Coral parasites and predators

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Transcript Coral parasites and predators

What are the most widespread coral
parasites and localized predators,
and what impact do they have on
coral reefs?
Rachael L. Shearouse
background
• Parasitism: a type of symbiotic relationship
between two organisms in which one
species lives on or in another, drawing
nourishment from that species at its
expense
• Localized predator: a predator who only
feeds on prey within a certain area
Most widespread Parasites and
Localized Predators
• Parasitic Bivalves:
Lithophaga
L. simplex
Fungiacava
• Localized Predators:
Coralliophila
C. violacea
C. abbreviata
Hermodice carunculata
Lithophaga simplex
• Inhabits the scleractinian
coral, Astreopora
myriophtholma, in high
density
• Consumes large amounts
of coral, leaving hollow
coral skeletons
• May have a slight
mutualistic relationship
(Mokady 1998)
Lithophaga and Fungiacava
• Both geneses have restricted feeding to live corals
• Each species displays host-specificity preventing
competition for the same host
• Increases reef destruction
• Causes bioerosion
Coralliophila violacea
• Outbreaks of 2 to 100’s of snails on
a single coral
• Leave white “scars” which serve as
entrances for boring organisms
• Weaken entire reef
• Localized tissue damage on
margins and interior of reef
• Cause large surface injuries in the
interior of the colony
• Cause the development of new
energy sinks in the interior of the
reef
• Feed on coral by sucking with
proboscis
(Oren 1998)
Coralliophila abbreviata
• The coral Acropora palmata
is declining with little signs
of recovery in the Caribbean
• Lack of survival is due
largely to predation by C.
abbreviata
• C. abbreviata causes coral
colonies to become remnant
colonies
• C. abbreviata has the
potential to inhibit the
recover of A. palmata
populations
(Grober-Dunsmore 2006)
Hermodice carunculata
• Vibrio shiloi is the causative
agent of bleaching in the coral
Oculina patagonica
• V. shiloi can not live on coral in
temperatures lower then 20 ۫C
• H. carunculata acts as a winter
reservoir
• V. shiloi reproduces inside H.
carunculata
• When temperatures rise V. shiloi
causes mass bleaching events
(Sussman 2003)
Hermodice carunculata
• Fireworm predation causes
permanent damage to
milleporid hydrocorals
• The open space created by
fireworms is then colonized
by algae
• 97% of the bare space
caused by fireworm feeding
was colonized by algae a
month later
• Consumption of M. complanta
by H. carunculata sufficiently
limits coral growth and
recovery
(Witman 1988)
Overall Impacts
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Localized coral tissue damage
Large rates of coral consumption
Bioerosion: breakdown of coral reef structure
Cause secondary mortality after hurricanes
and other tropical storms
• Spread coral diseases
Possible Solutions
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Restore coral reef trophic levels
Reintroduce predators that feed on these coral parasites
and localized coral predators
Reduce over fishing to bring back natural predators
Marine Protected Areas
Works Cited
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Grober-Dunsmore, R., Bonito, V., and Frazer, TK. 2006. Potential inhibitors to
recovery of Acropora palmata populations in St. John, US Virgin Islands. Marine
Ecology-Progress Series 321:123-132
Johnston, L. and Miller, MW. 2007. Variation in life-history traits of the corallivorous
gastropod Coralliophila abbreviata on three coral hosts. Marine Biology 150:12151225.
Kleemann, Karl. 1995. Associations of coral and boring bivalves: Lizard Island (Great
Barrier Reef, Australia) versus Safaga (North Red Sea). Beitraege zur Palaeontologie
20:31-39.
Kleemann, KH. 1980. Boring bivalves and their host corals from the Great Barrier
Reef. Journal of Molluscan Studies 46:13-54.
Mokady, O., Y. Loya and B. Lazar. 1998. Ammonium contribution from boring bivalves
to their coral host- a mutualistic symbiosis? Marine Ecology Progress Series 169:295301.
Nybakken, James W. and Mark D. Bertness. Marine Biology: An Ecological Approach
Sixth Edition. Pearson Benjamin Cummings, Inc. San Francisco, CA. 2005. 407-453.
Oren, U., Brickner and Y. Loya. 1998. Prudent sessile feeding by the corallivore snail
Coralliophila violacea on coral energy sinks. Proc. R. Soc. Lond. B 265:2043-2050.
Sussman, M., Loya, Y., Fine, M., and Rosenberg, E. 2003. The marine fireworm
Hermodice carunculata is a winter reservoir and spring-summer vector for the coral
bleaching pathogen Vibrio shiloi. Environmental Microbiology 5: 250-255.
Witman, JD. 1988. Effects of predation by the fireworm Hermodice carunculata on
milleporid hydrocorals. Bulletin of Marine Science 42:446-458.