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Historical catch series for Antarctic and pygmy blue whales

Authors:
  • ATLANTNIRO,ECAT-KALININGRAD formerly

Abstract and Figures

Worldwide catch series are presented for blue whales during the modern whaling period (1868-1878), divided into five populations. There are only a handful of documented catches of blue whales prior to this period, and none afterwards. The data come from the IWC summary annual catch database and the IWC individual whale catch database, and correct for Soviet misreporting of blue whale catches in the late 1950s to early 1970s. Greatest emphasis is placed on obtaining updated catch series for Antarctic and pygmy blue whales, splitting them according to recent estimates of the proportion of each subspecies in different areas of the Southern Hemisphere and northern Indian Ocean. The total worldwide catches of blue whales were 382,595, of which 90.4% were Antarctic blue whales (345,775), 3.4% were pygmy blue whales (13,022), 1.4% were from the South-east Pacific (5,383), 2.1% were from the North Pacific (7,973) and 2.7% from the North Atlantic (10,442). These catch series are preliminary and no adjustment is made for struck and lost whales, except for a small fraction of the total that were reported to the IWC.
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... Until the start of industrial whaling, there had been no widespread whaling of either blue whales or fin whales B. physalus, but steampowered catcher vessels and explosive harpoons made catching these species possible. In the Southern Hemisphere and the northern Indian Ocean, 345 775 Antarctic blue whales B. m. intermedia and 13 022 pygmy blue whales B. m. brevicauda were killed between 1904 and 1973 (Branch et al. 2008). In the years between 1921 and 1935, blue whales were the main species caught in the Southern Hemisphere (except for 1925), with a peak of 30 406 blue whales killed in the 1930/1931 austral summer season (Branch et al. 2008). ...
... In the Southern Hemisphere and the northern Indian Ocean, 345 775 Antarctic blue whales B. m. intermedia and 13 022 pygmy blue whales B. m. brevicauda were killed between 1904 and 1973 (Branch et al. 2008). In the years between 1921 and 1935, blue whales were the main species caught in the Southern Hemisphere (except for 1925), with a peak of 30 406 blue whales killed in the 1930/1931 austral summer season (Branch et al. 2008). At South Georgia, blue whales were present year-round, and catches were reported in every month of the year (Branch et al. 2007b). ...
... In addition, a single Antarctic minke was caught, and 43 catches did not specify the species were no longer the primary target species (Clapham et al. 2008, Rocha et al. 2014). However, exploitation continued opportunistically whenever blue whales were encountered whilst hunting for fin whales and other species, continuing the drive towards extinction (Branch et al. 2013). Fewer than 1800 of the total catch of 42 698 blue whales at South Georgia be tween the 1904/1905 and 1970/1971 seasons were taken after the 1936/1937 season (Fig. 1). ...
... Until the start of industrial whaling, there had been no widespread whaling of either blue whales or fin whales B. physalus, but steampowered catcher vessels and explosive harpoons made catching these species possible. In the Southern Hemisphere and the northern Indian Ocean, 345 775 Antarctic blue whales B. m. intermedia and 13 022 pygmy blue whales B. m. brevicauda were killed between 1904 and 1973 (Branch et al. 2008). In the years between 1921 and 1935, blue whales were the main species caught in the Southern Hemisphere (except for 1925), with a peak of 30 406 blue whales killed in the 1930/1931 austral summer season (Branch et al. 2008). ...
... In the Southern Hemisphere and the northern Indian Ocean, 345 775 Antarctic blue whales B. m. intermedia and 13 022 pygmy blue whales B. m. brevicauda were killed between 1904 and 1973 (Branch et al. 2008). In the years between 1921 and 1935, blue whales were the main species caught in the Southern Hemisphere (except for 1925), with a peak of 30 406 blue whales killed in the 1930/1931 austral summer season (Branch et al. 2008). At South Georgia, blue whales were present year-round, and catches were reported in every month of the year (Branch et al. 2007b). ...
... In addition, a single Antarctic minke was caught, and 43 catches did not specify the species were no longer the primary target species (Clapham et al. 2008, Rocha et al. 2014). However, exploitation continued opportunistically whenever blue whales were encountered whilst hunting for fin whales and other species, continuing the drive towards extinction (Branch et al. 2013). Fewer than 1800 of the total catch of 42 698 blue whales at South Georgia be tween the 1904/1905 and 1970/1971 seasons were taken after the 1936/1937 season (Fig. 1). ...
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Thesis
La baleine bleue (Balaenoptera musculus ssp) a été menée au bord de l’extinction durant la chasse baleinière et est aujourd’hui toujours en danger. Dans l’océan Indien austral, une région reculée et soumise à des conditions météorologiques extrêmes, l’utilisation de l’acoustique passive s’est rapidement imposée pour le suivi de ces grands mammifères marins. Cette thèse repose sur des enregistrements acoustiques acquis de 2010 à 2018 par un réseau d’hydrophones de grande envergure situé dans l’océan Indien austral. Un algorithme de détection automatique, dont les performances sont préalablement évaluées, est appliqué pour détecter les vocalisations stéréotypées et non-stéréoptyées (D-calls) des baleines bleues Antarctique et des baleines bleues pygmées d’Australie et de Madagascar. Les détections des vocalisations stéréotypées précisent les distributions spatiales et saisonnières décrites précédemment dans l'océan Indien austral et révèlent que les baleines bleues Antarctique et pygmées habitent cette région de façon très différente. La comparaison entre la présence géographique des vocalisations stéréotypées et non-stéréotypées suggère un changement de comportement acoustique des baleines bleues entre les régions subtropicales et subantarctiques. Enfin, la caractérisation du paysage sonore dans l’océan Indien austral indique que les signaux d'origine anthropique y sont prévalents, y compris dans les régions les plus reculées.
... Despite years of commercial exploitation, blue whale populations are still found in all major oceans, but the current size of most populations is estimated to be a fraction of preexploitation levels [14,25]. By 1966 the International Whaling Commission (IWC) had banned the killing of blue whales worldwide. ...
... Despite years of commercial exploitation, blue whale populations are still found in all major oceans, but the current size of most populations is estimated to be a fraction of preexploitation levels [14,25]. By 1966 the International Whaling Commission (IWC) had banned the killing of blue whales worldwide. ...
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