Approximately 23 species of petrels feed in the Patagonian Sea, but only the Southern Giant Petrel (Macronectes giganteus) breeds on the coasts of Patagonia. Seven species breed in the Malvinas Islands, one of which is the White-chinned Petrel (Procellaria aequinoctialis). The Northern Giant Petrel (Macronectes halli), a frequent visitor of the Patagonian Sea, breeds at South Georgia.

Most petrels are long-lived species, requiring several years to reach breeding. Their reproductive output is low, producing at most one chick per year. These qualities make them vulnerable to any increase in adult mortality, such as that caused by fisheries. The 3 species for which we present data are under some degree of vulnerability, according to the criteria of IUCN (near threatened and vulnerable).