Bird of the Month: Pink-footed Shearwater
Written by Andy McCormick
Andy McCormick, Volunteer and Former Board President of Eastside Audubon
Pink-footed Shearwater
Scientific Name: Puffinus creatopus
Length: 18”
Wingspan: 44”
Weight: 1.6 lb (720g)
AOU Alpha Code: PFSH
One of the most common seabirds seen several miles off the coast of Washington from April to November, the Pink-footed Shearwater is rarely seen from shore. It disperses north from its breeding grounds off Chile spending the austral winter in the northern hemisphere. It follows the continental shelf eating fish and squid migrating as far north as Alaska.
SLOPE-SOARING
“A big, floppy, western shearwater with a gentle expression. …Flight is heavy and sluggish. Wingbeats are languid and floppy…punctuated by often very lengthy glides.” (Dunne). The Pink-footed is one of the larger shearwaters and tends to glide longer than most of the others. This type of gliding is typical of seabirds and is described as “slope soaring” (Sibley). As a wave moves through the water it forces air ahead of it. This creates a small updraft which seabirds use to stay aloft with no wing flapping. It allows seabirds to travel tremendous distances with minimal effort, essentially surfing on the air above the wave (Sibley).
TUBENOSE
The shearwaters are part of the large family Procellariidae also called the “tubenoses.” They have two tubes along their bill which house the nostrils. These birds have an advanced sense of smell and use this sense to search for food in the vast ocean. They are often attracted to fishing boats and pelagic birding trip leaders often throw chum, a mixture of fish oil and body parts, into the ocean to attract them for close viewing.
The genus name, “Puffinus is an English word applied in the seventeenth century to the razorbill, shearwater and puffin” (Holloway). This genus name is now used only for shearwaters. The species name “creatopus, flesh footed,[is] from the Greek kreas, flesh…and… pous, foot. [The] reference is to the pink feet, seen in flight against a mottled gray tail” (Holloway). The feet can be seen at close range, but identification of seabirds is most often made by body shape, overall color pattern, and flight style, a skill that is developed only by field experience.
Pink-footed Shearwaters nest on islands off Chile. Little research has been done, but what we do know is that they dig out a burrow, sometimes as long as four feet, in which a single egg is deposited on the ground in early December (Kaufman). We do not know the incubation period, but young birds leave the nest in April when the colonies break up and northern migration begins.
CONSERVATION AND MANAGEMENT
Greater awareness of threats to seabirds is helping scientists determine ways to protect them. The Pink-footed Shearwater is listed as vulnerable by the International Union for the Conservation of Nature, and as threatened in Canada and Chile. There are threats to the breeding colonies from the introduction of mammals such as rats, pigs, and coatis. Seabirds also end up as by-catch to long-line and gill net fishing at sea. Conservation measures are needed to eradicate predators from the breeding colonies and regulate deep sea fishing. A new threat from overfishing of forage fish such as the sand lance, juvenile herring, and smelts is reducing available food sources for seabirds.
Photo credit Julio Mulero (banner) and Tom Benson.
References available upon request from amccormick@eastsideaudubon.org.