THE NORTHEASTERN ALBORAN SEA, AN IMPORTANT BREEDING AND FEEDING GROUND FOR THE LONG-FINNED PILOT WHALE (GLOBICEPHALA MELAS) IN THE MEDITERRANEAN SEA

Authors

  • Ana Cañadas,

    1. ALNITAK Marine Environment Research and Education Center, Nalón 16, 28240 Hoyo de Manzanares, Madrid, Spain, and Grupo de Investigación de Cetáceos, Laboratory of Archaeozoology, Department of Zoology, Universidad Autónoma de Madrid Ctra. Colmenar Viejo, Km. 15, Cantoblanco 28049, Madrid, Spain E-mail: alnitak@cetaceos.com
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  • Ricardo Sagarminaga

    1. ALNITAK Marine Environment Research and Education Center, Nalón 16, 28240 Hoyo de Manzanares, Madrid, Spain
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Abstract

Little is known about the long-finned pilot whale's population size, structure, distribution, and dynamics in the Western Mediterranean basin. The research region covered since 1992 in southeast Spain, at the edge of the Alboran Sea, is considered an important oceanographic transition zone between the Mediterranean and the Atlantic Ocean. The research ship Toftevaag carried out surveys covering a total of 10,173 nmi (18,840 km) from April to September each year, 1992-1997, all years pooled. Effort for ten-by-ten-mile quadrants was stratified by depth and sea state to ascertain encounter rates. Tracking was used together with photo-identification of animals to analyze home range of groups. Behavior was recorded ad libitum, and underwater video taping was used to analyze specific behavior patterns. One hundred and nine sightings of pilot whales were made. The average group size was 41.4 ± 58.4, ranging from 1 to 350. The average depth at encounters was 848.7 ± 281.2 m ranging from 300 to 1,800 m. Compatison of results for encounter rate and group size with those for other Mediterranean regions, together with site fidelity shown by photo-identification and observations of reproductive behavior, reflect the importance of the Alboran Sea to the species in the Mediterranean.

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