ASSESSMENT OF THE LEVEL OF SURFACE ACTIVITY IN HUMPBACK WHALES DURING THE BREEDING SEASON

摘要: Between 1991 and 2002, the reproductive behavior of humpback whale was studied during breeding season off coast Ecuador, South America (02°S, 81°W). During sighting period level surface activity exhibited by whales assessed according to type display performed its frequency. Five displays that produce percussion sounds used likely for communication were considered: breaching, head-lapping, tail-slapping, flipper-slapping tail slashing. A total 289 selected sightings included in one four levels a scale intensity designed purpose. To determine what social conditions increased or reduced activity, groups organized their size age-class composition. Singletons three showed significantly higher than pairs larger highest (P<0.05). Differences also found when age-classes compared, with subadults showing other classes (P<0.01). Groups members significant difference respect decreasing at lowest Competitive occurrence 2 No relationship between speed activity. The possible influence environment factors such as day hour, sea state, moon phase 'El Nino', assessed; none which clear trend affect discussion about implications these findings is provided well interpretations meanings some under different contexts. This analysis indicates aspects rather drive season.