While it’s cold and snowy where you are, it’s a warm
sunny day on the Pacific atoll of Midway Island, where mating season just ended
for the Laysan albatross. Most famous of these large seabirds is Wisdom, the
oldest known wild bird. She’s at least 67 years old and still laying eggs.
Being that old and still raising young makes me wonder just how long these
birds can last.
Wisdom’s age was discovered in 2002 when her band was
replaced. The biologist who replaced her band looked up her number and noticed
that he originally banded her in 1956, and at that time she was an adult of at
least 5 years old.
Wisdom (right) and her mate during nesting season (USFWS) |
What is remarkable about this particular bird so
special, at least to me, is that she managed to survive so many threats in her
time, beyond the normal dangers like predators, disease, and typhoons. Working
in her favor are the Migratory Bird Treaty and the US Wildlife Refuge System,
protecting her and her kind from human predation and habitat loss at their
nesting sites on Midway.
Working against Wisdom and other albatrosses are a
whole host of man-made problems. Foremost among them is ocean plastic. Laysan
albatrosses feed at night, and their food is fish, squid, and fish eggs that
come near the surface. Sadly, floating garbage is also at the surface. In a tragic
sequence of events common to marine life everywhere, they mistake plastic for
food and either eat it themselves or feed it to their chicks. Despite having
full stomachs, the birds and other critters die of starvation because plastic
is not very nutritious.
Invasive species are also beginning to take a toll on
the albatrosses. They have already been extirpated from the Hawaiian Islands,
outcompeted or outright killed by the dogs, cats, pigs, and rats that
accompanied Europeans as they traversed the Pacific. Now, the Midway colony is
under attack by mice. While the birds are much larger than the mice, they
succumb to bite wounds rather move to a mouse-free area because of their
dedication to their eggs. US Fish and Wildlife Service is working on eradicating
mice from Midway, but having lived with them for thousands of years I think we
all know how well that will work out.
Mouse attack victim (Audubon) |
This week's information comes from the US Fish and Wildlife Service and the National Audubon Society
What a wonderful informative article! Thank you so much Josh!
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