scholarly journals Changing patterns of habitat use by southern right whales (Eubalaena australis) on their nursery ground at Península Valdés, Argentina, and in their long-range movements

2020 ◽  
pp. 133-143
Author(s):  
Victoria J. Rowntree ◽  
Roger S. Payne ◽  
Donald M. Schell
Keyword(s):  
Habitat Use ◽  
Nitrogen Isotope ◽  
Isotope Ratios ◽  
Small Scale ◽  
Nursery Ground ◽  
Adult Males ◽  
Human Disturbances ◽  
Eubalaena Australis ◽  
Right Whales ◽  
Southern Right Whales

Southern right whales (Eubalaena australis) have been studied on their nursery ground at Península Valdés, Argentina, every year since 1970. Since 1990, 1,208 individuals have been identified from photographs taken during annual aerial surveys; 618 whales were seen in two or more years. Patterns of habitat use have changed during the study in ways which suggest that right whales may be capable of substantial behavioral and ecological flexibility. One male and three females from Península Valdés have been sighted on other nursery grounds (Tristan da Cunha and southern Brazil). Three individuals from Península Valdés were sighted on feeding grounds off Shag Rocks and South Georgia. Some right whales from Península Valdés showed carbon and nitrogen isotope ratios very similar to those seen in right whales off South Africa, while others showed distinctive isotope ratios indicating that they fed in a different area. Whales of all ages and both sexes moved frequently between three major regions of concentration on the Península Valdés nursery ground. Subadults and adult females with calves were resighted at higher rates than adult males and females in non-calf years. Changes in the geographic distribution of whales at the Península include: (1) abandonment of a major region of concentration; (2) establishment of a nursery area adjacent to thecentre of a growing whalewatching industry; and (3) small-scale shifts in distribution, possibly in response to natural and human disturbances.

Southern right whales ( Eubalaena australis ) return to a former wintering calving ground: Fowlers Bay, South Australia

2019 ◽  
Vol 35 (4) ◽  
pp. 1438-1462
Author(s):  
Claire Charlton ◽  
Rhianne Ward ◽  
Robert D. McCauley ◽  
Robert L. Brownell ◽  
Sacha Guggenheimer ◽  
...  
Keyword(s):  
South Australia ◽  
Eubalaena Australis ◽  
Right Whales ◽  
Southern Right Whales

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.

scholarly journals Wood Thrush Movements and Habitat Use: Effects of Forest Management for Red-Cockaded Woodpeckers

The Auk ◽  
2002 ◽  
Vol 119 (1) ◽  
pp. 109-124 ◽  
Author(s):  
Jason D. Lang ◽  
Larkin A. Powell ◽  
David G. Krementz ◽  
Michael J. Conroy
Keyword(s):  
Habitat Use ◽  
Pinus Taeda ◽  
Loblolly Pine ◽  
Small Scale ◽  
Picoides Borealis ◽  
Adult Males ◽  
Hylocichla Mustelina ◽  
Wood Thrush ◽  
Dispersal Distances ◽  
Wood Thrushes

Abstract We monitored adult and juvenile breeding-season movements and habitat use of radio-tagged Wood Thrushes (Hylocichla mustelina) at the Piedmont National Wildlife Refuge, central Georgia, USA. We investigated the effects that management for Red-cockaded Woodpeckers (Picoides borealis), thinning and burning >30 year old loblolly pine (Pinus taeda) habitat, had on Wood Thrushes, a ground-foraging and midstory-nesting species. Adult Wood Thrush pairs regularly moved long distances between nesting attempts (range 1 to 17,388 m). The only experimental effect we found on adult movements was a decrease in weekly emigration rates (Ψ) from thinned and burned compartments after silvicultural management. Adult males preferred riparian hardwoods with sparse to moderate cover and those preferences increased following management. Juveniles remained near their nest site (x̄ = 177 m, SE = 113) for an average 24 days (SE = 6.3), and then dispersed a mean 2,189 m (SE = 342). Before dispersal, juveniles preferred upland hardwood–pine mixed habitat (P < 0.05) with moderate overstory cover (P < 0.05). We found no management effects on dispersal distances or predispersal habitat use. However, juveniles from thinned and burned compartments dispersed to hardwood habitats with dense cover, whereas birds from control compartments dispersed to pine-dominated habitats with sparse cover. All juveniles dispersed to areas with habitat similar to what they used before dispersal. Small-scale thinning and burning for Red-cockaded Woodpeckers may have had little effect on Wood Thrush habitat use and movements because typical movements were often larger than the scale (stand or compartment) targeted for management.

scholarly journals Domoic acid in a marine pelagic food web: Exposure of southern right whales Eubalaena australis to domoic acid on the Península Valdés calving ground, Argentina

Harmful Algae ◽  
2017 ◽  
Vol 68 ◽  
pp. 248-257 ◽  
Author(s):  
Valeria C. D’Agostino ◽  
Mariana Degrati ◽  
Viviana Sastre ◽  
Norma Santinelli ◽  
Bernd Krock ◽  
...  
Keyword(s):  
Food Web ◽  
Domoic Acid ◽  
Eubalaena Australis ◽  
Pelagic Food Web ◽  
Right Whales ◽  
Southern Right Whales

scholarly journals Stranding events of southern right whales, Eubalaena australis, in southern Brazil

2020 ◽  
pp. 157-160
Author(s):  
Antonio B. Greig ◽  
Eduardo R. Secchi ◽  
Alexandre N. Zerbini ◽  
Luciano Dalla Rosa
Keyword(s):  
Storm Surges ◽  
Anthropogenic Factors ◽  
Brazilian Coast ◽  
Illegal Hunting ◽  
Right Whale ◽  
Eubalaena Australis ◽  
Marine Traffic ◽  
Right Whales ◽  
Southern Right Whales ◽  
The Right

Although international protection has been granted since 1935, southern right whales have only recently shown signs of recovery, possiblydue to anthropogenic factors. Off Brazil, illegal hunting of right whales occurred until 1973. This paper reports on surveys conducted alongthe southern Brazilian coast and the information recovered on right whale strandings for this area from 1977-1995. In the first 10 years ofthis period only four cases were registered. However, in contrast, 20 cases were counted during the last nine years. These results arediscussed in relation to marine traffic and the fisheries in the area that produce risks of collision and entanglement. Further, the possibilityof storm surges being a preponderant factor in the mortalities in this area is presented. These yearly rates are compared with neighbouringareas that are also inhabited by the right whales. Both possibilities fit the hypothesis that the right whales using the Brazilian coast forbreeding may finally be showing signs of recovery.

scholarly journals A note on an automated system for matching the callosity patterns on aerial photographs of southern right whales

2020 ◽  
pp. 291-295
Author(s):  
Lex Hiby ◽  
Phil Lovell
Keyword(s):  
Random Search ◽  
Automated System ◽  
Aerial Photographs ◽  
Test Set ◽  
Photo Identification ◽  
Eubalaena Australis ◽  
Right Whales ◽  
Southern Right Whales ◽  
Similarity Scores

Photographs showing the callosity patterns of southern right whales (Eubalaena australis) are currently compared by eye to identifyindividuals and monitor their occurrence within certain areas. This paper describes software designed to reduce the number of by eyecomparisons required to maintain each of the existing local photo-identification catalogues. The software is used to extract, from eachphotograph, a viewpoint-independent description of the shape and location of each callosity which generates a parallel catalogue of extracts.This is then compared with the description extracted from each new photograph to generate a list of similarity scores and thus highlightlikely matches. The software can also be used to compare the different catalogues of extracts with each other. Using a test set of 67photographs of 23 whales taken from 1974 to 1986, the software reduced the number of by eye comparisons required to identify allindividuals by 93% when compared with a purely random search.

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