satellite view from PMNM
E komo mai; welcome! Midway Atoll National Wildlife Refuge is surrounded by a lei of foam in the middle of the North Pacific; it's a beautiful, special place.

Not only are there albatross on Midway, but many other interesting kinds of wildlife, both on the land and in the sea. Please enjoy exploring FOAM, an educational blog actively done while on Midway from May through August 2010. Posts are added from off-Midway, as information becomes available. If you're interested in a particular topic, please use the search box or the alphabetical list of "labels" along the left side of the blog page.

Thursday, July 22, 2010

Albatross Barf

Before albatross fledglings (the grown-up chicks) leave Midway Atoll National Wildlife Refuge, they have to get rid of any stuff they have in their stomachs that can't be digested.  Their stomachs pack it all together into what's called a "bolus."  Then the bolus gets thrown up and out of the chick's wide-open beak.

Can you see the difference in the neck size between these two Laysan Albatross?  The left-hand albatross is trying to pass up a bolus.  Notice how much wider its neck is; it must be very uncomfortable!

For the first 5 months or so of their lives, albatross chicks are fed food which their parents bring them from the ocean.  Albatross especially like to eat flying fish eggs and squid; yum!  But the squid mouths, called beaks, can't be digested because they're made out of tough material, sort of like a finger nail.  Since flying fish eggs are usually attached to floating objects, the albatross often swallow floating volcanic rocks (called pumice) and sticks. which the fish eggs are attached to.  So, squid beaks, pumice and sticks are natural parts of bolus barf.

But there are also some man-made items in boluses.  This short video shows a Laysan Albatross chick throwing up a bolus, or maybe just part of one.  I think you'll be surprised to see what I found inside this bolus.

Albatross Barf from Barb Mayer on Vimeo.

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