| Shearwaters | |
|---|---|
 | |
| Great shearwater | |
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Aves |
| Order: | Procellariiformes |
| Family: | Procellariidae |
| Diversity | |
| Genera | |
Shearwaters are medium-sized long-winged seabirds in the petrel family Procellariidae. They have a global marine distribution, but are most common in temperate and cold waters, and are pelagic outside the breeding season.
These tubenose birds fly with stiff wings and use a "shearing" flight technique (flying very close to the water and seemingly cutting or "shearing" the tips of waves) to move across wave fronts with the minimum of active flight. This technique gives the group its English name. [1] Some small species, like the Manx shearwater are cruciform in flight, with their long wings held directly out from their bodies.
Many shearwaters are long-distance migrants, perhaps most spectacularly sooty shearwaters, which cover distances in excess of 14,000 km (8,700 mi) from their breeding colonies on the Falkland Islands (52°S 60°W) to as far as 70° north latitude in the North Atlantic Ocean off northern Norway, and around New Zealand to as far as 60° north latitude in the North Pacific Ocean off Alaska. A 2006 study found individual tagged sooty shearwaters from New Zealand migrating 64,000 km (40,000 mi) a year, [2] which gave them the then longest known animal migration ever recorded electronically (though subsequently greatly exceeded by a tagged arctic tern migrating 96,000 km (60,000 mi) [3] ). Short-tailed shearwaters perform an even longer "figure of eight" loop migration in the Pacific Ocean from Tasmania to as far north as the Arctic Ocean off northwest Alaska. They are also long-lived: a Manx shearwater breeding on Copeland Island, Northern Ireland, was (as of 2003/2004) the oldest known wild bird in the world; ringed as an adult (when at least 5 years old) in July 1953, it was retrapped in July 2003, at least 55 years old (also now exceeded, by a Laysan albatross). Manx shearwaters migrate over 10,000 km (6,200 mi) to South America in winter, using waters off southern Brazil and Argentina, so this bird had covered a minimum of 1,000,000 km (620,000 mi) on migration alone.
Following the tracks of the migratory Yelkouan shearwater has revealed that this species never flies overland, even if it means flying an extra 1,000 km. For instance, during their seasonal migration towards the Black Sea they would circumvent the entire Peloponnese instead of crossing over the 6 km Isthmus of Corinth. [4]
Shearwaters come to islands and coastal cliffs only to breed. They are nocturnal at the colonial breeding sites, preferring moonless nights to minimize predation. They nest in burrows and often give eerie contact calls on their night-time visits. They lay a single white egg. The chicks of some species, notably short-tailed and sooty shearwaters, are subject to harvesting from their nest burrows for food, a practice known as muttonbirding, in Australia and New Zealand.
They feed on fish, squid, and similar oceanic food. Some will follow fishing boats to take scraps, commonly the sooty shearwater; these species also commonly follow whales to feed on fish disturbed by them. Their primary feeding technique is diving, with some species diving to depths of 70 m (230 ft). [2]
There are about 30 species: a few larger ones in the genera Calonectris and Ardenna and many smaller ones in Puffinus . Recent genomic studies show that Shearwaters form a clade with Procellaria , Bulweria and Pseudobulweria . [5] This arrangement contrasts with earlier conceptions based on mitochondrial DNA sequencing. [6] [7] [8]
The group contains 3 genera with 32 species. [9]
There are two extinct species that have been described from fossils.
Phylogeny of the shearwaters based on a study by Joan Ferrer Obiol and collaborators published in 2022. Only 14 of the 21 recognised species in the genus Puffinus were included. [10]
Petrels are tube-nosed seabirds in the phylogenetic order Procellariiformes.
The family Procellariidae is a group of seabirds that comprises the fulmarine petrels, the gadfly petrels, the diving petrels, the prions, and the shearwaters. This family is part of the bird order Procellariiformes, which also includes the albatrosses and the storm petrels.
The Balearic shearwater is a medium-sized shearwater in the seabird family Procellariidae. Puffinus is a Neo-Latin loanword based on the English "puffin" and its variants, that referred to the cured carcass of the fat nestling of the Manx shearwater, a former delicacy. The specific mauretanicus refers to Mauretania, an old name for an area of North Africa roughly corresponding to Morocco and Algeria. The Balearic Shearwater is listed critically endangered by the IUCN and is one of Europe's most endangered seabirds.
The great shearwater is a large shearwater in the seabird family Procellariidae. It breeds colonially on rocky islands in the south Atlantic. Outside the breeding season it ranges widely in the Atlantic.
The sooty shearwater is a medium-large shearwater in the seabird family Procellariidae. In New Zealand, it is also known by its Māori name tītī, and is harvested by Māori people for muttonbird, like its relatives the wedge-tailed shearwater and the Australian short-tailed shearwater.
The little shearwater is a small shearwater in the petrel family Procellariidae. Despite the generic name, it is unrelated to the puffins, which are auks, the only similarity being that they are both burrow-nesting seabirds.
The yelkouan shearwater, Levantine shearwater or Mediterranean shearwater is a medium-sized shearwater in the seabird family Procellariidae. It was formerly treated as a subspecies of the Manx shearwater.
Puffinus is a genus of seabirds in the order Procellariiformes that contains about 20 small to medium-sized shearwaters. Two other shearwater genera are named: Calonectris, which comprises three or four large shearwaters, and Ardenna with another seven species.
Calonectris is a genus of seabirds. The genus name comes from Ancient Greek kalos, "good" and nectris, "swimmer".
Bulweria is a genus of seabirds in the family Procellariidae named after English naturalist James Bulwer. The genus has two extant species, Bulwer's petrel and Jouanin's petrel. A third species, the Olson's petrel, became extinct in the early 16th century; it is known only from skeletal remains. Bulwer's petrel ranges in the Atlantic, Indian and Pacific Oceans, whereas Joaunin's petrel is confined to the northwestern Indian Ocean. Olson's petrel is known from the Atlantic.
The wedge-tailed shearwater is a medium-large shearwater in the seabird family Procellariidae. It is one of the shearwater species that is sometimes referred to as a muttonbird, like the sooty shearwater of New Zealand and the short-tailed shearwater of Australia. It is found throughout the tropical Pacific and Indian Oceans, roughly between latitudes 35°N and 35°S. It breeds on the islands off Japan, on the Islas Revillagigedo, the Hawaiian Islands, the Seychelles, the Northern Mariana Islands, and off Eastern and Western Australia.
The short-tailed shearwater or slender-billed shearwater, also called yolla or moonbird, and commonly known as the muttonbird in Australia, is the most abundant seabird species in Australian waters, and is one of the few Australian native birds in which the chicks are commercially harvested. It is a migratory species that breeds mainly on small islands in Bass Strait and Tasmania and migrates to the Northern Hemisphere for the boreal summer.
Procellaria is a genus of Southern Ocean long-winged seabirds related to prions, and within the order Procellariiformes. The black petrel ranges in the Pacific Ocean, and as far north as Central America. The spectacled petrel is confined to the Atlantic Ocean, and the Westland petrel to the Pacific Ocean. The white-chinned and grey petrel range throughout the higher latitudes of the Southern Ocean.
The flesh-footed shearwater is a medium-sized shearwater. Its plumage is black. It has pale pinkish feet, and a pale bill with a distinct black tip. Together with the equally light-billed pink-footed shearwater, it forms the Hemipuffinus group, a superspecies which may or may not have an Atlantic relative in the great shearwater. These large shearwaters are among those that have been separated into the genus Ardenna. Recent genetic analysis indicates evidence of strong divergence between Pacific colonies relative to those in South and Western Australia, thought to be explained by philopatry and differences in foraging strategies during the breeding season.
The pink-footed shearwater is a species of seabird. The bird is 48 cm (19 in) in length, with a 109 cm (43 in) wingspan. It is polymorphic, having both darker- and lighter-phase populations. Together with the equally light-billed flesh-footed shearwater, it forms the Hemipuffinus group, a superspecies that may or may not have an Atlantic relative in the great shearwater. These are large shearwaters which are among those that could be separated in the genus Ardenna.
Pseudobulweria is a genus of seabirds in the family Procellariidae. They have long been retained with the gadfly petrel genus Pterodroma despite morphological differences. Mitochondrial DNA cytochrome b sequence analysis has confirmed the split out of Pterodroma and places the genus closer to shearwaters. They thus represent either a plesiomorphic lineage still sharing some traits of the ancestral Procellariidae with the gadfly petrels, or convergent evolution of a shearwater to the ecological niche of gadfly petrels.
Ardenna is a genus of seabirds in the family Procellariidae. These medium-sized to large shearwater species were formerly included in the genus Puffinus.