EDP Sciences Journals List
Home Document
Subscriber Authentication Point
Free access article

Issue Aquat. Living Resour.
Volume 22, Number 2, April-June 2009
Fish Stock Assessments Using Surveys and Indicators
Page(s) 233 - 241
DOI 10.1051/alr/2009024
Published online 17 June 2009

Aquat. Living Resour. 22 (2009) 233-241
DOI: 10.1051/alr/2009024

ALADYM: an age and length-based single species simulator for exploring alternative management strategies

Giuseppe Lembo1, Alvaro Abella2, Fabio Fiorentino3, Sergio Martino1 and Maria-Teresa Spedicato1

1  COISPA Tecnologia & Ricerca, Via dei trulli 18-20, 70126 Bari, Italy
2  ARPAT-AREA MARE, Via Marradi 114, Livorno, Italy
3  IAMC-CNR, Via L. Vaccara 61, Mazara del Vallo (TP), Italy

Received 29 August 2008; Accepted 29 January 2009; Published online 17 June 2009.

Abstract - ALADYM (age-length based dynamic model) is an age-length based simulation model designed to predict the consequences of management scenarios on a single population, in terms of different metrics and indicators. Removals are simulated as total mortality modulated using a selectivity pattern and a fishing activity coefficient. ALADYM uses the classical equations of population dynamics to create a tool that uses fishery-independent information (e.g. from trawl surveys) as the primary source. The formulation of population dynamics at a small time scale (month) allows to model the effects of harvest controls that evolve through the year, which is particularly useful for fast growing species. The possibility of specifying a vector of natural mortality by age/length makes the model more suitable for situations where stocks are exploited at an early life stage, as in many Mediterranean fisheries, while introducing variations along the time of the harvesting pattern accounts for non-equilibrium situations. Stochastic effects can be added to some key life-history traits to incorporate uncertainty in input parameters and in their relationships. ALADYM can be used for a range of applications such as comparing management strategies, evaluating indicator changes or searching for reference points.


Key words: Fish population dynamics / Simulation model / Fishery-independent approach / Fishery management

Corresponding author: lembo@coispa.it

© EDP Sciences, IFREMER, IRD 2009


What is OpenURL?

The OpenURL standard is a protocol for transmission of metadata describing the resource that you wish to access. An OpenURL link contains article metadata and directs it to the OpenURL server of your choice. The OpenURL server can provide access to the resource and also offer complementary services (specific search engine, export of references...). The OpenURL link can be generated by different means.
  • If your librarian has set up your subscription with an OpenURL resolver, OpenURL links appear automatically on the abstract pages.
  • You can define your own OpenURL resolver with your EDPS Account. In this case your choice will be given priority over that of your library.
  • You can use an add-on for your browser (Firefox or I.E.) to display OpenURL links on a page (see http://www.openly.com/openurlref/). You should disable this module if you wish to use the OpenURL server that you or your library have defined.