Low latitude habitat use patterns of a recovering population of humpback whales
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Data
2018-08-01
Autores
Carvalho Goncalves, Maria Isabel
De Sousa-Lima, Renata Santoro
Teixeira, Niel Nascimento
Morete, Maria Emilia
De Carvalho, Gustavo Henrique [UNESP]
Ferreira, Harildon Machado
Baumgarten, Julio Ernesto
Título da Revista
ISSN da Revista
Título de Volume
Editor
Cambridge Univ Press
Resumo
The coast of Brazil is an important low latitude nursery ground for humpback whales (Megaptera novaeangliae). The number of humpback whales in this region has increased and its population is reoccupying areas where it has been depleted during the whaling period. The goal of this study was to conduct land-based observations during 2014 and 2015 to characterize patterns of habitat use and relative abundance of humpback whales that migrate to one of these reoccupation areas: Serra Grande, Bahia state. The observed mean group size was 2.12 +/- 0.96 individuals and did not vary through the reproductive season nor between years. Dyads (32.9%) and singletons (26.7%) were more frequently observed, and groups with calves represented 21.2% of the sightings. The mean number of whales counted per hour increased from 2014 (3.44 +/- 3.35) to 2015 (5.12 +/- 4.18). Habitat use varied during the season; whales used shallower waters closer to shore as the season progressed. The spatial distribution of groups with calves was dependent on the presence and number of escorts. Spatial segregation of groups with calves closer to shore is a key factor in understanding the overall distribution of whales in the area, suggesting that social strategies are affected by environmental factors, as seen in other wintering grounds. Small-scale studies from land-based stations, in areas such as this where there is no previous knowledge about the species, are cost effective. They provide information about the overall behavioural and spatial patterns while anthropogenic activity is still low, allowing habitat protection and management decisions before implementation and increase of human activities.
Descrição
Palavras-chave
Humpback whale, land-based observation station, habitat use, distribution, depth, occurrence
Como citar
Journal Of The Marine Biological Association Of The United Kingdom. New York: Cambridge Univ Press, v. 98, n. 5, p. 1087-1096, 2018.