Feature Creature

FEATURE IUCN RED LIST 2020 PHOTOGRAPHY DAVID ABEL

Scientific Name: Eubalaena glacialis

Synonym: Balaena glacialis Müller, 1776

Common Name: North Atlantic Right Whale

The taxonomy follows the view of the IWC Scientific Committee and the Society for Marine Mammalogy’s Committee on Taxonomy which now recognise Right Whales in the North Atlantic, North Pacific and Southern Hemisphere as three distinct species in the genus Eubalaena, namely E. glacialis (North Atlantic Right Whale), E. japonica (North Pacific Right Whale), and E. australis (Southern Right Whale) (IWC 2004), based mainly on the mtDNA phylogenetic findings of Rosenbaum et al. (2000).

The North Atlantic Right Whale was included in previous Red Lists together with the North Pacific Right Whale under the species name E. glacialis (Baillie and Groombridge 1996).

Rice (1998) classified Right Whales in the North Atlantic, North Pacific and Southern Hemisphere as the single species Balaena glacialis, in the genus Balaena along with B. mysticetus, the Bowhead Whale. While not all cetologists accept that the three Right Whale taxa qualify as full biological species, their clear geographical separation means that their treatment as separate taxa for conservation purposes is appropriate.

The estimated number of North Atlantic Right Whales alive at the end of 2018 was 409 individuals (Pettis et al. 2020), of which fewer than 250 were mature. The population was declining during 2011-2020 due to a combination of increased mortality rates (driven primarily by entanglement in fishing gear and vessel strikes) and reproductive rates below the average for previous years. Because the former eastern North Atlantic subpopulation of Right Whales, if it still exists, contains at most a few individuals, it can be assumed that the western North Atlantic subpopulation contains over 90% of North Atlantic Right Whales. The species therefore qualifies as Critically Endangered under criterion C2a(ii).

The Right Whale formerly was common on both sides of the North Atlantic. It appears to be effectively extirpated in the eastern North Atlantic but in the past probably ranged from a calving ground in the Golfo de Cintra (23°N) off Western Sahara, through the Azores, Bay of Biscay, western British Isles, and the Norwegian Sea to the North Cape (hence the Dutch, German and Scandinavian name Noordkaper/ Nordkaper) (Rice 1998). It may also have occurred in the Mediterranean Sea (Rodrigues et al. 2018). In the western North Atlantic the species migrates from calving grounds off Florida and Georgia along the eastern seaboard of North America, to summering grounds largely in the Gulf of Maine, south of Cape Cod, Bay of Fundy, Scotian Shelf, and Gulf of Saint Lawrence.

Today, North Atlantic Right Whales are regularly seen in the winter calving grounds off Florida and Georgia, and in spring/summer feeding grounds in Cape Cod Bay and south of Cape Cod, the Great South Channel off Massachusetts, the Gulf of Maine, the Scotian Shelf, the Bay of Fundy, and increasingly in the Gulf of Saint Lawrence (Hayes et al. 2019). There have been a few sightings off Cape Farewell (southern tip of Greenland) (Brown et al. 2007) and Iceland (Hamilton et al. 2007), and in the Gulf of Mexico (Ward-Geiger et al. 2011). Adult females appear to migrate to the southern calving grounds in winters in which they bear a calf while most males and other females do not migrate to the calving grounds, especially after summers with below-average prey abundance (Gowan et al. 2019).

There have been very few sightings in the northeast Atlantic in recent times. A possible Right Whale was sighted in the Bay of Biscay in 1977 (Aguilar 1981) and a cow-calf pair was sighted off Cape Vincent, Portugal in 1995 (Martin and Walker 1997). One Right Whale was apparently sighted off the island of Sardinia (Mediterranean Sea) in 1991, but a survey of the former Cintra Bay calving ground off Western Sahara failed to locate any Right Whales (Notarbartolo di Sciara et al. 1998). Individual Right Whales sighted off Norway in 1999, off the Azores in 2009 (Silva et al. 2012) and off France in 2019 (Pettis et al. 2020) have each been identified as animals from the western North Atlantic subpopulation (Jacobsen et al. 2004, Silva et al. 2012, Pettis et al. 2020). There have been unconfirmed reports from northwest Ireland and the Canary Islands.

The distribution map shows where the species is known to occur, based on confirmed records post-1900, and may occur, based on oceanography. The species has not been recorded for all the states within the hypothetical range as shown on the map.

Based mainly on photo-identification data, the North Atlantic Right Whale population was estimated to have been increasing at an average rate of 2.8% per year from 1990 to 2011, peaking at about 480 individuals in 2011. Abundance has been declining since 2011, to an estimated 409 individuals by the end of 2018. Reproduction has declined as reflected in both lower calf counts (average 10 calves per year observed during 2012-19, compared with 24 per year during 2004-11) and longer calving intervals. Associated with a lower estimated survival rate for females, the female proportion in the population is estimated to be only about 40%, despite a birth sex ratio close to 50:50. During 2017-19, only 12 calves were observed but 30 deaths were documented. (Pace et al. 2017, Pettis et al. 2020).

There has also been a change since 2011 in patterns of habitat use (IWC 2017). There has been a northward shift in summer distribution into the Gulf of Saint Lawrence, leaving fewer whales in the Bay of Fundy and Gulf of Maine (Stokstad 2017).

Calf counts have been conducted since 1980, and calf production has fluctuated. It was particularly low during 1998-2000 and again during 2012-2019, with no calves at all observed in 2018 (Pettis et al. 2020). Years of low calf production have been correlated with environmental conditions (Greene et al. 2003) and with poor body condition of adults (Rolland et al. 2016). Based on the pattern of occurrence in the calving grounds of females at different stages in the calving cycle, Browning et al. (2010) inferred that there is considerable cryptic perinatal mortality in addition to known calf deaths. For the period 1989-2003, those authors documented 191 surviving calves and 17 known calf deaths and estimated a further 28 cryptic calf deaths.

The demographics of North Atlantic Right Whales compare unfavourably with those of Southern Right Whales in terms of birth and death rates as well as indicators of health (Rolland et al. 2016, Corkeron et al. 2018). The occurrence of skin lesions of a kind not seen in Southern Right Whales was recorded in North Atlantic Right Whales during the period 1995 to 2002, and appeared to be correlated with the failure of females that would normally have been ready to have reproduced on schedule (Rolland et al. 2007). Body condition as measured by blubber thickness was poorer in the North Atlantic Right Whales than in Southern Right Whales (Miller et al. 2011).

Due to the paucity of records in recent times (see Geographic Range), and the fact that all photographed sightings have been identified as migrants from the west, it seems unlikely that there is a remnant northeast Atlantic breeding subpopulation. It is also unclear whether in the past the animals in the northeastern part of the range (off Iceland and Norway) belonged mainly to the western or eastern breeding subpopulations, or to what degree the two breeding subpopulations were separate.

The first documented records of Basque whaling in the Bay of Biscay are from the 11th century (Rey-Iglesia et al. 2018). At least dozens of Right Whales were killed each year in the Bay of Biscay until a marked decline was evident by 1650, and whaling declined during the 18th century. Basque whalers arrived in Iceland as early as 1412, and participated in the Right Whale fishery around the British Isles and Norway from the 14th to the 18th century, but probably many more whales were taken by Dutch, Danish, British, and Norwegian whalers. Quantitative estimates of catches are not available. Historical “right whale” catches as far north as Iceland and Norway appear to have been mainly Eubalaena glacialis, with Bowhead Whales being the main species only in the far north (Greenland and Svalbard) (Aguilar 1986). Smith et al. (2006) documented extensive whaling for Right Whales in the North Cape area (northern Norway) in the 17th century. Right Whale hunting in the northeastern Atlantic seems to have declined from the mid-17th century and all but disappeared by the mid-18th century, but there was a brief period of Right Whale catches by modern whalers operating from shore stations in the northwestern British Isles and off Iceland, with at least 120 Right Whales taken during 1881-1924 (Collett 1909, Brown 1986). The last recorded catch was a cowcalf pair off Madeira in 1967, accompanied by a third individual that escaped. There is some archaeological and historical evidence for a Right Whale wintering ground in the Mediterranean Sea in classical times, with a likely fishery near the Straits of Gibraltar (Rodrigues et al. 2018).

It is not clear when Basque whaling first spread to the western North Atlantic, but it had been established no later than 1530. It had long been thought that large numbers (tens of thousands) of Right Whales were taken off Labrador and Newfoundland by the Basques between 1530 and 1610 (Aguilar 1986, Reeves 2001) but recent genetic evidence suggests that many, if not most, of these were Bowheads (Rastogi et al. 2004, McLeod et al. 2008). Shore-based whaling along the US east coast began in the mid-17th century and continued at least sporadically over the next two and a half centuries (Reeves et al. 1999).

Historical catches, particularly in the northeastern Atlantic, are insufficiently documented to allow estimation of the prewhaling population size. Monsarrat et al. (2016) used historical catches in the North Pacific, which are better documented, to relate pre-whaling Right Whale summer abundance to habitat parameters, and then applied this relationship to the North Atlantic. This resulted in an estimated pre-whaling total abundance in the North Atlantic of 9,000-21,000, based on ecological carrying capacity. Much of this population is predicted to have summered in the Norwegian Sea and on the Grand Banks off Newfoundland.

Right Whales feed on calanoid copepods and other small invertebrates (smaller copepods, euphausids (krill), pteropods, and larval barnacles), generally by slowly skimming through patches of concentrated prey at or below the surface (Mayo and Marx 1990). The most common prey species is the copepod Calanus finmarchicus (Baumgartner et al. 2007).

Relative abundance of Right Whales has been positively correlated with copepod density off the northeastern United States (Pendleton et al. 2009), and also correlated with sea surface temperature, sediment type, and bathymetry (Good 2008). Baumgartner and Mate (2005) attached satellite-monitored radio tags to Right Whales in the Bay of Fundy in order to investigate their habitat use. They found that when the tagged animals left the Bay, they did not frequently visit the deep basins of the Gulf of Maine and Scotian Shelf, where abundance of C. finmarchicus was thought to be high. Instead, the whales visited areas characterized by low bottom water temperatures, high surface salinity, and high surface stratification.

Right Whales in the North Atlantic are no longer hunted, and the most serious current threat is death and injury from entanglements in fishing gear and ship strikes off the east coast of North America (Kraus et al. 2016). During 2012-2016, there were 30 confirmed humancaused deaths or serious injuries, including 26 entanglements and two ship strikes (Hayes et al. 2019). Because some human-caused deaths probably pass undetected, the reported events are minima. Entanglement events appear to be increasing in both frequency and severity (Knowlton et al. 2016). A further 30 deaths were recorded during 2017-19 of which 21 were in Canadian and nine in US waters (Pettis et al. 2020).

Photo-identification images revealed that most individual Right Whales (82.9%) bear evidence of being entangled at least once while over half (59.0%) of the individuals have been entangled more than once. The evidence suggests that Right Whales acquire new entanglement scars on a nearly annual basis, juvenile whales at a higher rate than adults (Knowlton et al. 2012). Based on observations during 19952008 of 50 free-living individuals observed to be carrying fishing gear, compared with 459 individuals never seen with gear during that period, Robbins et al. (2015) estimated a mortality rate of approximately 25% during the first year after which the individual was first seen with gear. Because some deaths may occur before the whale is seen with gear, this provides a minimum estimate of the mortality rate of entangled whales in addition to those that die immediately following entanglement. Even if not directly fatal, entanglement is detrimental to the whale’s energy balance leading to poorer body condition, lower reproduction and lower survival (Pettis et al. 2017, van der Hoop et al. 2017).

In the Bay of Fundy and on the Scotian Shelf (Canada), from 2004 to 2008, groundfish hook-and-line gear was found to pose the greatest risk to Right Whales during the summer, and lobster gear during the spring and autumn migration periods (Vanderlaan et al. 2011). However, of 12 Right Whale deaths recorded in the Gulf of Saint Lawrence in summer 2017, six were examined, and the cause of death was found to be entanglement in snow crab fishing gear in two cases and suspected to be blunt trauma consistent with vessel strike in four cases. In addition, five live whales were observed entangled including at least four in snow crab gear. Three of those whales were freed by human intervention or freed themselves, and the fate of the remaining two was unknown (Daoust et al. 2017, Taylor and Walker 2017).

Right Whales appear to be the most vulnerable large whales to ship strikes (Vanderlaan and Taggart 2007). Ship strikes were found to be the cause of death for 53% of the 40 Right Whales necropsied between 1970 and 2006 and could have been responsible for up to 10 individual North Atlantic Right Whale deaths per year (Vanderlaan et al. 2009). Confirmed Right Whale deaths due to ship strikes declined from 2.0 (2000-2006) to 0.4 per year (20122016) (Hayes et al. 2019). The decrease may have been due, in part, to spatial mitigation efforts (so-called Seasonal Management Areas, or SMAs) implemented in US waters in 2008 (van der Hoop et al. 2015).The SMAs were designed to correspond to Right Whale feeding, calving, and migration areas and it is estimated that this mitigation effort reduced mortality by 80-90% (Conn and Silber 2013). The risk of ship strike was reduced by an estimated 82% due to an “Area to Be Avoided” vessel-routing initiative implemented by the International Maritime Organization in the Roseway Basin Area on the Scotian Shelf (Vanderlaan and Taggart 2009). However, the shift in summer distribution of Right Whales may have increased their exposure to ship strikes in the most recent years. anthropogenic noise (especially ship noise) may negatively affect both reproduction by interfering with courtship vocalization and prey acquisition by interfering with communication and reducing feeding opportunities (Hatch et al. 2012).

Environmental neurotoxins produced as a result of harmful algal blooms have the potential to affect reproduction and development. Paralytic shellfish toxin and domoic acid that were detected in faecal samples indicate that Right Whales are exposed to environmental neurotoxins on an annual basis for up to six months of the year (Durbin et al. 2002, Doucette et al. 2012).

Climate change appears to have caused a northward shift in the summer distribution of North Atlantic Right Whales, likely due to effects on prey distribution, which exposes the Right Whales to shipping and entanglement risks over a greater area (Meyer-Gutbrod et al. 2018).

This North Atlantic Right Whale is no longer hunted. It was once the target of major commercial whaling.

Right Whales have been protected from hunting by the International Convention for the Regulation of Whaling since it came into force in 1948, and by its predecessor in the 1930s. The North Atlantic Right Whale is listed as Endangered under both the US Endangered Species Act and the Canadian Species At Risk Act and it is listed in Appendix I of both the Convention on International Trade in Endangered Species and the Convention on the Conservation of Migratory Species of Wild Animals.

Efforts are underway in both the US and Canada aimed at limiting North Atlantic Right Whale deaths and injuries due to ship strikes and entanglements. In both countries, recovery plans have been implemented. In US waters, mandatory time-area speed restrictions in the form of Seasonal Management Areas were implemented in 2008 in an effort to reduce the frequency and severity of ship strikes. A Mandatory Ship Reporting Scheme has been in place since 1999 in two areas of the Right Whale calving and summering grounds to warn vessels of whales’ presence. Regulations specify minimum approach distances for whale-watching and other vessels. Regulations are in place in the US involving restrictions on certain types of fishing gear in areas where,and times when, Right Whales are common. Pace et al. (2015) found that measures adopted prior to 2009 to reduce entanglements had not been effective. New measures adopted since 2009 have yet to be evaluated (Hayes et al. 2019).

Canada has introduced measures to limit ship speeds and close areas to snow crab, lobster and other non-tended fixed-gear fishing in areas where the Right Whales are common and in other areas following sightings of Right Whales (Fisheries and Oceans Canada, 2019).

CITATION Cooke, J.G. 2020. Eubalaena glacialis (errata version published in 2020). The IUCN Red List of Threatened Species 2020. Accessed on 15 February 2022. www.iucnredlist.org