Trophic role of small pelagic fishes in a tropical upwelling ecosystem
Duarte, L.O.; García, C.B. (2004). Trophic role of small pelagic fishes in a tropical upwelling ecosystem. Ecol. Model. 172(2-4): 323-338
In: Ecological Modelling. Elsevier: Amsterdam; Lausanne; New York; Oxford; Shannon; Tokyo. ISSN 0304-3800; e-ISSN 1872-7026, more
Also appears in:Christensen, V.; Maclean, J.L. (Ed.) (2004). Placing fisheries in their ecosystem context. Ecological Modelling, 172(2-4). Elsevier: Amsterdam. 103-440 pp., more
|   |
| Keywords |
Ecosystems
Fisheries > Marine fisheries > Pelagic fisheries
Food webs
Interspecific relationships > Predation
Motion > Water motion > Vertical water movement > Upwelling
Simulation
Trophic structure
ASW, Colombia [Marine Regions]
Marine/Coastal |
| Authors | | Top |
- Duarte, L.O.
- García, C.B.
|
|
|
| Abstract |
On the basis of an Ecopath model and Ecosim model simulations, the trophic role of small pelagic fish in the Gulf of Salamanca,a tropical upwelling ecosystem on the Caribbean coast of Colombia, was explored using a combination of fishing vulnerabilitiesand harvest scenarios. Dynamic simulated changes in the biomass of small pelagic fish caused reallocation of the biomass ofhigher trophic-level organisms but not of lower trophic-level organisms (plankton). This was attributed to bottom-up controlexerted by small pelagic fish on pelagic predatory fish, the highest trophic-level predators with a diverse diet trough whichconsequences of changes in small pelagic fish biomass propagate. Plankton biomass remained almost unchanged, althoughplankton is the main food of small pelagic fish. Overall, the results indicate that small pelagic fish play an important role in thisecosystem because perturbations of their biomass (brought about by fishing) propagate through the upper part of the system.However, they have little effect on the lower trophic-level groups. By extension, the postulated crucial “wasp-waist” role ofintermediate trophic levels occupied by small pelagic fish in temperate and subtropical most productive upwelling regions maynot have a full equivalent in tropical less productive upwelling areas. |
|
