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Black-footed Albatross (Phoebastria nigripes)
By Peter Winch
One of the most exciting places to visit in the Gulf of the Farallones Marine Sanctuary is its western boundary, past the islands and beyond the continental shelf, where the wildlife of the coastal waters gives way to the deep ocean ecosystem.
The Black-footed albatross is a large brown seabird that comes to this part of the sanctuary, all the way from Hawaii, to take advantage of the abundant food supply generated by the upwelling of plankton from late spring through late fall.
Mature adults weigh around 3.3 kilos, have brown plumage with black feet and large black bill. The older birds are distinguished by having light gray patches on the back, rump and around the head.
The wings are long and thin and up to seven feet in length. They have evolved for efficient ocean travel, not flapping, but manipulating the winds like a glider. Their skeletal structure enables the wing bones to lock into place, to make soaring and gliding across thousands of miles of ocean as energy efficient as possible.
Black-footed albatross nest on the northwestern Hawaiian Islands. After fledging, they wander the pacific for three years, then return to the islands select a mate, often for life, though there are divorces and separations.
The courtship and mating process starts in November. The courtship ritual is accompanied by an elaborate and noisy mating “dance”. One egg is laid in December, which hatches after a 6 to 8 week incubation period in January or February. Black-footed albatross tend to favor sandy, non-vegetated areas of these islands to lay their eggs.
The chicks are brooded for twenty days by both parents. Afterwards, the parents both leave to gather food and return to feed the chick, regurgitating the food in response to the chick sticking its bill inside the bill of its parents. The adults will go thousands of miles from the islands to find food, visiting the Farallones Sanctuary and the Bering Sea, their foraging trips lasting up to three weeks.
The chick is fed for 140 days, which is a large energetic investment to the parents. This explains the involved mate selection process and monogamous partnership between the parents, forging a bond that is most likely to ensure the survival of their chick through the first six months of its life.
Black-footed albatross are surface feeders, foraging on live and dead marine life that floats on the top of the water or within the top foot of the water column. Squid is a large percentage of their diet, but they are notorious scavengers and often congregate around fishing boats, feeding on offal and by-catch.
They use their excellent sense of smell to find food, their well developed nostrils picking up the scent of fish oil and squid from miles away.
The Black-footed Albatross is a federally listed endangered species with a current population of around 110,000. Probably their biggest threat is from long-lining, a non-specific fishing process where lines of baited hooks (often baited with squid, albatross’s favorite food) are either dragged or left hanging in the water column to attract fish. All three species of northern hemisphere albatross are attracted to the bait, swallow the hooks and drown.
An estimated 1800 were killed annually between 1994 and1998 by the Hawaiian long-lining fishing industry alone. Despite the fisherman’s efforts to prevent this mortality by techniques such as streamers and weighted hooks, long lining persists as the major threat to Black-footed albatross populations.
An additional threat is plastic pollution. Albatross mistake all sorts of floating plastic debris for potential food, ingest it as food, or regurgitate it for their chicks to eat. This can cause mortality in a number of ways.
Firstly, the plastic can rupture the intestinal tract of both the chicks and the adults. Secondly, the volume of the plastic takes up space in the stomach available for real food, leading to malnutrition. Lastly, plastic debris absorbs chemical pollution like pesticides and PCBs that can have a detrimental affect on the albatross.
Seeing an Albatross
Albatross are magnificent birds, and seeing one at sea has long been considered a good omen by mariners. American ornithologist Robert Cushman Murphy once said, “ I now belong to a higher cult of mortals for I have seen the albatross.”
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