This species is exclusively marine, occurring along sea coasts on rocky cliffs and offshore islands. It breeds mainly on steep sea cliffs and low, flat islands. During the winter it is mostly found offshore, along the edge of continental shelf and shallow banks, marine coasts and bays, usually in boreal waters but some birds occur in the cool subtropical zone. The time of breeding is variable and is largely determined by water temperature and ice. Generally egg-laying takes place mid-May to early June and fledging mostly by late July to mid-August. It lays on a broad or narrow cliff ledge and on low, flat islands; occasionally also in crevices, under boulders and in caves. It does not build a nest and lays a single egg on bare rock. It is a pursuit-diving marine bird which forages primarily during daylight (Wanless et al. 1988). During the breeding season, schooling pelagic fish species are the most important prey for adults, though benthic species can also be important. In Labrador, Canada, Shannies (Sicheaidae) were the main source of food, comprising 84% of the diet in 1996 and 52.9% in 1997 (Bryant and Jones 1999). Capelin (Mallotus villosus) were also important, forming 44.7% of the diet in 1997 (Bryant and Jones 1999). In the U.K., the main prey taxa are sandeel (Ammodytes spp.) and clupeids. Small gadoids are also important at some colonies. The species winters mostly within its breeding range with some birds remaining relatively sedentary (Nettleship et al. 2013).

Although the generation length for both EU and Europe regional assessments were calculated using the same methodology, new information arriving after the EU assessments were undertaken gave rise to an update in the generation lengths. This new information was then used for the Europe level assessments giving rise to a difference between the generation lengths used for the EU and Europe regions.

The species is the most widespread of all the auks and has a circumpolar distribution, occurring in the low-arctic and boreal waters of the north Atlantic. In Europe its southern limit reaches the Berlengas Islands (Portugal) (Hagemeijer and Blair 1997) and in the north its range is determined by the ice conditions. 

In Europe, this species breeds primarily in the United Kingdom and Iceland, and also notably in the Faroe Islands.

Conservation Actions Underway
Uria aalge ibericus is found on Annex I of the EU Birds Directive. With the implementation of bird protection laws, a slow recovery occurred over much of the Atlantic breeding range up to early 1970s except in north Norway and probably Iceland (Nettleship et al. 2018).

Conservation Actions Proposed
At major colonies, detailed monitoring is needed, particularly in Iceland, where the status of the largest Atlantic population is poorly known (Nettleship et al. 2018). The impact of bycatch in fish nets can be reduced in several ways: Protecting areas on a seasonal and/or diurnal scale; concentrating salmon fisheries when salmon densities are high to improve fishing efficiency and catch to bycatch ratios; changing to an alternative fishing technique may reduce seabird mortality; and gear modification (Österblom et al. 2002).