Biomass ratios for simulations involving an additional fictive fleet in the Banc (A) and the loss of the Banc as a habitat (B) for the three models (P30, Base, M30) by group of species (31spp, and coastal, pelagics and shelf functional groups).

<p>Biomass ratios for simulations involving an additional fictive fleet in the Banc (A) and the loss of the Banc as a habitat (B) for the three models (P30, Base, M30) by group of species (31spp, and coastal, pelagics and shelf functional groups).</p

The Mauritanian shelf (the study area) and the Banc d’Arguin National Park (delimited with the black line).

<p>The study area covers 33,224² including the Banc d’Arguin (6,450 km²).</p

Observed and predicted biomass (t·km⁻²) for the period 1991–2006 using the base, M30 and P30 models.

<p>Except for Pelagic L, only groups with time series are shown.</p

Input and output parameters for the Base Ecopath model.^*

<p>* Values estimated in Ecopath are in bold.TL: trophic level; Biom: biomass, Z: total mortality; P/B and Q/B: production and consumption per unit of biomass; EE: ecotrophic efficiency; P/Q: gross efficiency; BA: biomass accumulation; Artis. Dem. Pel. are the artisanal, demersal and pelagic fleets.</p

Relative biomass compared to the status quo under two scenarios: adding the fictive fleet in the Banc (B_fict/B_Sq in x-axis) and the habitat loss in the Banc (B_Loss/B_Sq in y-axis).

<p>A = adult, J =  juvenile.</p

Portion of the production (A), and catches (t·km⁻²·year⁻¹, (B) originating from the Banc d’Arguin, through direct or indirect pathways, for the 31 Ecopath groups of higher TL.

<p>Portion of the production (A), and catches (t·km⁻²·year⁻¹, (B) originating from the Banc d’Arguin, through direct or indirect pathways, for the 31 Ecopath groups of higher TL.</p

Trophic spectra on the dependency of the Mauritanian EEZ ecosystem to the Banc d’Arguin: A. proportion of the production originating directly or indirectly from the Banc; B. portion of the biomass by level of dependency of the various Ecopath groups to the Banc; C. current fishing mortalities (year⁻¹) for these groups (B and C are referring to the base model only).

<p>Trophic spectra on the dependency of the Mauritanian EEZ ecosystem to the Banc d’Arguin: A. proportion of the production originating directly or indirectly from the Banc; B. portion of the biomass by level of dependency of the various Ecopath groups to the Banc; C. current fishing mortalities (year⁻¹) for these groups (B and C are referring to the base model only).</p

Observed and predicted catches for the period 1991–2006 using the Base, M30 and P30 models.

<p>Observed and predicted catches for the period 1991–2006 using the Base, M30 and P30 models.</p

Biomass (A) and catch (B) spectra for the Base model and scenario of additional fishing (fictive fleet in the Banc and habitat loss).

<p>Biomass (A) and catch (B) spectra for the Base model and scenario of additional fishing (fictive fleet in the Banc and habitat loss).</p

Percent consumption (Q), production (P1 for animals only, P2 including primary producers) and catch (Y) of the Mauritanian shelf coming from invertebrates from the Banc d’Arguin (BA), both directly and indirectly through the food web (total): on the left for the Base, M30 and P30 models, and on the right for the various types of functional group (number of groups).

<p>Percent consumption (Q), production (P1 for animals only, P2 including primary producers) and catch (Y) of the Mauritanian shelf coming from invertebrates from the Banc d’Arguin (BA), both directly and indirectly through the food web (total): on the left for the Base, M30 and P30 models, and on the right for the various types of functional group (number of groups).</p