Industrial Whaling Research Articles

Density dependence only affects increase rates in baleen whale populations at high abundance levels

Abstract Most baleen whale populations are increasing after the end of industrial whaling, but their recovery patterns challenge long‐standing assumptions about density dependence. It has long been assumed that population growth rates will decline with recovery, until reaching equilibrium (‘carrying capacity’, K). Indeed, the International Whaling Commission assumes that growth rates will slow long before K is reached, with maximum productivity at 0.6K. This 0.6K population level is used as an international benchmark that forms the basis of whaling regulations and decisions about whether baleen whale populations are declared depleted. We fit models to four long‐term data sets for baleen whales with multiple abundance estimates that span the range from low to high abundance, finding strong evidence that increase rates remain at near‐maximal levels across a wide range of abundance levels, and only decline as the population nears K. As a result, maximum productivity occurs at 0.69–0.87 of K across these populations, which predicts more rapid recovery for baleen whale populations than currently assumed. The overall mean of these values (0.8K) would be a more sensible default choice than the 0.6K currently assumed. Synthesis and applications. Estimated recovery rates imply that management thresholds currently used are lower than actual maximum productivity and that populations can increase rapidly even at high abundance. However, if population models continue to assume that maximum productivity is at 0.6K, they will estimate abundance relative to K to be lower than it is, providing conservative assessment results. Our results should stimulate further discussion about the role of maximum sustainable yield as a fundamental concept in fisheries and wildlife management.

Antarctic sonobuoy surveys for blue whales from 2006-2021 reveal contemporary distribution, changes over time, and paths to further our understanding of their distribution and biology

Seven passive acoustic surveys for marine mammal sounds were conducted by deploying sonobuoys along ship tracks during Antarctic voyages spanning years 2006-2021. These surveys included nearly 330° of longitude throughout Antarctic (south of 60°S) and sub-Antarctic (between 50-60°S) latitudes. Here, we summarise the presence of calls from critically endangered Antarctic blue whales (Balaenoptera musculus intermedia) detected on all seven of these surveys. We describe and compare the spatial distribution of detections of three different types of Antarctic blue whale calls: unit-A, Z-calls, and D-calls. Three sets of voyages partially overlapped spatially but in different years, providing three regions (Indian Sector, Dumont d’Urville Sea, Ross Sea) to investigate differences over time for these three different call types. The proportion of sonobuoys with calls present was significantly higher in the more recent years for seven of the 15 combinations of years, regions, and call type. The proportion of sonobuoys with calls present was significantly lower only for one of the 15 combinations (unit A in the Ross Sea between 2015 vs 2017), and not significantly different for the remaining seven pairwise comparisons. We discuss possible explanations for these observations including: differences in probability of detection, whale behaviour, whale distribution, and abundance. These explanations are not mutually exclusive and cannot yet be resolved without application of complex analytical methods and collection of additional data. Lastly, we discuss future work that could help clarify the contributions of each of these potential drivers of acoustic detection. We propose continued acoustic data collection, application of new analytical methods, and collection of other synergistic data from Antarctic blue whales on their feeding grounds as a basis for future work on this species. This could provide a cost effective and holistic means of monitoring their status after the effects of 20th century industrial whaling, as well as their responses to natural and anthropogenic changes to their main prey, Antarctic krill, and a changing climate.

The genomic footprint of whaling and isolation in fin whale populations

Twentieth century industrial whaling pushed several species to the brink of extinction, with fin whales being the most impacted. However, a small, resident population in the Gulf of California was not targeted by whaling. Here, we analyzed 50 whole-genomes from the Eastern North Pacific (ENP) and Gulf of California (GOC) fin whale populations to investigate their demographic history and the genomic effects of natural and human-induced bottlenecks. We show that the two populations diverged ~16,000 years ago, after which the ENP population expanded and then suffered a 99% reduction in effective size during the whaling period. In contrast, the GOC population remained small and isolated, receiving less than one migrant per generation. However, this low level of migration has been crucial for maintaining its viability. Our study exposes the severity of whaling, emphasizes the importance of migration, and demonstrates the use of genome-based analyses and simulations to inform conservation strategies.

The prelude to industrial whaling: identifying the targets of ancient European whaling using zooarchaeology and collagen mass-peptide fingerprinting.

Taxonomic identification of whale bones found during archaeological excavations is problematic due to their typically fragmented state. This difficulty limits understanding of both the past spatio-temporal distributions of whale populations and of possible early whaling activities. To overcome this challenge, we performed zooarchaeology by mass spectrometry on an unprecedented 719 archaeological and palaeontological specimens of probable whale bone from Atlantic European contexts, predominantly dating from ca 3500 BCE to the eighteenth century CE. The results show high numbers of Balaenidae (many probably North Atlantic right whale (Eubalaena glacialis)) and grey whale (Eschrichtius robustus) specimens, two taxa no longer present in the eastern North Atlantic. This discovery matches expectations regarding the past utilization of North Atlantic right whales, but was unanticipated for grey whales, which have hitherto rarely been identified in the European zooarchaeological record. Many of these specimens derive from contexts associated with mediaeval cultures frequently linked to whaling: the Basques, northern Spaniards, Normans, Flemish, Frisians, Anglo-Saxons and Scandinavians. This association raises the likelihood that early whaling impacted these taxa, contributing to their extirpation and extinction. Much lower numbers of other large cetacean taxa were identified, suggesting that what are now the most depleted whales were once those most frequently used.

Commercial krill fishing within a foraging supergroup of fin whales in the Southern Ocean.

Commercial krill fishing within a foraging supergroup of fin whales in the Southern Ocean.

Identifying seasonal distribution patterns of fin whales across the Scotia Sea and the Antarctic Peninsula region using a novel approach combining habitat suitability models and ensemble learning methods

Following their near extirpation by industrial whaling of the 20thcentury, the population status of Southern Hemisphere fin whales (SHFW) remains unknown. Systematic surveys estimating fin whale abundance in the Southern Ocean are not yet available. Records of fin whale sightings have been collected by a variety of organisations over the past few decades, incorporating both opportunistic data and dedicated survey data. Together, these isolated data sets represent a potentially valuable source of information on the seasonality, distribution and abundance of SHFW. We compiled records across 40 years from the Antarctic Peninsula and Scotia Sea from multiple sources and used a novel approach combining ensemble learning and a maximum entropy model to estimate abundance and distribution of SHFW in this region. Our results show a seasonal distribution pattern with pronounced centres of distribution from January-March along the West Antarctic Peninsula. Our new approach allowed us to estimate abundance of SHFW for discrete areas from a mixed data set of mainly opportunistic presence only data.

First evidence for fin whale migration into the Pacific from Antarctic feeding grounds at Elephant Island.

This study presents the first long-distance tracks of fin whales (Balaenoptera physalus) equipped with satellite transmitters off the Antarctic Peninsula. Southern Hemisphere fin whales were severely depleted by twentieth century industrial whaling, yet recently, they have returned to historical feeding grounds off the northern Antarctic Peninsula, forming large aggregations in austral summers. To date, our knowledge only extended to summer behaviour, while information regarding migration routes and the location of breeding and wintering grounds are lacking. During the austral autumn of 2021, we deployed nsatellite transmitters on four fin whales at Elephant Island. Two transmitters stopped working while the animals were still at the feeding grounds, while two continued to transmit during the transition from feeding activity to migration. Both migrating animals left the feeding ground on 15 April 2021, travelling northward into the Pacific and up along the Chilean coast. The most northerly position received before all tags stopped transmitting on 1 May 2021 was at 48°S. These tracks provide initial evidence of seasonal migratory routes and a first indication toward possible locations of winter destinations. This information, even if preliminary, is critical for investigations of population connectivity, population structure and the identification of breeding grounds of Southern Hemisphere fin whales.

Return of large fin whale feeding aggregations to historical whaling grounds in the Southern Ocean

Fin whales (Balaenoptera physalus quoyi) of the Southern Hemisphere were brought to near extinction by twentieth century industrial whaling. For decades, they had all but disappeared from previously highly frequented feeding grounds in Antarctic waters. Our dedicated surveys now confirm their return to ancestral feeding grounds, gathering at the Antarctic Peninsula in large aggregations to feed. We report on the results of an abundance survey and present the first scientific documentation of large fin whale feeding aggregations at Elephant Island, Antarctica, including the first ever video documentation. We interpret high densities, re-establishment of historical behaviours and the return to ancestral feeding grounds as signs for a recovering population. Recovery of a large whale population has the potential to augment primary productivity at their feeding grounds through the effects of nutrient recycling, known as 'the whale pump'. The recovery of fin whales in that area could thus restore ecosystem functions crucial for atmospheric carbon regulation in the world's most important ocean region for the uptake of anthropogenic CO2.

Endangered Blue Whale Survival in the North Atlantic: Lagging Scientific and Governance Responses, Charting Future Courses

Abstract Populations of blue whales were heavily depleted across the globe by industrial whaling and are still considered globally endangered today. In the Northwest Atlantic, an estimated 400–600 individuals remain, but these numbers are highly uncertain. Ship strikes, fishing gear entanglement, and marine debris are thought to be leading causes of contemporary human-caused mortality in blue whales, with anthropogenic noise possibly causing sublethal stress and injury. Climate change is recognised as an emerging and intensifying threat that is likely to affect food supply and could limit the capacity of the population to recover. Both Canada and the United States have protected blue whales through their domestic legislation. This article reviews law and policy responses in the two countries, as well as bilateral, regional and international frameworks that address anthropogenic threats to blue whales. Future scientific directions, as well as recommendations for improvements to domestic legislation and multilevel cooperation are outlined.

Have whales returned to a historical hotspot of industrial whaling? The pattern of southern right whale Eubalaena australis recovery at South Georgia

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.

Bill Dawbin, Tasman Diplomacy, and the Great South Pacific Humpback Collapse of 1959–62

ABSTRACT The history of industrial whaling in Oceania, along with crucial moments in the diplomatic histories of Australia and New Zealand, sometimes turned on questions of whale behaviour. So did individual human lives. This article puts together the histories of whale communities and the history of cetacean science in order to unravel the meaning of some key moments in the environmental history of the South Pacific, including Oceanian attempts to increase their share of post-war whaling and the subsequent great humpback whale collapse of 1960–62. In the middle of these histories were the efforts of cetologist Bill Dawbin to understand humpback whale migrations in the late 1950s. Interwoven throughout was the crucial fact of humpback whales’ historical split into several different populations and their migratory choices, and the difficulties humans face in understanding these complex and mobile creatures.

Bringing fish to the shore: fishermen’s knowledge and the anti-whaling protests in Norway and Japan, 1900–12

AbstractThis article discusses the largely forgotten anti-whaling protests in Norway and Japan at the beginning of the twentieth century. It shows that fishing communities around the world protested almost simultaneously against the introduction of Norwegian-style industrial whaling, even though the protesting fishermen did not compete for the same marine resources as the whalers. Analysing Norwegian and Japanese fishermen’s knowledge reveals that whales played a crucial part in pre-industrial coastal fishing, as they were partly responsible for bringing fish closer to the shore. The article argues that fishing communities around the world had developed ‘coeval moral ecologies’, believing that the killing and flensing of whales caused environmental pollution, hurting coastal flora and fauna, and thus ultimately diminishing the coastal ecosystem on which the fishing communities depended. Fisheries scientists, politicians, and whalers have, however, downplayed this fishermen’s knowledge by presenting allegedly unbiased scientific data that did not indicate a relationship between whaling and fishing.

South Georgia blue whales five decades after the end of whaling

Blue whalesBalaenoptera musculusat South Georgia were heavily exploited during 20thcentury industrial whaling, to the point of local near-extirpation. Although legal whaling for blue whales ceased in the 1960s, and there were indications of blue whale recovery across the wider Southern Ocean area, blue whales were seldom seen in South Georgia waters in subsequent years. We collated 30 yr of data comprising opportunistic sightings, systematic visual and acoustic surveys and photo-identification to assess the current distribution of blue whales in the waters surrounding South Georgia. Over 34000 km of systematic survey data between 1998 and 2018 resulted in only a single blue whale sighting, although opportunistic sightings were reported over that time period. However, since 2018 there have been increases in both sightings of blue whales and detections of their vocalisations. A survey in 2020 comprising visual line transect surveys and directional frequency analysis and recording (DIFAR) sonobuoy deployments resulted in 58 blue whale sightings from 2430 km of visual effort, including the photo-identification of 23 individual blue whales. Blue whale vocalisations were detected on all 31 sonobuoys deployed (114 h). In total, 41 blue whales were photo-identified from South Georgia between 2011 and 2020, none of which matched the 517 whales in the current Antarctic catalogue. These recent data suggest that blue whales have started to return to South Georgia waters, but continued visual and acoustic surveys are required to monitor any future changes in their distribution and abundance.

Baleen whale cortisol levels reveal a physiological response to 20th century whaling

One of the most important challenges researchers and managers confront in conservation ecology is predicting a population’s response to sub-lethal stressors. Such predictions have been particularly elusive when assessing responses of large marine mammals to past anthropogenic pressures. Recently developed techniques involving baleen whale earplugs combine age estimates with cortisol measurements to assess spatial and temporal stress/stressor relationships. Here we show a relationship between baseline-corrected cortisol levels and corresponding whaling counts of fin, humpback, and blue whales in the Northern Hemisphere spanning the 20th century. We also model the impact of alternative demographic and environmental factors and determine that increased anomalies of sea surface temperature over a 46-year mean (1970–2016) were positively associated with cortisol levels. While industrial whaling can deplete populations by direct harvest, our data underscore a widespread stress response in baleen whales that is peripheral to whaling activities or associated with other anthropogenic change.

Twenty years of protection of historic values in Antarctica under the Madrid Protocol

ABSTRACT Even though the history of human activity in Antarctica is only 200 years old, there are a significant number of structures and artefacts left behind from these activities that make up the population of cultural heritage we find today. From nineteenth-century sealing sites to the wooden huts of explorers and scientists and to the ruins of industrial whaling stations the historic monuments and sites are important witnesses of past events. They are at risk from both natural degradation and from increased human presence in Antarctica. Recommendations relating to cultural heritage were formulated already at the first Antarctic Treaty Consultative Meeting in 1961, and in 1972, a list of historic sites and monuments (HSM) was compiled. The Madrid Protocol and its Annex V on Area Protection and Management represented a big step forward for cultural heritage management and further improvements have occurred during the 20 years since its entering into force. However, cultural heritage expertise has consistently been lacking in the Antarctic Treaty System and associated institutions to ensure adequate processes for HSM nominations and management. Current CEP initiatives indicate that this lack is acknowledged, and the gap may be filled in the future.

Species composition of First Nation whaling hunts in the Clayoquot Sound region of Vancouver Island as estimated through genetic analyses

Deepening our understanding of whale hunting practices is important from both cultural and biological perspectives. Many cultures practice whaling activities, including the Nuu-cha-nulth Nations of the Pacific Northwest. Nuu-cha-nulth cultural lifeways and laws include great care and respect for these animals that provide so much wealth to their communities. The disruption of this culture by colonial governments, combined with the decimation of whale populations through industrial whaling, led to the loss of traditional whaling activities and a gap between contemporary and historical knowledge and practices. From a scientific perspective, knowledge of current whale populations is compromised by lack of data with regards to abundance and distribution of these populations prior to colonial industrial whaling. Analysis of whale bones from First Nation whaling sites are valuable for addressing both these issues by identifying the species landed by communities in traditional hunts, and by providing a sample of the presence and distribution of whale species before colonial industrial whaling. Genetic analyses of 95 bones collected from 7 traditional whaling sites of Nuu-chah-nulth First Nations in the Pacific Northwest were conducted, as well as 11 bones from a colonial industrial whaling site in the area that operated from 1905 to 1918. Specifically, we sequenced a portion of the mitochondrial control region and cytochrome-b gene to identify what species were taken, and in what proportions. We found that 45.4% of the bones were from grey whales (Eschrictius robustus), 43.0% were from humpback whales (Megaptera novaeangliae), 8.1% were from North Pacific right whales (Eubalaena japonica), and the remaining 3.5% were from fin whales (Balaenoptera physalus). These results reveal catch compositions of historical hunts, and therefore help to inform our understanding of historic practices and preferences, and provide information on which species were present in these areas.

‘A Most Complete Whaling Museum’: Profiting from the Past on Nantucket Island

The Nantucket Historical Association found itself by 1930 suddenly transformed from a grass-roots collective to a modern nonprofit organization host to the ambitious new Nantucket Whaling Museum. The change owed largely to president William F. Macy, who promoted the museum as entrée into the nation's rising heritage tourism industry. And yet, by merit of its concern with a seafaring past inextricably bound with maritime labor and global economies, the museum unwittingly complicated the romantic portrayals of ships and their captains favored by local tourism boosters. Its core collection, for instance, a vast assemblage of industrial whaling tools donated by Progressive reformer Edward Sanderson, showcased the hard lives of workaday sailors. This article examines Macy's vision for Nantucket's past and how he sought to ensure that it would remain profitable, history notwithstanding. We discover how moments of institutional change can redistribute historical authority in ways that have considerable long-term impacts on museums and their publics.

Emptying the Oceans: A Summary of Industrial Whaling Catches in the 20th Century

Late 19th century technological advances for capturing whales, when combined with the expansion of processing capabilities in the early 20th century, created an industry that could catch and quickly render virtually any whale in any ocean. Here, using the current International Whaling Commission (IWC) database and other sources, we provide the fi rst accounting of the total global catch by industrial whaling operations in the 20th century. In sum, we estimate that nearly 2.9 million large whales were killed and processed during the period 1900–99. Of this total, 276,442 were killed in the North Atlantic, 563,696 in the North Pacifi c, and 2,053,956 in the Southern Hemisphere. The years 1925–39 in the Southern Hemisphere and 1946–75 in both hemispheres saw the highest totals of whales killed. For the entire 20th century, the largest catches were of fi n, Balaenoptera physalus, and sperm whales, Physeter macrocephalus, with 874,068 and 761,523 taken, respectively; these comprised more than half the total of all large whales taken. As noted in other publications, when one species began to decline, another was sought and hunted to take its place. In addition to reported catches, it is now known that the USSR conducted illegal whaling for more than 30 years. The true Soviet catch totals for the Southern Hemisphere were corrected some years ago, and a more recent assessment of the actual number of whales killed by Soviet factory fl eet ships in the North Pacifi c between 1948 and 1979 has provided us with more accurate numbers with which to calculate the overall global catch. The estimate for the total global catch by the USSR is 534,204 whales, of which 178,811 were not reported to the IWC. Introduction In the 1860’s, the Norwegian whaler and sealer Svend Foyn introduced the steam-powered whale catcher and the exploding harpoon gun to the whaling industry (Tonnessen and Johnsen, 1982). In the 1870’s, he improved upon shore-based factory processing to a level that came to be considered a standard for the industry (Tonnessen and Johnsen, 1982). By the time the 20th century began, the era of modern whaling—at least in the Northern Hemisphere—was well under way. Sixteen shore whaling stations had been established in Norway by 1883 (Risting, 1922; Dickinson and Sanger, 2005), and others were in operation in Newfoundland, Greenland, Russia, and Japan. In 1903, another Norwegian, Christen Christensen, introduced the fi rst factory ship, the wooden steamship Telegraf, into the waters off Spitsbergen (Tonnessen and Johnsen, 1982). Their primary targets were blue, Balaenoptera musculus; fi n, B. physalus; and humpback whales, Megaptera novaeangliae. However, industrial whaling south of the equator did not begin to resemble operations in the north until 5 years into the 20th century. Between 1900 and 1903, the only whales processed industrially were humpbacks caught via net and brought to a shore factory in Whangamumu Bay in New Zealand, a factory that had been established in 1890. The average catch was 8 whales per year during the 20-year operation of this factory (Lillie, 1915; Allison, 2012). The fi rst shore factory in the Southern Ocean was established in Grytviken (Cauldron Bay) on South Georgia Island by the Norwegian Carl Anton Larsen, from the Compania Argentina de Pesca, in late 1904 (Tonnessen and Johnsen, 1982). In 1903, one humpback whale was killed by modern methods by Adolf Andresen in the Straits of Magellan, but his processing station was not established until 1905 (Tonnessen and Johnsen, 1982). Thus, between 1900 and 1908, more whales were captured by industrial whaling methods in the Northern Hemisphere. By 1909, however, whaling south of the equator had surpassed that in the north. This trend continued until 1993, when the catch of whaling operations became comparable in the two hemispheres and were focused largely on minke whales, Balae“Some of the larger factory vessels with their capacity of over 2,500 barrels of oil per day capture more in two days than the original fl oating factories of 1904 were able to carry away with them in an entire season. One modern factory ship can take more whales in one season than the entire American whaling fl eet of 1846 which number over 700 vessels.” Lt (j.g.) Quentin R. Walsh, U.S.C.G., 1938

Validating the reliability of passive acoustic localisation: a novel method for encountering rare and remote Antarctic blue whales

Since its near extirpation during the period of industrial whaling in the early and mid 20th century, the once common Antarctic blue whale Balaenoptera musculus intermedia re mains extremely rare. While annual systematic surveys around Antarctica from 1978 to 2009 re corded only 216 visual encounters of this species, their loud and distinctive calls were detected frequently throughout the Southern Ocean. We describe and assess a new method for locating these whales by acoustically detecting their vocalisations, tracking the location of their calls, and finally locating the whales visually. This methodology was employed during an Antarctic research voyage from 140° E to 170° W, between January and March 2013. The loudest song unit (a 26 Hz tone) was detected at all 298 recording sites south of 52° S. Acoustically derived bearings from these whales enabled visual observers to eventually sight the whales, often hundreds of kilometres from initial acoustic detections. Received sound pressure levels of detections increased with decreasing range to several hotspots where both song and non-song calls were detected. Within hotspots, short- range acoustic localisation yielded 33 visual encounters of Antarctic blue whales (group size: 1 to 5 whales) over a 31 d period south of 60° S. These results demonstrate that acoustic tracking pro- vides the capacity to locate Antarctic blue whales widely dispersed over many hundreds of kilo- metres, as well as the capacity to acoustically track individual whales for days at a time irrespec- tive of most weather conditions. Thus, passive acoustic localisation is a reliable and efficient method to track Antarctic blue whales, and this technique should be considered for future studies of these iconic animals.

Whales as marine ecosystem engineers

Baleen and sperm whales, known collectively as the great whales, include the largest animals in the history of life on Earth. With high metabolic demands and large populations, whales probably had a strong influence on marine ecosystems before the advent of industrial whaling: as consumers of fish and invertebrates; as prey to other large‐bodied predators; as reservoirs of and vertical and horizontal vectors for nutrients; and as detrital sources of energy and habitat in the deep sea. The decline in great whale numbers, estimated to be at least 66% and perhaps as high as 90%, has likely altered the structure and function of the oceans, but recovery is possible and in many cases is already underway. Future changes in the structure and function of the world's oceans can be expected with the restoration of great whale populations.