The Estuary Ecosystem of Buenaventura Bay, Colombia
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nula), crabs (Sesarma spp., Armases), amphipods (Talitridae), and some
collembolan insects (Archisotoma, Cryptopigas, Axelsonia).
Particulate and dissolved organic matter derived from mangrove litter
is the main food source for deposit-feeders (77% of all species) in both
mangrove sediments and in the sediments of adjacent mud flats and sand
beaches. Filter- and suspension-feeding bivalves, polychaetes, and
barnacles on mangrove prop roots, or species like the ghost crab Ocypode
spp. on muddy and sandy sediments, consume dissolved organic matter
and phytoplankton. Small filter-feeding fish ( < 15 em total length) present
a diverse and abundant trophic group. The herring Opisthonema libertate
feeds exclusively on zooplankton (23-99% of gut content) while the
anchovy Cetengraulis mysticetus feeds on diatoms like Thalassionema
(29.13 %) and Skeletonema (23.65 %). Benthic fish (i.e. Mugil curema) feed
on bottom diatoms (Navicula 57% in number of individuals; Coscinodiscus 8.5 %; Fragillaria 15.4 %) while prawns (Penaeidae) ingest zooplankton, phytoplankton, and DOM and POM.
Gastropods (Natica unifasciata, Muricanthus radix, Thais kiosquiformis, T. biserialis), crustaceans ( Goniopsis pulchra, Aratus pisonii, Panopeus
purpureus, P. chilensis, Eurypanopeus transversus, Callinectes toxotes, Callinectes arcuatus) and small fishes prey on benthic fauna in the mangroves.
The crabs are omnivorous, for example, the diet of Callinectes arcuatus
consists of fishes (17.5 %), mollusks (15.9 %), shrimps (12.9 %), and vegetal
matter (7. 7%). Several abundant fish species, which are buried during low
tide or enter with high tide, like the drum (Stellifer oscitans), feed on
benthic crustaceans (0.7% of the body weight), and the catfish (Arius seemanni) and the threadfin (Polydactylus approximatus) forage on crustaceans and fishes. During high tide several, mostly carnivorous marine fish
visit estuarine waters and mangrove areas in search of food. The diet of the
flatfish (Cy clops etta querna) is composed of penaeid prawns ( 80.6 %) and
goby fishes (19.4%). The tusky drum (Cynoscion phoxocephalus) ingests
the prawn Xiphopenaeus (2.2 %) and small pelagic fishes (0.68 %). Pelagic
species like the jack ( Caranx can in us) feed on crabs and larvae (3.2% of
body weight), the rocky snapper (Lutjanus guttatus) mostly ingests snapping shrimps (Alpheidae) and stomatopods (23.2% of gut content), and
the diet of grunt (Pomadasys panamensis) is composed of prawns and
crabs (73-98% of gut content) and small pelagic fishes ( Gobiidae, Engraulidae, Clupeidae; 2-27% of gut content).
In intertidal habitats, the predation by seabirds (Pelecanus, Phalacrocorax, Larus, Sterna) and migratory shorebirds represents an important
export of energy (137.5 tons year-' and 1.05 tons year- 1 , respectively) out of
Buenaventura Bay (Morales 1998). In contrast, terrestrial species like Egretta (2.7 tons year-') and Butorides (0.5 tons year- 1 ), which feed on intertidal
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nula), crabs (Sesarma spp., Armases), amphipods (Talitridae), and some
collembolan insects (Archisotoma, Cryptopigas, Axelsonia).
Particulate and dissolved organic matter derived from mangrove litter
is the main food source for deposit-feeders (77% of all species) in both
mangrove sediments and in the sediments of adjacent mud flats and sand
beaches. Filter- and suspension-feeding bivalves, polychaetes, and
barnacles on mangrove prop roots, or species like the ghost crab Ocypode
spp. on muddy and sandy sediments, consume dissolved organic matter
and phytoplankton. Small filter-feeding fish ( < 15 em total length) present
a diverse and abundant trophic group. The herring Opisthonema libertate
feeds exclusively on zooplankton (23-99% of gut content) while the
anchovy Cetengraulis mysticetus feeds on diatoms like Thalassionema
(29.13 %) and Skeletonema (23.65 %). Benthic fish (i.e. Mugil curema) feed
on bottom diatoms (Navicula 57% in number of individuals; Coscinodiscus 8.5 %; Fragillaria 15.4 %) while prawns (Penaeidae) ingest zooplankton, phytoplankton, and DOM and POM.
Gastropods (Natica unifasciata, Muricanthus radix, Thais kiosquiformis, T. biserialis), crustaceans ( Goniopsis pulchra, Aratus pisonii, Panopeus
purpureus, P. chilensis, Eurypanopeus transversus, Callinectes toxotes, Callinectes arcuatus) and small fishes prey on benthic fauna in the mangroves.
The crabs are omnivorous, for example, the diet of Callinectes arcuatus
consists of fishes (17.5 %), mollusks (15.9 %), shrimps (12.9 %), and vegetal
matter (7. 7%). Several abundant fish species, which are buried during low
tide or enter with high tide, like the drum (Stellifer oscitans), feed on
benthic crustaceans (0.7% of the body weight), and the catfish (Arius seemanni) and the threadfin (Polydactylus approximatus) forage on crustaceans and fishes. During high tide several, mostly carnivorous marine fish
visit estuarine waters and mangrove areas in search of food. The diet of the
flatfish (Cy clops etta querna) is composed of penaeid prawns ( 80.6 %) and
goby fishes (19.4%). The tusky drum (Cynoscion phoxocephalus) ingests
the prawn Xiphopenaeus (2.2 %) and small pelagic fishes (0.68 %). Pelagic
species like the jack ( Caranx can in us) feed on crabs and larvae (3.2% of
body weight), the rocky snapper (Lutjanus guttatus) mostly ingests snapping shrimps (Alpheidae) and stomatopods (23.2% of gut content), and
the diet of grunt (Pomadasys panamensis) is composed of prawns and
crabs (73-98% of gut content) and small pelagic fishes ( Gobiidae, Engraulidae, Clupeidae; 2-27% of gut content).
In intertidal habitats, the predation by seabirds (Pelecanus, Phalacrocorax, Larus, Sterna) and migratory shorebirds represents an important
export of energy (137.5 tons year-' and 1.05 tons year- 1 , respectively) out of
Buenaventura Bay (Morales 1998). In contrast, terrestrial species like Egretta (2.7 tons year-') and Butorides (0.5 tons year- 1 ), which feed on intertidal