There's a change in the air out at Midway Atoll NWR. The winds have started to pick up, bringing down cool breezes from the north, and -- with the wind-- the once calm, turquoise waters now churn wildly all through the lagoon, accented by white crests and caps. The sky is equally dramatic; clouds bound by, building, swirling, and short showers frequent the atoll. Sweet alyssum (Lobularia maritima) has gone into bloom, covering the ground with a blanket of fine white flowers, almost like snow. Winter is settling in. As the season transitions, going from endless sun to relentless wind, other changes are afoot-- quite literally. For the last two months, Laysan (Phoebastria immutabilis) and Black-footed (Phoebastria nigripes) Albatross have quietly, patiently incubated their precious eggs, carefully perched atop their soft, webbed feet and surrounded by a cozy cove of down feathers. Now, if you listen carefully, in between the rare gaps of howling wind, you might hear a series of soft "peeps" -- the beloved sounds marking the very cusp of nestling season. The process of hatching for albatross occurs over several days. The initial event, in what is endearingly called the "pipping period," occurs when the albatross embryo's beak penetrates the aircell (internal pipping), thereby allowing the embryo to use its lungs to rebreathe the air in the aircell and also to vocalize (“peep”). This event starts around four and a half days before the actual "hatching." Two days later, external pipping begins to unfold, the phase of hatching of which we are probably the most familiar with among any species of bird. During this stage, a star fracture of the shell occurs followed by the creation of a pip hole in the shell. This pip hole is the embryo's first experience with the outside world, its first breath of fresh air beyond the egg, its first glimpse of real, warm sunlight. Hatching, though, is by no means an easy feat; breaking through the eggshell is tiring work and this period, between embryo and nestling, is marked by peak oxygen consumption and respiratory frequency. Moreover, hatching is something that is done completely alone and unaided; parent albatross watch eagerly (sometimes helplessly) from the outside, seemingly offering words of encouragement with high-pitched sighs and squeals, hopefully motivating their offspring to keep going, keep kicking, and keep chipping away at that shell around them. As I walk though one of our albatross reproductive success plots, carefully weaving between Black-footed Albatross nests with snappy parents and avoiding a maze of Bonin Petrel (Pterodroma hypoleuca) burrows, I am reminded by a basic but endlessly fascinating fact: I am in the middle of a seabird colony. As if that were not amazing enough in of itself, being here on Midway Atoll NWR among hundreds of thousands of albatross during this special time of the year, during that dramatic transition from parents patiently incubating eggs to peeping downy chicks popping out, is all the more extraordinary. You can almost feel the excitement amid the albatross; sometimes, if you are lucky enough, an albatross might stand up as its chick is hatching. They might let out intermittent, quiet squeals and carefully, gently touch the bill of their little one. Once out of the shell, the parent stares at the fragile, fluffy chick in between its huge, webbed feet, almost incredulously, as if thinking, "Did that just happen? Is this really my chick? Is everything there- two eyes, two feet, two wings?" It is an incredibly precious experience to be a part of, to see an albatross chick greet the wide, open world. After the two-month incubation period, life will start to change quickly out here. In a couple of weeks, all of the Laysan and Black-footed Albatross eggs will have hatched and the quiet colony will turn into a place of peeping chicks. Although the chicks seem quite fragile at first, they grow quickly. For the first few days after hatching, the chick will remain safe and snug under the brood patch of its parent; after that, the chick will start to peak out at the world beyond the nest cup. If you walk by an albatross nest, you might find yourself doing a double take; a small pair of eyes surrounded by down feathers poking out from the parent albatross' wing, breast, or tail might be watching you! Along with growing curiosity, the chicks will have a growing appetite as well. Because of the unique life history and ecology of albatross (far-ranging foragers of the sea), feeding nestlings is a big job for parents. No food resources for chicks exist on Midway Atoll NWR; instead, parents must fly out hundreds of miles to find upwellings or convergences of currents where sea life abounds, such as squid (especially Ommastrephidae) and flying fish (Exocoetidae) eggs (often attached to pieces of pumice). Adapted to these extreme measures for obtaining food, albatross have evolved a unique digestive system with a proventriculus that acts as a separatory funnel to drain aqueous portions of food, leaving lipid-rich stomach oil for efficient storage and transport of resources. This oily, energy-packed substance is what albatross nestlings will subsist on during their stay at Midway. In fact, albatross nestlings are fed stomach oil exclusively; it also forms the majority of older nestlings' diets. While regurgitated stomach oil week after week may not sound especially appetizing, this is the only food that albatross chicks will receive before they fledge in mid-June to early August and must fend for themselves in the big, blue ocean. Fledging, though, is still months away. Until then, we welcome the thousands of newly-hatched Laysan and Black-footed Albatross nestlings to the seabird colony at Midway Atoll NWR. We wish you warm cover under your parents when the winds blow and rains pound down; we wish you many meals, captured from the sea far from here; we wish you cool shade under native Naupaka shrubs when the sun beats down during the summer and an uplifting breeze to help you spread your wings and fly to your new home that is the ocean. And maybe, hopefully, some day you'll come back to Midway to find a mate, a nest-site, and a life of your own. For a video of the tender and gentle interactions between a parent and nestling Laysan Albatross, be sure to watch my video below or check it out here.
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About MeWieteke Holthuijzen: budding environmental scientist, passionate birder. Archives
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