scholarly journals Ancestor–descendant relationships in evolution: origin of the extant pygmy right whale, Caperea marginata

2015 ◽  
Vol 11 (1) ◽  
pp. 20140875 ◽  
Author(s):  
Cheng-Hsiu Tsai ◽  
R. Ewan Fordyce
Keyword(s):  
Punctuated Equilibrium ◽  
Fundamental Concept ◽  
Baleen Whales ◽  
Right Whale ◽  
Morphological Stasis

Ancestor–descendant relationships (ADRs), involving descent with modification, are the fundamental concept in evolution, but are usually difficult to recognize. We examined the cladistic relationship between the only reported fossil pygmy right whale, †Miocaperea pulchra , and its sole living relative, the enigmatic pygmy right whale Caperea marginata , the latter represented by both adult and juvenile specimens. †Miocaperea is phylogenetically bracketed between juvenile and adult Caperea marginata in morphologically based analyses, thus suggesting a possible ADR—the first so far identified within baleen whales (Cetacea: Mysticeti). The †Miocaperea–Caperea lineage may show long-term morphological stasis and, in turn, punctuated equilibrium.

scholarly journals Long-term and large-scale epidemiology of Brucella infection in baleen whales and sperm whales in the western North Pacific and Antarctic Oceans

2016 ◽  
Vol 78 (9) ◽  
pp. 1457-1464 ◽  
Author(s):  
Kazue OHISHI ◽  
Takeharu BANDO ◽  
Erika ABE ◽  
Yasushi KAWAI ◽  
Yoshihiro FUJISE ◽  
...  
Keyword(s):  
North Pacific ◽  
Western North Pacific ◽  
Large Scale ◽  
Sperm Whales ◽  
Baleen Whales

Great Whales

2008 ◽  
Author(s):  
John Bannister
Keyword(s):  
Sperm Whale ◽  
Modern Technology ◽  
Current Status ◽  
Blue Whale ◽  
Baleen Whales ◽  
Fin Whale ◽  
Right Whale ◽  
Toothed Whale ◽  
History Of ◽  
Storey Building

Whales are mysterious and fascinating creatures. Despite modern technology, their world is still largely unexplored and unknown. They can only be seen, or rather glimpsed, when they are near the sea surface, either from boats, or perhaps from shore, or underwater by divers. They also reach astonishing sizes – the blue whale, for example, can grow to 30 metres in length, equivalent to the height of a six-storey building, and can weigh more than 130 tonnes. Seven ‘Great Whales’ are found in the coastal waters surrounding Australia. These include six of the largest baleen whales – blue whale, fin whale, humpback whale, sei whale, Bryde’s whale and southern right whale – and the sperm whale, the largest toothed whale. This book provides a detailed account of these extraordinary mammals. As well as the seven Great Whales, a smaller species – the minke whale – is included because of its special interest to Australians. The book describes whales’ highly specialised mammalian structure and biology, and the history of people’s association with them, at first through legend and wonder, then whaling, and more recently whale watching. It also looks at their past and current status, and the conservation initiatives that are in place to protect them from existing or potential threats. With both historical and recent photographs, as well as an extensive glossary, Great Whales will be enjoyed by natural history enthusiasts, zoologists and students alike.

Half a century of sightings data of southern right whales in Mar del Plata (Buenos Aires, Argentina)

2019 ◽  
Vol 100 (1) ◽  
pp. 165-171
Author(s):  
Maria A. Mandiola ◽  
Gisela Giardino ◽  
Julián Bastida ◽  
Sergio Morón ◽  
Diego H. Rodríguez ◽  
...  
Keyword(s):  
Buenos Aires ◽  
Buenos Aires Province ◽  
Western Atlantic ◽  
Right Whale ◽  
Eubalaena Australis ◽  
Coastal Marine ◽  
Past Half Century ◽  
Southern Right Whales ◽  
Inshore Waters

AbstractIn South-western Atlantic waters, individuals of the southern right whale (SRW) Eubalaena australis spend part of the year (the austral winter and spring) in northern inshore waters where they breed and then migrate to southern feeding grounds during the summer. Mar del Plata (MDP) is located between two main reproductive areas (Península Valdés-Argentina and Santa Catarina-Brazil). The purpose of the present study is to report the presence of SRWs on their journey off the coast of MDP based on sighting records during the past half century. We carried out whale observations through systematic weekly coastal marine mammal surveys in different points of the MDP area from 1966 to 2016. The first SRW sighting was recorded in 1970; since then, sighting frequency has gradually increased, reaching a peak of 28 sightings (N = 63 whales) in 2016. These are unique long-term sighting records of SRWs in Argentina and the first on their journey off the shores of Buenos Aires province. We expect that these results will help local authorities to regulate tourism and other activities in the area and thereby contribute to the conservation of the species.

scholarly journals Strong and lasting impacts of past global warming on baleen whale and prey abundance

2018 ◽  
Author(s):  
Andrea A. Cabrera ◽  
Elena Schall ◽  
Martine Bérubé ◽  
Lutz Bachmann ◽  
Simon Berrow ◽  
...  
Keyword(s):  
Global Warming ◽  
North Atlantic Ocean ◽  
Marine Ecosystem ◽  
Marine Ecosystems ◽  
Prey Abundance ◽  
Baleen Whale ◽  
Long Term Effects ◽  
Baleen Whales ◽  
Genome Wide

AbstractThe demography of baleen whales and their prey during the past 30 thousand years was assessed to understand the effects of past rapid global warming on marine ecosystems. Mitochondrial and genome-wide DNA sequence variation in eight baleen whale and seven prey species revealed strong, ocean-wide demographic changes that were correlated with changes in global temperatures and regional oceanographic conditions. In the Southern Ocean baleen whale and prey abundance increased exponentially and in apparent synchrony, whereas changes in abundance varied among species in the more heterogeneous North Atlantic Ocean. The estimated changes in whale abundance correlated with increases in the abundance of prey likely driven by reductions in sea-ice cover and an overall increase in primary production. However, the specific regional oceanographic environment, trophic interactions and species ecology also appeared to play an important role. Somewhat surprisingly the abundance of baleen whales and prey continued to increase for several thousand years after global temperatures stabilized. These findings warn of the potential for dramatic, long-term effects of current climate changes on the marine ecosystem.One Sentence SummaryThe effects of past global warming on marine ecosystems were drastic, system-wide and long-lasting.

scholarly journals Social survival: humpback whales (Megaptera novaeangliae) use social structure to partition ecological niches within proposed critical habitat

2020 ◽  
Author(s):  
Janie Wray ◽  
Eric Keen ◽  
Éadin N. O’Mahony
Keyword(s):  
Habitat Use ◽  
Social Structure ◽  
Niche Partitioning ◽  
Megaptera Novaeangliae ◽  
Humpback Whales ◽  
Baleen Whales ◽  
Fjord System ◽  
The Social ◽  
Social Niche

ABSTRACTAnimal culture and social bonds are relevant to wildlife conservation because they influence patterns of geography, behavior, and strategies of survival. Numerous examples of socially-driven habitat partitioning and ecological-niche specialization can be found among vertebrates, including toothed whales. But such social-ecological dynamics, described here as ‘social niche partitioning’, are not known among baleen whales, whose societies -- particularly on foraging grounds -- are largely perceived as unstructured and incidental to matters of habitat use and conservation. However, through 16 years of behavioral and photo-identification observations of humpback whales (Megaptera novaeangliae) feeding within a fjord system in British Columbia, Canada, we have documented long-term pair bonds (lasting up to 12 years) as well as a complex societal structure, which corresponds closely to persistent patterns in feeding strategy, long-term site fidelity (extended seasonal occupancy and annual rate of return up to 75%), specific geographic preferences within the fjord system, and other forms of habitat use. Randomization tests of network congruency and clustering algorithms were used to test for overlap in patterns of social structure and habitat use, which confirmed the occurrence of social niche partitioning on the feeding grounds of this baleen whale. In addition, we document the extensive practice of group bubble net feeding in Pacific Canada. This coordinated feeding behavior was found to strongly mediate the social structure and habitat use within this humpback whale society. Additionally, during our 2004 – 2019 study, we observed a shift in social network structure in 2010 – 2012, which corresponded with environmental and demographic shifts including a sudden decline in the population’s calving rate. Our findings indicate that the social lives of humpback whales, and perhaps baleen whales generally, are more complex than previously supposed and should be a primary consideration in the assessment of potential impacts to important habitat.

scholarly journals A Miocene pygmy right whale fossil from Australia

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5025 ◽  
Author(s):  
Felix G. Marx ◽  
Travis Park ◽  
Erich M.G. Fitzgerald ◽  
Alistair R. Evans
Keyword(s):  
Southern Hemisphere ◽  
Late Miocene ◽  
External Morphology ◽  
Baleen Whales ◽  
Right Whale ◽  
Right Whales ◽  
Molecular Divergence ◽  
Living Species ◽  
Divergence Estimates ◽  
Single Living

Neobalaenines are an enigmatic group of baleen whales represented today by a single living species: the pygmy right whale, Caperea marginata, found only in the Southern Hemisphere. Molecular divergence estimates date the origin of pygmy right whales to 22–26 Ma, yet so far there are only three confirmed fossil occurrences. Here, we describe an isolated periotic from the latest Miocene of Victoria (Australia). The new fossil shows all the hallmarks of Caperea, making it the second-oldest described neobalaenine, and the oldest record of the genus. Overall, the new specimen resembles C. marginata in its external morphology and details of the cochlea, but is more archaic in it having a hypertrophied suprameatal area and a greater number of cochlear turns. The presence of Caperea in Australian waters during the Late Miocene matches the distribution of the living species, and supports a southern origin for pygmy right whales.

First molecular estimate of sex-ratio of southern right whale calves, Eubalaena australis, for Brazilian waters

2009 ◽  
Vol 89 (5) ◽  
pp. 1003-1007 ◽  
Author(s):  
Larissa Rosa de Oliveira ◽  
Paulo Henrique Ott ◽  
Paulo A.C. Flores ◽  
Salvatore Siciliano ◽  
Raquel Santos de Almeida ◽  
...  
Keyword(s):  
Sex Ratio ◽  
The Other ◽  
Brazilian Coast ◽  
Southern Brazil ◽  
Rio Grande Do Sul ◽  
Original Population ◽  
Baleen Whales ◽  
Right Whale ◽  
Eubalaena Australis ◽  
Southern Right Whales

The southern right whale (Eubalaena australis) was one of the most intensively hunted whales between the 17th and 20th centuries in the southern hemisphere. Recent estimates indicate that today there are around 7000 whales, representing 5 to 10% of its original population. On the other hand, recent studies estimated that the population that migrates to the Brazilian coast grew by 14% from 1987 to 2003. However, there is no information about sex-ratio for adults or for calves in this region, which is an important parameter for understanding the biology of the species. We present here the first estimate of calves' sex-ratio of southern right whales found along the southern Brazilian coast, one of the most important wintering grounds for the species. Sex was molecularly indentified for 21 biopsies collected from calves between 1998 and 2002, along the coast of Rio Grande do Sul and Santa Catarina States, in southern Brazil. The sex-ratio was two females for one male, however, it was not statistically different (χ2 test, α = 0.05; df = 1) from the expected ratio of 1:1. This result is in accordance with the sex-ratio estimated for the species of all ages using external morphology (and behaviour information), as well as for most species of baleen whales.

scholarly journals Evidence that ship noise increases stress in right whales

2012 ◽  
Vol 279 (1737) ◽  
pp. 2363-2368 ◽  
Author(s):  
Rosalind M. Rolland ◽  
Susan E. Parks ◽  
Kathleen E. Hunt ◽  
Manuel Castellote ◽  
Peter J. Corkeron ◽  
...  
Keyword(s):  
Low Frequency ◽  
Acoustic Signals ◽  
Frequency Noise ◽  
Underwater Noise ◽  
Baleen Whales ◽  
Ship Traffic ◽  
Right Whale ◽  
Right Whales ◽  
North Atlantic Right Whales ◽  
Shipping Traffic

Baleen whales ( Mysticeti ) communicate using low-frequency acoustic signals. These long-wavelength sounds can be detected over hundreds of kilometres, potentially allowing contact over large distances. Low-frequency noise from large ships (20–200 Hz) overlaps acoustic signals used by baleen whales, and increased levels of underwater noise have been documented in areas with high shipping traffic. Reported responses of whales to increased noise include: habitat displacement, behavioural changes and alterations in the intensity, frequency and intervals of calls. However, it has been unclear whether exposure to noise results in physiological responses that may lead to significant consequences for individuals or populations. Here, we show that reduced ship traffic in the Bay of Fundy, Canada, following the events of 11 September 2001, resulted in a 6 dB decrease in underwater noise with a significant reduction below 150 Hz. This noise reduction was associated with decreased baseline levels of stress-related faecal hormone metabolites (glucocorticoids) in North Atlantic right whales ( Eubalaena glacialis ). This is the first evidence that exposure to low-frequency ship noise may be associated with chronic stress in whales, and has implications for all baleen whales in heavy ship traffic areas, and for recovery of this endangered right whale population.

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