@article{fdi:010092000,
  title = {{E}stimating the copepod biomass in the {N}orth {W}est {A}frican upwelling system using a bi-frequency acoustic approach},
  author = {{D}iogoul, {N}. and {B}rehmer, {P}atrice and {K}iko, {R}. and {P}errot, {Y}annick and {L}ebourges {D}haussy, {A}nne and {R}odrigues, {E}. and {T}hiam, {A}. and {M}ouget, {A}. and {E}l {A}youbi, {S}. and {S}arr{\'e}, {A}.},
  editor = {},
  language = {{ENG}},
  abstract = {{T}he {C}anary {C}urrent {L}arge {M}arine {E}cosystem ({CCLME}) is one of the most productive {L}arge {M}arine {E}cosystems worldwide. {A}ssessing the abundance, biomass and distribution of zooplankton in the southern part of this system, off the coast of {W}est {A}frica, remains challenging due to limited sampling efforts and data availability. {H}owever, zooplankton is of primary importance for pelagic ecosystem functioning. {W}e applied an inversion method with combined analysis of acoustic and biological data for copepod discrimination using a bi-frequency (38 and 120 k{H}z) approach. {L}arge copepods with equivalent spherical radii > 0.5 mm were identified using differences in the mean volume backscattering strength ({MVBS}). {R}egarding abundance measured by net sampling, copepods strongly dominated the zooplankton community and the large fraction account for 18%. {T}his estimate correlated significantly with {MVBS} values that were obtained using an inverse algorithm. {W}e confirmed the utility of using 38 k{H}z for large copepod detection. {A}n epipelagic biomass of large copepod was estimated at 120-850 mg m(-2) in {M}arch during upwelling season. {I}t is worth noting that this estimation likely underestimates the true biomass due to inherent uncertainties associated with the measurement method. {W}e recommend future investigations in the interest of using only nighttime data to improve the sampling pattern, particularly on the upper part of the water column (< 10 m) as well as on the shallow part of the continental shelf (< 20 m depth) not covered by fisheries vessel. {N}evertheless, such high copepod biomass supports high fish production underlining the key role of copepod in the {CCLME}. {O}ur results open the way to the analysis of the fluctuation and trend of copepod biomass, along with three decades of fisheries acoustics data available in the region. {T}his helps to determine ecosystem changes, particularly under climate change, and to investigate the role of copepods in the southern {CCLME} carbon pump at the fine scale.},
  keywords = {{ATLANTIQUE} ; {MAURITANIE} ; {SENEGAL} ; {GAMBIE}},
  booktitle = {},
  journal = {{PL}o{S} {O}ne},
  volume = {19},
  numero = {9},
  pages = {e0308083 [25 p.]},
  ISSN = {1932-6203},
  year = {2024},
  DOI = {10.1371/journal.pone.0308083},
  URL = {https://www.documentation.ird.fr/hor/fdi:010092000},
}