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 ◽  
...  
2020 ◽  
Vol 41 ◽  
pp. 373-383
Author(s):  
K Stamation ◽  
M Watson ◽  
P Moloney ◽  
C Charlton ◽  
J Bannister

In Australian waters, southern right whales Eubalaena australis form 2 genetically distinct populations that have shown contrasting patterns of recovery since whaling ceased: a western population in South Australia and Western Australia and an eastern population in southeastern Australia (Tasmania, Victoria and New South Wales). Here, we provide an abundance estimate derived from a breeding female superpopulation mark-recapture model for the southeastern southern right whale population. The population comprises 268 individuals (68 breeding females) and has increased at a rate of 4.7% per annum between 1996 and 2017. There has been no significant change in the annual abundance of mother-calf pairs sighted at the only calving ground (Logans Beach in Victoria) over the last 3 decades. The total number of southern right whales (i.e. all adults and calves) using the southeastern Australian coastline has increased by 7% since 1985. Unlike the population estimate (which was restricted to breeding females sighted prior to the post-breeding southward migration), this estimate is likely to include transiting whales from the southwestern population. The theoretical population model predicts 19 breeding females at Logans Beach in 2018 and 28 in 2028; the actual number of breeding females, as of 2018, is 14. This study provides the first complete estimate of population size and rate of increase of southern right whales along the southeastern Australian coastline. This knowledge is critical for assessing population status and recovery of southern right whales in Australia. It provides a basis for monitoring persistence and responses of the population to environmental stressors.


2020 ◽  
pp. 103-110 ◽  
Author(s):  
John Bannister

The history of Australian right whaling is briefly reviewed. Most catching took place in the first half of the 19th century, with a peak inthe 1830s, involving bay whaling by locals and visiting whaleships in winter and whaling offshore in the summer. In the early 20th century,right whales were regarded as at least very rare, if not extinct. The first published scientific record for Australian waters in the 20th centurywas a sighting near Albany, Western Australia, in 1955. Increasing sightings close to the coast in winter and spring led to annual aerialsurveys off southern Western Australia from 1976. To allow for possible effects of coastwise movements, coverage was extended intoSouth Australian waters from 1993. Evidence from 19th century pelagic catch locations, recent sightings surveys, 1960s Soviet catch dataand photographically-identified individuals is beginning to confirm earlier views about likely seasonal movements to and from warm watercoastal breeding grounds and colder water feeding grounds. Increase rates of ca 7-13% have been observed since 1983. Some effects ofdifferent breeding female cohort strength are now beginning to appear. A minimum population size of ca 700 for the period 1995-97 issuggested for the bulk of the ‘Australian’ population, i.e. animals approaching the ca 2,000km of coast between Cape Leeuwin, WesternAustralia and Ceduna, South Australia.


2020 ◽  
pp. 133-143
Author(s):  
Victoria J. Rowntree ◽  
Roger S. Payne ◽  
Donald M. Schell

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.


Harmful Algae ◽  
2017 ◽  
Vol 68 ◽  
pp. 248-257 ◽  
Author(s):  
Valeria C. D’Agostino ◽  
Mariana Degrati ◽  
Viviana Sastre ◽  
Norma Santinelli ◽  
Bernd Krock ◽  
...  

2020 ◽  
pp. 157-160
Author(s):  
Antonio B. Greig ◽  
Eduardo R. Secchi ◽  
Alexandre N. Zerbini ◽  
Luciano Dalla Rosa

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.


2020 ◽  
pp. 291-295
Author(s):  
Lex Hiby ◽  
Phil Lovell

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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