@inproceedings{fdi:010085796,
  title = {{T}emporal trends and variability in the spatial distribution of {E}uropean tropical tuna purse-seine fishing in the {A}tlantic and {I}ndian {O}ceans},
  author = {{K}aplan, {D}avid and {B}aez, {J}.{C}. and {A}layon, {P}.{J}.{P}. and {V}idal, {T}.},
  editor = {},
  language = {{ENG}},
  abstract = {{I}t is useful to complement more sophisticated stock status estimations based on stock assessment models with simpler approaches based on analyses of raw catch-effort data to maximize the probability of detecting overexploitation and hyperstability as early as possible. {H}ere we develop a series of annual indices for the spatial distribution of catch over 1991-2019 by {E}uropean purse seine vessels of the three major tropical tuna species as a function of ocean and fishing mode (floating object or free swimming fish schools). {T}ime series of these indices are examined to identify temporal patterns with a focus on any long term trends that might be indicative of declining stock status or hyperstability. {S}patial indices are also calculated for important bycatch species over 2011-2019 from observer data for {F}rench vessels. {I}n general, results indicate a relative stability in the spatial distribution of catch over the last 30 years, though major perturbations, such as {S}omali piracy and major {E}l {N}iño events, are identifiable. {N}evertheless, recent decreasing trends in the presence of bigeye tuna and certain bycatch species merit further investigation.},
  keywords = {{ATLANTIQUE} ; {OCEAN} {INDIEN}},
  numero = {{IOTC}-2021-{WPTT}23-20_{R}ev1},
  pages = {37  multigr.},
  booktitle = {23{\`e}me groupe de travail sur les thons tropicaux},
  year = {2021},
  URL = {https://www.documentation.ird.fr/hor/fdi:010085796},
}