non-carbonate substrates (Macintyre et al., 1992). The
relief of the reef structure is inherited from the noncarbonate substrate, with some large massive corals present. At Isla del Caño, the oldest framework was 2,000
year BP, while at Isla del Coco and the Galápagos Islands
samples from the base of the largest Porites colonies yield
dates of between 320 and 450 years BP (Macintyre et al.,
1992).
Postdepositional alteration of corals is minimal in the
ETP (Glynn and Macintyre, 1977; Cortés et al., 1994), as
is subsequent reef consolidation (Cortés, 1997; Manzello
et al., 2008). This may be due to the rapid accumulation
rates, lack of high turbulance, and, in general, low pH of
the surrounding waters (Glynn and Macintyre, 1977;
Cortés, 1997; Manzello et al., 2008). These reefs are subject to rapid bioerosion (Cortés, 1997; Fonseca et al.,
2006), resulting in very few examples of exposed Holocene reefs (Glynn and Wellington, 1983; Denyer and
Cortés, 2001). ETP reefs are very fragile and, in general,
are obliterated before preservation (Cortés, 1993). Branching corals are uncemented, and massive colonies are usually highly bioeroded and in many places unattached to
the substrate (Scott and Risk, 1988; Fonseca, 1999). Reef
framework is also bioeroded, especially once the coral dies
(Glynn et al., 1979; Glynn, 1988; Colgan, 1990; Glynn
and Colgan, 1992; Eakin, 1996; Reaka-Kudla et al.,
1996; Fonseca et al., 2006). In conclusion, reef preservation is very low in the ETP (Cortés, 1997).
Types of coral reefs
There are at least 35 species of zooxanthellate corals in
the ETP (Reyes-Bonilla, 2002), but only three are important reef builders across the entire region (Pocillopora
damicornis, P. elegans and Porites lobata). Pocillopora
spp. reefs are found in México (Reyes-Bonilla, 2003),
Costa Rica (Cortés, 1996/1997; Cortés and Jiménez,
2003), Panamá (Maté, 2003; Guzman et al., 2004, 2008),
Colombia (Glynn et al., 1982; Zapata and Vargas-Ángel,
2003), and the Galápagos Islands (Glynn and Wellington,
1983; Glynn, 2003). Porites reefs are found at Clipperton
Atoll (Glynn et al., 1996), in Costa Rica (Cortés and
Jiménez, 2003), and in some areas of the Galápagos
Islands (Glynn and Wellington, 1983; Glynn, 2003). Other
species that are important as reef builders in particular
localities are Pocillopora eydouxi in Colombia (Glynn
et al., 1982), Panamá (Guzmán et al., 1991), and Costa
Rica (Cortés, 1996/1997); and Pavona clavus,
Psammocora stellata, and Leptoseris papyracea in Costa
Rica (Cortés, 1990; Jiménez, 2001; Bezy et al., 2006).
Coral communities that increase structural heterogeneity on sand/rubble or rocky surfaces are very important in
the ETP. In some areas, they may be important contributors to the local benthic ecology of non-reefal habitats.
These coral communities can be formed by scattered colonies of the main reef builders growing over basalts or
sand/rubble, as in Bahía Culebra, Costa Rica (Jiménez,
2001), or by non-reef-building corals, e.g., Diaseris
distorta and Psammocora stellata in deep reefs in the
Galápagos Islands (Feingold, 1995, 1996); and Diaseris
distorta and Porites sverdrupi in the Gulf of California
(Feingold et al., 2009).
In many regions, the predominant reef builders in shallow waters are pocilloporids, while in deeper waters the
main reef builders are Porites lobata and Pavona spp.,
for example, in Panamá (Glynn et al., 1972), Galápagos
Islands (Glynn and Wellington, 1983), and Costa Rica
(Guzman and Cortés, 1989; Cortés, 1990; Guzman and
Cortés, 2007). The shallow reefs in the ETP are physically
controlled by wave action and low tidal exposure, while
deeper sections are biologically controlled mainly by
predation and competition (Glynn, 1976; Guzman and
Cortés, 1989).
Threats/impacts
El Nin ˜ o-Southern Oscillation (ENSO)
ENSO events are atmospheric–oceanographic phenomena which in the ETP manifest themselves as warming
episodes with devastating consequences to corals and
corals reefs (Glynn, 2000). These warming events have
caused the most damage to coral reefs in the entire ETP.
The first major recorded event was during the 1982–83
El Niño, causing coral mortalities ranging from 50 to
99% (Glynn, 1984). Glynn et al. (1988) determined that
the greater the temperature anomaly, the longer the
warming event, and the faster the warming increased, the
more was the impact on the coral communities and reefs.
Subsequent warming events associated with ENSO, especially the 1997–1998 event, also caused significant impacts
(Glynn and Colley, 2001). All regions of the ETP have been
affected: México (Reyes-Bonilla, 2003), Costa Rica
(Guzman and Cortés, 2001; Jiménez and Cortés, 2001;
Jiménez et al., 2001; Jiménez and Cortés, 2003; Guzman
and Cortés, 2007), Panamá (Glynn, 1990; Maté, 2003),
Galápagos, and mainland Ecuador (Glynn, 2003). Recovery has been observed in some areas but it has been slow
(Guzman and Cortés, 2001; Guzman and Cortés, 2007).
Subaerial exposure
Extreme low tides have been observed in the ETP and
have limited local effects, but significant for reef flats
depending on the season and time of day. These exposures
of the shallow reef may be due to extremely low astronomical tides and ENSO-related sea-level drop (Glynn, 1984;
Eakin and Glynn, 1996). Exposure of corals have been
illustrated from Panama (Eakin and Glynn, 1996; Maté,
2003) and Ecuador (Glynn, 2003).
Sedimentation
The presence of terrigenous sedimentation in coral reefs is
a major cause of reef deterioration worldwide (Fabricius,
2005). Excessive amounts will bury and kill corals, while
low concentrations also have negative effects. The corals
must spend energy to clean themselves by ciliary action,
polyp expansion, and/or mucus sheet production all with
354
EASTERN TROPICAL PACIFIC CORAL REEFS
relief of the reef structure is inherited from the noncarbonate substrate, with some large massive corals present. At Isla del Caño, the oldest framework was 2,000
year BP, while at Isla del Coco and the Galápagos Islands
samples from the base of the largest Porites colonies yield
dates of between 320 and 450 years BP (Macintyre et al.,
1992).
Postdepositional alteration of corals is minimal in the
ETP (Glynn and Macintyre, 1977; Cortés et al., 1994), as
is subsequent reef consolidation (Cortés, 1997; Manzello
et al., 2008). This may be due to the rapid accumulation
rates, lack of high turbulance, and, in general, low pH of
the surrounding waters (Glynn and Macintyre, 1977;
Cortés, 1997; Manzello et al., 2008). These reefs are subject to rapid bioerosion (Cortés, 1997; Fonseca et al.,
2006), resulting in very few examples of exposed Holocene reefs (Glynn and Wellington, 1983; Denyer and
Cortés, 2001). ETP reefs are very fragile and, in general,
are obliterated before preservation (Cortés, 1993). Branching corals are uncemented, and massive colonies are usually highly bioeroded and in many places unattached to
the substrate (Scott and Risk, 1988; Fonseca, 1999). Reef
framework is also bioeroded, especially once the coral dies
(Glynn et al., 1979; Glynn, 1988; Colgan, 1990; Glynn
and Colgan, 1992; Eakin, 1996; Reaka-Kudla et al.,
1996; Fonseca et al., 2006). In conclusion, reef preservation is very low in the ETP (Cortés, 1997).
Types of coral reefs
There are at least 35 species of zooxanthellate corals in
the ETP (Reyes-Bonilla, 2002), but only three are important reef builders across the entire region (Pocillopora
damicornis, P. elegans and Porites lobata). Pocillopora
spp. reefs are found in México (Reyes-Bonilla, 2003),
Costa Rica (Cortés, 1996/1997; Cortés and Jiménez,
2003), Panamá (Maté, 2003; Guzman et al., 2004, 2008),
Colombia (Glynn et al., 1982; Zapata and Vargas-Ángel,
2003), and the Galápagos Islands (Glynn and Wellington,
1983; Glynn, 2003). Porites reefs are found at Clipperton
Atoll (Glynn et al., 1996), in Costa Rica (Cortés and
Jiménez, 2003), and in some areas of the Galápagos
Islands (Glynn and Wellington, 1983; Glynn, 2003). Other
species that are important as reef builders in particular
localities are Pocillopora eydouxi in Colombia (Glynn
et al., 1982), Panamá (Guzmán et al., 1991), and Costa
Rica (Cortés, 1996/1997); and Pavona clavus,
Psammocora stellata, and Leptoseris papyracea in Costa
Rica (Cortés, 1990; Jiménez, 2001; Bezy et al., 2006).
Coral communities that increase structural heterogeneity on sand/rubble or rocky surfaces are very important in
the ETP. In some areas, they may be important contributors to the local benthic ecology of non-reefal habitats.
These coral communities can be formed by scattered colonies of the main reef builders growing over basalts or
sand/rubble, as in Bahía Culebra, Costa Rica (Jiménez,
2001), or by non-reef-building corals, e.g., Diaseris
distorta and Psammocora stellata in deep reefs in the
Galápagos Islands (Feingold, 1995, 1996); and Diaseris
distorta and Porites sverdrupi in the Gulf of California
(Feingold et al., 2009).
In many regions, the predominant reef builders in shallow waters are pocilloporids, while in deeper waters the
main reef builders are Porites lobata and Pavona spp.,
for example, in Panamá (Glynn et al., 1972), Galápagos
Islands (Glynn and Wellington, 1983), and Costa Rica
(Guzman and Cortés, 1989; Cortés, 1990; Guzman and
Cortés, 2007). The shallow reefs in the ETP are physically
controlled by wave action and low tidal exposure, while
deeper sections are biologically controlled mainly by
predation and competition (Glynn, 1976; Guzman and
Cortés, 1989).
Threats/impacts
El Nin ˜ o-Southern Oscillation (ENSO)
ENSO events are atmospheric–oceanographic phenomena which in the ETP manifest themselves as warming
episodes with devastating consequences to corals and
corals reefs (Glynn, 2000). These warming events have
caused the most damage to coral reefs in the entire ETP.
The first major recorded event was during the 1982–83
El Niño, causing coral mortalities ranging from 50 to
99% (Glynn, 1984). Glynn et al. (1988) determined that
the greater the temperature anomaly, the longer the
warming event, and the faster the warming increased, the
more was the impact on the coral communities and reefs.
Subsequent warming events associated with ENSO, especially the 1997–1998 event, also caused significant impacts
(Glynn and Colley, 2001). All regions of the ETP have been
affected: México (Reyes-Bonilla, 2003), Costa Rica
(Guzman and Cortés, 2001; Jiménez and Cortés, 2001;
Jiménez et al., 2001; Jiménez and Cortés, 2003; Guzman
and Cortés, 2007), Panamá (Glynn, 1990; Maté, 2003),
Galápagos, and mainland Ecuador (Glynn, 2003). Recovery has been observed in some areas but it has been slow
(Guzman and Cortés, 2001; Guzman and Cortés, 2007).
Subaerial exposure
Extreme low tides have been observed in the ETP and
have limited local effects, but significant for reef flats
depending on the season and time of day. These exposures
of the shallow reef may be due to extremely low astronomical tides and ENSO-related sea-level drop (Glynn, 1984;
Eakin and Glynn, 1996). Exposure of corals have been
illustrated from Panama (Eakin and Glynn, 1996; Maté,
2003) and Ecuador (Glynn, 2003).
Sedimentation
The presence of terrigenous sedimentation in coral reefs is
a major cause of reef deterioration worldwide (Fabricius,
2005). Excessive amounts will bury and kill corals, while
low concentrations also have negative effects. The corals
must spend energy to clean themselves by ciliary action,
polyp expansion, and/or mucus sheet production all with
354
EASTERN TROPICAL PACIFIC CORAL REEFS