16 March 2011


(Laysan albatross Wisdom, seen here with her chick at Midway Atoll, March 2011, before the tsunami. Credit: John Klavitter/U. S. Fish and Wildlife Service, via Wikimedia Commons.)

I've tweeted a few times of late about the remarkable Laysan albatross named Wisdom. She's at least 60 years old—the oldest-known wild bird in the US. 

A few months ago she returned to Midway Atoll in the northwestern Hawaiian Archipelago, found her mate, laid an egg, and recently hatched a chick. 

Now the Honolulu Star-Advertiser reports that tsunami waves from Japan's massive quake devastated Midway's seabird breeding rookeries, completely washing over one of the islands and partially submerging the other two. Tens of thousands of albatrosses died, adults and chicks. 

(Calculated wave height of the 2011 tsunami originating near Sendai, Japan.  Credit: NOAA.)

If you click on the image above you'll see the larger version, with the main Hawaiian Islands located in the center-right. The Hawaiian Archipelago tracks west-northwest from there, with Midway just visible near the far end of the island chain, embedded in the high-wave tsunami zone marked in red.

The albatross chicks on Midway were killed by the waves because none have fledged this early in the season. Laysan albatrosses have extremely long dependency periods—64 days of incubation, followed by 165 flightless days before they fledge and leave the island.

(Laysan albatross chicks with a few embedded adults, Midway Atoll. Credit: Mass Communication Specialist 2nd Class Mark Logico, US Navy, via Wikimedia Commons.) 

The adults were likely killed because they don't readily abandon their young.

Plus these are big birds of the open ocean. It takes them a long time to lumber across the water or the beach to get airborne. Midway's old runways turn out to be extremely useful for this purpose.

In the absence of wind, they can't takeoff or land. The Birds of North America Online describes their flight like this:

Depending on wind strength, take-off may be difficult, requiring a long run with the head outstretched, the bird flapping its wings and literally running. Take off from water is similar, requiring furious paddling with the webbed feet. Landings can be equally difficult, especially in birds that have been at sea for months, or in light winds. In the absence of the braking effort of a strong wind, landing birds may occasionally tumble on landing.

Midway is home to about 450,000 of the world's 590,926 breeding pairs of Laysan albatross. The IUCN Red List deems the species Near Threatened.

Some 25,300 black-footed albatrosses also live on Midway Atoll and presumably took some tsunami losses too.

(Black-footed albatross, Midway Atoll. Credit: Forest & Kim Starr, via Wikimedia Commons.)

Plus one pair of short-tailed albatrosses arrived this year. This species breeds on islands off Japan and China and is deemed Vulnerable by the IUCN Red List—with a total global population of only 2,364 individuals. 

A few months ago I tweeted the exciting news that this pair had appeared on Midway—an encouraging sign the species' range might be expanding.

Now, in the wake of the tsunami waves, US Fish and Wildlife officials have found one short-tailed albatross chick, returned it to a nesting area, and installed a remote-controlled camera to monitor it. But they haven't found the parents. 

(Short-tailed albatross. Credit: US Fish and Wildlife Service, via Wikimedia Commons.)

No word yet that I've heard on Wisdom's fate. This late in the breeding season few if any birds will try to lay another egg and start the long cycle again.
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