Acoustic occurrence of baleen whales, particularly blue, fin, and humpback whales, off eastern Canada, 2015–2017

The ever-increasing human demand for fossil fuels has resulted in the expansion of oil exploration efforts to waters over the continental shelf. These waters are largely utilized by a complex biological community. Large baleen whales, in particular, utilize continental shelf waters as breeding and calving grounds, foraging grounds, and also as migration corridors. We developed a dynamic approach to estimate the likelihood that individuals from different populations of blue whales Balaenoptera musculus and humpback whales Megaptera novaeangliae could be exposed to idealized, simulated seismic surveys as they move over the continental shelf. Animal tracking data for the different populations were filtered, and behaviors (transit and foraging) were inferred from the tracks using hidden Markov models. We simulated a range of conditions of exposure by having the source of noise affecting a circular area of different radii (5, 25, 50 and 100 km), moving along a gridded transect of 270 and 2500 km2 at a constant speed of 9 km h-1, and starting the simulated surveys every week of the year. Our approach allowed us to identify the temporal variability in the susceptibility of the different populations under study, as we ran the simulations for an entire year, allowing us to identify periods when the surveys would have an intensified effect on whales. Our results highlight the importance of understanding the behavior and ecology of individuals in a site-specific context when considering the likelihood of exposure to anthropogenic disturbances, as the habitat utilization patterns of each population are highly variable.

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

10.1101/2020.12.31.424937 ◽

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.

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‘Megapclicks’: acoustic click trains and buzzes produced during night-time foraging of humpback whales ( Megaptera novaeangliae )

Biology Letters ◽

10.1098/rsbl.2007.0281 ◽

2007 ◽

Vol 3 (5) ◽

pp. 467-470 ◽

Cited By ~ 68

Author(s):

Alison K Stimpert ◽

David N Wiley ◽

Whitlow W.L Au ◽

Mark P Johnson ◽

Roland Arsenault

Keyword(s):

Megaptera Novaeangliae ◽

Humpback Whales ◽

Baleen Whale ◽

Night Time ◽

Baleen Whales ◽

Acoustic Behaviour ◽

Suction Cup ◽

Form Part ◽

Acoustic Tags ◽

Feeding Area

Humpback whales ( Megaptera novaeangliae ) exhibit a variety of foraging behaviours, but neither they nor any baleen whale are known to produce broadband clicks in association with feeding, as do many odontocetes. We recorded underwater behaviour of humpback whales in a northwest Atlantic feeding area using suction-cup attached, multi-sensor, acoustic tags (DTAGs). Here we describe the first recordings of click production associated with underwater lunges from baleen whales. Recordings of over 34 000 ‘megapclicks’ from two whales indicated relatively low received levels at the tag (between 143 and 154 dB re 1 μPa pp), most energy below 2 kHz, and interclick intervals often decreasing towards the end of click trains to form a buzz. All clicks were recorded during night-time hours. Sharp body rolls also occurred at the end of click bouts containing buzzes, suggesting feeding events. This acoustic behaviour seems to form part of a night-time feeding tactic for humpbacks and also expands the known acoustic repertoire of baleen whales in general.

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

PLoS ONE ◽

10.1371/journal.pone.0245409 ◽

2021 ◽

Vol 16 (6) ◽

pp. e0245409

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

Animal 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 observations and photo-identifications of humpback whales (Megaptera novaeangliae) feeding within a fjord system in the Canadian Pacific (primarily within Gitga’at First Nation waters), we have documented long-term pair bonds (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 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 species. 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.

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Observations on Three Species of Baleen Whales off Northern Newfoundland and Adjacent Waters

Journal of the Fisheries Research Board of Canada ◽

10.1139/f77-206 ◽

1977 ◽

Vol 34 (9) ◽

pp. 1436-1440 ◽

Cited By ~ 10

Author(s):

Judith Perkins ◽

Hal Whitehead

Keyword(s):

Key Words ◽

Population Size ◽

Geographical Distribution ◽

Humpback Whales ◽

Population Estimate ◽

Balaenoptera Acutorostrata ◽

Balaenoptera Physalus ◽

Baleen Whales ◽

Sailing Boat ◽

Water Depths

Minke, Balaenoptera acutorostrata, finback, Balaenoptera physalus, and humpback whales, Megaptera novaeangliae, were observed off northern Newfoundland and southern Labrador between June and September 1975, principally from a sailing boat. Distributions for these species are recorded and correlated with water depths and distances from shore. Several isolated sounds, but no "songs," were recorded from humpback whales in Notre Dame Bay, where a population estimate was calculated based on a new method of photographic marking of individuals. Key words: baleen whales, geographical distribution, population size, photographic tagging

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Net Entanglements of Baleen Whales in the Inshore Fishery of Newfoundland

Journal of the Fisheries Research Board of Canada ◽

10.1139/f79-075 ◽

1979 ◽

Vol 36 (5) ◽

pp. 521-528 ◽

Cited By ~ 14

Author(s):

J. S. Perkins ◽

P. C. Beamish

Keyword(s):

Key Words ◽

Newfoundland And Labrador ◽

Megaptera Novaeangliae ◽

Humpback Whales ◽

Balaenoptera Acutorostrata ◽

Balaenoptera Physalus ◽

Baleen Whales ◽

Minke Whales ◽

Capelin Mallotus Villosus ◽

Inshore Waters

This paper documents net entrapments of baleen whales in the inshore waters of Newfoundland and Labrador. The species involved are principally minke whales (Balaenoptera acutorostrata) and humpback whales (Megaptera novaeangliae). Finback whales (Balaenoptera physalus) are also caught in nets but far less frequently. The timing of these entrapments corresponds with the spawning season for capelin (Mallotus villosus) on the beaches around the province. The magnitude and implications of this problem, both to the whales and the fisherman, are assessed. Key words: baleen whales, net entrapments, mortality assessment, capelin, Balaenoptera acutorostrata, B. physalus, Megaptera novaeangliae

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Scaling of oscillatory kinematics and Froude efficiency in baleen whales

Journal of Experimental Biology ◽

10.1242/jeb.237586 ◽

2021 ◽

Author(s):

William T. Gough ◽

Hayden J. Smith ◽

Matthew S. Savoca ◽

Max F. Czapanskiy ◽

Frank E. Fish ◽

...

Keyword(s):

Body Size ◽

Swimming Speed ◽

High Efficiency ◽

Inertial Sensors ◽

Hydrodynamic Performance ◽

Humpback Whales ◽

Baleen Whale ◽

Baleen Whales ◽

Fin Whale ◽

Locomotor Strategy

High efficiency lunate-tail swimming with high-aspect-ratio lifting surfaces has evolved in many vertebrate lineages, from fish to cetaceans. Baleen whales (Mysticeti) are the largest swimming animals that exhibit this locomotor strategy and present an ideal study system to examine how morphology and the kinematics of swimming scale to the largest body sizes. We used data from whale-borne inertial sensors coupled with morphometric measurements from aerial drones to calculate the hydrodynamic performance of oscillatory swimming in six baleen whale species ranging in body length from 5-25m (fin whale, Balaenoptera physalus; Bryde's whale, Balaenoptera edeni; sei whale, Balaenoptera borealis; Antarctic minke whales, Balaenoptera bonaerensis; humpback whales, Megaptera novaeangliae; and blue whales, Balaenoptera musculus). We find that mass-specific thrust increases with both swimming speed and body size. Froude efficiency, defined as the ratio of useful power output to the rate of energy input (Sloop, 1978), generally increased with swimming speed but decreased on average with increasing body size. This finding is contrary to previous results in smaller animals where Froude efficiency increased with body size. Although our empirically-parameterized estimates for swimming baleen whale drag was higher than that of a simple gliding model, oscillatory locomotion at this scale exhibits generally high Froude efficiency as in other adept swimmers. Our results quantify the fine-scale kinematics and estimate the hydrodynamics of routine and energetically expensive swimming modes at the largest scale.

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Norrisanima miocaena, a new generic name and redescription of a stem balaenopteroid mysticete (Mammalia, Cetacea) from the Miocene of California

PeerJ ◽

10.7717/peerj.7629 ◽

2019 ◽

Vol 7 ◽

pp. e7629 ◽

Cited By ~ 1

Author(s):

Matthew S. Leslie ◽

Carlos Mauricio Peredo ◽

Nicholas D. Pyenson

Keyword(s):

Phylogenetic Analyses ◽

Original Description ◽

Type Specimen ◽

Megaptera Novaeangliae ◽

Morphological Data ◽

Humpback Whales ◽

Phylogenetic Position ◽

Data Sets ◽

Baleen Whales ◽

Size Evolution

Rorqual whales are among the most species rich group of baleen whales (or mysticetes) alive today, yet the monophyly of the traditional grouping (i.e., Balaenopteridae) remains unclear. Additionally, many fossil mysticetes putatively assigned to either Balaenopteridae or Balaenopteroidea may actually belong to stem lineages, although many of these fossil taxa suffer from inadequate descriptions of fragmentary skeletal material. Here we provide a redescription of the holotype of Megaptera miocaena, a fossil balaenopteroid from the Monterey Formation of California, which consists of a partial cranium, a fragment of the rostrum, a single vertebra, and both tympanoperiotics. Kellogg (1922) assigned the type specimen to the genus Megaptera Gray (1846), on the basis of its broad similarities to distinctive traits in the cranium of extant humpback whales (Megaptera novaeangliae (Borowski, 1781)). Subsequent phylogenetic analyses have found these two species as sister taxa in morphological datasets alone; the most recent systematic analyses using both molecular and morphological data sets place Megaptera miocaena as a stem balaenopteroid unrelated to humpback whales. Here, we redescribe the type specimen of Megaptera miocaena in the context of other fossil balaenopteroids discovered nearly a century since Kellogg’s original description and provide a morphological basis for discriminating it from Megaptera novaeangliae. We also provide a new generic name and recombine the taxon as Norrisanima miocaena, gen. nov., to reflect its phylogenetic position outside of crown Balaenopteroidea, unrelated to extant Megaptera. Lastly, we refine the stratigraphic age of Norrisanima miocaena, based on associated microfossils to a Tortonian age (7.6–7.3 Ma), which carries implications for understanding the origin of key features associated with feeding and body size evolution in this group of whales.

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Population abundance of recovering humpback whales (Megaptera novaeangliae) and other baleen whales in the Scotia Arc, South Atlantic

Marine Ecology Progress Series ◽

10.3354/meps13849 ◽

2021 ◽

Author(s):

M Baines ◽

N Kelly ◽

M Reichelt ◽

C Lacey ◽

S Pinder ◽

...

Keyword(s):

South Atlantic ◽

Megaptera Novaeangliae ◽

Humpback Whales ◽

Population Abundance ◽

Baleen Whales ◽

Scotia Arc

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Multiple Levels of Single-Strand Slippage at Cetacean Tri- and Tetranucleotide Repeat Microsatellite Loci

Genetics ◽

10.1093/genetics/151.1.285 ◽

1999 ◽

Vol 151 (1) ◽

pp. 285-296 ◽

Cited By ~ 1

Author(s):

Per J Palsbøll ◽

Martine Bérubé ◽

Hanne Jørgensen

Keyword(s):

Microsatellite Loci ◽

Relative Rate ◽

Logical Consequence ◽

Single Strand ◽

Humpback Whales ◽

Balaenoptera Physalus ◽

Tetranucleotide Repeat ◽

Baleen Whales ◽

Repeat Array ◽

Multiple Levels

Abstract Between three and six tri- and tetranucleotide repeat microsatellite loci were analyzed in 3720 samples collected from four different species of baleen whales. Ten of the 18 species/locus combinations had imperfect allele arrays, i.e., some alleles differed in length by other than simple integer multiples of the basic repeat length. The estimate of the average number of alleles and heterozygosity was higher at loci with imperfect allele arrays relative to those with perfect allele arrays. Nucleotide sequences of 23 different alleles at one tetranucleotide repeat microsatellite locus in fin whales, Balaenoptera physalus, and humpback whales, Megaptera novaeangliae, revealed sequence changes including perfect repeats only, multiple repeats, and partial repeats. The relative rate of the latter two categories of mutation was estimated at 0.024 of the mutation rate involving perfect repeats only. It is hypothesized that single-strand slippage of partial repeats may provide a mechanism for counteracting the continuous expansion of microsatellite loci, which is the logical consequence of recent reports demonstrating directional mutations. Partial-repeat mutations introduce imperfections in the repeat array, which subsequently could reduce the rate of single-strand slippage. Limited computer simulations confirmed this predicted effect of partial-repeat mutations.

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