Christmas shearwater  (Puffinus nativitatis)

The Christmas shearwater is classified as Least Concern (LC) on the IUCN Red List (1).

A medium-sized, slender-bodied shearwater of the Procellidae family, the Christmas shearwater (Puffinus nativitatis) has a uniformly sooty black-brown colouration. It is somewhat darker on the head, upperwings and tail, while the throat, neck and underparts generally appear slightly paler (2) (3) (4). The undersides of the primaries and the tail often have a dull, silvery sheen, and the feathers on the chin are sometimes edged with white. The tail is wedge-shaped. The Christmas shearwater has a relatively short, narrow and slightly hooked black bill, and the legs and feet are greyish-brown with black on the outer sides (2) (3) (4). The male, female and juvenile Christmas shearwaters are similar in appearance (2).

As in other shearwaters, the legs of the Christmas shearwater are set far back on its body and it moves with an awkward, waddling gait on land, often shuffling along on its breast. When airborne, the Christmas shearwater appears much more elegant, typically flying with fast, stiff wing beats followed by long buoyant glides, close to the surface of water (2).

The Christmas shearwater is a fairly vocal seabird, often calling with a particularly distinctive, rolling note, followed by three short notes and a long, drawn-out moan. This species is often observed calling when flying together as a pair, and its calls are typically related to courtship and territory defence (2) (5).

The Christmas shearwater breeds on remote islands in the Central Pacific (2) (3) (4) (5) (6), including the Hawaiian Islands, Christmas Island, Phoenix Island, the Pitcairn and Marquesas Islands, French Polynesia, Tuamotu Islands, Marshall Islands, Austral Islands, Society Islands and Easter Island (2) (6).

Outside of the breeding season, the Christmas shearwater ranges across the Pacific Ocean, from Mexico to Chile in the east and the Bonin Islands in the west (3) (6).

The Christmas shearwater typically breeds on remote oceanic islands, nesting on the ground under dense vegetation or in rocky crevices. It may also use steep, grass-covered slopes and abandoned burrows, and may nest under wooden debris and occasionally buildings (2) (4).

A highly pelagic species, the Christmas shearwater spends the majority of its time out at sea, generally avoiding land except during the breeding season. Its diet consists mainly of the larval forms of fish and squid, although crustaceans are also sometimes taken. Generally, the Christmas shearwater forages in association with other seabirds, consuming prey that has been driven to the surface by schools of predatory fish such as skipjack tuna (Katsuwonus pelamis). It catches food primarily by plunging or diving into the water in pursuit of prey, although it may also seize food while sitting on the surface, or by dipping and picking prey from the water while in flight (2) (3) (4) (6).

Like most shearwaters, the Christmas shearwater returns to its natal colony to breed (4). The breeding season generally begins around February, when breeding birds return to nesting colonies and begin courtship and pair formation (2) (3). The nest is generally a shallow depression in the ground or a simple nest of small twigs and leaves (2) (3) (4).

The Christmas shearwater lays a single, large white egg, which is incubated for around 50 to 54 days. The adult shearwaters take turns to incubate, in shifts which typically last for four to five days (2) (3). The chick remains in the nest until it fledges at around 100 to 115 days old. Both adult Christmas shearwaters care for the chick until it has fledged, providing food to the chick around once every 24 hours by feeding it with stomach oil and partially digested fish (2) (3) (4).

The Christmas shearwater is not currently considered to be threatened with extinction (1).

However, introduced and invasive species threaten Christmas shearwater populations by predating the eggs, chicks and adults, as well as by causing habitat degradation and increasing competition for space and suitable nesting locations. In addition, human activities such as development and recreation close to nesting colonies may threaten the Christmas shearwater by causing disturbance to nesting birds and resulting in increased nest desertion (2).

Other threats to the Christmas shearwater include its exploitation for food on some Pacific islands, as well as pollution, ingestion of plastics, which may lead to starvation, and increasing levels of light pollution, which may cause the Christmas shearwater to become disorientated and confused. Collision with longline fishing gear is a major cause of mortality, while overfishing of important predatory fish may lead to reduced foraging success of seabirds such as the Christmas shearwater, which rely on larger fish to drive prey to the surface (2).

Climate change, in particular rising sea levels, is also likely to affect Christmas shearwater populations in the future, as many colonies exist on small, low-lying oceanic islets which are increasingly at risk from exceptional weather and ocean events such as El Niño, hurricanes, typhoons, and tsunamis (2). 

The Christmas shearwater is included on the Migratory Bird Treaty Act in the U.S., which prohibits taking protected species, their nests or eggs except where permitted by regulation (7). The U.S. Fish and Wildlife Service has identified several management goals important to Pacific seabird conservation, including the need to maintain, protect and enhance habitat, eradicate or control non-native species, and minimise bycatch and other negative effects of fishing (4) (8).

Invasive predator removal programmes have been initiated in some parts of the Christmas shearwater’s range, such as a rat eradication project on Midway Atoll which involved a combination of intensive trapping and poisoning on the entire island. In the two years following the removal of rats from the island, the shearwater population increased from just 50 nesting pairs to almost 200 nesting pairs (2). Predator removal at other important nesting sites, such as Christmas and Ducie Islands, would also benefit the Christmas shearwater and other ground-nesting seabirds (2) (4).

Habitat restoration projects, such as those on Midway Atoll and Laysan Island, are removing invasive introduced vegetation and replacing it with native species to increase the amount of appropriate nesting habitat for seabird species (2).

Research priorities for the Christmas shearwater include determining an accurate and up-to-date worldwide population estimate to help monitor the stability of populations in the Pacific, establishing the location of important feeding grounds and the shearwater’s non-breeding range, and assessing the indirect impacts of overfishing and the growing tuna fishing industry on Christmas Shearwater foraging success (2) (4).

ARKive is supported by OTEP, a joint programme of funding from the UK FCO and DFID which provides support to address priority environmental issues in the Overseas Territories, and Defra

Find out more about the Christmas shearwater:

• The Birds of North America Online - Christmas shearwater (Puffinus nativitatis):
  http://bna.birds.cornell.edu/bna/species/561
• Neotropical Birds Online - Christmas shearwater (Puffinus nativitatis):
  http://neotropical.birds.cornell.edu/portal/species/overview?p_p_spp=102396

Find out more about the Christmas shearwater and other birds:

• BirdLife International:
  http://www.birdlife.org/