Relationships between population spatial occupation and population dynamics

International audience Population dynamics is commonly described non-spatially using parameters of population demography and vital traits. Population spatial organisation is therefore considered implicit and its importance in the population dynamics ignored. The present study evidences on a variety...

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Bibliographic Details
Main Authors: Woillez, Mathieu, Petitgas, Pierre, Rivoirard, Jacques, Fernandes, Paul, Ter Hoftstede, Remment, Korsbrekke, Knut, Orlowski, Andrej, Spedicato, Maria Teresa, Politou, Chrissi-Yianna
Other Authors: Centre de Géosciences (GEOSCIENCES), MINES ParisTech - École nationale supérieure des mines de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Laboratoire Ressources Halieutiques (LRH), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), COISPA Tecnologia & Ricerca, COISPA
Format: Conference Object
Language:English
Published: HAL CCSD 2006
Subjects:
Online Access:https://hal-mines-paristech.archives-ouvertes.fr/hal-00580013
Description
Summary:International audience Population dynamics is commonly described non-spatially using parameters of population demography and vital traits. Population spatial organisation is therefore considered implicit and its importance in the population dynamics ignored. The present study evidences on a variety of stocks correlation between population spatial distribution indices, population abundance, recruitment and mortality. Series of research fisheries monitoring surveys were considered for a range of different stocks (cod, herring, anchovy, hake, mullet) in different regions of the North East Atlantic and Mediterranean (North Sea, Barents Sea, Baltic Sea, Bay of Biscay, Tyrrhenian Sea, Ionian Sea and Aegean Sea). For each population, each age and each year, 9 spatial indices were computed that characterised the spatial distribution in their centre of gravity, inertia, anisotropy, extension areas, number of patches and microscale structure. For each population and age, spatial indices were linearly regressed on the abundance, on the following recruitment, and on the mortality residuals (as a constant mortality has been fitted on cohort curves). A metaanalysis table was constructed that showed the number of times that correlations were significant. The result is that spatial indices provide additional indicators for assessing population status and could be helpful in the context of stock decline and habitat loss.