The diving petrels form a genus, Pelecanoides, of seabirds in the family Procellariidae. There are four very similar species of diving petrels, distinguished only by small differences in the coloration of their plumage, habitat, and bill construction. They are only found in the southern hemisphere. The diving petrels were formerly placed in their own family, the Pelecanoididae.

Diving petrels are auk-like small petrels of the southern oceans. The resemblances with the auks are due to convergent evolution, since both families feed by pursuit diving, although some researchers have in the past suggested that the similarities are due to relatedness. Among the Procellariiformes the diving petrels are the family most adapted to life in the sea rather than flying over it, and are generally found closer inshore than other families in the order.

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