English   español  
Please use this identifier to cite or link to this item: http://hdl.handle.net/10261/94396
logo share SHARE   Add this article to your Mendeley library MendeleyBASE
Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL
Exportar a otros formatos:


Early life history dynamics of European anchovy in the Western Mediterranean: an Individual-Based Modelling approach

Other TitlesDinámica de los primeros estadios de desarrollo en la anchoa europea en el Mediterráneo occidental: una aproximación usando Modelos Basados en Individuos
AuthorsOspina-Álvarez, Andrés
AdvisorPalomera, Isabel ; Catalán, Ignacio Alberto
Issue Date2012
PublisherUniversidad de Barcelona
AbstractThe thesis has been organized in two parts written in English and Spanish. The Part 1, Section 1, written in Spanish, deals with introductory issues. The broad philosophical modelling approach is presented along with a general description of individual-based modelling. The coupling of IBMs to hydrodynamic models is explained and the simulation procedures are outlined. A general introduction about life history of anchovy in the NW Mediterranean and management issues is provided. The Section 2 deals with the aims, scope and hypothesis are detailed and the thesis structure is explained. The section 4 synthesises the results of the thesis in terms of the hypotheses tested and addresses the implications of the results for understanding the life history of anchovy in the NW Mediterranean. Current patterns in anchovy spawning behaviour are examined in light of the present ndings and future directions for research are suggested. The second Part, \Chapters and publications>, presents the papers submitted as Journal articles. Chapters 1 to 5 are written in English. Chapter 1 explores the interaction between the biological properties of anchovy eggs (i.e. radius, morphology and buoyancy) and the vertical position of the eggs in the water column. Chapter 1 describes the implementation of a egg-buoyancy sub-model in the SEIBM to simulate the depth adjustment of anchovy eggs during development to variations of water density during the transport from spawning grounds to the location where hatching occurs. Chapter 2 looks at the vertical movement of anchovy larvae in the model caused by physical and biological factors. The aim of this chapter is to assess the relevance of diel vertical migration (DVM) as a mechanism involved in the transport of European anchovy larvae towards nursery areas taking into account age/stage-dependent vertical migration (i.e., the maximum migration). Chapter 2 describes a simplied vertical migration sub-model for anchovy larvae included in an Individual-based (IBM) hydrodynamic coupled model. The eect of vertical movement of anchovy larvae on transport and retention is also examined. Chapter 3 incorporates a temperature-dependent development rate model to explore the possible eects this could have on levels of recruitment to the two proposed nursery grounds. Chapter 3 is a back-calculation experiment using the SEIBM hydrodynamic coupled model and deals with the following hypotheses: 1) that the plausible eective spawning zones (those generating post-larvae at the known nursery grounds) are mainly found at the vicinity of a suggested spawning ground; 2) that observed back-calculated growth of larvae sampled in the nursery grounds can be reasonably simulated by a simple temperature-dependent growth model, and 3) that including biological behaviour to the model signicantly improves the match between observed and modelled larval recruitment and/or growth patterns. The aim of Chapter 4 is provide a method to estimate the daily egg production (number of stage-I eggs per square meter of sea surface) from adult biomass obtained by mean of acoustic surveys and historical fecundity data. Chapter 4 considers dierences in fecundity of each size class of the anchovy stock and uses a size-based fecundity model to examine how this manifests in regional dierences of reproductive output by anchovy in the NW Mediterranean. Chapter 5 is the integration of all sub-models developed in the SEIBM to explore how spawner location and nal nursery ground in uence estimated levels of recruitment from year to year. In Chapter 5, an inter-annual SEIBM experiment is used to examine transport, retention and dispersion processes in the nursery area and hypothesise about the possible essential nursery habitats for anchovy larvae in the NW Mediterranean
DescriptionMemoria de tesis doctoral presentada por Andrés Ospina Álvarez para optar al grado de Doctor en Ciencias del Mar de la Universitat de Barcelona (UB), realizada bajo la dirección de la Dra. Isabel Palomera Laforga del Institut de Ciències del Mar (ICM-CSIC) y del Dr. Ignacio A. Catalán Alemany del Instituto Mediterráneo de Estudios Avanzados (IMEDEA-CSIC/UIB).-- 245 pages
Appears in Collections:(IMEDEA) Tesis
(ICM) Tesis
Files in This Item:
File Description SizeFormat 
Ospina_Thesis_2012.pdf18,44 MBAdobe PDFThumbnail
Show full item record
Review this work

WARNING: Items in Digital.CSIC are protected by copyright, with all rights reserved, unless otherwise indicated.