Where do most procellariiform birds breed?

The majority of procellariiform birds breed in the Southern Hemisphere. These birds typically nest in large, crowded colonies on small islands, where they often compete for nesting territories.12

Depending on the species, nesting habits vary:
* Burrowing: Most shearwaters, diving petrels, and some storm petrels dig burrows in soft soil.2
* Surface and Ledge Nesting: Albatrosses scrape shallow depressions or build mounds of soil and vegetation, while fulmars and other diurnal petrels nest on ledges or level ground.2
* Crevices: Some storm petrels utilize natural crevices.2

While most species are found in the Southern Hemisphere, some breed in the Northern Hemisphere or in tropical and subtropical latitudes. A few species, such as certain shearwaters and larger petrels, even breed far inland on mountain crags.1