In the North Atlantic, Fin Whales feed predominantly on Northern Krill (Meganyctiphanes norvegica) (Aguilar 1985, Sigurjónsson and Víkingsson 1997, Ryan et al. 2014). However, other zooplankton species or schooling fish, e.g. capelin Mallotus villosus, Sand Lance Ammodytidae, Blue Whiting Micromesistius poutassou, Sprat Sprattus sprattus, Herring Clupea harengus, Mackerel Scomber scombrus, or smaller squids can be a part of their diet (Christensen et al. 1992, Sigurjónsson and Víkingsson 1997, Ryan et al. 2014, Aguilar and García-Vernet 2018). In Icelandic catches, 96% contained krill only, 2.5% a mixture of krill and fish, and 1.6% fish only (Sigurjónsson and Víkingsson 1997).

In the Mediterranean Sea, Fin Whales have been observed engaging in feeding throughout the year as summarised by Notarbartolo di Sciara et al. (2016): a majority of observations from summer in the Ligurian Sea, off eastern Sicily and in the southern Tyrrhenian Sea; feeding whales were also seen in spring off eastern Sicily as well as in winter off northeastern Sardinia and in the Strait of Sicily. Their main prey is also Northern Krill (Bentaleb et al. 2011, Das et al. 2017), but some individuals have been observed feeding on another euphausiid Nyctiphanes couchii (Canese et al. 2006).

Wintering grounds are largely unknown (Aguilar and García-Vernet 2018). Some whales are known to stay at high latitudes year-round (Charif and Clark 2009), while others might disperse to poorly surveyed open waters where they are more difficult to detect. Whales have been recorded acoustically off SW Portugal acoustically from September to April (Pereira et al. 2020) and in the area of the Strait of Gibraltar in autumn-winter (Castellote et al. 2012a). These could be related to the winter migration into the Mediterranean by whales that had been feeding in Northeast Atlantic feeding grounds (Gauffier et al. 2018, 2020). Newborn and small calves have been observed in the Mediterranean Sea and mothers with calves were seen migrating through the Strait of Gibraltar towards the Atlantic during May-July, suggesting that the Mediterranean Sea is a winter breeding ground for the Mediterranean subpopulation (Notarbartolo di Sciara et al. 2003, Gauffier et al. 2018). Calves have been found stranded in NW Spain in winter in the last decade (Gauffier et al. 2020) and are observed occasionally in Madeira (Alves et al. 2018).
Fin whales feed intensively during the summer, when adult whales can consume up to 1 ton of euphausiids per day, and mostly fast during the winter (Aguilar and García-Vernet 2018).

Fin Whales occur worldwide, mainly, but not exclusively, in offshore waters of the temperate and subpolar zones (Edwards et al. 2015). They are rare in the tropics, except in certain cooler-water areas such as off Peru.

North Atlantic
In the North Atlantic Ocean, the Fin Whale's range extends as far as Svalbard in the northeast (but rarely far into the Barents Sea), to the Davis Strait and Baffin Bay in the northwest (but rarely into the inner Canadian Arctic), to the Canary Islands in the southeast, and to the Antilles in the southwest (Rice 1998, Perry et al. 1999), but it is rare in the Caribbean and Gulf of Mexico (Ward et al. 2001).

While there may be some north-south migration between summer and winter, it does not necessarily involve the entire population, and North Atlantic Fin Whales may occur to some extent throughout the year in all of their range, as suggested by acoustic data (Clark 1995).

They occur in summer (and possibly year-round) west and east of Greenland, around Iceland and the Faroe Islands and along the Iceland-Faroes ridge (Víkingsson et al. 2009), and to a lesser extent in the Norwegian Sea and around Jan Mayen (Øien 2009). They occur off the northern and western British Isles and in the Bay of Biscay off northwestern Spain but are rare in the North Sea (Hammond et al. 2021). Fin whales are regularly sighted in coastal waters of the Celtic Sea as well as along the edge of the Irish continental shelf and adjacent waters, with higher densities near the coast in autumn and winter (Whooley et al. 2011, Baines et al. 2017, Rogan et al. 2018). Passive acoustics arrays covering deep waters adjacent to the continental shelf break from the North of the British Isles to the north of the Iberian Peninsula detected Fin Whale calls all year long with a seasonal pattern from peak densities in December-January to minimal levels in May-June (Charif and Clark 2009). Within the Bay of Biscay Fin Whales are more abundant in the southern part in July (Hammond et al. 2011, 2021) and high densities are also found in the south‐eastern part in September (García-Barón et al. 2019). They regularly occur off the Azores in spring (Visser et al. 2011, Silva et al. 2013) and are observed occasionally in Madeira in autumn-winter (Freitas et al. 2012). An increase of Fin Whale sightings was observed in summer 2022 in Madeira (L. Freitas pers. comm. 2022). Few whales are observed in the Canary Islands (Pérez-Vallazza et al. 2008, Carrillo et al. 2010).

Limited Fin Whale strandings occur along the Moroccan Atlantic coast (Masski and de Stéphanis 2018), and few whales were sighted off Mauritania (Baines and Reichelt 2014) and in winter in the Cabo Verde archipelago (Moore et al. 2003).

Mediterranean
The Fin Whale is the only common baleen whale species in the Mediterranean Sea and is present in the central and western basin. The area of abundance seems to be concentrated in the Ligurian Sea and the Gulf of Lyon in summer, but expands to cover much of the western and central Mediterranean in winter (Notarbartolo di Sciara et al. 2003). Fin Whales are rare in the southern and eastern Mediterranean, do not penetrate far into the Adriatic or Aegean Seas, and are not present in the Black Sea. In the 1920s and 1950s century, Fin Whales were caught year-round in the Gulf of Cadiz, on the western side of the Strait of Gibraltar (Sanpera and Aguilar 1992). Contemporary observations from the 2000-2010s show Fin Whales leaving the Mediterranean through the Strait of Gibraltar during May-October and (mostly) entering the Mediterranean during November-April (Gauffier et al. 2018); the observations of calves leaving the Mediterranean during May-July suggest they were born there. Two different song patterns were recorded through passive acoustics in the Mediterranean Sea and contiguous Gulf of Cadiz over several years, including spatiotemporal differences and overlap (Castellote et al. 2012, Sciacca et al. 2015, Pereira et al. 2020). However, all whales sampled in the Mediterranean Sea and Strait of Gibraltar were attributed to the Mediterranean subpopulation by genetic analyses (Bérubé et al. 1998, Schleimer et al. in prep., see 'Population'). Some considerations regarding the implications for the status of the Mediterranean subpopulation are detailed in Panigada et al. (2021).

Their overall range is well above the application of criteria B.

Catch limits for all commercial whaling have been set at zero by the IWC since 1986. However, Iceland registered a reservation to this moratorium, so that it does not apply to their coastal catches that resumed since 2006. Limited aboriginal subsistence whaling is permitted by the IWC for Fin Whales taken off West Greenland, with a quota of 19 whales per year.

Fin Whales are listed on Appendix I of the Convention on Trade in Endangered Species (CITES), but this does not apply to Iceland, Norway and Japan, who hold reservations. Fin Whales are also listed on Appendices I and II of the Convention on Migratory Species (CMS) and are protected the Agreement for the Conservation of Cetaceans in the Black Sea, Mediterranean Sea and contiguous Atlantic area (ACCOBAMS https://accobams.org/). They are listed in Annex 2 of the Protocol on Specially Protected Areas and the Biological Diversity in the Mediterranean of the Barcelona Convention and Appendix II of the Bern Convention.

The international Pelagos Sanctuary for Mediterranean Marine Mammals, covering important Fin Whale habitat, was established in 1999 between France, Italy and Monaco and listed among Specially Protected Areas of Mediterranean Importance (SPAMIs). Whale-watching regulations in the area have been recommended by ACCOBAMS. A new Spanish marine protected areas and SPAMI “Corredor de Migración de Cetáceos del Mediterráneo” was declared in 2018 between the Balearic Islands and the Iberian Peninsula. In this area, all seismic surveys and oil and gas exploitation are prohibited. Important Marine Mammal Areas (IMMAs) for Fin Whales have also been identified in the Mediterranean Sea, possibly leading to the proposal for the establishment of Marine Protected Areas and/or helping to identify areas of high risk for ship strikes, where appropriate and dedicated mitigation measures can be suggested (IWC 2019).

Fin Whales could benefit from the modification of the traffic separation scheme (TSS) implemented in the Gibraltar Strait in 2007, including a security area where crossing ships are recommended to limit their speed to 13 knots or slower (Instituto Hidrográfico de la Marina, Ministry of Defence, Spain). However, there is no evidence of compliance by mariners (Silber et al. 2012) and this measure is only seasonal (April-August) so migrating Fin Whales that use this area in both summer and winter are effectively unprotected for more than half of the year (Gauffier et al. 2018).