Eastern Pacific Coral Reef Ecosystem
299
eastern Pacific (Glynn 1982), their effects are usually low level and localized. Preferential feeding by the sea star Acanthaster planci can influence
the species composition of coral communities, but no outbreaks resulting
in mass coral mortality are known.
Unfortunately, as awareness of the occurrence of coral reefs in the
eastern Pacific increases they become more exposed to various hazards
from humankind (Glynn 1997). In a recent analysis, estimated anthropogenic threats to coral reefs were considered to be high off the Pacific coasts
of Costa Rica, Panama and Colombia based on: (1) coastal development,
(2) overexploitation and destructive fishing practices, (3) inland pollution
and erosion, and (4) marine pollution (Bryant et al. 1998). High levels of
siltation caused by accelerated coastal erosion have degraded coral reefs in
Costa Rica, Colombia and Ecuador. Although all other coral reef areas in
the eastern Pacific were classified as low risk, it is highly likely that significant damage is also occurring at many other sites, but is simply not reported. This will become evident as studies expand in the region. For example,
construction projects related to harbor and hotel development are believed
to have killed two coral reefs at Huatulco, Mexico. In addition, the harvesting of corals for the curio trade continues to be a serious problem ( Guzman and Cortes 1993). This activity has virtually eliminated pocilloporid
corals from Acapulco (Mexico), Bahia Culebra (Costa Rica), Taboga Island
(Panama), and parts of the coast of Ecuador. At Isla Pelado, Ayangue, and
Salango Island, Ecuador, prodigious numbers of corals have been removed
in recent years. According to a local fisherman, truckloads of live corals
have been removed from Salango Island, which falls within the jurisdiction
of the Parque Nacional de Machalilla. Over-fishing may well be responsible
for some ecological imbalances on coral reefs that could prolong recovery
from other disturbances, but such effects have not been studied in the
eastern Pacific. For example, a marked reduction in (1) fish herbivores
could favor benthic algal growth over coral recruitment, and (2) fish invertivores could favor increased abundance of bioeroding sea urchins.
19.8 Management Needs
At least 22 existing and 6 proposed marine protected areas (MPAs) harboring coral communities and/or coral reefs are presently recognized in the
tropical eastern Pacific (Table 19.1). This is a major increase from 7 years
ago when only seven existing and one proposed MPA were listed regionally (UNEP/IUCN 1988). Most existing MPAs are in Mexico, Costa Rica,
Panama, Colombia and Ecuador. Important coral reef areas are located
299
eastern Pacific (Glynn 1982), their effects are usually low level and localized. Preferential feeding by the sea star Acanthaster planci can influence
the species composition of coral communities, but no outbreaks resulting
in mass coral mortality are known.
Unfortunately, as awareness of the occurrence of coral reefs in the
eastern Pacific increases they become more exposed to various hazards
from humankind (Glynn 1997). In a recent analysis, estimated anthropogenic threats to coral reefs were considered to be high off the Pacific coasts
of Costa Rica, Panama and Colombia based on: (1) coastal development,
(2) overexploitation and destructive fishing practices, (3) inland pollution
and erosion, and (4) marine pollution (Bryant et al. 1998). High levels of
siltation caused by accelerated coastal erosion have degraded coral reefs in
Costa Rica, Colombia and Ecuador. Although all other coral reef areas in
the eastern Pacific were classified as low risk, it is highly likely that significant damage is also occurring at many other sites, but is simply not reported. This will become evident as studies expand in the region. For example,
construction projects related to harbor and hotel development are believed
to have killed two coral reefs at Huatulco, Mexico. In addition, the harvesting of corals for the curio trade continues to be a serious problem ( Guzman and Cortes 1993). This activity has virtually eliminated pocilloporid
corals from Acapulco (Mexico), Bahia Culebra (Costa Rica), Taboga Island
(Panama), and parts of the coast of Ecuador. At Isla Pelado, Ayangue, and
Salango Island, Ecuador, prodigious numbers of corals have been removed
in recent years. According to a local fisherman, truckloads of live corals
have been removed from Salango Island, which falls within the jurisdiction
of the Parque Nacional de Machalilla. Over-fishing may well be responsible
for some ecological imbalances on coral reefs that could prolong recovery
from other disturbances, but such effects have not been studied in the
eastern Pacific. For example, a marked reduction in (1) fish herbivores
could favor benthic algal growth over coral recruitment, and (2) fish invertivores could favor increased abundance of bioeroding sea urchins.
19.8 Management Needs
At least 22 existing and 6 proposed marine protected areas (MPAs) harboring coral communities and/or coral reefs are presently recognized in the
tropical eastern Pacific (Table 19.1). This is a major increase from 7 years
ago when only seven existing and one proposed MPA were listed regionally (UNEP/IUCN 1988). Most existing MPAs are in Mexico, Costa Rica,
Panama, Colombia and Ecuador. Important coral reef areas are located