Cetacean strandings on the coast of Ceará, north-eastern Brazil (1992–2005)

Abstract

This study reviews and updates information on cetacean strandings in the state of Ceará, Brazil (02°30′S 41°15′W– 04°30′S 36°45′W), comprising 573 km of coastline. In the years 1992–2005, there were 252 cetacean stranding events, representing 19 species: three species of Balaenopteridae, three Physeteridae, two Kogiidae, two Ziphiidae and 11 Delphinidae. Three species comprised the majority (78.9%) of stranding events: estuarine dolphin,Sotalia guianensis(61.9%); sperm whale,Physeter macrocephalus(10.3%); and rough-toothed dolphin,Steno bredanensis(6.7%). There was an increasing trend in the number of cases reported in the first five years with a highest frequency achieved in 1996. Stranding events occurred throughout the year, with the lowest frequency occurring in the autumn (March–May). Approximately 4% of the events were attributed to natural causes while 24.6% were human-related, mainly incidental captures. Meat removal for human consumption or bait was recorded in 6.7% of events. In the study area,Sotalia guianensis,P. macrocephalusandSteno bredanensiswere the most abundant cetacean species, whereasLagenodelphis hosei,Pseudorca crassidens,Orcinus orca,Kogia sima,Mesoplodon europaeus,Balaenoptera acutorostrataandBalaenoptera bonaerensisare probably rare in the area.