas produced by the host response to
the pathogens.
Pathogen(s): Protozoan (unknown
Labyrinthulomycote). Small hydrozoan
produce similar spots.
Distribution: Caribbean, few reports
from Florida, Mexico and Puerto Rico
(3-20m).
Host range: The sea fan Gorgonia
ventalina and other octocorals.
Commonly confused with:
• Aspergillosis or other
pigmentation responses.
Key ID characteristics:
• Typically small uniform purple dots
spread over the blade of the sea fan.
Prevalence: Low, no data available.
Seasonality: Unknown.
Impact: No apparent mortality of
significant areas.
Detail
Tissue Loss – Non-Predation
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Detail
Detail
Tissue Loss – Non-Predation
Colored Band Diseases
Red Band Disease (RBD)
• Red/maroon band of mostly cyanobacteria
that kills tissue leaving bare skeletal areas
in both octocorals and hard corals.
Pathogen(s): Cyanobacteria (Oscillatoria
spp.), sometimes Schizothrix spp.
Distribution: Wider Caribbean (4-20m).
Host range: 13 octocoral spp. (Gorgonia,
Plexaura, etc.), and few corals.
Commonly confused with:
• Black band disease.
Key ID characteristics:
• Red band looks fuzzy and filamentous
and is usually clear in seafans but not in
other octocorals or hard corals, where
it might be darker and more compact.
Rate of advance: Intermediate,
2-5cm/mth over G. ventalina.
Prevalence: Low.
Seasonality: Mostly during Summer
and Fall.
Impact: From partial tissue loss to
total colony mortality over time.
7

Tissue Loss – White Syndromes
White Band Disease
(WBD)
• Band of white, exposed skeleton or
bleached tissue separates healthy coral
tissue from algal colonized skeleton.
It can range from a few mm to several
cm wide.
Pathogen: Bacterium – Vibrio charchariae
and possibly other vibrios.
Distribution: Caribbean, Gulf of Mexico,
Florida and Bahamas (0-20m).
Host range: Acroporids (Acropora palmata,
A. cervicornis and the hybrid A. prolifera).
Commonly confused with:
• Bleaching, white plague, white pox,
other white syndromes and predation
by snails and fireworms.
Key ID characteristics:
• Wide band of clean skeleton separates
edge of tissue from algae colonized
skeleton. Sometimes tissue strings and
pieces sloughing off at the interface,
usually not observed in predation.
Rate of advance: Usually fast, 0.5-10cm/day.
Prevalence: Highly variable (<1%-30%).
Seasonality: Summer-Fall.
Impact: Partial and whole colony mortality.
8
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Tissue Loss – White Syndromes
White Plague (WP)
• Wide band of white, exposed skeleton
borders sharp edge of healthy coral tissue.
Gradient of algal colonized skeleton in
denuded skeleton.
Pathogen: Bacterium – Aurantimonas
coralicida.
Distribution: Wider Caribbean (1-30m).
Host range: 42 coral species and Millepora
complanata (Montastraea, Colpophyllia,
Diploria, Mycetophyllia, Dendrogyra,
Stephanochoenia, Siderastrea etc).
Commonly confused with:
• Bleaching, other white syndromes and
predation by snails, and fireworms.
Key ID characteristics:
• Fast advancing, wide white band starts
at interface with sediment at base of
colony, from depressions and crevices
over the colony, and from underneath
Halimeda algal mats in contact with live
tissue. Tissue “dissolves” fast, no strings
or pieces sloughing off infected area.
Sharp edge.
Rate of advance: Variable but fast
(1-10cm/day).
Prevalence: Variable (<1%-25%).
Impact: Second most damaging disease,
significant fast partial and colony mortality.
Seasonality: Outbreaks usually during
Summer-Fall.
Contagion
9

White Patch Disease (WPA)
• Also termed “white pox”, “acroporid
serriatosis” and “patchy necrosis”.
Irregular patches of tissue-free skeleton
on A. palmata colonies. Varying sizes.
Fast tissue resheeting may seal the lesion
shortly after the injury was produced.
Pathogen: Bacterium – Serratia marcenses
for white pox cases in Florida colonies.
Others Unknown.
Distribution: Gulf of Mexico, Florida,
Bahamas and Caribbean.
Host range: Acropora palmata.
Commonly confused with:
• Bleaching, white band disease, white
plague, other white syndromes, tissue
loss by apoptosis, and predation by
snails and damselfish.
Key ID characteristics:
• Irregularly shaped, white tissue-free areas
of different sizes over the colony with or
without tissue bits sloughing over the
injured area or at interface with live
tissue area.
Rate of advance: Fast (2.5-3cm/day).
Prevalence: Variable (<1%-15%)
during outbreaks.
Impact: High proportion of tissue loss during
outbreaks. Rarely kill the entire colony.
Seasonality: Summer-Fall with
short-time outbreaks.
Recovery
Tissue Loss – White Syndromes
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Tissue Loss – White Syndromes
Caribbean White
Syndromes (CWS)
• Diffuse patterns of tissue loss exposing
bands, patches or irregular shapes of bare
skeletal areas in contact with live tissue.
May appear anywhere on the colony.
• Coloration gradient indicating different
stages of algal colonization.
Pathogen(s): Unknown.
Distribution: Wider Caribbean (3-20m).
Commonly confused with:
• White plague, white band or tissue loss
by apoptosis, predation from snails
or fireworms.
Key ID characteristics:
• Irregular patterns of tissue loss or
whitening, focal origins in some cases.
Could affect any areas of the colony,
spreading from the focal origin.
Rate of advance: Variable.
Prevalence: Variable but generally low.
Impact: Low, with partial to total
colony mortality.
Seasonality: Summer-Fall with
short-time outbreaks.
Day 1
11

Tissue Discoloration – White
Bleaching (BL)
• Focal, multifocal-to-coalescing, or
irregular areas of tissue discoloration
due to the loss or reduction in the
number of endosymbiotic algae
(zooxanthellae) from coral tissue.
• The degree of bleaching can vary
from pale to white.
• Tissue is present, but with reduced
(pale) or absent pigmentation.
Cause: Associated with higher than
normal water temperatures, high UV,
high sedimentation and turbidity, cold
water snaps, etc.
Distribution: Wider Caribbean (1-45m).
Commonly confused with:
• White plague, white band or tissue
loss by apoptosis, white patch disease,
other white syndromes, and predation
from snails or fireworms.
Key ID characteristics:
• Tissue always present in discolored
(bleached) areas (compared with diseases).
• After some time, bleached tissue may
be associated with irregular patterns
of partial or whole colony tissue loss.
Prevalence: Variable and low
(background bleaching= <1%) to
high (80%) in warm water years.
Seasonality: Summer-Fall and could
extend through Winter-Spring.
Impact: Partial to total coral mortality
depending on intensity and duration. 12
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Tissue Discoloration – Non-White
Dark Spots Disease (DSD)
• Dark colored irregular or round spots,
patches or bands of variable sizes
where skeletal and tissue area could
be depressed.
Pathogen: Unknown.
Host range: 16 coral species, most common
in Siderastrea, Montastraea, Colpophyllia
and Stephanocoenia.
Distribution: Wider Caribbean (0-40m).
Seasonality: Variable but most common in
Summer-Fall.
Commonly confused with:
• Compromised health problems, other
dark responses.
Key ID characteristics:
• Tissue always present in darker areas.
These areas are usually depressed.
• Distribution over the colony is not regular
and number of spots/areas may vary
over time.
• Most common species affected include
S. siderea, M. faveolata and S. intersepta.
• S. intersepta is only affected in the
southern Caribbean.
Prevalence: Variable and low (<1%) except
on outbreaks (36%).
Seasonality: Summer-Fall but could extend
through Winter-Spring.
Impact: Usually limited partial mortality over
long periods of time.
13

Tissue Discoloration – Non-White
Caribbean Yellow Band
Disease (CYBD)
• Pale, yellow or white area that develops
into rings of 1-5cm wide bands that grow
outward killing coral tissue. Multiple focal
areas in same colony may coalesce.
Pathogen: Vibrio complex. May be a
disease of the zooxanthellae.
Host range: 11 coral species (Montastraea,
Colpophyllia, Diploria).
Distribution: Wider Caribbean (5-20m).
Commonly confused with:
• Bleaching, white plague, other white
syndromes and predation.
Key ID characteristics:
• Multifocal yellow/white tissue colored
spots, concentric rings, or bands at the
colony edges. May show color gradient
within band. Width of yellow band spatially
and seasonally variable (1-10cm).
• Montastraea is the most common genus
affected. Other species are rarely affected.
Rate of advance: Variable (0.5-4cm/mth).
Prevalence: highly variable (<1%-60%).
Seasonality: Summer-Fall but could extend
through Winter-Spring.
Impact: Partial to total colony mortality. Most
widespread and damaging coral disease.
Detail
14
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Growth Anomalies
(GAN)
• Tumor-like structures growing on surface of
coral/octocoral colonies that usually show
minor coloration changes or bleaching.
Calical structure may or may not change.
• Invertebrate galls are produced by
encroaching skeletal matrix around
individual endolithic or invertebrate
epibionts living in/on the coral skeleton
(polychaetes, sypunculids, fungi, crabs,
shrimp, algae, etc).
• Unexplained growth anomalies might
be caused by endolithic algae, fungi,
protozoans, virus or genetic mutations.
Host range: Several coral species
(Montastraea, Colpophyllia, Diploria,
Acropora) and octocoral spp. (Gorgonia,
Pseudoplexaura, Plexaura, Plexaurella).
Distribution: Wider Caribbean (2-25m).
Commonly confused with: N/A
Key ID characteristics:
• Fast growing areas on colony surface
with enlarged but otherwise not changed
skeletal structures (hyperplasias) or
uncharacteristic growth areas with
significant lost of calical and skeletal
structures (neoplasias).
• Coloration could vary or area might
be bleached.
Prevalence: Highly variable (<1%-12%
in some octocoral species).
Impact: Usually no mortality associated.
Growth Anomalies
15

Compomised Health
Compromised Health
in Hard Corals (CHC)
• Unhealthy looking tissues with clear signs
of recent mortality. Forms spots, bands,
rings and irregular areas of different sizes
and shapes.
Pathogen(s): Unknown.
Host range: 16 species of corals
(Montastraea, Siderastrea, Agaricia,
Diploria, Dendrogyra, Mycetophyllia).
Distribution: Wider Caribbean (2-25m).
Commonly confused with:
• Other disease problems such as white
syndromes, dark bands, dark spots,
Caribbean yellow band, etc.
Key ID characteristics:
• Unhealthy looking tissue usually at edge
or around rings of dead, algae-recolonized
areas over the colony. Some species show
pigmentation responses.
• Tissues usually sloughing off the skeletal
structure and sometimes a dark band
of bacteria might be found (similar to
atramentous necrosis in the IP).
Rate of advance: Unknown but low
and variable.
Prevalence: Low.
Seasonality: No apparent seasonality.
Impact: Partial to total colony mortality.
16
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Compromised Health
in Octocorals (CHO)
• Unhealthy looking tissues with clear signs
of recent mortality or “necrosis”. Forms
bands, focused or sparse spots or irregular
areas of different sizes.
Pathogen(s): Unknown, might be caused by
pathogens or environmental stress.
Host range: At least 6 species of octocorals.
Distribution: Wider Caribbean (2-20m).
Commonly confused with:
• Other disease problems in octocorals,
aspergillosis.
Key ID characteristics:
• Unhealthy looking tissue usually
showing signs of mortality and clean
bare endoskeleton is exposed. Polyps
retracted in affected areas and interphase
and healthy-looking area may show
pigmentation response. Tissues
might be sloughing off the branches.
Rate of advance: Unknown but low
and variable.
Prevalence: Low.
Seasonality: No apparent seasonality.
Impact: Partial to total colony mortality.
Detail
Detail
P. nutans P.porosa
E.caribaeorum
E.caribaeorum
Compomised Health
17

Competition
Overgrowth (CO)
• Direct (contact) competitive interactions
for substrate are common in sessile
reef invertebrates. Indirect (shadowing,
allelopathy, etc) and direct (aggression)
competition might produce physiological
stress and unhealthy tissue signs. Could
produce tissue mortality, pigmentation
responses and/or unhealthy looking tissues
in one or both competing species.
Distribution: Wider Caribbean (2-25m).
Commonly confused with:
• Could produce signs that might be
confused with other disease problems.
Key ID characteristics:
• Contact area between different species
or colonies of the same species show
stress signs manifested as discoloration
or pigmentation, tissue sloughing, tissue
mortality, etc. Many different interaction in
coral community, most common between
corals, between corals and sponges, corals
and zoanthids, corals and algae, corals and
cyanobacteria, etc. Very localized and not
spread out over the community. Sponges
and zoanthids might overgrowth and kill
coral tissue underneath.
Rate of advance: Unknown but low
and variable.
Prevalence: Variable.
Impact: Partial to total colony mortality.
Endolitic Sponge Endolitic Sponge
Cyanobacteria
Cyanobacteria
Filamentous Algae
Compomised Health
18
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Diseases in Other Reef Organisims
Coralline White Band
Syndrome (CWBS)
• A thin (0.2-0.5cm) white band slowly
advancing and leaving dead tissue areas
that are quickly recolonized by algae.
Rings may develop and coalesce
producing irregular patterns.
Pathogen(s): Unknown, sometimes
protozoans are associated with band, but
maybe as opportunistic, secondary parasites.
Host range: At least three different crustose
coralline algae affected (Neogoniolithon,
Lithophyllum, Titanoderma).
Distribution: Wider Caribbean (2-25m).
Commonly confused with:
• Only white band observed on CCA.
Key ID characteristics:
• White band is characteristically
conspicuous against the light purple
background of CCA.
Rate of advance: 0.2-0.7cm/mth.
Prevalence: Highly variable, low (<1%)
to high (>20%) during outbreaks.
Seasonality: No apparent seasonality.
Impact: Partial to total colony mortality. Kills
large numbers of coralline algae colonies
every year.
Detail
Trans-species contagion
CCA
S. siderea 19

Diseases in Other Reef Organisims
Other Reef
Organisms – Sponges
• Several species of sponges are showing
signs of disease throughout the Caribbean.
• Colonies show bands or areas of necrotic,
sloughing tissue and exposed protein/
spicule matrix.
Pathogen(s): Unknown.
Host range: Several species in different
genera (Xetospongia, Amphimedon,
Cliona, etc).
Distribution: Wider Caribbean (2-25m).
Commonly confused with: N/A
Key ID characteristics:
• Particular characteristics vary across
species. Cliona shows unhealthy looking
(“necrosis”) tissue that sloughs off, leaving
white, clean, exposed calcium carbonate.
Xetospongia shows unhealthy tissue
that disintegrates leaving internal matrix
exposed, and then it collapses.
• Other crustose sponges show yellow bands
or rings that spread out killing tissues.
Rate of advance: Not known but variable.
Some large X. muta colonies could
get killed in less than a month.
Prevalence: Highly variable, low (<1%)
to high (>20%) during outbreaks.
Seasonality: Mostly Summer-Fall.
Impact: Partial to total colony mortality.
X.muta
X.muta
Clionid Clionid 20
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Diseases in Other Reef Organisims
Other Reef Organisms –
Zoanthids & Hydrocorals
• Unhealthy looking tissues showing signs
of physiological stress (disease) with clear
signs of recent mortality. Form spots,
bands, rings and irregular areas of
different sizes.
Pathogen(s): Unknown – might be caused
by pathogens or environmental stress.
Host range: At least two species of
zoanthids Palythoa and two milleporids
(Millepora complanata).
Distribution: Wider Caribbean (2-20m).
Commonly confused with:
N/A
Key ID characteristics:
• Unhealthy looking tissue usually at edge
or center of colonies in both zoanthids
and hydrocorals.
• In Palythoa caribaeorum, white areas with
polyps retracted deeply and/or dissolution
of individual calices leaving plain, flat area.
• White, bleached or dead area on blades
of Millepora complananta are colonized
by algae CCA, which might indicate a
competition problem.
Rate of advance: Unknown but low
and variable.
Prevalence: Low.
Seasonality: No apparent seasonality.
Impact: Partial to total colony mortality.
Zoanthid
Hydrocoral
21

Underwater Cards –
Options for Recording & Reporting Observations of Coral Disease
Qualitative observations of coral disease
At the simplest level, it is useful to photograph and/or record
details of corals that are diseased or show signs of compromised
health. The following data could be recorded:
Date & Recorder:
Site/Habitat/Depth:
Disease/compromised health sign:
Growth form/Genus/species of coral:
Photo name(s) & number(s):
Additional observations (e.g. #corals/species affected):
Quantitative assessment of coral disease
Disease prevalence: The number of disease colonies and the
total number of healthy corals per unit area gives a measure of
disease prevalence. This is a better, but more time consuming way
of quantifying disease than estimating disease abundance.
1. Select an appropriate sampling unit (e.g. 10m x 2m
belt transect);
2. Select appropriate replication (e.g. 3-5 transects per depth
interval or habitat and three habitats per reef site and
3 reefs per zone);
3. Record all corals showing signs of disease or compromised
health and all healthy corals. Use formatted data sheets;
4. Calculate mean (± SE) percent of corals that are diseased
per habitat, reef and/or zone.
Disease abundance: A simpler way of recording the number
of cases of disease per unit area without recording all healthy
corals gives a measure of disease abundance. Same method as
prevalence but without recording all healthy colonies.
Disease incidence/recovery: Tagging and monitoring the
number of diseased corals in a given area through time identifies
the number of new cases of disease and the recovery colonies per
unit time. It provides a measure of disease incidence or spread
throughout the population and population recovery.
1. Select an appropriate area (e.g. 10m x 10m quadrat);
2. Select appropriate replication (e.g. 3 quadrats per habitat
or reef site);
3. Tag and map all diseased colonies within each quadrat;
4. Monitor quadrats regularly (e.g. weekly during outbreaks or
monthly), counting and tagging all new cases of disease and
checking old cases;
5. Calculate mean (± SE) # of new diseased and recovered
colonies per unit time.
Disease progression: Tagging and photographing corals through
time enables rates of disease progression across corals to be
calculated.
1. Tag several (>10) diseased colonies/species at study site;
2. Photograph each diseased coral with a scale bar and at a standard
angle - a tag or a nail could be used as a reference point;
3. Re-photograph tagged corals at regular intervals
(e.g. weekly or monthly);
4. Measure linear spread of disease front or progressive
area of tissue loss from images;
5. Calculate mean (± SE) rate of disease progression.
Many thanks to: Roger Beeden, Bette Willis, Laurie Raymundo, Drew Harvell, Thierry Work, Courtney Saltonstall Couch and Andy Bruckner for their input
and discussions during the production of these Cards. Thanks also to Esther Peters for the “neoplasia” photo and Andy Bruckner for the RBD Agoricia photo.
We thank the CRTR Program for its support and funding of this publication. Research leading to these Cards was funded by the CRTR Program, NOAA-CRES
(NA170p2919) and the Department of Marine Sciences, University of Puerto Rico.
Product code: CRTR 003/2008
© Coral Reef Targeted Research and Capacity Building for Management Program, 2008. Editorial design and production: Currie Communications, Melbourne, Australia, June 2008.
Recording & Reporting
spine

Genus Species Healthy Unknown COR FISH HER Other BBD CCI ASP PS RBD WBD WPD WPA WS
Acropora A.cervicornis
A.palmata
Montastraea M.faveolata
M.annularis
M.franksi
M.cavernosa
Siderastrea S.siderea
Stephanocoenia S.intersepta
Colpophyllia C.natans
Diploria D.strigosa
D.labyrinthiformis
Porites P. porites
P.astreoides
Undaria U.agaricites (all)
Agaricia A.lamarcki
Meandrina M.meandrites
Dendrogyra D.cylindrus
Mycetophyllia M.ferox
M.aliciae
Gorgonia G.ventalina
Erythropodium E.caribaeorum
Palythoa P.caribaeorum
Octocorals
CCA
Sponges
Other
GPS coordinates: Depth (m) Ave: m Depth (m) Max: m Temp ˚C
Tissue Loss
Predation
Colored Band Diseases
Name:
Date:
Reef:
Non-Predation (i.e. Disease)
Non-Distinct Bands

Name:
Date:
Reef:
Bleaching
Tissue Discoloration
Non-White Invert
Galls
Tremat-
odiasis
Compromised
Health
Competition
Other Reef
Organisms
Sponges
Growth
Anomalies
Genus Species % Focal Other DSD CYBD GAN Unex CHE CO CWBS Other Unk Other
Acropora A.cervicornis
A.palmata
Montastraea M.faveolata
M.annularis
M.franksi
M.cavernosa
Siderastrea S.siderea
Stephanocoenia S.intersepta
Colpophyllia C.natans
Diploria D.strigosa
D.labyrinthiformis
Porites P. porites
P.astreoides
Undaria U.agaricites (all)
Agaricia A.lamarcki
Meandrina M.meandrites
Dendrogyra D.cylindrus
Mycetophyllia M.ferox
M.aliciae
Gorgonia G.ventalina
Erythropodium E.caribaeorum
Palythoa P.caribaeorum
Octocorals
CCA
Sponges
Other
GPS coordinates: Depth (m) Ave: m Depth (m) Max: m Temp ˚C