Rough-Toothed Dolphins (Steno bredanensis) Catch Diskfishes while Interacting with Humpback Whales (Megaptera novaeangliae) off Abrolhos Bank Breeding Ground, Southwest Atlantic

2004 ◽  
Vol 30 (2) ◽  
pp. 327-329 ◽  
Author(s):  
Leonardo L. Wedekin ◽  
Ana Freitas ◽  
Márcia H. Engel ◽  
Ivan Sazima
2006 ◽  
Vol 313 ◽  
pp. 295-304 ◽  
Author(s):  
AN Zerbini ◽  
A Andriolo ◽  
MP Heide-Jørgensen ◽  
JL Pizzorno ◽  
YG Maia ◽  
...  

2008 ◽  
Vol 65 (4) ◽  
pp. 667-673 ◽  
Author(s):  
Marcos R. Rossi-Santos ◽  
Elitieri S. Neto ◽  
Clarêncio G. Baracho ◽  
Sérgio R. Cipolotti ◽  
Enrico Marcovaldi ◽  
...  

Abstract Rossi-Santos, M. R., Neto, E. S., Baracho, C. G., Cipolotti, S. R., Marcovaldi, E., and Engel, M. H. 2008. Occurrence and distribution of humpback whales (Megaptera novaeangliae) on the north coast of the State of Bahia, Brazil, 2000–2006. – ICES Journal of Marine Science, 65: 667–673. The Abrolhos Bank off Brazil is considered the main breeding ground for the humpback whale (Megaptera novaeangliae) in the Southwest Atlantic. However, owing to an increase in the occurrence of the species along the north coast of the State of Bahia, it has been suggested that the species is reoccupying that region, which was probably utilized by the whales before commercial whaling. Information is presented on the occurrence and distribution of humpback whales along the north coast of the State of Bahia, with a comparative overview, for the period 2000–2006. Daily research cruises were conducted from July to October, departing from Praia do Forte (13°40′S 38°10′W) and lasting ∼9 h. Data on sampling and sighting effort, and geographical position and composition of groups of humpback whales, were collected on standardized field sheets. In all, 230 surveys were performed, covering some 9740 nautical miles in 1645 h of sampling effort, during which 1626 humpback whales were sighted, including 118 calves. Humpback whales were sighted throughout the study area. Solitary individuals and pairs were the most frequent group composition, 26% and 37% of the observed groups (n = 723), respectively. Depth of water varied from 15 to 1657 m (mean = 62.4; s.d. = 99). The sightings values were grouped into depth classes to ascertain the highest frequencies (∼30%) for the two classes, i.e. between 35.1 and 55 m of water. There was an increase in the encounter rates of humpback whales on the north coast of the State of Bahia between 2000 and 2006, identifying a difference in SPUE [sightings per unit (h) of effort] among years (Kruskal–Wallis H = 30.155, d.f. = 6, p < 0.05). The results support the hypothesis that humpback whales are reoccupying former breeding areas along the Brazilian coast.


2012 ◽  
Vol 101 (2) ◽  
pp. 145-158 ◽  
Author(s):  
KR Groch ◽  
MCC Marcondes ◽  
AC Colosio ◽  
JL Catão-Dias

1995 ◽  
Vol 73 (7) ◽  
pp. 1290-1299 ◽  
Author(s):  
Peter J. Corkeron

The effects of the presence of vessels on the behaviour of humpback whales (Megaptera novaeangliae) was studied in Hervey Bay, Queensland, where southward-migrating whales are the focus of a commercial whale-watching industry. The behaviour of whales was observed from a small yacht under sail. Rates of occurrence of units of behaviour for entire pods were obtained from continuous sampling of pods. Pods without calves showed lower rates of behaviour generally when vessels were within 300 m of them. Pods both with and without calves were more likely to dive rather than slip under when vessels were within 300 m. Hybrid multidimensional scaling of rates of behaviours of pods indicated differences between suites of behaviours exhibited by pods when vessels were within 300 m of them and when they were not. Classification of the patterns of occurrence of behaviours demonstrated that for pods both with and without calves, different units of behaviour tended to occur together when vessels were within 300 m and when they were not. Whale watching offers a nonlethal commercial use of whales, but in Hervey Bay, whale watching affects the behaviour of whales, which, although migrating, can be involved in breeding ground activities. Whether the short-term behavioural changes described here are accompanied by longer term avoidance of Hervey Bay by humpback whales as they migrate south remains to be determined.


10.5597/00251 ◽  
2019 ◽  
Vol 14 (1) ◽  
pp. 27-33
Author(s):  
Astrid Frisch-Jordán ◽  
Nicola Ransome ◽  
Oscar Aranda-Mena ◽  
Fernando Romo-Sirvent

Banderas Bay, located in the Mexican Pacific, is a breeding/calving ground for the North Pacific stock of humpback whales (Megaptera novaeangliae) during the winter.  While sporadic registers of humpback whales feeding on their mating grounds exist, this is the first occasion where feeding activity was observed intensively and extensively on a breeding ground.  Between 19 December 2011 and 6 March 2012, 26 such occurrences were registered in Banderas Bay, along the mainland pacific coast.  On five occasions, groups of 20 or more individuals were recorded feeding. They were feeding over and under the surface using lunging and gulping techniques.  On several occasions humpbacks were observed feeding alongside Bryde´s whales (Balaenoptera edeni), Pantropical spotted dolphins (Stenella attenuata) and Bottlenose dolphins (Tursiops truncatus).  Two different samples of fish at two different feeding sites were taken and the fish identifications showed these were Pacific anchovies (Cetengraulis mysticetus).  Among the 26 sightings, nine different species of birds were registered feeding in the same area as the humpback whales.  The number of whales feeding over an extended period of time in their breeding ground could be an indicator that there was not enough food in their feeding grounds, but the possibility that they might just be taking advantage of good food availability is also possible.


2021 ◽  
Vol 19 (2) ◽  
pp. 131-147
Author(s):  
Charlotte D. Van Driessche ◽  
Nakia Cullain ◽  
Yara Tibiriçá ◽  
Ian O'Connor

Little is known about the humpback whales (Megaptera novaeangliae) of the East-African Coast genetic sub-unit (C1). With an estimated population size of 7000 whales, they demonstrate the resilience of the species after commercial whaling caused population numbers to decline drastically. Zavora Bay, Mozambique offers an ideal observation point of the passage of the whales during their annual migration towards the breeding ground of southern Africa and serves as an operating base to monitor this population. This study aimed at identifying the importance of Zavora Bay as part of this breeding ground and the core regions for humpback whale use within the study area. Results showed the waters off the coast of Zavora are actively used for breeding and do not merely serve as passage towards the wintering habitats. A mother-calf pair separation with a preference for shallower waters closer to shore was observed. Besides depth and distance to shore, slope also proved to have a significant influence on the distribution of adult humpback whales. Increased survey effort and more detailed investigation of the threats to humpback whales within the waters of Zavora are recommended.


2008 ◽  
Vol 124 (4) ◽  
pp. 2484-2484
Author(s):  
Alison K. Stimpert ◽  
Whitlow W. L. Au ◽  
David N. Wiley ◽  
David Mattila

2008 ◽  
Vol 88 (6) ◽  
pp. 1229-1235 ◽  
Author(s):  
Maria E. Morete ◽  
Tatiana L. Bisi ◽  
Richard M. Pace ◽  
Sergio Rosso

The humpback whale (Megaptera novaeangliae) population that uses Abrolhos Bank, off the east coast of Brazil as a breeding ground is increasing. To describe temporal changes in the relative abundance of humpback whales around Abrolhos, seven years (1998–2004) of whale count data were collected during July through to November. During one-hour-scans, observers determined group size within 9.3 km (5 n.m.) of a land-based observing station. A total of 930 scans, comprising 7996 sightings of adults and 2044 calves were analysed using generalized linear models that included variables for time of day, day of the season, years and two-way interactions as possible predictors. The pattern observed was the gradual build-up and decline in whale counts within seasons. Patterns and peaks of adult and calf counts varied among years. Although fluctuation was observed, there was generally an increasing trend in adult counts among years. Calf counts increased only in 2004. These fluctuations may have been caused by some environmental conditions in humpback whales' summering grounds and also by changes in spatial–temporal concentrations in Abrolhos Bank. The general pattern observed within the study area mirrored what was observed in the whole Abrolhos Bank. Knowledge of the consistency with which humpback whales use this important nursing area should prove beneficial for designing future monitoring programmes especially related to whale watching activities around Abrolhos Archipelago.


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