Killer whale

Updated: March 2019

The killer whale is the largest species in the family Delphinidae. The killer whale has a massive body and a poorly defined beak compared to other dolphin species. A highly distinctive feature of the killer whale is its black and white colouring pattern. The body is largely black dorsally and white ventrally. Behind the eyes are noticeable oval white patches, referred to as eye patches. Behind the rear base of the dorsal fin is a grey patch, the so-called saddle patch. Pectoral fins (also called flippers) are oval in shape and the dorsal fin has a triangular shape, which may differ between individuals.

Killer whale sightings during North Atlantic Sightings Surveys from 1987-2015. Not all areas were surveyed each year.
killerwhale_assessment_table

ABUNDANCE

Estimated to be around 15,000 for the whole North Atlantic from the North Atlantic Sightings Survey (NASS) in 2001.

DISTRIBUTION

Found worldwide, and widespread throughout the North Atlantic. Likely more abundant in the Northeast Atlantic versus the Northwest Atlantic. Low numbers observed in West Greenland.

RELATION TO HUMANS

Killer whales are popular animals for whale watching activities. Hunted opportunistically in Greenland.

CONSERVATION AND MANAGEMENT

NAMMCO provides advice to the member countries on conservation status, and hunting in Greenland.

The species is listed as ‘Data Deficient’ on the IUCN Red List for both the European and global stock in the most recent assessments (2007 and 2017, respectively).

© Norwegian Orca Survey

© Fernando Ugarte

Scientific name: Orcinus orca

Faroese: Bóghvítuhvalir / Mastrarhvalir
Greenlandic: Aarluk
Icelandic:Háhyrningur
Norwegian:
Spekkhogger, staurhval

Danish: Spækhugger
English: Killer whale, Orca

Lifespan

Females average about 50 years (but oldest known female in the wild was estimated to be 105 years old)

Males average about 30 years (with maximum of about 60 years)

Average Size

Females: 5-7 m, 3-4 metric tonnes (maximum recorded 8.5 m and 7.5 tonnes)

Males: 6-8 m, 5-6 metric tonnes (maximum recorded 10 m and 10 tonnes)

The size of killer whales also varies greatly regionally

Migration and Movements

Killer whale movements seem mainly to be associated with the movement of their prey. Some long distance movements have been documented, but they do not have a migration route in the North Atlantic per se

Feeding

As a species, they are considered a generalist predator with a diverse diet that includes bony fish, sharks, pinnipeds, other cetaceans, seabirds, reptiles and squids. However, some groups of killer whales can become specialists for certain prey, with adaptive behaviours for that prey

© Fernando Ugarte

At Sea

At sea, the species can easily be identified due to its robust body, its tall standing dorsal fin and unique black and white coloration. Even though the blow reaches easily 3 meters high, the black erect fin is the first discernable clue at sea. Killer whales are commonly found in groups.

Physical appearance

Sexual dimorphism is highly discernible in killer whales, both in terms of body length and size of the dorsal fin, and the size of these animals varies greatly regionally. When mature, male killer whales average 6-8 metres in length and 5-6 metric tonnes in weight, but they can reach up to 10 metres and weigh a maximum of 10 tonnes. Females average 5-7 metres in length and 3-5 metric tonnes in weight, and can reach a length of 8.5 meters and a weight of 7.5 tonnes. Flukes, pectoral and dorsal fins are much more developed in males than females. A male’s dorsal fin can easily be twice the height of a female’s.

The killer whale is the largest species in the family Delphinidae. The killer whale has a massive body and a poorly defined beak compared to other dolphin species. A highly distinctive feature of the killer whale is its black and white colouring pattern. The body is largely black dorsally and white ventrally. Behind the eyes are noticeable oval white patches, referred to as eye patches. Behind the rear base of the dorsal fin is a grey patch, the so-called saddle patch. Pectoral fins (also called flippers) are oval in shape and the dorsal fin has a triangular shape, which may differ between individuals.

Colouring pattern and morphology can greatly vary among regions and/or populations.

Killer whale types

Although killer whales are currently considered a single species, evidence has suggested a more complex situation with potential separate species status. Indeed, differences in colour pattern, diet, morphological traits, behaviour, acoustics and genetics have led to the description of a mosaic of types of killer whales throughout the world (Pitman and Ensor, 2003; Morin et al., 2010; Foote et al., 2016). In the North Atlantic, the occurrence of two disparate types was suggested. The generalist type 1 could be feeding on diverse prey types, with the diet of certain groups including both fish and mammalian prey, whereas the specialist type 2 would be highly specialized on baleen whales (Foote et al., 2009).

Life history and ecology

Behaviour

Killer whales occur in groups, both in coastal and pelagic waters. They are one of the most popular marine mammals among whale watchers due to commonly displayed aerial behaviours including breaching (when a large part of the body is propulsed out of the water and lands on the sea surface in a huge splash), spy-hopping (when a whale rises its head vertically out of the water) and lob-tailing (when slapping the fluke on the sea surface). The meaning for these behaviours remains poorly understood but could have social implications.

Killer whales usually adopt a cruising speed of 10 to 13 km per hour, and they are able to maintain brief swimming speeds of 45 km per hour. Typically, killer whales remain less than a minute underwater but can extend their diving times to nearly 15 minutes. Killer whales tend to occur in the upper 20 m of the water column but can perform deep dives to 100-250 metres when foraging.

killer whale breaching
Breaching killer whale © Eve Jourdain / Norwegian Orca Survey
spyhopping killer whale
Spyhopping killer whale © Eve Jourdain / Norwegian Orca Survey
lobtailing killer whale
Lobtailing killer whale © Eve Jourdain / Norwegian Orca Survey

Social organization

Pod of killer whales © Eve Jourdain / Norwegian Orca Survey

Killer whales are highly social and group-living animals. But importantly, social organisation and behaviours greatly vary with prey types hunted and ecology. The main stable unit is a matriline, in which the oldest female (referred to as the matriarch) is the leader, accompanied by her daughters and sons and their offspring. A matriline can be particularly stable in composition and can gather up to 3-4 generations of related individuals. Dispersal from the natal group can occur but greatly depends, and so does the group size, on the specific ecology and dietary habits of the group. Distinct but related matrilines can temporarily associate, leading to groups of several tens, or even a hundred individuals (Bigg et al., 1990).

Sound and communication

Killer whales’ primary sense is the auditory system. Three main types of sound including echolocation clicks, whistles and calls are used. As a toothed whale species, killer whales produce low frequency, directional, broadband echolocation clicks and listen to their echo in order to get a ‘picture’ of their surroundings but also to navigate and locate prey.

Loud calls are typically exchanged for long-range communication and movement coordination. These calls can be effective at ranges that exceed 10 to 20 km. Whistles appear to be used for close-range communication and behavioural interactions between individuals. The repertoire of calls, or dialect, is specific to each group (Ford, 1991).

 

Reproduction

Female killer whales typically give birth to their first viable offspring at 12-14 years of age after a gestation of 17-18 months. Calves are nursed for 1 to 2 years, gradually including solid food into their milk diet. Females produce in average 4 to 5 calves throughout their reproductive lifespan. When they reach approximately 45 years of age, females become post-reproductive but may live up to 80 years.

Males become sexually mature at about 15 years of age, after which the dorsal fin grows substantially. Males appear to have a shorter life expectancy, which is in average 30 years.

Importantly, due to late sexual maturity, low calf production per female and a prolonged post-reproductive phase, the potential for population growth and recovery remains low.

Killer whale with calf © Fernando Ugarte

Diet and feeding behaviour

The killer whale, as a species, is considered a generalist predator with a diverse diet that includes bony fish, sharks, pinnipeds, other cetaceans, seabirds, reptiles and squids (Ford, 2009). However, local populations may display strong prey preferences for which they develop specific feeding strategies and adapt behaviours. A well known example is about the two types of killer whales that occur in the coastal waters of BC, Canada and WA, USA. Whilst the resident type of killer whales is exclusively fish-eating, preferentially feeding on salmon species, the transient killer whales entirely specialise on marine mammal prey (Baird and Dill, 1995; Ford and Ellis, 1998).

Northwestern Atlantic

In the North Atlantic Ocean, killer whales also include a wide range of prey species. In Atlantic Canada, prey taken includes baleen whales such as humpback whales (Megaptera novaenagliae) and minke whales (Balaenoptera acutorostrata); toothed cetaceans such as beluga whales (Delphinapterus leucas) and white-beaked dolphins (Lagenorhynchus albirostris); pinnipeds; seabirds; herring and tuna (Sergeant and Fisher, 1957; Whitehead and Glass, 1985; Lawson et al., 2007). Whether these killer whales are generalist feeders or display group-specific prey specialisations remains unknown.

In contrast with killer whales from Greenland and Newfoundland-Labrador, where evidence suggested both fish and marine mammal prey, only marine mammals have been reported as being part of the Canadian Arctic killer whale diet so far. Their diet regularly includes harp seal (Pagophilus groenlandicus), ringed seal (Pusa hispida), bearded seal (Erignathus barbatus), harbour seal (Phoca vitulina), hooded seal (Cystophora cristata), narwhal (Monodon monoceros), beluga and bowhead whale (Balaena mysticetus) (Reeves and Mitchell, 1988; Ferguson et al., 2012 a and b; Higdon et al., 2012). Nevertheless, predation on fish cannot be ruled out.

Based on stomach contents, west Greenlandic killer whales appear to feed on fish prey (Heide-Jørgensen, 1988), including lumpsucker fish (Cyclopterus lumpus; Laidre et al., 2006) and Greenland halibut (Reinhardtius hippoglossoides), but also cephalopods (see Jensen and Christensen, 2003) while killer whales off Tasiilaq (east Greenland) appear to feed mainly (and potentially exclusively) on marine mammals (Ugarte et al., 2013).

Northeastern Atlantic

Killer whales off Iceland and Norway specialise and primarily feed on the Atlantic herring (Clupea harengus), being mainly associated with the Icelandic Summer Spawning (ISS) and Norwegian Spring Spawning (NSS) stocks, respectively (Sigurjónsson et al., 1988; Similä et al., 1996; Simon et al., 2007; Foote et al., 2010; Samarra et al., 2012). Both sub-populations adopt similar feeding strategies in which the herring is cooperatively herded as a tight school below the sea surface, before debilitating the prey with underwater tail-slaps and consuming herring one by one (Simila and Ugarte, 1993; Similä, 1997; Simon et al., 2005). However, confirmed observations of killer whales preying on seabirds, grey seals (Halichoerus grypus) and minke whales have also been reported in Icelandic waters (Vikingsson, 2004) and a few individuals are known to seasonally return to Scotland for predation on seals (Foote et al., 2010; Samarra and Foote, 2015).

Other prey items documented for Norwegian killer whales include cod, squid, bottlenose whales (Hyperoodon ampullatus), mackerel, Atlantic salmon (Salmo salar), pinnipeds and seabirds (Jonsgård, 1968; Vester and Hammerschmidt, 2013; Vongraen and Bisther, 2014; Nøttestad et al., 2014). Around Scotland-UK, killer whales mainly prey on grey seals, harbour seals and mackerel (Weir, 2002; Luque et al., 2006; Bolt et al., 2009; Deecke et al., 2011).

In several locations, killer whales have been observed associating with fishing vessels and scavenging around nets, as for the mackerel fisheries between Scotland and Norway and for the herring fisheries off Northern Norway. Yet, much remains to be discovered about potential prey specialisations and local feeding behaviours in the North Atlantic.

killer whales herring fishing
Killer whales feeding near herring fishing boat © Eve Jourdain / Norwegian Orca Survey

Distribution and habitat

Killer whales are cosmopolitan, ranging in all the world’s oceans, and they are increasingly abundant in high latitude productive waters (Leatherwood and Dahlheim, 1978; Forney and Wade, 2006). Killer whales inhabit both coastal and offshore waters and their movement appears to be primarily associated with the availability and abundance of prey (e.g. Sigurjónsson and Leatherwood, 1988; Similä et al., 1996).

Distribution in the North Atlantic

Killer whales widely range from the east coast of Canada to Norwegian waters. More specifically, they occur all along the eastern Canadian coast, from the Bay of Fundy and north to the Arctic (Sergeant and Fisher, 1957; Whitehead and Glass, 1985; Lien et al., 1988; Reeves and Mitchell, 1988), although they are more common in the Newfoundland and Labrador regions. They are only seldom seen in the Gulf of St Lawrence, coastal Nova Scotia, the Bay of Fundy and north-eastern USA (Lawson et al., 2007). In the Eastern Canadian Arctic, killer whales occur seasonally during summer.

Canada, Greenland and Iceland

Historically, killer whales were known to occur in Canadian Arctic regions such as Davis Strait and Baffin Bay (Reeves and Mitchell, 1988) but killer whale sightings have recently increased in Hudson Bay, presumably following a longer ice-free season that provides a greater open water habitat (Higdon 2007; Higdon and Ferguson, 2009). Killer whales are known to occur all around Greenland, yet appear to be more common off western Greenland (Heide-Jørgensen, 1988). A recent increase in killer whale sightings was observed off Tasiilaq, east Greenland (Ugarte et al., 2013). Off Iceland, killer whales occur all along the coast all year round with a peak of observation in the summer herring grounds (Gunnlaugsson et al., 1988; Sigurjónsson et al., 1988).

British waters and the Norwegian coast

Off the coast of the UK, the Northern Isles and north-east of Scotland, killer whales are also regularly sighted (Bolt et al., 2009; Foote et al., 2010; Beck et al., 2012). A subset of killer whales ranging off the east coast of Iceland is known to seasonally travel to Scotland (Foote et al., 2010; Samarra and Foote, 2015). An assemblage of killer whales occurring off the west coast of Scotland, Ireland and Wales was suggested as a population isolated from neighbouring killer whales (Beck et al., 2014). Killer whales occur all along the Norwegian coast, with the main concentrations off Northern Norway and Finnmark.

Migration

Even though long-distance movement has been documented (over 5000 km travelled in a month; Matthews et al., 2011), no evidence for migration in the North Atlantic has been brought forth so far.

Killer whale sightings during North Atlantic Sightings Surveys from 1987-2015. Not all areas were surveyed each year.

North Atlantic Stocks

Stock definition

Whilst effective conservation of marine predators requires the delineation of population units, or “stocks,” baseline information about abundance, distribution and movements between different locations is required for management purposes. In the North Atlantic, the preliminary investigations of killer whale abundance and distribution were largely based on whaling records, incidental observations or stranding data. But recent efforts dedicated to describing populations have greatly improved our understanding of the species. As such, extensive studies conducted off Iceland, Norway and UK-Scotland, resulting in over 1,000 individual killer whales identified across the north-east Atlantic and a comparison of identification catalogues revealed site fidelity at several locations with distinct populations largely associated with particular prey resources (Foote et al., 2010).

Populations and management units

Due to high site and prey resources fidelity (shown by photo-identification studies e.g. Similä et al., 1996; Foote et al., 2010), the influence of diet, movement patterns and contact between groups can be used as an indicator of population structure and management units. In the Northeast Atlantic, three distinct killer whale populations have been suggested based on their association with their major prey source:

  1. the Atlantic herring population (including killer whales from the North Sea, Iceland and Norway),
  2. the Northeast Atlantic mackerel population, and
  3. the eastern stock of the Atlantic bluefin tuna (Thunnus thynnus) population (Foote et al., 2011).

Killer whales around Iceland © Fernando Ugarte

Iceland and Norway

No movement between killer whale groups following the Icelandic Summer Spawning (ISS) and Norwegian Spring Spawning (NSS) herring stocks was detected by photo-identification data (Foote et al., 2010). However, genetics and acoustics has suggested former or on-going contact between the Icelandic and Norwegian sub-populations (Strager, 1995; Simon et al., 2007; Foote et al., 2009; Samarra et al., 2010).

British waters

Killer whales ranging in British waters appear to belong to distinct populations. Large numbers of killer whales are known to occur off the east coast of the UK, and are associated with the Northeast Atlantic mackerel stock during autumn (Luque et al., 2006; Foote et al., 2010). Off the Northern Isles and the northeast of Scotland, about 50 individuals are site-faithful returning every spring-summer to feed on pinnipeds (Bolt et al., 2009; Foote et al., 2010; Beck et al., 2012). A subset of these killer whales belong to the herring feeding sub-population off the east coast of Iceland, from where they seasonally migrate (Foote et al., 2010; Beck et al., 2012; Samarra and Foote, 2015). Another assemblage of killer whales occurring off the west coast of Scotland, Ireland and Wales was suggested as a population isolated from neighbouring killer whales (Beck et al., 2014).

Northwestern Atlantic

In the northwest Atlantic, photographic data and simultaneous seasonal sightings in several regions such as Greenland and Newfoundland (Heide-Jørgensen, 1988; Lien et al., 1988) suggest a possibility of several populations ranging in the western Atlantic, or one large and widespread population.

The main management issue lies in the fact that real baseline data on killer whale abundance, distribution and population structure in this region is still missing (Higdon, 2007). For effective management of the species, further data are needed and biopsy sampling for genetic analyses could assist in assessing management units and possible movement between the Canadian Arctic/Atlantic and Greenland (Higdon, 2007).

Total abundance in the North Atlantic

Killer whales are largely distributed throughout the North Atlantic but densities greatly vary among locations, presumably in relation with variations in resource distribution and possibly due to former removals that may have negatively impacted population size. Numerous abundance estimates were produced at different scales for Northeastern Atlantic waters. As such, Christensen (1988) estimated that about 483-1,507 killer whales could be using Norwegian coastal waters based on questionnaire-based surveys that reflected the period 1982-1987. Later on, line transect surveys conducted in the Norwegian Sea resulted in an estimate of 3,100 animals (Øien, 1990). More recently, Kuningas and colleagues (2014) investigated demographics of killer whales associated with the NSS stock of herring and estimated this sub-population to count about 1,000 individuals. On a larger scale, a North Atlantic Sightings Survey (NASS, 2001) produced an estimated number of 15,014 killer whales (95% CI = 6,637-33,964) between the Faroes and Atlantic Canada.

Following a literature review, killer whales were categorised as abundant in Norwegian waters, common off Iceland and the Faroe Islands but rarely observed off the UK (Forney and Wade, 2006). No abundance estimate currently exists for the Northwest Atlantic but based on available data, it was suggested that the Northwest Atlantic population is not as large as the one in the Northeastern Atlantic (Lawson and Stevens, 2014).

Abundance in different areas

Atlantic and Arctic Canada

Due to a relatively large study area combined to a little observer coverage and a systematic effort in monitoring killer whale occurrence only recently established, there is currently no reliable estimate of killer whale abundance for Atlantic Canada. However, recent efforts have enabled photo-identification of a minimum of 67 individuals in the Newfoundland and Labrador regions (Lawson et al., 2013). In Canadian Arctic waters, a minimum of 53 individuals was identified, with no re-sighting detected between Arctic and Newfoundland-Labrador killer whales (Young et al., 2011). Little is known about killer whales ranging in these two distinct regions and these numbers are undoubtedly under-estimates of killer whale abundance.

Greenland

Killer whales do not appear to be abundant in Greenlandic waters, as suggested by very few sightings on yearly fishery surveys (Ugarte et al., 2013). No killer whale abundance estimate currently exists for this region and preliminary results of photo-identification attempts resulted in only 15 individuals identified (source catalogue available at www.descna.com).

Iceland

Preliminary abundance estimates range from 4,000 to 6,847 killer whales, but these numbers may include killer whales from several populations over large areas (Gunnlaugsson and Sigurjónsson, 1990). A recent study identified a minimum of 314 individuals regularly using the waters off the southern and west coasts of Iceland (Tavares et al., 2016).

UK-Scotland

Killer whales are encountered year-round in UK waters but no abundance estimate exists for this specific location (Reid et al., 2003). Based on evidence that some killer whales may be widely travelling in this part of the Northeast Atlantic, it is likely that available abundance estimates include killer whales from UK waters as well (Samarra and Foote, 2015).

Norway

Various abundance estimates has been provided for killer whales off the Norwegian coast. Christensen (1988) estimated that at least 1,500 killer whales could be using Norwegian coastal waters when the herring over-winters close to shore. The North Atlantic Sighting Survey (NASS) later provided an estimate of 7,000 killer whales ranging in Norwegian waters (Øien, 1993), although these whales likely belong to several populations.

Long-term photo-identification studies enabled to catalogue a minimum of 686 individual killer whales occurring in the winter herring ground in 1986-2005 and 2007-2013 and a total abundance estimate of about 1,000 individuals was suggested (Similä et al., 1996; Kuningas et al., 2014). As the identification study continues, a minimum (and temporary) number of 862 individual killer whales appear to be regularly using coastal waters of Northern Norway (Jourdain and Karoliussen, 2016).

Changes in trends

Western North Atlantic

While killer whales were historically present in Davis Strait and Baffin Bay in Arctic Canada, they recently extended their range to Hudson Bay, a region that has become regularly visited. The bay typically undergoes a yearly cycle with sea-ice formation from late October and breakup during the summer months. Sea ice persisting throughout the year in Hudson Strait may have prevented killer whales from using the bay, despite a great diversity of marine mammal prey available.

A marked climate shift has resulted in a drastic decrease in both extent and duration of sea ice in Hudson Bay. Since the 1950s, killer whale sightings have dramatically increased here. Visits have been possibly yearly from the 1980s, presumably in relation to a longer ice-free season that provides a suitable open water habitat (Gagnon and Gough 2005; Higdon, 2007; Higdon and Ferguson, 2009). As killer whales are known to largely prey on cetaceans in this region, predation on belugas, narwhals and bowhead whales may increase significantly with potential negative impacts on these prey populations (Ferguson et al., 2010). Concerns for the recovery of the Eastern Canada-Western Greenland bowhead whales have been raised (Reinhart et al., 2013).

Eastern North Atlantic

During the last decade, killer whales have also become more common off Tasiilaq, East Greenland. However, it is unknown if this shift in distribution and/or abundance is related to a shift of prey, increasing water temperatures, decreasing ice cover or a combination of these factors (Ugarte et al., 2013).

Off Norway, shifts in the herring wintering distribution since 2007 have resulted in a possible increase in killer whale abundance during these months. Indeed, the wintering ground for the NSS stock of herring, formerly located in inner fjords of the Lofoten region, shifted to more open waters mainly located between 69°N and 73° (Huse et al., 2010) over the last decade. The displacement of the wintering herring ground to a more open area may have brought this abundant prey resource within the reach of additional killer whale groups, as suggested by new adult individuals identified since 2011 that were not present in the former catalogues. However, such increase in killer whale abundance on the herring wintering ground is likely to reflect shifts in killer whale distribution from other locations in response to a dynamic prey resource rather than an increase in abundance of killer whales per se.

Western Atlantic

The Northwest Atlantic population of killer whales is managed as one unit and is listed as a species of Special Concern under COSEWIC (COSEWIC, 2008). Hunting activity in Greenland was listed as a threat to this population.

Eastern Atlantic

Killer whales in the North-eastern Atlantic appear to be associated to specific prey resources and three distinct populations were suggested (Foote et al., 2009). However, due to a small sample size relative to high abundance estimates and poorly understood movement patterns across the Atlantic, delineation of management units yet remains to be improved with further baseline information required at local levels. For instance, a small community of 10 killer whales found off Western Scotland, Ireland and Wales appears to be isolated from other local killer whale groups, with which no association has been observed. Because no new individuals have been born in nearly 20 years of monitoring, this isolated group is in decline and was recommended to be managed as a separate conservation unit (Beck et al., 2014).

Management

NAMMCO provides management advice to the Faroe Islands, Greenland, Iceland and Norway and on the conservation status of killer whales. Killer whales in Eastern Canada are managed by the Department of Fisheries and Oceans, and the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) has reviewed the species, listing the killer whales in Eastern Canada as “threatened.”

Direct catches

From 1938-1981, killer whales were caught over a wide area of the North Atlantic and reported catches included 1,961 animals in Norwegian coastal and offshore waters, Barents Sea, Jan Mayen, Bear Island and Svalbard, 140 in the North Sea, 153 in Iceland and 181 off Eastern and Southern Greenland. Although the target species of whaling operations was the minke whale, other cetaceans such as killer whale were caught when encountered. Killer whale catches were of minor commercial value to the whalers and the meat was only used as food for pets and fur farms. From the late 1960s, killer whales were also caught in response to complaints from fishermen that killer whales were interfering with the recovery of the depleted herring stock (Øien, 1988).

Greenland

Killer whales have always been hunted in Greenland, mainly opportunistically. A bounty was introduced in 1960 and maintained until 1975. Only 10 catches were reported, but this is likely an underestimate, not accounting for whales struck and lost (Heide-Jørgensen, 1988). As of today, killer whales are legally hunted off Greenland, and reporting catches has been obligatory since 1996. A minimum of 130 killer whales has been taken since the 1950s (gap in data for period 1987-1995). Since 2008, a sharp increase in killer whale catches was recorded off Tasiilaq, East Greenland, where what was previously opportunistic and rare game has become a regular hunting activity. No regulations for killer whale hunting currently exist in Greenland, and conservation related questions have been raised (Ugarte et al., 2013).

Norway

Killer whale hunting in Norway dates as far back as 1920, but catches were recorded only from 1938 (Bloch and Allison, 2005). After licensing of small-type whaling was introduced in Norway in 1938, all killer whale catches were required to be reported, and the logbook counted 2,435 killer whales caught from 1938 to 1981 (Øien, 1988). In 1982, killer whales became protected by the Norwegian law.

Canada

In Canada, killer whales were hunted either as a target or competitor species until 1972, when commercial whaling was banned (Lawson et al., 2007). Currently, only whaling for Aboriginal subsistence remains permitted, based on the importance of whales as a food source and for the culture of Aboriginal communities (Higdon, 2007). However, lethal interactions with fisheries may still occur, as suggested by a photograph recently taken of a killer whale calf displaying a bullet wound on its head (Lawson et al., 2007).

Reported catches in Greenland

CountryYearAreaCatch Total
Greenland2018EastAvail. 2020
Greenland2018WestAvail. 2020
Greenland2018TotalAvail. 2020
Greenland2017East11
Greenland2017West6
Greenland2017Total17
Greenland2016East2
Greenland2016West12
Greenland2016Total14
Greenland2015East7
Greenland2015West16
Greenland2015Total23
Greenland2014East6
Greenland2014West10
Greenland2014Total16
Greenland2013East11
Greenland2013West27
Greenland2013Total38
Greenland2012East12
Greenland2012West32
Greenland2012Total44
Greenland2011East5
Greenland2011West34
Greenland2011Total39
Greenland2010East1
Greenland2010West14
Greenland2010Total15
Greenland2009East5
Greenland2009West9
Greenland2009Total14
Greenland2008EastN/A
Greenland2008West26
Greenland2008Total26
Greenland2007EastN/A
Greenland2007West3
Greenland2007Total3
Greenland2006East0
Greenland2006WestN/A
Greenland2006Total0
Greenland2005East0
Greenland2005West2
Greenland2005Total2
Greenland2004East2
Greenland2004West12
Greenland2004Total14
Greenland2003East2
Greenland2003West3
Greenland2003Total5
Greenland2002EastN/A
Greenland2002West21
Greenland2002Total21
Greenland2001EastN/A
Greenland2001West2
Greenland2001Total2
Greenland2000EastN/A
Greenland2000West1
Greenland2000Total1
Greenland1999EastN/A
Greenland1999West6
Greenland1999Total6
Greenland1998EastN/A
Greenland1998West1
Greenland1998Total1
Greenland1997EastN/A
Greenland1997West4
Greenland1997Total4
Greenland1996EastN/A
Greenland1996West3
Greenland1996Total3
Greenland1992-1995Total*No reported catches

This database of reported catches is searchable, meaning you can filter the information by for instance country, species or area. It is also possible to sort it by the different columns, in ascending or descending order, by clicking the column you want to sort by and the associated arrows for the order. By default, 30 entries are shown, but this can be changed in the drop-down menu, where you can decide to show up to 100 entries per page.

Carry-over from previous years are included in the quota numbers, where applicable.

You can find the full catch database with all species here.

You can find a complete file with all comments and explanations here, under Overview Documents.

For any questions regarding the catch database, please contact the Secretariat at nammco-sec@nammco.no.

Live-capture fisheries

59 (1976-1988; Sigurjónsson and Leatherwood, 1988) and 64 (1960-1983; Bloch and Lockyer, 1988) killer whales were live-captured the 1960s to 1980s in Icelandic and Faroese waters, respectively. The purpose of these captures was sale and export to oceanariums.

Other Human Impacts

The main threats to killer whales include pollution, prey depletion and to a lesser extent ship-strikes, oil spills, boat traffic (and associated acoustic disturbance) and lethal interactions with fisheries (e.g. Poncelet et al., 2010).

Pollution

Anthropogenic contaminants such as pesticides, industrial organics, and heavy metals have become widely distributed throughout natural habitats. Being highly toxic and persistent, they accumulate up food webs, contaminating organisms and causing deleterious effects. Because killer whales are long-lived apex predators, they accumulate high concentrations of these contaminants (Ross et al., 2000; Wolkers et al., 2007; Jepson et al., 2016). Some documented negative effects of contaminants include reproductive and immune system impairment, disruption of the hormone system and increased prevalence of cancer. Whilst elevated contaminant loads have been measured in declining cetacean populations in Europe, contaminant exposure could have significant effects at the population level through lower recruitment induced by reproductive toxicity (Jepson et al., 2016).

Prey depletion/overfishing

Due to overfishing and degradation of habitats, killer whales may have to deal with low prey concentrations at particular locations. Availability of prey species has been shown to have effects on both survival and reproduction of killer whales (Ward et al., 2009; Ford et al., 2010). Such information is of particular concern for killer whale groups or populations showing high levels of prey specialisations due to high dependence on certain prey resources. Consequently, by impacting recruitment and survival, prey availability can influence population growth.

Oil spills

Contact with oil spills may have lethal effects on killer whales through inhalation of toxic vapours or ingestion of oil. Such major environmental perturbation could greatly lead entire groups and/or populations to a sharp decline or even extinction (Matkin et al., 2008).

By-catch and entanglements

Although not very common, incidental mortality caused by fishing gear has been reported (Lawson et al., 2007). Indeed, killer whales may deliberately associate with fishing boats, as documented between Scotland and Norway with the mackerel and herring fisheries (Luque et al., 2006). Scavenging around fishing nets may provide killer whales with an important proportion of their daily energy requirements and appears to have become an emerging feeding strategy in several locations. Off Northern Norway, while killer whales commonly associate with the commercial herring trawlers during the winter months, several cases of killer whales trapped in purse seine nets has been recorded.

© Norwegian Orca Survey

Greenland

The Greenland Institute of Natural Resources (GINR) occasionally conducts interview-related surveys among hunters and collect biological samples on killer whale catches. Even though data are opportunistically collected, preliminary results showed that killer whale hunting that was historically a rare activity, has become a more important game species in the region of Tasiilaq.

A few samples collected from Greenlandic killer whales were included in a global study that aimed at identifying killer whale populations across the North Atlantic (Foote et al., 2013). These killer whales appear to be related to the herring and mackerel feeding killer whales found in Iceland, Norway and in the North Sea. Studies to evaluate contamination levels of the killer whales caught off Tasiilaq and potential effects for humans that consume the meat are underway at Aarhus University, Denmark.

Iceland

The Marine and Freshwater Research Institute (MFRI) initiated the first investigations of killer whales occurring in the herring overwintering grounds of East Iceland. Currently, the Institute, along with the Icelandic Orca Project and the Sea Mammal Research Unit (Saint Andrews, Scotland) are the main actors monitoring population abundance and structure, acoustics, behaviours, feeding ecology and levels of contamination. The Icelandic killer whale catalogue containing over 400 killer whale individuals identified between 2006 and 2015 was published on the MFRI web site in 2017.

A long-term project on killer whales was started in 2008, and the current focus of the project is to investigate dietary specialisation. The MFRI and the Icelandic Orca Project conducted a field season in Vestmannaeyjar during summer 2018, focusing on collecting information on prey targeted and dietary preferences of individual whales by collection of photo-identifications and observation of feeding events. Two moored hydrophones were also deployed the same summer to monitor cetacean occurrence in the area and effects of vessel noise (National Progress Report Iceland 2018).

Norway

During line-transect surveys dedicated to monitor cetacean abundance across the Norwegian Sea during the summer months, the Institute of Marine Research (IMR, Bergen, Norway) records killer whale occurrence and produce updated data about killer whale distribution and abundance in these waters (e.g. Nøttestad et al., 2015).

The Norwegian Orca Survey

The Norwegian Orca Survey (Andenes, Norway), a non-profit research organisation established in 2013, is dedicated to long-term monitoring of killer whales occurring off Northern Norway. Main goals consist in studying population abundance, foraging ecology and habitat use. The ongoing research also aims at continuing the photo-identification study initiated by colleagues in 1986 (Similä et al., 1996; Vongraven and Bisther, 2013). As part of this project, efforts have been directed towards further data collection throughout the year in Northern Norway. This includes collection of ID-photographs, biopsy samples, behavioral observations, aerial (drone) imagery, sound recordings and prey remains. Data are being used for various studies based on individuals’ recognition including mark-recapture analyses and investigations of group-specific foraging ecology. The Norwegian killer whale identification database is a work in constant progress and the latest version of the ID-catalogue was published in March 2018 (Jourdain & Karoliussen 2018).

The Whaletrack project

The Arctic University of Norway (UiT, Tromsø, Norway) conducted tagging experiments on killer whales during the winter months in 2015-2017. The Whaletrack project was initiated in 2013 with the aim to map the humpback and killer whale behaviour and migrations related to their winter aggregations in the Northern Norwegian fjords. In 2018 the Whalefeast project was also included under the Whaletrack framework. The UiT Arctic University of Norway is the project leading institution with close cooperation with the Institute for Marine Research (IMR, Tromsø and Bergen). The project also includes close cooperation with other Norwegian and international institutions and include several PhD- and MSc candidates.

The main purpose of the project is to gain better knowledge about the behavior of humpback and killer whales before, during and after the period they feed on overwintering herring in the fjords or off the coast of Northern Norway. Whilst the Whaletrack project has focused on mapping the horizontal and vertical migration patterns of humpback and killer whales, the new Whalefeast project (2018-2021) will also include a closer cooperation with the fisheries and tourism industry, as well as using eDNA-techniques in addition to already collected data. It will include social science studies of the impacts that the whale arrivals have and have had on the tourist and fisheries industries (National Progress Report Norway 2018).

Ocean Sounds

Ocean Sounds is a non-profit organisation focusing on the biology, acoustics and education about whales and dolphins in several locations worldwide, including killer whales occurring in the Lofoten region in Norway.

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