File(s) under permanent embargo
Shifts in plankton size spectra modulate growth and coexistence of anchovy and sardine in upwelling systems
journal contribution
posted on 2023-05-18, 16:37 authored by Canales, TM, Law, R, Julia BlanchardJulia BlanchardFluctuations in the abundance of anchovy (Engraulis spp.) and sardine (Sardinops sagax) are widespread in marine ecosystems, but the causes still remain uncertain. Differences between the planktonic prey availability, selectivity, and predation between anchovy and sardine have been suggested as factors influencing their dynamics. Using a dynamical multispecies size-spectrum model, we explore the consequences of changes in plankton size composition, together with intraguild predation and cannibalism, on the coexistence of these species. The shift towards smaller plankton has led to a reduction in the growth rate of both species. The effect was more deleterious on anchovy growth because it is unable to filter small particles. In model scenarios that included the effects of cannibalism and predation, anchovy typically collapsed under conditions favouring smaller sized plankton. The two species coexisted under conditions of larger sized plankton, although strong predation in conjunction with weak cannibalism led to the loss of sardine. The model provides new testable predictions for the consequences of plankton size structure on anchovy and sardine fluctuations. Further empirical work is needed to test these predictions in the context of climate change.
History
Publication title
Canadian Journal of Fisheries and Aquatic SciencesVolume
73Issue
4Pagination
611-621ISSN
0706-652XDepartment/School
Institute for Marine and Antarctic StudiesPublisher
Natl Research Council CanadaPlace of publication
Research Journals, Montreal Rd, Ottawa, Canada, Ontario, K1A 0R6Rights statement
Copyright 2015 the AuthorRepository Status
- Restricted