First evidence of bubble‐net feeding and the formation of ‘super‐groups’ by the east Australian population of humpback whales during their southward migration

2021 ◽  
Author(s):  
Vanessa Pirotta ◽  
Kylie Owen ◽  
David Donnelly ◽  
Madeleine J. Brasier ◽  
Robert Harcourt
Keyword(s):  
Humpback Whales ◽  
Australian Population ◽  
Southward Migration

Aerial Observations on the Humpback Whale, Megaptera nodosa (Bonnaterre), with Notes on Other Species

1953 ◽  
Vol 4 (2) ◽  
pp. 219 ◽  
Author(s):  
RG Chittleborough
Keyword(s):  
Western Australia ◽  
Great Increase ◽  
Humpback Whale ◽  
Mean Value ◽  
Humpback Whales ◽  
Maximum Frequency ◽  
Minke Whales ◽  
The Mean ◽  
Exmouth Gulf ◽  
Southward Migration

Aerial observations of humpback whales in the region of Point Cloates, Western Australia, during 1952 are recorded. The first southward-moving humpback whale was sighted on July 21, while decreasing numbers were seen moving northwards until early October. In 1952 the change from a predominantly northward migration of humpback whales to a southward migration occurred close to August 24. The speed of migration of a number of these whales is recorded, the mean value being 4.3 kt. A few humpback whale calves were sighted early in July and a peak in their occurrence in August suggests maximum frequency of parturition early in August. A very great increase in the occurrence of calves in the area late in the season suggests that female humpback whales rearing calves move southwards later than other individuals. Some evidence is presented that Exmouth Gulf is a nursery area. The presence of some killer, fin, blue, and minke whales in the area is noted.

scholarly journals Cultural revolutions reduce complexity in the songs of humpback whales

2018 ◽  
Vol 285 (1891) ◽  
pp. 20182088 ◽  
Author(s):  
Jenny A. Allen ◽  
Ellen C. Garland ◽  
Rebecca A. Dunlop ◽  
Michael J. Noad
Keyword(s):  
Vocal Learning ◽  
Humpback Whales ◽  
Australian Population ◽  
Learning Capacity ◽  
The Social ◽  
Novel Material ◽  
Entire Sequence ◽  
Structure Complexity ◽  
Entropy Estimates

Much evidence for non-human culture comes from vocally learned displays, such as the vocal dialects and song displays of birds and cetaceans. While many oscine birds use song complexity to assess male fitness, the role of complexity in humpback whale ( Megaptera novaeangliae ) song is uncertain owing to population-wide conformity to one song pattern. Although songs change gradually each year, the eastern Australian population also completely replaces their song every few years in cultural ‘revolutions’. Revolutions involve learning large amounts of novel material introduced from the Western Australian population. We examined two measures of song structure, complexity and entropy, in the eastern Australian population over 13 consecutive years. These measures aimed to identify the role of complexity and information content in the vocal learning processes of humpback whales. Complexity was quantified at two hierarchical levels: the entire sequence of individual sound ‘units’ and the stereotyped arrangements of units which comprise a ‘theme’. Complexity increased as songs evolved over time but decreased when revolutions occurred. No correlation between complexity and entropy estimates suggests that changes to complexity may represent embellishment to the song which could allow males to stand out amidst population-wide conformity. The consistent reduction in complexity during song revolutions suggests a potential limit to the social learning capacity of novel material in humpback whales.

Modeling cetacean habitat use in an urban coastal area in southeastern Brazil

2020 ◽  
Vol 642 ◽  
pp. 227-240
Author(s):  
L Lodi ◽  
R Tardin ◽  
G Maricato
Keyword(s):  
Habitat Use ◽  
Protected Areas ◽  
Linear Models ◽  
Anthropogenic Activities ◽  
Buffer Zone ◽  
Humpback Whales ◽  
Southeastern Brazil ◽  
Major Influence ◽  
Cetacean Species ◽  
Few Data

Most studies of cetacean habitat use do not consider the influence of anthropogenic activities. We investigated the influence of environmental and anthropogenic variables on habitat use by humpback Megaptera novaeangliae and Bryde’s whales Balaenoptera brydei off the coast of the Brazilian city of Rio de Janeiro. Although there are 2 marine protected areas (MPAs) in this area, few data are available on cetacean habitat use or on the overlap of different cetacean species within these MPAs. Our aim was to evaluate the effectiveness of the MPAs and propose a buffer zone to better protect the biodiversity of the study area. We conducted systematic surveys and developed spatial eigenvector generalized linear models to characterize habitat use by the species in the study area. Habitat use by humpback whales was influenced only by depth, whereas for Bryde’s whales there was the additional influence of anthropogenic variables. For Bryde’s whales, which use the area for feeding, sea surface temperature and the distance to anchorages had a major influence on habitat use. We also showed that neither of the MPAs in the study area adequately protects the hotspots of either whale species. Most of the humpback whale grid cells with high sighting predictions were located within 2 km of the MPAs, while areas of high sighting prediction of Bryde’s whales were located up to 5 km from the MPAs, closer to beaches. Our findings provide important insights for the delimitation of protected areas and zoning of the MPAs.

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