scholarly journals Whale distribution in a breeding area: spatial models of habitat use and abundance of western South Atlantic humpback whales

2017 ◽  
Vol 585 ◽  
pp. 213-227 ◽  
Author(s):  
GA Bortolotto ◽  
D Danilewicz ◽  
PS Hammond ◽  
L Thomas ◽  
AN Zerbini
Keyword(s):  
Habitat Use ◽  
Spatial Models ◽  
South Atlantic ◽  
Humpback Whales ◽  
Breeding Area

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.

scholarly journals Cetacean records along a coastal-offshore gradient in the Vitória-Trindade Chain, western South Atlantic Ocean

2014 ◽  
Vol 74 (1) ◽  
pp. 137-144 ◽  
Author(s):  
LL Wedekin ◽  
MR Rossi-Santos ◽  
C Baracho ◽  
AL Cypriano-Souza ◽  
PC Simões-Lopes
Keyword(s):  
Humpback Whale ◽  
South Atlantic ◽  
Breeding Habitat ◽  
Humpback Whales ◽  
Balaenoptera Physalus ◽  
Fin Whale ◽  
Antarctic Minke Whale ◽  
Trindade Island ◽  
The Antarctic ◽  
Species Being

Oceanic waters are difficult to assess, and there are many gaps in knowledge regarding cetacean occurrence. To fill some of these gaps, this article provides important cetacean records obtained in the winter of 2010 during a dedicated expedition to collect visual and acoustic information in the Vitória-Trindade seamounts. We observed 19 groups of cetaceans along a 1300-km search trajectory, with six species being identified: the humpback whale (Megaptera novaeangliae, N = 9 groups), the fin whale (Balaenoptera physalus, N = 1), the Antarctic minke whale (Balaenoptera bonaerensis, N = 1), the rough-toothed dolphin (Steno bredanensis, N = 1), the bottlenose dolphin (Tursiops truncatus, N = 2), and the killer whale (Orcinus orca, N = 1). Most humpback whale groups (N = 7; 78%) were observed in the Vitória-Trindade seamounts, especially the mounts close to the Abrolhos Bank. Only one lone humpback whale was observed near Trindade Island after a search effort encompassing more than 520 km. From a total of 28 acoustic stations, humpback whale songs were only detected near the seamounts close to the Abrolhos Bank, where most groups of this species were visually detected (including a competitive group and groups with calves). The presence of humpback whales at the Trindade Island and surroundings is most likely occasional, with few sightings and low density. Finally, we observed a significant number of humpback whales along the seamounts close to the Abrolhos Bank, which may function as a breeding habitat for this species. We also added important records regarding the occurrence of cetaceans in these mounts and in the Western South Atlantic, including the endangered fin whale.

Age-specific behavior and habitat use in humpback whales: Implications for vessel strike

2021 ◽  
Author(s):  
JEF Stepanuk ◽  
EI Heywood ◽  
JF Lopez ◽  
RA DiGiovanni Jr ◽  
LH Thorne
Keyword(s):  
Habitat Use ◽  
Humpback Whales ◽  
Specific Behavior

Behavioural reactions of wintering humpback whales (Megaptera novaeangliae) to biopsy sampling in the western South Atlantic

2010 ◽  
Vol 90 (8) ◽  
pp. 1701-1711 ◽  
Author(s):  
Mauricio Cantor ◽  
Taiana Cachuba ◽  
Luena Fernandes ◽  
Márcia H. Engel
Keyword(s):  
Mating Behaviour ◽  
South Atlantic ◽  
Humpback Whales ◽  
Long Term Effects ◽  
Conservation Policies ◽  
Breeding Grounds ◽  
Lactating Females ◽  
Access Information ◽  
Large Groups

Molecular analysis has become a powerful tool in cetacean ecology since it supports efficient conservation policies. Remote biopsy sampling is the most efficient method to obtain epithelial material for analysis purposes; however, as an intrusive technique it presents inherent costs, evidenced by behavioural reactions. Clarifying which factors influence these responses is essential to assess its impact and prevent possible long-term effects. For eleven winters, samples from humpback whales were collected in the Abrolhos Bank, the main breeding ground of this species in the western South Atlantic. We analysed the influence of several characteristics of the shot, vessels, groups and behaviour on the frequency and intensity of the whales' response. The majority of biopsied whales did not show any detectable response. Among those that responded, a low-level category of reaction was most frequent. The use of larger boats resulted in less intense responses. Responses were influenced by group size and behavioural state: large groups, which were involved in aggressive mating behaviour, reacted less frequently than smaller groups. Females with calves showed less intense reactions than non-lactating females. The behaviour of the animals prior to and during the boat approach also affected their response: resting whales responded more intensely than whales involved in social or travel activities. Comparison with previous studies confirmed that reactions vary in intensity according to location: whales biopsied in feeding grounds responded with more intensity than those in breeding grounds, which in turn responded more intensely than whales in migration. This study reinforces existing evidence that biopsy sampling is unlikely to have long-term effects and can thus continue to be used as one of the main tools to access information which is vital for conservation.

scholarly journals Low latitude habitat use patterns of a recovering population of humpback whales

2018 ◽  
Vol 98 (5) ◽  
pp. 1087-1096 ◽  
Author(s):  
Maria Isabel Carvalho Gonçalves ◽  
Renata Santoro De Sousa-Lima ◽  
Niel Nascimento Teixeira ◽  
Maria Emilia Morete ◽  
Gustavo Henrique De Carvalho ◽  
...  
Keyword(s):  
Habitat Use ◽  
Cost Effective ◽  
Humpback Whales ◽  
Anthropogenic Activity ◽  
Small Scale ◽  
Nursery Ground ◽  
Social Strategies ◽  
Low Latitude ◽  
Use Patterns ◽  
Key Factor

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.

New Evidence for a South Atlantic Stock of Humpback Whales Wintering on the Northwest African Continental Shelf

2013 ◽  
Vol 48 (1) ◽  
pp. 177-186 ◽  
Author(s):  
Koen Van Waerebeek ◽  
Abdoulaye Djiba ◽  
Jens-Otto Krakstad ◽  
Abdellahi Samba Ould Bilal ◽  
Idrissa L. Bamy ◽  
...  
Keyword(s):  
Continental Shelf ◽  
South Atlantic ◽  
Humpback Whales ◽  
New Evidence

Long-Range Movement of Humpback Whales and Their Overlap with Anthropogenic Activity in the South Atlantic Ocean

2014 ◽  
Vol 28 (2) ◽  
pp. 604-615 ◽  
Author(s):  
HOWARD C. ROSENBAUM ◽  
SARA M. MAXWELL ◽  
FRANCINE KERSHAW ◽  
BRUCE MATE
Keyword(s):  
Atlantic Ocean ◽  
Long Range ◽  
South Atlantic ◽  
South Atlantic Ocean ◽  
Humpback Whales ◽  
Anthropogenic Activity ◽  
The South
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