Modeling the connectivity of Juan Fernandez rock lobster (Jasus frontalis), subpopulations through a biophysical model
Authored by Carolina Parada, Javier Porobic, Billy Ernst, Samuel E Hormazabal, Vincent Combes
Date Published: 2012
DOI: 10.3856/vol40-issue3-fulltext-11
Sponsors:
Chilean National Commission for Scientific and Technological Research (CONICYT)
Platforms:
No platforms listed
Model Documentation:
Other Narrative
Flow charts
Mathematical description
Model Code URLs:
Model code not found
Abstract
Located approximately 360 nm off the coast of Chile there is a disjoint
realm of two small oceanic islands systems, the Juan Fernandez and the
Desventuradas archipelago. Currently the local economy of the islands is
almost exclusively supported by the harvest and trade of marine
resources, focusing mainly on the exploitation of the rock lobster
(Jasus frontalis). This endemic species is distributed in both
archipelagos, forming a metapopulation, whose population structure and
dynamic is modulated by oceanographic forcing, especially during its
extended planktonic larval phase. The population structure and the
conection-retention within and between islands was assessed, based on
the use of coupled biophysical model (the hidrodynamics model OFES and
an individual-based model of J. frontalis). The analysis of the
hydrodynamic model predictions showed the presence of mesoscale
structures associated with the islands systems. The simulation results
indicated significant levels of connectivity-retention within and
between island systems showing also a strong interannual variation of
these. Biophysical modeling results indicated that recruitment
varibility associated with the Juan Fernandez archipelago depends mainly
on larvae originated within this system, which as well will contribute
with recruits to the Desventuradas archipelago. The sensitivity analysis
of the biophysical model to identify the potential biophysical forcing
of the dependent variables of the model (e.g. connectivity-retention
index), resulted in that temporal and spatial patterns reproductive
larval stage duration and season (year) are highly significant factors.
Finally, a metapopulation structure for J. frontalis, with a high level
of connectivity in the archipelago of Juan Fernandez and a considerable
amount of larvae in the Desventuradas islands is proposed. These fluxes
are determined mainly by the coupling between prevailing biological and
oceanographic factors.
Tags
New-zealand
Population connectivity
Homarus-americanus
Western-australia
Nursery areas
Marine
populations
Southern benguela
Larval-stage growth
Panulirus-cygnus
Puerulus settlement