hell tweets,

i have long been interested in the effects of iron on birds,
especially nectivorous birds, because the birds that i have
been breeding (and that i now research!) are the lories --
nectar- and fruit-feeding parrots. All species of lories are
susceptible to excess dietary iron, and some species of lories
are acutely sensitive to "iron storage disease" (also known as
hemochromatosis) -- where excess dietary iron is stored in the
liver, subsequently damaging it, and killing the bird.

perhaps not surprisingly, captive-bred lories are not the only
nectivorous birds that are susceptible to the efffects of
excessive dietary iron, wild-caught hummingbirds are also
susceptible, as revealed in the following report from the
sonora desert museum.

this report is a good cautionary tale for all of us who feed
commercial hummingbird feeds to wild hummers.

(as an aside, people also are susceptible to hemochromatosis,
but that's another story for another day).

regards,

Devorah A. N. Bennu, PhD
email:nyneve at amnh.org or nyneve at myUW.net
work page http://research.amnh.org/ornithology/personnel/bennu.htm
personal pages http://research.amnh.org/users/nyneve/

---------- Forwarded message ----------
No More Excess Iron is Allowed:
AN ARIZONA ZOO PROTECTS ITS HUMMINGBIRDS

Beginning in January 2001 the charming fluttering hummingbirds
began falling dead. Shawnee Riplog-Peterson, ornithology
curator of the Arizona Sonora Desert Museum in Tucson said
"It is not uncommon to lose birds of all ages." The deaths
continued until March 2002. By then the entire hummingbird
population of 20 birds was gone.

What alerted us, say Riplog-Peterson, was that within a 2 week
period we lost 3 birds.

Pathologists at the University of Arizona performed necropsy on
the birds and made a devastating discovery. Iron storage
disease had destroyed the birds. Their livers had absorbed excess
iron, which compromised the immune system, said Peter Siminski,
the museum's collections director.

The nectar fed to the is made of sugar, vitamins, minerals and
protein. Workers tested the commercial formula and found that it
contained 10 times the amount of iron it should have.

While some iron is needed, some of the 3 gram birds had 40 times
the iron level required. Riplog-Peterson said Some things you
have control over and other things not. As long time readers of
Ironic Blood [a newsletter about hemochromatosis, dev] know mynah
birds can be treated with tiny phlebotomies, but you just can't
get blood out of a creature weighing 3 grams.

OTHER ANIMALS:

Leslie N. Johnston DVM has spoken at IOD symposiums about ostriches
that are susceptible to iron overload. Johnston said Birds cannot
tolerate any excess iron.

NEW HUMMINGBIRDS

A new population of hummingbirds has been installed in the remodeled
aviary. We now test every single batch of nectar for iron. Though
the feed manuracturers are notified to cut down on iron, workers are
taking no chances with the precious hummingbirds.

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