As the breeding season unfolds on Midway Atoll NWR, hundreds of thousands of Laysan Albatross (Phoebastria immutabilis) flock from the sea to the small sandy atoll to raise their young. Among the returning albatrosses is Wisdom, the world’s oldest known wild bird. Looking across Sand Island of Midway Atoll NWR, you can make out the smooth curvature of dunes based on the black-and-white carpet of albatross that cover the ground. Behind bike racks, lined up along streets, and nestled between bunch grasses, albatross are everywhere. Hosting more than 70% of the world's Laysan Albatross (Phoebastria immutabilis) and almost 40% of the Black-footed Albatross (Phoebastria nigripes), Midway Atoll NWR is one of the world’s largest seabird breeding colonies. All in all, almost 3 million birds from 23 different species breed at Midway. That's equal to about the entire population of the state of Mississippi— all crammed into the tiny 2.4 square miles (6.2 square kilometers) that comprise this national wildlife refuge.
A little more than a month ago, Midway Atoll stood largely empty. It was quiet, save for the waves crashing along North Beach and the wind rustling between native Naupaka Kahakai (Scaevola taccada) shrubs. Now, the wavy landscape is full and alive of albatross. They waddle around with large, clown-like steps on the ground, shuffling past one another to find their mates and nesting spots. Some fly high in the air, barely moving a muscle, and then come in to land with feet out, preparing for the often difficult transition between their realm of the sky and the rocky ground below. Courtship dances break out as well as kerfuffles between neighbors; feathers fly and tempers rise. There are also moments of tenderness; some albatross gently tend to their nests, pulling in small clumps of vegetation and soil, while others sit contently as a pair, one affectionately preening the other. The sounds of the albatross colony continue day and night, a collection of never-ending, high-pitched horse whinnies, moo’s, goose-like calls, and bill snaps and claps galore. Out of all the thousands of Laysan Albatross that have returned to Midway Atoll NWR, one albatross stands out in particular. While she may look identical to her neighbors, she carries unique identification bands on her feet that distinguish her from the rest. Her name is Wisdom. Deemed the oldest known wild bird, Wisdom was banded back in 1956. If she had hatched in that year, she would be 58 now. However, since she was already breeding in 1956, she was estimated to be at least 5 years of age then— making her at least 63 years old now! In fact, it’s quite probable that Wisdom could be older, since Laysan Albatross (like many other seabirds) delay sexual maturity until at least age 5 and may not breed successfully until ages 8 to 10. Why the wait, though? Consider this: a life at sea ain’t easy. Albatross scour the open ocean for hundreds of miles in search of squid or flying fish eggs attached to a piece of pumice— seemingly meager pickings. The situation seems even more sparse when you take into account that the open ocean is also one of the least “productive” places for food resources, specifically in terms of net primary production (NPP), which is the amount of light energy converted into chemical energy minus the energy used by the primary producers (like plants and cyanobacteria) for respiration. In other words, NPP indicates how much energy is available for use (or consumption) by other organisms (ranging from tiny invertebrates to huge whales). In the open ocean, NPP is quite low, averaging about 125 g/m2/year (similar to deserts [90 g/m2/year] and tundra environments [140 g/m2/year]), whereas swamps, marshes, algal beds and reefs, and tropical rain forests top out at 2,000 or more g/m2/year. Another way to think about this is that the density of food resources is quite scant in the open ocean, except in certain areas where warm and cool currents collide or where upwellings occur, both of which create favorable environments by bringing up nutrients and by extension, attracting fish and other invertebrates— all tasty food resources for hungry seabirds. The trick, though, is locating and capturing these small amounts of available prey in the big blue sea; this understandably requires a complex suite of behaviors as well as experience and knowledge. Thus, it can take years before albatross are strong and experienced enough at sea to return to raise a chick on land. For all we know, Wisdom could have been 10 or 20 when she was originally banded. But, if her age were not surprising enough, Wisdom has furthered amazed her followers by doing what breeding birds do best (or attempt to, in any case). Last year, in 2013, Wisdom successfully raised a chick at Midway Atoll NWR, making her the oldest known breeding bird in the wild. This year, Wisdom surprises us yet again. As we don our binoculars to catch a glimpse of Wisdom, it’s hard to believe that we are staring at the oldest bird in the wild. She looks back at us with deep, black eyes. You might say you can see the ocean in her eyes. Wisdom sits contently in the sunlight, tucking her bill back into the downy feathers of wings for a quick nap in the afternoon. Then, she stands up for a moment to preen herself and as she does so, we see the smooth, cream-colored shape of an egg in her nest. 63 years and counting (and her 7th consecutive year breeding at Midway), Wisdom has laid an egg and is poised to break her own record of the oldest known breeding bird in the wild. We are quiet, careful not to disturb any other albatross, and as we watch Wisdom, we wonder about her life, all that she has seen, all that she knows about the great unknown tracts of the ocean that she has covered for more than 60 years. Wisdom is indeed a fitting name for this remarkable bird and also a reminder of the incredible life history and ecology of these feathered wanderers of the sea. Laysan Albatross are captains of the sky, spending the majority of their lives (nearly 90%) in the air, flying thousands of miles each year in search of food and covering vast tracts of the North Pacific Ocean. In fact, researchers have estimated that Wisdom has flown over 2 million miles since she was first banded in 1956, a distance equivalent to 4 round-trip expeditions to the moon and back. The only time albatross ever leave their realm of the sky is to breed. By the thousands (even hundreds of thousands), Laysan Albatross will return to a handful of islands and atolls (most notably Midway Atoll NWR) to raise their young. Pairs typically bond for life, a rarity among most avifauna but relatively common among seabirds. Interestingly enough, divorce rates among other bird species vary rather drastically, ranging from nearly 100% in House Martins (Delichon urbicum) and Greater Flamingoes (Phoenicopterus roseus) to numbers hovering around 0% among Australian Ravens (Corvus coronoides) and Waved Albatross (Phoebastria irrorata). For humans in the United States, recent divorce rates average between 40%-50%, about the same range as the Masked Booby (Sula dactylatra). Mallards (Anas platyrhynchos) do surprisingly well, and pair bonds are 91% successful; Piping Plovers (Charadrius melodus), on the other hand, have a divorce rate around 67%. But, back to the Albatross. Like other albatross species, the Laysan Albatross also tend to mate for life. And while this particular life history trait is interesting in of itself, the related elaborate courtship displays are probably the most popular and stunning aspect of this species’ breeding ecology. Courtship begins with the arrival of the birds at the breeding grounds; early in the season, dance parties seem to break out around the corner of every Naupaka shrub involving complicated routines accented by sky moo’s, rapid-fire bill claps, and enthusiastic head bobs. Dancing is the most common among juvenile birds and they will continue to boogie and bop the whole breeding season through. In fact, it can take albatross multiple years to find their mate for life and form a pair bond; interestingly enough, older birds that have already paired up dance less or not at all, and maintain their bond in other ways, such as mutual preening. Once paired up, though, these bonds between albatross remain intact until broken by the death or disappearance of a partner. Laysan Albatross may breed as early as age 5, while most breed around 8 to 10 years of age. Even then, several years may pass before an albatross successfully learns how to successfully breed and rear a chick. One year, a pair might only build a nest; the following year, an unviable egg might be laid; perhaps after that, the pair will have a couple of unsuccessful trials with chicks dying before finally figuring it out. The pair may also skip breeding between years in order to engage in other important, energetically-intense activities, like molting. Females lay only one, precious egg per year; if it is destroyed, it is not replaced. Once the egg is laid, the pair will take turns incubating, usually for two-week stints, until the chick hatches in late January to early February. The parents will continue to take turns going out to sea to find food for their ever-hungry chick until it is ready to fledge; at that point, the chick will be on its own and must leave the breeding colony out into uncertain waters. Currently, most of the Black-footed Albatross on Midway Atoll NWR have already laid their eggs, while the Laysan Albatross are usually a week or two later, usually in the first week of December. The first few Laysan Albatross eggs were spotted last week and Wisdom now joins the ranks of the surrounding incubating parents. After laying her egg, Wisdom will stay and incubate it for around 2 days until her mate returns to take over incubation while she leaves for the sea to replenish herself after the energetically intensive effort of egg-laying. We wonder, will Wisdom be able raise another chick this year? Only time will tell and until then, we leave Wisdom in peace between the masses of wandering, waddling Laysan Albatross.
31 Comments
12/12/2014 01:13:46 am
What a wonderful story about Wisdom and the beautiful Laysan Albatross. Incredible she is still incubating eggs and raising young at her age!!! Would love to visit this area one of these days and witness the amazing scene or myself. Thanks for sharing:)
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Yolande
24/12/2014 07:45:29 pm
Prachtig, je kan er een boek over publiceren! Lijkt me toch geen lolletje op mijn leeftijd nog zo'n jong groot te brengen. Maar dat zit in zo'n brein anders in elkaar. Hebben ze Albatrossen al 'ns voorzien van zenders? Dan zou je mogelijk wat meer te weten komen over hun wel en wee op zee.
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