@article{fdi:010040970,
  title = {{J}oint use of echosounding, fishing and video techniques to assess the structure of fish aggregations around moored {F}ish {A}ggregating {D}evices in {M}artinique ({L}esser {A}ntilles)},
  author = {{D}oray, {M}athieu and {J}osse, {E}rwan and {G}ervain, {P}. and {R}eynal, {L}. and {C}hantrel, {J}.},
  editor = {},
  language = {{ENG}},
  abstract = {{F}rom {A}pril 2003 to {A}pril 2004 monthly sea surveys were conducted around 2 fish aggregating devices ({FAD}s) moored at 2000 and 2500 m depth in {M}artinique ({L}esser {A}ntilles). {T}he use of a dual frequency splitbeam echosounder combined with an underwater camera and fishing methods allowed assessment of average space and time distribution of pelagic fish aggregated beneath the {FAD}s, as well as identification of their overall size and species composition. {A}t daytime, 4 fish aggregations were identified at each {FAD}, representing 4 distinct types: i) an aggregation of small juvenile tuna (mean fork length, {FL}: 30 cm) observed very close to the surface in 25% of daytime periods; ii) a small surface aggregation dominated by carangids, {C}aranx crysos, present in 65% of daytime periods; iii) a large subsurface aggregation observed during all daytime periods: this aggregation appeared to be primarily comprised of 58 cm {FL} blackfin tuna ({T}hunnus atlanticus), mixed with yellowfin ({T}hunnus albacares) and skipjack ({K}atsuwonus pelamis) tunas of the same size; and iv) sub-surface scattered large predators (mainly blue marlin, {M}akaira nigricans) present in 10% of daytime periods. {A} smaller sub-surface aggregation comprised of medium tuna mixed with "extranatants" (fishes which remain within 10 to 50 m of a {FAD}) was observed in 75% of night-time periods, whereas unidentified scattered fishes were detected from 70 to 400 m depth. {T}he low daytime vulnerability of medium sub-surface tunas to applied line techniques leads us to assume that their feeding motivation was low during daytime. {T}hese tunas could preferentially feed on mesopelagic organisms during night-time and transition periods around {M}artinican moored {FAD}s. {L}ocal fishermen mainly targeted the large scattered predators using very small tunas as living bait. {T}he sub-surface tuna aggregation hence appeared to be currently unexploited by local fisheries, though it represented the large majority of the pelagic biomass around the moored {FAD}s.},
  keywords = {},
  booktitle = {},
  journal = {{A}quatic {L}iving {R}esources},
  volume = {20},
  numero = {4},
  pages = {357--366},
  ISSN = {0990-7440},
  year = {2007},
  DOI = {10.1051/alr:2008004},
  URL = {https://www.documentation.ird.fr/hor/fdi:010040970},
}