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1
Rastogi, Toolika, Moira W. Brown, Brenna A. McLeod, et al. "Genetic analysis of 16th-century whale bones prompts a revision of the impact of Basque whaling on right and bowhead whales in the western North Atlantic." Canadian Journal of Zoology 82, no. 10 (2004): 1647–54. http://dx.doi.org/10.1139/z04-146.
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The North Atlantic right whale, Eubalaena glacialis (Müller, 1776), is one of the world's most endangered large cetaceans. It is widely believed that Basque whalers caused the most dramatic decline of this species in the western North Atlantic during the early-16th and 17th centuries. Previous osteological analysis of 17 historic bones suggested that 50% of the Basque harvest consisted of right whales and 50% of bowhead whales, Balaena mysticetus L., 1758. This 50:50 ratio has been used to estimate pre-exploitation population size, which has subsequently formed the basis of recovery goals and plans for the North Atlantic right whale. Genetic analysis of 21 bones, 13 identified as right whales and 8 as bowhead whales through osteological examination, indicates that in fact only 1 bone was a right whale and 20 were bowhead whales. Additionally, preliminary microsatellite analyses of this specimen are not consistent with the hypothesis that whaling resulted in the low genetic variation found in this species today. These results differ from what would be expected based on any previous view of Basque whaling, and raise questions regarding the impact of Basque whaling on this species.
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Romero, Aldemaro, and Shelly Kannada. "Comment on “Genetic analysis of 16th-century whale bones prompts a revision of the impact of Basque whaling on right and bowhead whales in the western North Atlantic”." Canadian Journal of Zoology 84, no. 7 (2006): 1059–65. http://dx.doi.org/10.1139/z06-085.
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Rastogi et al. presented their genetic analysis of 16th-century whale bones found on a Basque whaling ship excavated from Red Bay, Labrador Peninsula, Canada. Based on the results from a very small sample, these authors concluded that whaling populations were already depleted before the onset of whaling. This is in direct contradiction to historical data. They also implied that the Basques were the only Europeans whaling in the North Atlantic before the onset of Yankee whaling and that there was a belief that Basque whalers historically killed equal numbers of right and bowhead whales. Here we present data based on historical and archaeological records generated by several authors using different methodologies, which clearly show that (i) Basques were not the only whalers that impacted cetacean populations in the North Atlantic; (ii) the number of whales killed by different peoples for approximately two centuries indicates that both right and bowhead whale population levels were much higher than typically assumed; and (iii) for many years there have been records published indicating that the Basques and others killed more bowhead whales than right whales, at least in the western North Atlantic.
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McLeod, B. A., M. W. Brown, M. J. Moore, et al. "Bowhead whales, and not right whales, were the primary target of 16th- to 17th-century Basque Whalers in the Western North Atlantic." ARCTIC 61, no. 1 (2009): 61. http://dx.doi.org/10.14430/arctic7.
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During the 16th and 17th centuries, Basque whalers travelled annually to the Strait of Belle Isle and Gulf of St. Lawrence to hunt whales. The hunting that occurred during this period is of primary significance for the North Atlantic right whale, Eubalaena glacialis (Müller, 1776), because it has been interpreted as the largest human-induced reduction of the western North Atlantic population, with ~12250–21 000 whales killed. It has been frequently reported that the Basques targeted two species in this region: the North Atlantic right whale and the bowhead whale, Balaena mysticetus L., 1758. To evaluate this hypothesis and the relative impact of this period of whaling on both species, we collected samples from 364 whale bones during a comprehensive search of Basque whaling ports from the 16th to the 17th century in the Strait of Belle Isle and Gulf of St. Lawrence. Bones were found and sampled at 10 of the 20 sites investigated. DNA was extracted from a subset (n = 218) of these samples. Analysis of the mitochondrial cytochrome b region identified five whale species. The identification of only a single right whale bone and 203 bowhead whale bones from at least 72 individuals indicates that the bowhead whale was likely the principal target of the hunt. These results imply that this whaling had a much greater impact (in terms of numbers of whales removed) on the bowhead whale population than on the western North Atlantic right whale population.
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Stone, Gregory S., and William M. Hamner. "Humpback whales Megaptera novaeangliae and southern right whales Eubalaena australis in Gerlache Strait, Antarctica." Polar Record 24, no. 148 (1988): 15–20. http://dx.doi.org/10.1017/s0032247400022300.
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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.
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Woodley, Thomas H., and David E. Gaskin. "Environmental characteristics of North Atlantic right and fin whale habitat in the lower Bay of Fundy, Canada." Canadian Journal of Zoology 74, no. 1 (1996): 75–84. http://dx.doi.org/10.1139/z96-010.
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Characteristics of right whale (Eubalaena glacialis) and fin whale (Balaenoptera physalus) habitat in the lower Bay of Fundy were identified by quantifying physical and biological habitat variables and comparing them to the distribution of whales during the summer and autumn of 1989. Right whales were generally distributed over the Grand Manan Basin, where the bottom topography is relatively flat and the water column was stratified. Calanus finmarchicus, the principal prey species of right whales, was the predominant copepod taken in Zooplankton hauls, and the depth-averaged density (mean 1139/m3) was significantly greater where right whales were present. Fin whales were distributed mainly in shallower areas with high topographic variation that were likely well mixed or contained frontal interfaces between mixed and stratified waters. Herring (Clupea harengus) and euphausiids, both known prey of fin whales, were relatively abundant on echosounder traces in areas where fin whales were present. The habitats of both whale species were primarily characterized by high densities of principal prey species and the physical conditions that facilitate the accumulation of these prey.
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Wade, Paul, Mads Peter Heide-Jørgensen, Kim Shelden, et al. "Acoustic detection and satellite-tracking leads to discovery of rare concentration of endangered North Pacific right whales." Biology Letters 2, no. 3 (2006): 417–19. http://dx.doi.org/10.1098/rsbl.2006.0460.
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The North Pacific right whale, Eubalaena japonica , is one of the most endangered species of whale in the world. On 10 August 2004, two right whales were located in the Bering Sea using headings to right whale calls provided by directional sonobuoys. A satellite-monitored radio tag attached to one of these whales functioned for 40 days. Over the 40-day period, this whale moved throughout a large part of the southeast Bering Sea shelf, including areas of the outer-shelf where right whales have not been seen in decades. In September, multiple right whales were acoustically located and subsequently sighted by another survey vessel approaching a near-real-time position from the tag. An analysis of photographs confirmed at least 17 individual whales (not including the tagged whales). Genetic analysis of biopsy samples identified 17 individuals: 10 males and 7 females. The discovery of seven females was significant, as only one female had been identified in the past. Genetics also confirmed the presence of at least two calves. Although the future of this population is highly uncertain, the discovery of additional females and calves gives some hope that this most critically endangered of all whale populations may still possess the capacity to recover.
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Parks, Susan E., Joseph D. Warren, Karen Stamieszkin, Charles A. Mayo, and David Wiley. "Dangerous dining: surface foraging of North Atlantic right whales increases risk of vessel collisions." Biology Letters 8, no. 1 (2011): 57–60. http://dx.doi.org/10.1098/rsbl.2011.0578.
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North Atlantic right whales are critically endangered and, despite international protection from whaling, significant numbers die from collisions with ships. Large groups of right whales migrate to the coastal waters of New England during the late winter and early spring to feed in an area with large numbers of vessels. North Atlantic right whales have the largest per capita record of vessel strikes of any large whale population in the world. Right whale feeding behaviour in Cape Cod Bay (CCB) probably contributes to risk of collisions with ships. In this study, feeding right whales tagged with archival suction cup tags spent the majority of their time just below the water's surface where they cannot be seen but are shallow enough to be vulnerable to ship strike. Habitat surveys show that large patches of right whale prey are common in the upper 5 m of the water column in CCB during spring. These results indicate that the typical spring-time foraging ecology of right whales may contribute to their high level of mortality from vessel collisions. The results of this study suggest that remote acoustic detection of prey aggregations may be a useful supplement to the management and conservation of right whales.
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Rodrigues, Ana S. L., Anne Charpentier, Darío Bernal-Casasola, et al. "Forgotten Mediterranean calving grounds of grey and North Atlantic right whales: evidence from Roman archaeological records." Proceedings of the Royal Society B: Biological Sciences 285, no. 1882 (2018): 20180961. http://dx.doi.org/10.1098/rspb.2018.0961.
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Right whales ( Eubalaena glacialis ) were extirpated from the eastern North Atlantic by commercial whaling. Grey whales ( Eschrichtius robustus ) disappeared from the entire North Atlantic in still-mysterious circumstances. Here, we test the hypotheses that both species previously occurred in the Mediterranean Sea, an area not currently considered part of their historical range. We used ancient DNA barcoding and collagen fingerprinting methods to taxonomically identify a rare set of 10 presumed whale bones from Roman and pre-Roman archaeological sites in the Strait of Gibraltar region, plus an additional bone from the Asturian coast. We identified three right whales, and three grey whales, demonstrating that the ranges of both of these species historically encompassed the Gibraltar region, probably including the Mediterranean Sea as calving grounds. Our results significantly extend the known range of the Atlantic grey whale, and suggest that 2000 years ago, right and grey whales were common when compared with other whale species. The disappearance of right and grey whales from the Mediterranean region is likely to have been accompanied by broader ecosystem impacts, including the disappearance of their predators (killer whales) and a reduction in marine primary productivity. The evidence that these two coastal and highly accessible species were present along the shores of the Roman Empire raises the hypothesis that they may have formed the basis of a forgotten whaling industry.
9
Taylor, Cynthia R., and William B. Brooksm. "Dissemination of Northern Right Whale (Eubalaena glacialis) Sighting Information to the Southeast U.S. Maritime Community." Marine Technology Society Journal 36, no. 2 (2002): 58–60. http://dx.doi.org/10.4031/002533202787914089.
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Northern right whales (Eubalaena glacialis) are vulnerable to injury and mortality caused by vessel strikes. In an effort to prevent vessel strikes in the southeastern U.S. calving ground, a communication network was implemented to relay right whale sighting information, gathered by aerial survey teams, to mariners in the area. The system, which has evolved substantially since inception, now provides real-time sighting information to the marine community, thus assisting with avoidance of northern right whales. The current system utilizes 25 cloned alphanumeric pagers distributed to various state, federal, military, and industry representatives. Right whale sightings are reported and disseminated via the pagers, and ultimately via Navigational Telex (NAVTEX) to all ships 100 tons or larger in southeastern waters. This system has been successful in alerting mariners to the presence of right whales, however to address the critical management problems confronting this highly endangered species, further research into technological advancements that may assist in the detection of right whales should be encouraged.
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D’Amato, Anthony, and Sudhir K. Chopra. "Whales: Their Emerging Right to Life." American Journal of International Law 85, no. 1 (1991): 21–62. http://dx.doi.org/10.2307/2203067.
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Writers of science fiction have often speculated about what it would be like to discover, on a planet in outer space, a much higher form of intelligence. How would we react to those creatures? Would we be so fearful of them that we would try to kill them? Or would we welcome the opportunity to attempt to understand their language and culture? Stranger than fiction is the fact that there already exists a species of animal life on earth that scientists speculate has higher than human intelligence. The whale has a brain that in some instances is six times bigger than the human brain and its neocortex is more convoluted. Discussing the creative processes of whales, Dr. John Lilly says that a researcher “is struck with the fact that one’s current basic assumptions and even one’s current expectations determine, within certain limits, the results attained with a particular animal at that particular time.” Whales speak to other whales in a language that appears to include abstruse mathematical poetry. They have also developed interspecies communication with dolphins. Whales are the most specialized of all mammals.
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Murison, L. D., and D. E. Gaskin. "The distribution of right whales and Zooplankton in the Bay of Fundy, Canada." Canadian Journal of Zoology 67, no. 6 (1989): 1411–20. http://dx.doi.org/10.1139/z89-200.
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Temperature, salinity, density of Zooplankton patches, and the abundance of right whales (Eubalaena glacialis glacialis) were measured concurrently during summer and autumn of 1983 and 1984 over the Grand Manan Basin, outer Bay of Fundy. Right whales appeared to exploit patches of copepods at densities greater than about 820/m3 (170 mg m−3). Patches were composed primarily of stage V Calanus finmarchicus at depths ≥ 100 m during daylight hours. Patch densities were similar in 1983 and 1984. Potential right whale feeding areas increased in extent from late July to October, with at least two peaks of copepod biomass occurring in 1984. Right whales appear to exploit euphausiid patches in the bay only incidentally; the whales departed in 1984 when euphausiid biomass was at a maximum. The topography of the basin, prevailing summer currents, and orientation of transition zones from mixed to stratified water all combine to facilitate accumulation of copepods from the Scotian Shelf and Gulf of Maine in the central lower Bay of Fundy. This area provides an important feeding ground for this stenophagous whale species.
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Rolland, Rosalind M., Susan E. Parks, Kathleen E. Hunt, et al. "Evidence that ship noise increases stress in right whales." Proceedings of the Royal Society B: Biological Sciences 279, no. 1737 (2012): 2363–68. http://dx.doi.org/10.1098/rspb.2011.2429.
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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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Pettis, Heather M., Rosalind M. Rolland, Philip K. Hamilton, Solange Brault, Amy R. Knowlton, and Scott D. Kraus. "Visual health assessment of North Atlantic right whales (Eubalaena glacialis) using photographs." Canadian Journal of Zoology 82, no. 1 (2004): 8–19. http://dx.doi.org/10.1139/z03-207.
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Although trends in reproduction, mortality, and entanglement events have been analyzed for the endangered North Atlantic right whale (Eubalaena glacialis) population, no method has been available to assess individual right whale health. Here, we describe a technique for assessing health based on evaluation of selected physical parameters from archived photographs of right whales. A scoring system was developed to assess body and skin condition, blowhole cyamids, and rake marks in over 200 000 photographs. Comparison of body condition scores of females during calving and noncalving years found that females were significantly thinner in calving years and in the year after calving compared with the year before calving, showing that changes in body condition known to occur during the reproductive cycle can be successfully evaluated from photographs. Comparison of scores for all parameters between living whales and whales with more than a 5-year gap in sighting history ("presumed dead") found that presumed dead whales received health assessment scores indicating compromised health with body condition emerging as a key visual indicator. This health assessment method provides a new tool to monitor health trends in right whales at individual and population levels and may provide a model for assessments of other well-photographed cetaceans.
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Quintana-Rizzo, E., S. Leiter, TVN Cole, et al. "Residency, demographics, and movement patterns of North Atlantic right whales Eubalaena glacialis in an offshore wind energy development area in southern New England, USA." Endangered Species Research 45 (July 29, 2021): 251–68. http://dx.doi.org/10.3354/esr01137.
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Offshore wind energy development is growing quickly around the world. In southern New England, USA, one of the largest commercial offshore wind energy farms in the USA will be established in the waters off Massachusetts and Rhode Island, an area used by the Critically Endangered North Atlantic right whale Eubalaena glacialis. Prior to 2011, little was known about the use of this area by right whales. We examined aerial survey data collected between 2011-2015 and 2017-2019 to quantify right whale distribution, residency, demography, and movements in the region. Right whale occurrence increased during the study period. Since 2017, whales have been sighted in the area nearly every month, with peak sighting rates between late winter and spring. Model outputs suggest that 23% of the species’ population is present from December through May, and the mean residence time has tripled to an average of 13 d during these months. Age and sex ratios of the individuals present in the area are similar to those of the species as a whole, with adult males the most common demographic group. Movement models showed that southern New England is an important destination for right whales, including conceptive and reproductive females, and qualitative observations included animals feeding and socializing. Implementing mitigation procedures in coordination with these findings will be crucial in lessening the potential impacts on right whales from construction noise, increased vessel traffic, and habitat disruption in this region.
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Schaeff, Catherine M., Scott D. Kraus, Moira W. Brown, Judy S. Perkins, Roger Payne, and Bradley N. White. "Comparison of genetic variability of North and South Atlantic right whales (Eubalaena), using DNA fingerprinting." Canadian Journal of Zoology 75, no. 7 (1997): 1073–80. http://dx.doi.org/10.1139/z97-129.
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The North Atlantic right whale (Eubalaena glacialis) is the most endangered large whale in the world and shows few signs of recovery despite over 60 years of protection. In contrast, the South Atlantic right whale (E. australis), a closely related species, appears to be recovering successfully. Using DNA extracted from skin biopsy samples and two hypervariable minisatellite probes, we compared the levels of genetic diversity within the two populations. Our results revealed that unrelated North Atlantic (NA) right whales exhibit significantly less genetic variation than unrelated South Atlantic (SA) right whales (Jeffreys 33.15 (J33.15) probe: SNA-U-observed = 0.56 versus SSA-U-observed = 0.37, p < 0.01; M13 probe: SNA-U-observed = 0.74 versus SSA-U-observed = 0.46, p < 0.01). The level of band sharing among unrelated North Atlantic right whales was greater than that predicted for second-degree-related South Atlantic right whales (J33.15: SNA-U-observed = 56 versus SSA-2°-expected = 0.53, p < 0.05; M13: SNA-U-observed = 0.74 versus SSA-2°-expected = 0.60, p < 0.01), indicating that the northern animals have lost a substantial amount of genetic variability. Observed band sharing among North Atlantic first-degree relatives was lower than expected, based on band sharing among unrelated animals (J33.15: SNA-1°-observed = 0.67 versus SNA-1°-expected = 0.78, p < 0.01; M13: SNA-1°-observed = 0.83 versus SNA-1°-expected = 0.87, p = 0.15). This suggests that the matings between closely related individuals that would have resulted in the higher band-sharing values were unsuccessful. These results, in conjunction with behavioral and population data which indicate that North Atlantic right whales may be suffering from reduced fertility, fecundity, and juvenile survivorship, support the hypothesis that inbreeding depression is influencing the recovery of this species.
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Vanderlaan, Angelia S. M., R. Kent Smedbol, and Christopher T. Taggart. "Fishing-gear threat to right whales (Eubalaena glacialis) in Canadian waters and the risk of lethal entanglement." Canadian Journal of Fisheries and Aquatic Sciences 68, no. 12 (2011): 2174–93. http://dx.doi.org/10.1139/f2011-124.
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Commercial fishing gear can potentially entangle any whale, and this is especially true for the endangered North Atlantic right whale ( Eubalaena glacialis ), for which entanglement is second only to vessel strike as being responsible for documented right whale deaths. We use right whale survey data and Canadian fishing-gear deployment data to estimate the relative threat of gear entanglement in a Scotia–Fundy study area and the relative risk of lethal entanglement in the Bay of Fundy and on Roseway Basin, Scotian Shelf, where Critical Habitat has been legislated. We focus on groundfish and pelagic hook-and-line; groundfish gillnet; and crab-, hagfish-, and inshore and offshore lobster-trap gear. Our analyses demonstrate that groundfish hook-and-line gear poses the greatest threat to right whales among the seven gear types analysed during the summer-resident period in Critical Habitat and that gear from the lobster fisheries poses the greatest threat during the spring and autumn periods when whales are migrating to and from Critical Habitat. We suggest that area-specific seasonal closures of some fisheries would reduce threat and risk to whales without unduly compromising fishing interests.
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Marx, Felix G., Travis Park, Erich M. G. Fitzgerald, and Alistair R. Evans. "A Miocene pygmy right whale fossil from Australia." PeerJ 6 (June 22, 2018): e5025. http://dx.doi.org/10.7717/peerj.5025.
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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.
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Rowntree, Victoria J. "Feeding, distribution, and reproductive behavior of cyamids (Crustacea: Amphipoda) living on humpback and right whales." Canadian Journal of Zoology 74, no. 1 (1996): 103–9. http://dx.doi.org/10.1139/z96-014.
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Cyamids are little-known amphipod crustaceans that live only on cetaceans. Specimens were collected from strandings of three right whales (Eubalaena glacialis) and one humpback whale (Megaptera novaeangliae). The intestinal contents of cyamids from the humpback whale indicated that they feed on a layer of whale skin containing pigment. The single species of cyamid from the humpback whale had a male-biased sex ratio (70% male) and its distribution indicated that males were competing for access to females. Two species of cyamids from the callosities of right whales occurred in different microhabitats. No reproductive synchrony was found between cyamids and their hosts. A species of cyamid that occurs in large patches on the head of young right whale calves disappears from the head when calf growth slows at approximately 2 months of age; this habitat shift may indicate a change in the quality or quantity of new skin.
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Williams, Nigel. "Right rare whales." Current Biology 20, no. 14 (2010): R585. http://dx.doi.org/10.1016/j.cub.2010.06.062.
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Baines, Mick, and Caroline R. Weir. "Predicting suitable coastal habitat for sei whales, southern right whales and dolphins around the Falkland Islands." PLOS ONE 15, no. 12 (2020): e0244068. http://dx.doi.org/10.1371/journal.pone.0244068.
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Species distribution models (SDMs) are valuable tools for describing the occurrence of species and predicting suitable habitats. This study used generalized additive models (GAMs) and MaxEnt models to predict the relative densities of four cetacean species (sei whale Balaeanoptera borealis, southern right whale Eubalaena australis, Peale’s dolphin Lagenorhynchus australis, and Commerson’s dolphin Cephalorhynchus commersonii) in neritic waters (≤100 m depth) around the Falkland Islands, using boat survey data collected over three seasons (2017–2019). The model predictor variables (PVs) included remotely sensed environmental variables (sea surface temperature, SST, and chlorophyll-a concentration) and static geographical variables (e.g. water depth, distance to shore, slope). The GAM results explained 35 to 41% of the total deviance for sei whale, combined sei whales and unidentified large baleen whales, and Commerson’s dolphins, but only 17% of the deviance for Peale’s dolphins. The MaxEnt models for all species had low to moderate discriminatory power. The relative density of sei whales increased with SST in both models, and their predicted distribution was widespread across the inner shelf which is consistent with the use of Falklands’ waters as a coastal summer feeding ground. Peale’s dolphins and Commerson’s dolphins were largely sympatric across the study area. However, the relative densities of Commerson’s dolphins were generally predicted to be higher in nearshore, semi-enclosed, waters compared with Peale’s dolphins, suggesting some habitat partitioning. The models for southern right whales performed poorly and the results were not considered meaningful, perhaps due to this species exhibiting fewer strong habitat preferences around the Falklands. The modelling results are applicable to marine spatial planning to identify where the occurrence of cetacean species and anthropogenic activities may most overlap. Additionally, the results can inform the process of delineating a potential Key Biodiversity Area for sei whales in the Falkland Islands.
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Jackson, Jennifer A., Emma L. Carroll, Tim D. Smith, Alexandre N. Zerbini, Nathalie J. Patenaude, and C. Scott Baker. "An integrated approach to historical population assessment of the great whales: case of the New Zealand southern right whale." Royal Society Open Science 3, no. 3 (2016): 150669. http://dx.doi.org/10.1098/rsos.150669.
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Accurate estimation of historical abundance provides an essential baseline for judging the recovery of the great whales. This is particularly challenging for whales hunted prior to twentieth century modern whaling, as population-level catch records are often incomplete. Assessments of whale recovery using pre-modern exploitation indices are therefore rare, despite the intensive, global nature of nineteenth century whaling. Right whales ( Eubalaena spp.) were particularly exploited: slow swimmers with strong fidelity to sheltered calving bays, the species made predictable and easy targets. Here, we present the first integrated population-level assessment of the whaling impact and pre-exploitation abundance of a right whale, the New Zealand southern right whale ( E. australis ). In this assessment, we use a Bayesian population dynamics model integrating multiple data sources: nineteenth century catches, genetic constraints on bottleneck size and individual sightings histories informing abundance and trend. Different catch allocation scenarios are explored to account for uncertainty in the population's offshore distribution. From a pre-exploitation abundance of 28 800–47 100 whales, nineteenth century hunting reduced the population to approximately 30–40 mature females between 1914 and 1926. Today, it stands at less than 12% of pre-exploitation abundance. Despite the challenges of reconstructing historical catches and population boundaries, conservation efforts of historically exploited species benefit from targets for ecological restoration.
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Huggenberger, Stefan, Michel André, and Helmut H. A. Oelschläger. "The nose of the sperm whale: overviews of functional design, structural homologies and evolution." Journal of the Marine Biological Association of the United Kingdom 96, no. 4 (2014): 783–806. http://dx.doi.org/10.1017/s0025315414001118.
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The hypertrophic and much elongated epicranial (nasal) complex of sperm whales (Physeter macrocephalus) is a unique device to increase directionality and source levels of echolocation clicks in aquatic environments. The size and shape of the nasal fat bodies as well as the peculiar organization of the air sac system in the nasal sound generator of sperm whales are in favour of this proposed specialized acoustic function. The morphology of the sperm whale nose, including a ‘connecting acoustic window’ in the case and an anterior ‘terminal acoustic window’ at the rostroventral edge of the junk, supports the ‘bent horn hypothesis’ of sound emission. In contrast to the laryngeal mechanism described for dolphins and porpoises, sperm whales may drive the initial pulse generation process with air pressurized by nasal muscles associated with the right nasal passage (right nasal passage muscle, maxillonasolabialis muscle). This can be interpreted as an adaptation to deep-diving and high hydrostatic pressures constraining pneumatic phonation. Comparison of nasal structures in sperm whales and other toothed whales reveals that the existing air sac system as well as the fat bodies and the musculature have the same topographical relations and thus may be homologous in all toothed whales (Odontoceti). This implies that the nasal sound generating system evolved only once during toothed whale evolution and, more specifically, that the unique hypertrophied nasal complex was a main driving force in the evolution of the sperm whale taxon.
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Schick, Robert S., Patrick N. Halpin, Andrew J. Read, et al. "Striking the right balance in right whale conservation." Canadian Journal of Fisheries and Aquatic Sciences 66, no. 9 (2009): 1399–403. http://dx.doi.org/10.1139/f09-115.
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Despite many years of study and protection, the North Atlantic right whale ( Eubalaena glacialis ) remains on the brink of extinction. There is a crucial gap in our understanding of their habitat use in the migratory corridor along the eastern seaboard of the United States. Here, we characterize habitat suitability in migrating right whales in relation to depth, distance to shore, and the recently enacted ship speed regulations near major ports. We find that the range of suitable habitat exceeds previous estimates and that, as compared with the enacted 20 nautical mile buffer, the originally proposed 30 nautical mile buffer would protect more habitat for this critically endangered species.
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Parks, Susan E., Dana A. Cusano, Sofie M. Van Parijs, and Douglas P. Nowacek. "Acoustic crypsis in communication by North Atlantic right whale mother–calf pairs on the calving grounds." Biology Letters 15, no. 10 (2019): 20190485. http://dx.doi.org/10.1098/rsbl.2019.0485.
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Mammals with dependent young often rely on cryptic behaviour to avoid detection by potential predators. In the mysticetes, large baleen whales, young calves are known to be vulnerable to direct predation from both shark and orca predators; therefore, it is possible that mother–calf pairs may show cryptic behaviours to avoid the attention of predators. Baleen whales primarily communicate through low-frequency acoustic signals, which can travel over long ranges. In this study, we explore the potential for acoustic crypsis, a form of cryptic behaviour to avoid predator detection, in North Atlantic right whale mother–calf pairs. We predicted that mother–calf pairs would either show reduced calling rates, reduced call amplitude or a combination of these behavioural modifications when compared with other demographic groups in the same habitat. Our results show that right whale mother–calf pairs have a strong shift in repertoire usage, significantly reducing the number of higher amplitude, long-distance communication signals they produced when compared with juvenile and pregnant whales in the same habitat. These observations show that right whale mother–calf pairs rely upon acoustic crypsis, potentially to minimize the risk of acoustic eavesdropping by predators.
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Figueiredo, Giovanna Corrêa e., Samara Cazzoli y. Goya, and Marcos César de Oliveira Santos. "Southern right whales in the South-western Atlantic Ocean: proposed criteria to identify suitable areas of use in poorly known reproductive grounds." Journal of the Marine Biological Association of the United Kingdom 99, no. 5 (2019): 1231–36. http://dx.doi.org/10.1017/s0025315418001042.
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AbstractUrbanization and intense vessel traffic in coastal areas are obstacles for right whales when selecting breeding and calving grounds. Human activities might be the main cause for the recently observed drop in right whale sightings along the south-eastern coast of Brazil. Information concerning the biology and the activities that can potentially affect the presence of individuals along the coast are essential for management purposes, as well as for the recovery of the species stocks after a period of whaling pressure. This study correlated the occurrence of right whales in the northern limit of the breeding ground in the South-western Atlantic Ocean with local geomorphology, degree of urbanization and oceanographic features to better identify suitable areas for use by these whales. The study area was divided into 14 sub-areas based on local coastal geomorphology and discharge of large rivers. The following five ranking criteria were applied to each sub-area: presence of whaling stations and whaling activity in the past; presence and activity of ports; protection from swell, coastal slope and composition of the bottom substrate. The sub-areas that offered conditions conducive to the presence of right whales received higher scores. The proposed criteria were validated by overlapping the ranking scores with the records of right whales sighted in each sub-area. In south-eastern Brazil, protected areas with sandy bottom and gentle slope were associated with more sightings of female-calf pairs. The criteria can be used as a primary diagnostic indicating suitable sub-areas for right whales in poorly known breeding grounds.
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Pershing, Andrew, and Daniel Pendleton. "Can Right Whales Out-Swim Climate Change? Can We?" Oceanography 34, no. 3 (2021): 19–21. http://dx.doi.org/10.5670/oceanog.2021.315.
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The article by Meyer-Gutbrod and colleagues in this issue demonstrates that the endangered North Atlantic right whale’s preferred prey has declined as the Northwest Atlantic has warmed. Right whales are now spending more time foraging in historically colder habitats, but they are producing fewer calves. The low calf production could reflect a delay between the decline in the potential productivity of their traditional habitats and its increase in their new habitats. This delay would result in a “climate deficit” in their fitness. Right whales must also learn to forage successfully in their new habitats, creating an additional loss of fitness termed an “adaptation deficit.” Humans will also face unavoidable climate deficits, but we have more options for minimizing adaptation deficits.
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Silber, Gregory K., Michael W. Newcomer, and Héctor Pérez-Cortés M. "Killer whales (Orcinus orca) attack and kill a Bryde's whale (Balaenoptera edeni)." Canadian Journal of Zoology 68, no. 7 (1990): 1603–6. http://dx.doi.org/10.1139/z90-238.
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On 3 May 1988, we observed a group of killer whales that pursued, killed, and partially consumed a Bryde's whale in the northern Gulf of California, Mexico (31°01′N, 114°15′W). The attack was observed from 06:54 to 08:53 while circling in a single-engine aircraft at an altitude of 160 m. The group comprised about 15 killer whales, including two adult males and at least two calves. Females and (or) subadult males pressed the attack most intently. The killer whales tore skin and blubber from the right flank of the Bryde's whale, and on 11 occasions the killer whales swam onto the head or back of the Bryde's whale, which hindered its breathing. The respiration intervals of the Bryde's whale were short and irregular, and blow rates differed significantly from those of undisturbed Bryde's whales. Fatiguing the whale may have facilitated an easier kill by asphyxiation. After the death of the Bryde's whale, the two adult male killer whales surfaced slowly about 200–300 m away from the remainder of the group, which presumably fed on the submerged Bryde's whale carcass. Two days later, the drifting Bryde's whale carcass was located. A large wound was visible on the abdomen, and sections of the lower jaw had been removed. Like those of canids and some felids that hunt cooperatively when preying on ungulates, attacks by Orcinus orca exhibit coordination of activities and efficiency in dispatching prey.
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Baumgartner, Mark F., and Bruce R. Mate. "Summer and fall habitat of North Atlantic right whales (Eubalaena glacialis) inferred from satellite telemetry." Canadian Journal of Fisheries and Aquatic Sciences 62, no. 3 (2005): 527–43. http://dx.doi.org/10.1139/f04-238.
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Satellite-monitored radio tags were attached to North Atlantic right whales (Eubalaena glacialis) in Grand Manan Basin of the lower Bay of Fundy during the summer and early fall seasons of 19891991 and 2000. Monte Carlo tests were used to examine the distribution of the tagged whales in space and time and with respect to a variety of environmental variables to characterize right whale habitat on their northern feeding grounds. These environmental variables included depth, depth gradient, climatological surface and bottom hydrographic properties, and remotely sensed surface temperature, chlorophyll concentration, and their respective horizontal gradients. Site fidelity in the Bay of Fundy was very low during 19891991 and high during 2000. When the tagged animals left the Bay, they did not frequently visit the deep basins of the Gulf of Maine and Scotian Shelf, where abundances of their primary copepod prey, Calanus finmarchicus, are thought to be high. Instead, right whales visited areas characterized by low bottom water temperatures, high surface salinity, and high surface stratification. No evidence was found that the tagged right whales associated with oceanic fronts or regions with high standing stocks of phytoplankton.
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Meyer-Gutbrod, Erin, Charles Greene, Kimberley Davies, and David Johns. "Ocean Regime Shift is Driving Collapse of the North Atlantic Right Whale Population." Oceanography 34, no. 3 (2021): 22–31. http://dx.doi.org/10.5670/oceanog.2021.308.
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Ocean warming linked to anthropogenic climate change is impacting the ecology of marine species around the world. In 2010, the Gulf of Maine and Scotian Shelf regions of the Northwest Atlantic underwent an unprecedented regime shift. Forced by climate-driven changes in the Gulf Stream, warm slope waters entered the region and created a less favorable foraging environment for the endangered North Atlantic right whale population. By mid-decade, right whales had shifted their late spring/summer foraging grounds from the Gulf of Maine and the western Scotian Shelf to the Gulf of St. Lawrence. The population also began exhibiting unusually high mortality in 2017. Here, we report that climate-driven changes in ocean circulation have altered the foraging environment and habitat use of right whales, reducing the population’s calving rate and exposing it to greater mortality risks from ship strikes and fishing gear entanglement. The case of the North Atlantic right whale provides a cautionary tale for the management of protected species in a changing ocean.
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Fordyce, R. Ewan, and Felix G. Marx. "The pygmy right whale Caperea marginata : the last of the cetotheres." Proceedings of the Royal Society B: Biological Sciences 280, no. 1753 (2013): 20122645. http://dx.doi.org/10.1098/rspb.2012.2645.
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The pygmy right whale, Caperea marginata , is the most enigmatic of the living baleen whales (Mysticeti). Its highly disparate morphology and the virtual absence of a described fossil record have made it extremely difficult to place Caperea into a broader evolutionary context, and molecular and morphological studies have frequently contradicted each other as to the origins and phylogenetic relationships of the species. Our study of a wealth of material from New Zealand collections, representing a wide range of ontogenetic stages, has identified several new features previously unreported in Caperea , which suggest that the pygmy right whale may be the last survivor of the supposedly extinct family Cetotheriidae. This hypothesis is corroborated by both morphology-based and total evidence cladistic analyses, including 166 morphological characters and 23 taxa, representing all the living and extinct families of toothless baleen whales. Our results allow us to formally refer Caperea to Cetotheriidae, thus resurrecting the latter from extinction and helping to clarify the origins of a long-problematic living species.
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Stamation, K., M. Watson, P. Moloney, C. Charlton, and J. Bannister. "Population estimate and rate of increase of southern right whales Eubalaena australis in southeastern Australia." Endangered Species Research 41 (April 30, 2020): 373–83. http://dx.doi.org/10.3354/esr01031.
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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.
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Watson, Mandy, Kasey Stamation, and Claire Charlton. "Calving rates, long-range movements and site fidelity of southern right whales (Eubalaena australis) in south-eastern Australia." J. Cetacean Res. Manage. 22, no. 1 (2021): 17–28. http://dx.doi.org/10.47536/jcrm.v22i1.210.
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Within New Zealand and eastern Australia, over 58,000 southern right whales were harvested by commercial whalers between 1790 and 1980, with approximately 19,000 harvested from south-eastern Australia. Local extirpation is believed to have led to a loss of cultural memory of calving areas, contributing to the limited recovery of the south-eastern Australian population. While the number of whales observed using the south-eastern Australian coastline is increasing, there has been no change over three decades in the annual abundance of cow-calf pairs at Logans Beach in Warrnambool, Victoria, the only established calving ground in the region. Knowledge of life history parameters of the south-eastern Australian population is lacking. Here, we examine sightings and photo-identification data from southern Australia to investigate calving intervals, long range movements and fidelity to the Logans Beach nursery ground. Sightings data revealed at least 93 calves were born at Logans Beach between 1980 and 2018 (an average of 2.6 per year) with a mean calving interval of 3.5 ± 1.0 years (± SE, n = 34). Comparison between photo-identification catalogues compiled for south-eastern and south-western Australian populations shows that southern right whales are wide ranging within southern Australian waters. Females can be sighted at locations as far apart as 3,800 km across seasons and there is overlap in the wintering range of the south-eastern and south-western populations, with at least 7% of whales using both regions. We also provide the first report of an Australian southern right whale female with strong site fidelity to a calving area in one region relocating long-term to a calving area in another region. This work highlights several knowledge gaps, such as; the location of feeding and conception grounds for this population as well as the degree of mixing between the two Australian populations outside their wintering areas. In addition, the proportion of female calves born at Logans Beach returning to their natal site to calve remains unclear. Our work provides the first assessment of calving rates, movement and site fidelity within the south-eastern Australian population, critical for understanding constraints to recovery and informing conservation management of southern right whales in Australia. Targeted, long-term monitoring programs across the south-eastern Australian region are needed to provide demographic information on which to base predictions of the impacts of anthropogenic threats such as noise disturbance, entanglement and vessel strike.
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Sironi, Mariano, Lucía Alzugaray, Agustina Saez, Florencia Ornela Vilches, Alejandro Fernández Ajó, and Paula Faiferman. "The use of underwater viewing deck of the semi-submersible whalewatching vessel Yellow Submarine at Península Valdés, Argentina as a platform of opportunity for scientifc research with the southern right whale, Eubalaena australis." Latin American Journal of Aquatic Mammals 13, no. 1-2 (2019): 2–8. http://dx.doi.org/10.5597/00242.
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Whale-watching vessels can be used as platforms to collect scientific data on the natural history of cetaceans. Vessels with underwater viewing decks are exceptional and offer a unique view of the whales. We assessed the underwater viewing platform of the semi-submersible vessel Yellow Submarine that operates off Puerto Pirámides, Península Valdés, Argentina as a platform of opportunity for southern right whale (Eubalaena australis) research. The variables considered during observations included, among others, the age class and sex of the animals observed, behavioral patterns, opportunities for individual photo-identification, distance and duration of the underwater observations and how weather conditions affected data collection. The Yellow Submarine offers a unique platform to make underwater observations of southern right whales in this calving ground. The main limitations are the relatively short duration of the observations and reduced visibility in spring.
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Jackson, JA, A. Kennedy, M. Moore, et al. "Have whales returned to a historical hotspot of industrial whaling? The pattern of southern right whale Eubalaena australis recovery at South Georgia." Endangered Species Research 43 (November 5, 2020): 323–39. http://dx.doi.org/10.3354/esr01072.
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Around 176500 whales were killed in the sub-Antarctic waters off South Georgia (South Atlantic) between 1904 and 1965. In recent decades, whales have once again become summer visitors, with the southern right whale (SRW) the most commonly reported species until 2011. Here, we assess the distribution, temporal pattern, health status and likely prey of SRWs in these waters, combining observations from a summertime vessel-based expedition to South Georgia, stable isotope data collected from SRWs and putative prey and sightings reports collated by the South Georgia Museum. The expedition used directional acoustics and visual surveys to localise whales and collected skin biopsies and photo-IDs. During 76 h of visual observation effort over 19 expedition days, SRWs were encountered 15 times (~31 individuals). Photo-IDs, combined with publicly contributed images from commercial vessels, were reconciled and quality-controlled to form a catalogue of 6 fully (i.e. both sides) identified SRWs and 26 SRWs identified by either left or right sides. No photo-ID matches were found with lower-latitude calving grounds, but 3 whales had gull lesions supporting a direct link with Península Valdés, Argentina. The isotopic position of SRWs in the South Georgia food web suggests feeding on a combination of copepod and krill species. Opportunistic reports of SRW sightings and associated group sizes remain steady over time, while humpback whales provide a strong contrast, with increased sighting rates and group sizes seen since 2013. These data suggest a plateau in SRWs and an increasing humpback whale presence in South Georgia waters following the cessation of whaling.
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de Oliveira, Larissa Rosa, Paulo Henrique Ott, Paulo A. C. Flores, Salvatore Siciliano, Raquel Santos de Almeida, and Sandro L. Bonatto. "First molecular estimate of sex-ratio of southern right whale calves, Eubalaena australis, for Brazilian waters." Journal of the Marine Biological Association of the United Kingdom 89, no. 5 (2009): 1003–7. http://dx.doi.org/10.1017/s0025315409003178.
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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.
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Fretwell, Peter T., Iain J. Staniland, and Jaume Forcada. "Whales from Space: Counting Southern Right Whales by Satellite." PLoS ONE 9, no. 2 (2014): e88655. http://dx.doi.org/10.1371/journal.pone.0088655.
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Webster, T. A., S. M. Van Parijs, W. J. Rayment, and S. M. Dawson. "Temporal variation in the vocal behaviour of southern right whales in the Auckland Islands, New Zealand." Royal Society Open Science 6, no. 3 (2019): 181487. http://dx.doi.org/10.1098/rsos.181487.
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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.
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Sayles, J. S. "Bilateral Action for Right Whales." Science 310, no. 5754 (2005): 1616–18. http://dx.doi.org/10.1126/science.310.5754.1616.
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Tehhune, J. M., and W. C. Verboom. "Right Whales and Ship Noises." Marine Mammal Science 15, no. 1 (1999): 256–58. http://dx.doi.org/10.1111/j.1748-7692.1999.tb00799.x.
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Parks, Susan E., Douglas P. Nowacek, Mark P. Johnson, and Peter L. Tyack. "Right whales—Social sound production." Journal of the Acoustical Society of America 119, no. 5 (2006): 3402–3. http://dx.doi.org/10.1121/1.4786752.
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Weinrich, Mason. "The Urban Whale: North Atlantic Right Whales at the Crossroads." Marine Technology Society Journal 41, no. 1 (2007): 94. http://dx.doi.org/10.4031/002533207787442385.
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Simard, Peter, Jennifer L. Lawlor, and Shannon Gowans. "Temporal Variability of Cetaceans near Halifax, Nova Scotia." Canadian Field-Naturalist 120, no. 1 (2006): 93. http://dx.doi.org/10.22621/cfn.v120i1.252.
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Annual and seasonal trends in sightings of coastal cetaceans near Halifax, Nova Scotia, were studied using observations from whale watching and dedicated research vessels from late spring to early fall of 1996 to 2005. Four species of cetaceans routinely used the area during the summer: White-beaked and Atlantic White-sided dolphins (Lagenorhynchus albirostris and L. acutus), Harbour Porpoises (Phocoena phocoena), and Minke Whales (Balaenoptera acutorostrata). The dolphin species were temporally separated, with White-beaked Dolphins being common earlier in the summer than White-sided Dolphins. White-sided Dolphins were unusually abundant in 1997, and were found in larger groups (mean = 46.5 ± 46.19 sd) than Whitebeaked Dolphins (mean = 9.1 ± 5.19 SD). The area also appears to be an important habitat for dolphin calves and juveniles of both species. Fin Whales (B. physalus) were commonly observed in relatively large groups in 1997, but were uncommon or absent in other years. Humpback Whales (Megaptera novaeangliae), Blue Whales (B. musculus) and North Atlantic Right Whales (Eubalaena glacialis) were uncommon in the area, although Humpback Whales were sighted frequently in 1997. Increased numbers of White-sided Dolphins, Fin and Humpback whales in 1997 may be explained by increased prey abundance and decreased sea-surface temperatures.
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Record, Nicholas. "The Intertwined Futures of Whales and Humans." Oceanography 34, no. 3 (2021): 16–18. http://dx.doi.org/10.5670/oceanog.2021.314.
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If you could somehow ask a North Atlantic right whale what she thinks the future holds, what would she say? Right whales must, in some way, think about the future in order to make survival decisions. As an ocean science community, our eyes are trained increasingly on the future as well. The twin global environmental crises of climate change and biodiversity loss have elevated the science of real-world prediction to one of urgent interest. At timescales ranging from hours to decades, society is asking ocean science for actionable predictions, projections, and forecasts, with the hope of mitigating and adapting to the changing ocean. Meeting this challenge requires more than the ability to predict ocean dynamics.
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Tsai, Cheng-Hsiu, and R. Ewan Fordyce. "Ancestor–descendant relationships in evolution: origin of the extant pygmy right whale, Caperea marginata." Biology Letters 11, no. 1 (2015): 20140875. http://dx.doi.org/10.1098/rsbl.2014.0875.
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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.
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Bisconti, Michelangelo, Luca Pellegrino, and Giorgio Carnevale. "Evolution of gigantism in right and bowhead whales (Cetacea: Mysticeti: Balaenidae)." Biological Journal of the Linnean Society 134, no. 2 (2021): 498–524. http://dx.doi.org/10.1093/biolinnean/blab086.
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Abstract The evolution of gigantic body size represents a key to understand the ecological role of baleen whales in oceanic ecosystems. Many efforts have been devoted to the formulation of equations relating different body parts to total body length and mass in living and fossil mysticetes, mainly focusing on balaenopterid and balaenopterid-like mysticetes. Right whales (family Balaenidae) have a unique head-to-body length ratio, suggesting that their body proportions cannot be predicted effectively using equations based primarily on non-balaenid mysticetes. A new morphometric dataset of living and fossil balaenids is provided herein, and new regression equations allow one to predict the body length and mass of extinct species based on the expected head-to-body length ratio of extant balaenids. The reconstructed values are mapped on a new phylogenetic analysis of the Balaenidae, inferring body size and mass at ancestral nodes. The variations of body size and mass in Balaenidae since the early Miocene are reconstructed, revealing that: (1) a reduction in total body length occurred in the early Pliocene; (2) the origin of the gigantic body size in the bowhead whale (Balaena mysticetus) is probably related to invasion of the Arctic Ocean in the last 3 Myr; and (3) the origin of the gigantic body size in the right whales (genus Eubalaena) occurred since the latest Miocene, probably concomitant with pulses of nutrients sustaining large zooplankton populations. We suggest that the evolution of gigantism in Balaenidae occurred independently in two lineages and, probably, in response to different palaeoenvironmental drivers.
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Parks, Susan E., Mark Johnson, Douglas Nowacek, and Peter L. Tyack. "Individual right whales call louder in increased environmental noise." Biology Letters 7, no. 1 (2010): 33–35. http://dx.doi.org/10.1098/rsbl.2010.0451.
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The ability to modify vocalizations to compensate for environmental noise is critical for successful communication in a dynamic acoustic environment. Many marine species rely on sound for vital life functions including communication, navigation and feeding. The impacts of significant increases in ocean noise levels from human activities are a current area of concern for the conservation of marine mammals. Here, we document changes in calling behaviour by individual endangered North Atlantic right whales ( Eubalaena glacialis ) in increased background noise. Right whales, like several bird and primate species, respond to periods of increased noise by increasing the amplitude of their calls. This behaviour may help maintain the communication range with conspecifics during periods of increased noise. These call modifications have implications for conservation efforts for right whales, affecting both the way whales use sound to communicate and our ability to detect them with passive acoustic monitoring systems.
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Paxton, C. G. M., E. Knatterud, and S. L. Hedley. "Cetaceans, sex and sea serpents: an analysis of the Egede accounts of a “most dreadful monster” seen off the coast of Greenland in 1734." Archives of Natural History 32, no. 1 (2005): 1–9. http://dx.doi.org/10.3366/anh.2005.32.1.1.
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A re-evaluation of the “most dreadful monster” originally described by the “Apostle of Greenland” Hans Egede in 1741 suggests that the missionary's son Poul probably saw an unfamiliar cetacean. The species seen was likely to have been a humpback whale (Megaptera novaeangliae), a North Atlantic right whale (Eubalaena glacialis) or one of the last remaining Atlantic grey whales (Eschrichtius robustus) either without flukes or possibly a male in a state of arousal.
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Purdon, Jean, Fannie W. Shabangu, Dawit Yemane, Marc Pienaar, Michael J. Somers, and Ken Findlay. "Species distribution modelling of Bryde’s whales, humpback whales, southern right whales, and sperm whales in the southern African region to inform their conservation in expanding economies." PeerJ 8 (September 22, 2020): e9997. http://dx.doi.org/10.7717/peerj.9997.
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In southern African waters, information about species distribution and habitat preferences of many cetacean species is limited, despite the recent economic growth that may affect them. We determined the relative importance of eight environmental variables (bathymetry, distance to shore, slope, chlorophyll-a, salinity, eastwards sea water velocity, northwards sea water velocity and sea surface temperature) as drivers of seasonal habitat preferences of Bryde’s whales (Balaenoptera brydei), humpback whales (Megaptera novaeangliae), southern right whales (Eubalaena australis) and sperm whales (Physeter macrocephalus). Using presence only data from multiple sources, we constructed predictive species distribution models (SDMs) consisting of ensembles of seven algorithms for these species during both summer and winter. Predicted distribution for all cetaceans was high in southern Africa and, in particular, within the South African Exclusive Economic Zone (EEZ). Predictive models indicated a more pronounced seasonal variation for humpback, sperm and southern right whales than for Bryde’s whales. Southern right whales occurred closer to shore during winter, humpback whales were more likely to occur along the east coast in winter and the west coast in summer, and sperm whales were more concentrated off the shelf in winter. Our study shows that ensemble models using historical, incidental and scientific data, in conjunction with modern environmental variables, can provide baseline knowledge on important environmental drivers of cetacean distribution for conservation purposes. Results of this study can further be used to help develop marine spatial plans and identify important marine mammal areas.
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D'Amato, Anthony, and Sudhir K. Chopra. "Whales: Their Emerging Right to Life." American Journal of International Law 85, no. 1 (1991): 21. http://dx.doi.org/10.2307/2203557.
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Hamilton, Philip K., Marilyn K. Marx, and Sctxr D. Kraus. "WEANING IN NORTH ATLANTIC RIGHT WHALES." Marine Mammal Science 11, no. 3 (1995): 386–90. http://dx.doi.org/10.1111/j.1748-7692.1995.tb00293.x.
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