Mortalities of right whales and related anthropogenic factors in South African waters, 1963-1998

2020 ◽  
pp. 171-176
Author(s):  
Peter B. Best ◽  
Victor M. Peddemors ◽  
Victor G. Cockcroft ◽  
Nan Rice
Keyword(s):  
Population Growth ◽  
South African ◽  
Causes Of Death ◽  
Anthropogenic Factors ◽  
Population Recovery ◽  
Right Whale ◽  
Right Whales ◽  
Southern Right Whales

Between 1963 and 1998, 55 mortalities of southern right whales and a further three ‘possible right whale’ mortalities were recorded on theSouth African coastline. Of the known right whale mortalities, 31 could be classified as ‘calves of the year’, 8 as juveniles and 14 as adults.Relatively few (6.5-16.1%) of the calf mortalities could be attributed to anthropogenic factors, compared to juveniles (25-50%) and adults(35.7-57.1%). Apparent causes of death included ship strikes (4 definite, 7 possible) and entanglement (4 definite, 1 possible), with oneharpooning incident. Five non-fatal ship strikes and 16 instances of non-fatal entanglement were also recorded. Whilst the gear mostcommonly involved in non-fatal entanglement was crayfish trap lines, three of the four entanglement fatalities involved longline gear. Theincidence of scars attributable to previous entanglement remained constant amongst mature females from 1979-1997, at 3-4%. Recordedmortalities increased over the period 1963-1997 at a rate no different from that of population growth over the same period. The current levelof anthropogenic mortality does not seem to be affecting population recovery.

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.

Composition and Possible Function of Social Groupings of Southern Right Whales in South African Waters

Behaviour ◽  
2003 ◽  
Vol 140 (11-12) ◽  
pp. 1469-1494 ◽  
Author(s):  
Desray Reeb ◽  
Peter Best ◽  
Per Palsbøll ◽  
Keyword(s):  
South African ◽  
Right Whales ◽  
Southern Right Whales

Pathologic findings and causes of death in southern right whales Eubalaena australis, Brazil

2019 ◽  
Vol 137 (1) ◽  
pp. 23-31
Author(s):  
KR Groch ◽  
JL Catão-Dias ◽  
KR Groch ◽  
CKM Kolesnikovas ◽  
PV de Castilho ◽  
...  
Keyword(s):  
Causes Of Death ◽  
Eubalaena Australis ◽  
Pathologic Findings ◽  
Right Whales ◽  
Southern Right Whales

Southern right whales (Eubalaena australis) off Torres, Brazil: group characteristics, movements, and insights into the role of the Brazilian-Uruguayan wintering ground

Mammalia ◽  
2017 ◽  
Vol 81 (3) ◽  
Author(s):  
Daniel Danilewicz ◽  
Ignacio B. Moreno ◽  
Maurício Tavares ◽  
Federico Sucunza
Keyword(s):  
Right Whale ◽  
Eubalaena Australis ◽  
Right Whales ◽  
Southern Right Whales ◽  
Group Characteristics ◽  
Wintering Ground

AbstractThe southern right whale (SRW),

Humpback whales Megaptera novaeangliae and southern right whales Eubalaena australis in Gerlache Strait, Antarctica

Polar Record ◽  
1988 ◽  
Vol 24 (148) ◽  
pp. 15-20 ◽  
Author(s):  
Gregory S. Stone ◽  
William M. Hamner
Keyword(s):  
Open Water ◽  
Euphausia Superba ◽  
Megaptera Novaeangliae ◽  
Humpback Whales ◽  
Southern Limit ◽  
Right Whale ◽  
Eubalaena Australis ◽  
Right Whales ◽  
Southern Right Whales ◽  
The Right

AbstractDuring surveys conducted 2–20 April 1986 in Gerlache Strait, Antarctic Peninsula, 103 humpback whales Megaptera novaeangliae and eight right whales Eubalaena australis were sighted. The right whale sightings extend the southern limit of known distribution for the species. Humpback and right whale densities were respectively 0.22 (sd 0.23) and 0.01 (sd 0.06) whales per survey mile. Highest densities for both species were recorded inside bays, rather than in the relatively open water of Gerlache Strait. Both species were feeding on Antarctic krill Euphausia superba. Twenty-three humpback and four right whales were identified individually using photographs of natural features. Also included are sighting records of 18 southern bottlenose whales Hyperoodon planifrons.

scholarly journals Temporal variation in the vocal behaviour of southern right whales in the Auckland Islands, New Zealand

2019 ◽  
Vol 6 (3) ◽  
pp. 181487 ◽  
Author(s):  
T. A. Webster ◽  
S. M. Van Parijs ◽  
W. J. Rayment ◽  
S. M. Dawson
Keyword(s):  
New Zealand ◽  
North Atlantic ◽  
Right Whale ◽  
Vocal Behaviour ◽  
Analysis Process ◽  
Right Whales ◽  
North Atlantic Right Whales ◽  
Southern Right Whales ◽  
Contact Calls ◽  
Made In

Autonomous recorders are frequently used for examining vocal behaviour of animals, and are particularly effective in remote habitats. Southern right whales are known to have an extensive acoustic repertoire. A recorder was moored at the isolated sub-Antarctic Auckland Islands for a year to examine whether the acoustic behaviour of southern right whales differed seasonally and throughout the day at their main calving ground in New Zealand. Recordings were made in each month except June, and vocalizations were audible in all months with recordings except January. A total of 35 487 calls were detected, of which upcalls were the most common (11 623). Call rate peaked in August (288 ± 5.9 [s.e.] calls/hour) and July (194 ± 8.3). Vocal behaviour varied diurnally with highest call rates detected at dusk and night, consistent with the concept that upcalls function primarily as contact calls. Zero-inflated model results confirmed that seasonal variation was the most important factor for explaining differences in vocal behaviour. An automated detector designed to expedite the analysis process for North Atlantic right whales correctly identified 80% of upcalls, although false detections were frequent, particularly when call rates were low. This study is the first to attempt year-round monitoring of southern right whale presence in New Zealand.

scholarly journals Population estimate and rate of increase of southern right whales Eubalaena australis in southeastern Australia

2020 ◽  
Vol 41 ◽  
pp. 373-383
Author(s):  
K Stamation ◽  
M Watson ◽  
P Moloney ◽  
C Charlton ◽  
J Bannister
Keyword(s):  
South Australia ◽  
Population Estimate ◽  
Abundance Estimate ◽  
Right Whale ◽  
Eubalaena Australis ◽  
Southeastern Australia ◽  
Rate Of Increase ◽  
Right Whales ◽  
Southern Right Whales ◽  
Australian Coastline

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.

scholarly journals Occurrence of southern right whales (Eubalaena australis) along southeastern Brazil

2020 ◽  
pp. 153-156
Author(s):  
Marcos César De Oliveira Santo ◽  
Salvatore Siciliano ◽  
Shirley Pacheco de Souza ◽  
Jose Luis Altmayer Pizzorno
Keyword(s):  
Southeastern Brazil ◽  
Incidental Capture ◽  
Right Whale ◽  
Eubalaena Australis ◽  
Right Whales ◽  
Southern Right Whales

This paper reports on the occurrence of southern right whales (Eubalaena australis) in southeastern Brazilian waters (18°S-25°S), withevidence of their use of the region as an important calving area. Only in recent years have right whale sightings and strandings been reportedregularly within the surveyed area. Of 71 distinct sightings reported since 1936, 39 (54.9%) were mother-calf pairs observed close to theshore. Most of these sightings (91.5%) were reported from early July to late October. Eight confirmed strandings of this species wereobserved within the surveyed area, six of which were between July and October. Stranded calves represented 62.5% of these records. Twocalves showed evidence of incidental capture. The increasing number of sightings, and recent reports of stranded calves and one adultfemale could be indicative of an increase in cetacean research efforts in the region. However, it also suggests use of the southeasternBrazilian coast as an important right whale calving area.

Southern right whale on the coast of Rio de Janeiro State, Brazil: conflict between conservation and human activity

2007 ◽  
Vol 87 (1) ◽  
pp. 105-107 ◽  
Author(s):  
Liliane Lodi ◽  
Marcelo Tardelli Rodrigues
Keyword(s):  
Human Activity ◽  
Human Activities ◽  
Rio De Janeiro ◽  
Distinct Pattern ◽  
Brazilian Coast ◽  
Widespread Distribution ◽  
Right Whale ◽  
Right Whales ◽  
Southern Right Whales ◽  
Janeiro State

Between 1993 and 2005, 68 sightings of southern right whales were recorded along 400 km of coastline between Paraty Bay (23°13'S 44°42'W) and Macaé (22°22'S 41°47'W), Rio de Janeiro State, south-eastern Brazilian coast. Mother/calf pairs represented 66.1% of sightings. Only solitary individuals showed a distinct pattern of occurrence. Females with calf did not show a distinct pattern of occurrence suggesting their widespread distribution in the area. Analysis of the records and detailed accounts of the sightings of southern right whales reveal that there exist conflicts between the animals and human activities such as harassment and collision with boats during attempted rescues, accidental entanglement in fishing nets and intentional mortality, which may have a bearing in the conservation of the species in Brazilian waters.

scholarly journals A note on recent sightings of southern right whales (Eubalaena australis) along the east coast of Madagascar

2001 ◽  
pp. 177-180
Author(s):  
Howard C. Rosenbaum
Keyword(s):  
South African ◽  
East Coast ◽  
Long Distance ◽  
Eubalaena Australis ◽  
Mitochondrial Haplotypes ◽  
Single Animal ◽  
Right Whales ◽  
Southern Right Whales ◽  
Breeding Grounds ◽  
Feeding Grounds

Southern right whales (Eubalaena australis) are distributed throughout the Southern Hemisphere, where they seasonally migrate betweenhigh latitude feeding grounds and low latitude breeding grounds. While there are detailed records of historical and recent whaling off thesouthern, southwestern and southeastern African coasts, historical catches in Madagascar’s waters are poorly documented. There have alsobeen no recent, documented sightings of southern right whales off the east coast of Madagascar. Here we report two sightings, one of asingle individual in Antongil Bay in northeastern Madagascar and the other of a mother and calf pair near Fort Dauphin on the southeasterncoast. DNA obtained from a biopsy sample of the single animal showed it was a male possessing one of the common South Atlantic rightwhale mitochondrial haplotypes. The available DNA data provide limited suggestive evidence that the individuals documented offMadagascar represent long-distance migrants from the well-documented South African population. However, the possibility that thesesouthern right whales are members of a small or remnant population from the historical whaling grounds of Delagoa Bay, Sofala Bay orthe Crozet Island feeding grounds cannot be excluded. Regardless of population assignment for these individuals, it appears that somesouthern right whales may be using different parts of Madagascar’s east coast during the wintering season

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