@article{fdi:010057271,
  title = {{P}elagic longline fishing trials to shape a mitigation device of the depredation by toothed whales},
  author = {{R}abearisoa, {N}jaratiana and {B}ach, {P}ascal and {T}ixier, {P}. and {G}uinet, {C}.},
  editor = {},
  language = {{ENG}},
  abstract = {{D}epredation is defined as the damage or removal of fish from fishing gear by predators, and is a crucial issue leading to negative impacts on both animals involved in depredation and fisheries. {D}epredation in longline pelagic fisheries targeting swordfish ({X}iphias gladius) and tuna ({T}hunnus spp.) involves short-finned pilot whales ({G}lobicephala macrorhynchus), false killer whales ({P}seudorca crassidens) and some pelagic sharks. {S}ince no long-term solution could be found to date, we investigated fishing gear improvement by deploying a technology designed to physically protect the hooked fish by hiding it to predators: the {DMD} (depredation mitigation device). {T}wo types of {DMD}s were designed: "spiders" and "socks". {T}he efficiency of "spiders" was tested in {N}ovember 2007 during a fishing trial of 26 longline fishing operations when 12,480 hooks and 1970 devices were set. {T}he efficiency of "socks" was tested in {O}ctober 2008 during a fishing trial of 32 longline fishing operations when 13,220 hooks and 339 devices were set. 117 and 24 fish were hooked on branchlines equipped with spiders and socks, respectively and among those devices, 87.3% versus 69.2% were correctly triggered and 80% versus 15% of the fish were correctly protected. {A} low entanglement rate of the spiders with the fishing gear was found (3.6%), but a higher one was associated to the socks (17.8%). {O}perational constraints to routinely deploy "spiders" were examined. {T}he number of sets impacted by shark depredation was significantly greater than the number of sets involving toothed whale depredation. {H}owever, when depredation occurred, the proportion of fish damaged by toothed whales was significantly greater. {W}hile more trials should be carried out to deeply verify the efficiency of {DMD}s, we remain convinced that considerations of fishing gear technologies might be more actively investigated to propose innovative measures to mitigate toothed whale depredation in pelagic longlining. {F}or this type of gear, innovative technology is an important issue of the ecosystem approach to fisheries ({EAF}) framework.},
  keywords = {{F}ishery interaction ; {G}lobicephala macrorhynchus ; {P}hysical protection ; {P}seudorca crassidens ; {S}ock design ; {S}pider design},
  booktitle = {},
  journal = {{J}ournal of {E}xperimental {M}arine {B}iology and {E}cology},
  volume = {432},
  numero = {},
  pages = {55--63},
  ISSN = {0022-0981},
  year = {2012},
  DOI = {10.1016/j.jembe.2012.07.004},
  URL = {https://www.documentation.ird.fr/hor/fdi:010057271},
}