an energy cost – energy that cannot be used for growth,
reproduction, resistance to diseases, or wound repair
(Cortés and Risk, 1985; Rogers, 1990; Fabricius, 2005).
In the ETP, the impact of sediments have been studied
in Mexico (Ochoa-López et al., 1998; Granja-Fernández
and López-Pérez, 2008), Costa Rica (Cortés, 1990;
Alvarado et al., 2009), Colombia (Zapata and VargasÁngel, 2003), and Ecuador mainland (Glynn, 2003). In
some areas, for example, Golfo Dulce in southern Costa
Rica, terrigenous sedimentation resulted in the cessation
of reef growth (Cortés et al., 1994).
Organism extraction
The impact of reef organisms extraction has not been studied in detail. In several countries in the region ornamental
fishes are extracted for the aquarium trade with no or very
limited control (McCauley et al., 2008; http://www.
aquariumcouncil.org). Corals and octocorals are also
extracted for the curio trade in El Salvador (personal
observation), Costa Rica (Cortés and Murillo, 1985),
Colombia (Zapata and Vargas-Ángel, 2003), and Ecuador
(Glynn, 2003). Panama is the only country in the region
with laws that prohibit the extraction of live or dead
coral (Maté, 2003), as is also in the Galápagos Islands
(J. S. Feingold, personal communication).
Climate change
Climate change is now considered one of the main threats
to coral reefs worldwide (Hughes et al., 2003; HoeghGuldberg et al., 2007; Hughes et al., 2007; Baker et al.,
2008). Sea water warming and associated bleaching is
the most obvious impact on corals reefs, resulting in reduction in growth rates, reproductive output, recruitment/
survivorship of larvae, competitive abilities, capacity to
regenerate tissue, increased susceptibility to diseases/stress,
and partial/total mortality of the colony. There can also be
changes in the structure and functioning of coral
populations and reef communities, and phase shifts to
different group/species community composition (Baker
et al., 2008; McClanahan et al., 2008). A not so obvious
consequence of the accumulation of CO 2 in the atmosphere
is ocean acidification (Kleypas et al., 2006; HoeghGuldberg et al., 2007), and this may be the main threat to
the existence of coral reefs in the future. This problem is
especially exacerbated in the ETP, since pH in the region
is lower than other oceans, and drops even more during
the upwelling periods.
Coral reef resilience
Resilience is generally defined as the ability of a coral reef
to return to a previous state after some perturbation (West
and Salm, 2003; Nyström et al., 2008). Several characteristics of coral reefs are recognized as important to maximized resilience: these include maintaining a healthy
herbivore community, high biodiversity, inter-reef and
inter-system connectivity, and reduced human impact
(Hughes et al., 2005; Mumby and Hastings, 2008;
Nyström et al., 2008). Speed of recovery and resilience
of coral reefs is greater in areas with less human activity.
Conclusions
ETP coral reefs are constructed by just a few species
of reef-building corals, yet they are highly complex in
interspecies interactions (Cortés, 1997; Glynn, 2004).
As carbonate structures, they started growing shortly
after rising sea level flooded appropriate substrates over
5,000 years ago, but the frameworks are fragile, with little
cementation, and are easily bioeroded. For this reason,
there are practically no examples of exposed Holocene
fossil reefs in the region as is so common on the Caribbean. These coral reefs are widely distributed from southern Baja California to Ecuador, including offshore islands,
with a similar suite of reef-building corals (Pocillopora
spp., Porites lobata and Pavona spp.), even though they
range from extreme dry regions to very humid and from
upwelling to nonupwelling areas. The main impact on
ETP coral reefs have been El Niño warming events; other
disturbances include cooling events, subaerial exposure,
excessive terrigenous sedimentation, organisms extraction, and climate change, among others. The corals in this
region were significantly impacted by the 1982/83 El
Niño and then again by the 1997/98 event, but most reefs
are recovering, though slowly. Coral reef resilience must
be maximized by maintaining a healthy herbivore community, high biodiversity, inter-reef and inter-systems connectivity, and reduced human impact.
Bibliography
Alfaro, E. J., 2002. Some characteristics of the annual precipitation cycle in Central America and their relationships with its
surrounding tropical oceans. Tópicos en Meteorología y
Oceanografía, 9, 88–103.
Alfaro, E. J., 2008. Ciclo diario y anual de variables troposféricas
y oceánicas en la Isla del Coco. Revista de Biología Tropical,
56(Suppl. 2), 19–29.
Alfaro, E. J., and Lizano, O. G., 2001. Algunas relaciones entre las
zonas de surgencia del Pacífico Centroamericano y los océanos
Pacífico y Atlántico tropicales. Revista de Biología Tropical,
49(Suppl. 2), 185–193.
Alvarado, J. J., Fernández, C., and Cortés, J., 2009. Water quality
conditions on coral reefs at the Marino Ballena National Park,
Pacific Costa Rica. Bulletin of Marine Science, 84, 137–152.
Amador, J. A., Alfaro, E. J., Lizano, O. G., and Magaña, V. O.,
2006. Atmospheric forcing of the eastern tropical Pacific:
a review. Progress in Oceanography, 69, 101–142.
Badan-Dangon, A., 1998. Coastal circulation from the Galápagos to
the Gulf of California. In Robinson, A. R., and Brink, K. H.
(eds.), The Sea. New York: John Wiley, pp. 315–343.
Baker, A. C., Glynn, P. W., and Riegl, B., 2008. Climate change and
coral reef bleaching: an ecological assessment of long-term
impacts, recovery trends and future outlook. Estuarine, Coastal
and Shelf Science, 80, 435–471.
Bezy, M. B., Jiménez, C., Cortés, J., Segura, A., León, A., Alvarado,
J. J., Gillén, C., and Mejía, E., 2006. Contrasting Psammocoradominated coral communities in Costa Rica, tropical eastern
Pacific. In Proceedings of the 10th International Coral Reef
Symposium, Okinawa, pp. 376–381.
EASTERN TROPICAL PACIFIC CORAL REEFS
355
reproduction, resistance to diseases, or wound repair
(Cortés and Risk, 1985; Rogers, 1990; Fabricius, 2005).
In the ETP, the impact of sediments have been studied
in Mexico (Ochoa-López et al., 1998; Granja-Fernández
and López-Pérez, 2008), Costa Rica (Cortés, 1990;
Alvarado et al., 2009), Colombia (Zapata and VargasÁngel, 2003), and Ecuador mainland (Glynn, 2003). In
some areas, for example, Golfo Dulce in southern Costa
Rica, terrigenous sedimentation resulted in the cessation
of reef growth (Cortés et al., 1994).
Organism extraction
The impact of reef organisms extraction has not been studied in detail. In several countries in the region ornamental
fishes are extracted for the aquarium trade with no or very
limited control (McCauley et al., 2008; http://www.
aquariumcouncil.org). Corals and octocorals are also
extracted for the curio trade in El Salvador (personal
observation), Costa Rica (Cortés and Murillo, 1985),
Colombia (Zapata and Vargas-Ángel, 2003), and Ecuador
(Glynn, 2003). Panama is the only country in the region
with laws that prohibit the extraction of live or dead
coral (Maté, 2003), as is also in the Galápagos Islands
(J. S. Feingold, personal communication).
Climate change
Climate change is now considered one of the main threats
to coral reefs worldwide (Hughes et al., 2003; HoeghGuldberg et al., 2007; Hughes et al., 2007; Baker et al.,
2008). Sea water warming and associated bleaching is
the most obvious impact on corals reefs, resulting in reduction in growth rates, reproductive output, recruitment/
survivorship of larvae, competitive abilities, capacity to
regenerate tissue, increased susceptibility to diseases/stress,
and partial/total mortality of the colony. There can also be
changes in the structure and functioning of coral
populations and reef communities, and phase shifts to
different group/species community composition (Baker
et al., 2008; McClanahan et al., 2008). A not so obvious
consequence of the accumulation of CO 2 in the atmosphere
is ocean acidification (Kleypas et al., 2006; HoeghGuldberg et al., 2007), and this may be the main threat to
the existence of coral reefs in the future. This problem is
especially exacerbated in the ETP, since pH in the region
is lower than other oceans, and drops even more during
the upwelling periods.
Coral reef resilience
Resilience is generally defined as the ability of a coral reef
to return to a previous state after some perturbation (West
and Salm, 2003; Nyström et al., 2008). Several characteristics of coral reefs are recognized as important to maximized resilience: these include maintaining a healthy
herbivore community, high biodiversity, inter-reef and
inter-system connectivity, and reduced human impact
(Hughes et al., 2005; Mumby and Hastings, 2008;
Nyström et al., 2008). Speed of recovery and resilience
of coral reefs is greater in areas with less human activity.
Conclusions
ETP coral reefs are constructed by just a few species
of reef-building corals, yet they are highly complex in
interspecies interactions (Cortés, 1997; Glynn, 2004).
As carbonate structures, they started growing shortly
after rising sea level flooded appropriate substrates over
5,000 years ago, but the frameworks are fragile, with little
cementation, and are easily bioeroded. For this reason,
there are practically no examples of exposed Holocene
fossil reefs in the region as is so common on the Caribbean. These coral reefs are widely distributed from southern Baja California to Ecuador, including offshore islands,
with a similar suite of reef-building corals (Pocillopora
spp., Porites lobata and Pavona spp.), even though they
range from extreme dry regions to very humid and from
upwelling to nonupwelling areas. The main impact on
ETP coral reefs have been El Niño warming events; other
disturbances include cooling events, subaerial exposure,
excessive terrigenous sedimentation, organisms extraction, and climate change, among others. The corals in this
region were significantly impacted by the 1982/83 El
Niño and then again by the 1997/98 event, but most reefs
are recovering, though slowly. Coral reef resilience must
be maximized by maintaining a healthy herbivore community, high biodiversity, inter-reef and inter-systems connectivity, and reduced human impact.
Bibliography
Alfaro, E. J., 2002. Some characteristics of the annual precipitation cycle in Central America and their relationships with its
surrounding tropical oceans. Tópicos en Meteorología y
Oceanografía, 9, 88–103.
Alfaro, E. J., 2008. Ciclo diario y anual de variables troposféricas
y oceánicas en la Isla del Coco. Revista de Biología Tropical,
56(Suppl. 2), 19–29.
Alfaro, E. J., and Lizano, O. G., 2001. Algunas relaciones entre las
zonas de surgencia del Pacífico Centroamericano y los océanos
Pacífico y Atlántico tropicales. Revista de Biología Tropical,
49(Suppl. 2), 185–193.
Alvarado, J. J., Fernández, C., and Cortés, J., 2009. Water quality
conditions on coral reefs at the Marino Ballena National Park,
Pacific Costa Rica. Bulletin of Marine Science, 84, 137–152.
Amador, J. A., Alfaro, E. J., Lizano, O. G., and Magaña, V. O.,
2006. Atmospheric forcing of the eastern tropical Pacific:
a review. Progress in Oceanography, 69, 101–142.
Badan-Dangon, A., 1998. Coastal circulation from the Galápagos to
the Gulf of California. In Robinson, A. R., and Brink, K. H.
(eds.), The Sea. New York: John Wiley, pp. 315–343.
Baker, A. C., Glynn, P. W., and Riegl, B., 2008. Climate change and
coral reef bleaching: an ecological assessment of long-term
impacts, recovery trends and future outlook. Estuarine, Coastal
and Shelf Science, 80, 435–471.
Bezy, M. B., Jiménez, C., Cortés, J., Segura, A., León, A., Alvarado,
J. J., Gillén, C., and Mejía, E., 2006. Contrasting Psammocoradominated coral communities in Costa Rica, tropical eastern
Pacific. In Proceedings of the 10th International Coral Reef
Symposium, Okinawa, pp. 376–381.
EASTERN TROPICAL PACIFIC CORAL REEFS
355