A Greater Shearwater (Puffinus gravis) which is amongst the densest of all procellariid, to the tune of two birds in every square meter

Procellariidae is a family of seabirds that is dominant and most populace constituent of the bird order Procellariiformes (tubenoses). This order also includes the majestic albatrosses, the diving petrels and the storm petrels. The Procellariidae family comprises:

• The fulmarine petrels
• The gadfly petrels
• The prions
• The shearwaters

 

Species description

The four groups of Procellariidae family are indeed the most populace family in the order of tubenoses and also the single most diverse one when it comes to species. One key diversity aspect is their ranging sizes. The family includes the giant petrels, a bird as large as the majestic albatrosses. The same family includes the prions, which infinitely small in comparison, as small as storm petrel.

Feeding Habits

The Procellariidae feed on squid, fish and crustacean. Some also depend on the fisheries discards if available and carrion. Nonetheless, all species in the family are accomplished and studious long-distance foragers. They undertake numerous demanding trans-equatorial migrations over long distances depending on the food availability and the climate. Shearwaters are specially adapted to diving deep into the sea after a prey instead of just foraging on the surface.

Habitats

Procellariidae species are present in most, actually in all the world's oceans and seas. However, the northern New Zealand seas are the epicenter of the procellariid biodiversity. Almost all the species are represented here. The fulmarine petrels however have a more polar distribution than the other three groups in the family, with most of their species residing around the Antarctica.

Procellariidae species usually undertake long migrations every year during the non-breeding season towards islands off New Zealand, Australia and Chile. Millions of birds undertake the transequatorial migration across Alaska waters to and fro each austral winter.

Breeding

Procellariidae are colonial breeders who exhibit long-term single mate fidelity. This means that they couple up and remain monogamous all through their lifespan with a tremendous site philopatry. All the species of the Procellariidae exhibit a common breeding pattern. For instance, each pair of the birds lay only a single egg every breeding season. The incubation time of Procellariidae and the chick-rearing period is exceptionally long as compared to many other birds leading to a low increase in their numbers. Some Procellariidae species however have breeding populations exceeding three million pairs while others only number less than 200 breeding birds.

Conclusion

Humans have in the past exploited some species of Procellariidae, notably the fulmar and the shearwater. These two are commonly known as the mutton-birds and they are exploited for fuel, food, bait and sport. The exploitation continues unabated even today, mostly by long-line fisheries. Up to 36 species of the Procellariidae family are threatened while 10 are critically endangered mostly by marine fisheries exploits, water pollution and possibly adverse climate change.

Consequently, several species of the Procellariidae family are threatened. Other mammal predators like feral cats, mongoose, rats and mice introduced of late into their habitats have also attacked adults Procellariidae and their chicks ferociously especially around their breeding colonies.