Habitat preferences
The species generally occurs in oceanic habitat over 500 m depth, with a general preference for 800 to 1800 m depth over the continental slope (Whitehead and Hooker 2012). Resident populations may be associated with topographic features such as canyons (Hooker et al. 2002). Where deep waters occur close to the coast of volcanic islands then the species may be encountered within a few kilometres of land, for example around the Azores archipelago (Silva et al. 2014).

Seasonal movements
Resident populations with high site fidelity occur in some geographic areas in the western Atlantic (Hooker et al. 2002). It remains uncertain whether or not the species exhibits similar year-round fidelity to topographic features in the eastern Atlantic. There is some evidence from capture, stranding and sighting records to support seasonal migrations in the eastern North Atlantic, comprising a northward movement during spring and early summer, and a southward movement again from July through the autumn. For example, peak numbers occur in the waters between Svalbard, Iceland and mainland Norway between April and June (Øien and Hartvedt 2011), in the Faroe Islands during August and September (Bloch et al. 1996), and in Ireland and the U.K. of Great Britain and Northern Ireland during late summer and autumn (Berrow et al. 2010, Rogan and Hernandez-Milian 2011, Fernández et al. 2014, Kowarski et al. 2018). However, there are records year-round in those areas, and in the Azores at the southern limit of the species’ distribution it occurs from June to August (Silva et al. 2014). Consequently, the observed seasonality may be alternatively explained by localised inshore-offshore movements rather than marked latitudinal migrations (Whitehead and Hooker 2012, Silva et al. 2014). Nevertheless, the species is capable of making extensive latitudinal movements, as indicated by an individual tagged at Jan Mayen Island in June which moved south to arrive in the Azores in August (Miller et al. 2015).

Diving capabilities
Tagging studies have revealed that the species is one of the deepest-diving mammals, regularly diving to over 800 m depth on foraging dives lasting over an hour (Hooker and Baird 1999). Many of those dives may reach the seabed. The longest and deepest dive recorded for the species to date was a 94 min dive to a depth of 2,339 m at Jan Mayen, although that dive may not reflect undisturbed behaviour (it occurred during sonar trials: Miller et al. 2015). Between dives, groups may spend considerable time at the surface, resting and socialising.

Diet
In the eastern North Atlantic, Northern Bottlenose Whales feed primarily on squid but also take some fish such as redfish (Sebastes sp.) and Greenland halibut (Reinhardtius hippoglossoides: Benjaminsen and Christensen 1979). They capture prey using suction feeding. They particularly favour squid from the Gonatus genus, which are abundant in cold water in epipelagic and bathypelagic habitat (Mead 1989, Bloch et al. 1996, Whitehead and Hooker 2012). The stomach contents of two animals stranded in the North Sea, and one in the Baltic Sea, predominantly contained Gonatus species based on prey weight (Lick and Piatkowski 1998, Santos et al. 2001). Other squid species are also taken: at least 21 species were recorded in the stomachs of 10 animals stranded in Ireland, the UK and the Netherlands, although Gonatus spp., Teuthowenia spp. and Taonius pavo dominated by weight and number (Fernández et al. 2014). One animal stranded in the Bay of Biscay had predated two species of cephalopod: the squid Teutowenia megalops and the oceanic octopod Stauroteuthis syrtensis (Spitz et al. 2011).

Group size and composition
In Icelandic, Faroese and Jan Mayen waters, groups of 1-5 animals are most commonly sighted (Pike et al. 2019, Jakobsdóttir 2021). Exceptionally, larger groups of 20+ animals are seen around Jan Mayen (Jakobsdóttir 2021). In southern Europe, the average group size in the Bay of Biscay was 3.5 animals (Kiszka et al. 2007) and in the Azores was 5.7 animals (Silva et al. 2014). Groups usually comprise a mix of age and sex classes.

Global
The Northern Bottlenose Whale is endemic to the North Atlantic, where it primarily occupies oceanic habitats (MacLeod et al. 2006). Its main distribution extends from warm temperate regions at around 38ºN all the way to the ice edges, but it is most abundant in cold temperate zones and sightings south of 55ºN are relatively less common (Whitehead and Hooker 2012). In the western Atlantic its regular distribution occurs from New England (USA) north to Baffin Island (Canada), and in the eastern Atlantic it is found from the Azores (Portugal) north to Svalbard (Norway). It also occurs off the east coast of southern Greenland in the central North Atlantic (Benjaminsen and Christensen 1979, Pike et al. 2019). Strandings of the species have occurred further south of the core distribution range, including southern limits in Virginia (36ºN, USA: Waring et al. 2015) and the Canary Islands (29ºN, Spain: Martín et al. 2011).

European
Within the European assessment region, the species is considered rare in Russian Federation waters; one stranding was documented at the Rybachy Peninsula in 2012, but it is primarily distributed in deeper water to the west of the shallow Barents Sea (Mishin 2021). Whalers concentrated their efforts for the species in four core areas of abundance at higher latitudes: (1) a broad region off east Greenland, around Iceland, Jan Mayen and the Faroe Islands; (2) south-west of Svalbard (Norway); (3) off Andenes in northern Norway; and (4) off Møre in western Norway (Benjaminsen and Christensen 1979, Mead 1989, Øien and Hartvedt 2011, Whitehead and Hooker 2012). Although numbers are depleted post-whaling, these areas remain important for the species, with sighting surveys and incidental reports documenting a regular contemporary occurrence of the species in the deep waters located between Svalbard, Jan Mayen, Iceland, the Faroe Islands and mainland Norway (Øien and Hartvedt 2011, Miller et al. 2015, Storrie et al. 2018, Pike et al. 2019, Leonard and Øien 2020), with occasional forays into coastal shelf areas (e.g. Bloch et al. 1996, Grove et al. 2020).

It also inhabits the deep waters located offshore to the north and west of Ireland and the U.K. of Great Britain and Northern Ireland, including the Faroe-Shetland Channel, the Rockall Trough, the slope around the Porcupine Bank, and the Porcupine Seabight (Weir et al. 2001, Skov et al. 2002, Rogan et al. 2017, 2018, Kowarski et al. 2018). Occasional live sightings of the species occur in coastal waters in this area, particularly during August and September, but are considered strays (Berrow et al. 2010). Strandings, including live animals and mass events, have been documented along the North Sea coasts of the United Kingdom (MacLeod et al. 2004), Denmark (Kinze et al. 2018), Germany (Kinze et al. 2021), and The Netherlands (Kastelein and Gerrits 1991). However, that area comprises shallow waters and is not considered part of the normal distribution range. Similar is true of rare strandings on the Swedish, Danish and German coasts of the Baltic Sea (Lick and Piatkowski 1998, Santos et al. 2001, Kinze et al. 2018). It has been proposed that animals accidentally enter the North Sea during their southward migration, becoming trapped in the shallow habitat and eventually stranding (MacLeod et al. 2006). Northern Bottlenose Whales are the most common of the beaked whale species to strand in Ireland, with most records occurring along the Atlantic seaboard (Rogan and Hernandez-Milian 2011).

There have been a small number of strandings reported along the French coasts of the English Channel and the Bay of Biscay since 1969 (Réseau National Échouages: www.observatoire-pelagis.cnrs.fr). Sightings sometimes occur in deep waters of the Bay of Biscay off northern Spain (Kiszka et al. 2007, Robbins et al. 2022). There are occasional sightings in deep water off mainland Portugal (Bencatel et al. 2019). The species is considered to be fairly common in deep water areas around the Azores (Silva et al. 2014). It is rare further south of the Iberian Peninsula and the Azores. There are only two confirmed records in the Mediterranean Sea where it is considered vagrant (Pace et al. 2015), comprising a stranding of a mother and calf near Montpellier (France) and a live sighting in the Alboran Sea region of Spain (ACCOBAMS 2021). Eleven years of survey effort off the south coast of Madeira produced one confirmed sighting of six animals (Ferreira et al. 2017, Alves et al. 2018), and several unconfirmed sightings (Freitas et al. 2012). The southernmost record of the species in European assessment area is a stranding at Fuerteventura in the Canary Islands (Martín et al. 2011).