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Ocean Birds & Water
Name: Don
Status: N/A
Age: N/A
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Date: N/A
Question:
Sea birds spend a considerable amount of time over the sea
particularly those that migrate. My question is " Where do sea birds get
their freshwater for survival. Can they turn salt water into fresh water?"
Replies:
Truly oceanic birds have specialized salt glands:
"All aquatic sea birds that live in saltwater environments have salt glands,
which enable them to drink seawater and excrete the excess salt. Albatross,
shearwaters, storm petrels, and diving petrels are considered the most
exclusively marine of all sea birds.
http://www.allthesea.com/Sea-Bird.html
Other birds that frequent coast lines, and those that migrate over the ocean,
can find fresh water on land.
J. Elliott
Don
Sea birds have glands in their heads that filter salt out of their blood and
discharge salt out of their nose. It doesn't appear that the kidney's have
a significant role in salt excretion of sea birds.
The following URL reports on an experiment in which a bird is ingested with
134 ml of salt water
And then over a three hour period excretions from the bird's nose and colon
were measured for salt content:
http://books.google.com/books?id=Af7IwQWJoCMC&pg=PA346&lpg=PA346&dq=%22Sea+G
ull%22+Salt+Excretion&source=bl&ots=TYoZUw0qFj&sig=1Sm8JPiu3-FKdw9x6S7H91g3d
uE&hl=en&ei=O0CZStGAKIOd8QazhJW8BQ&sa=X&oi=book_result&ct=result&resnum=6#v=
onepage&q=%22Sea%20Gull%22%20Salt%20Excretion&f=false
I am sure that if the birds have access to fresh water they would prefer
that. But for birds that spend years at sea, like the albatross, they have
this biological capacity to excrete salt from their blood after drinking sea
water.
Here is another URL about the black footed albatross:
http://books.google.com/books?id=Af7IwQWJoCMC&pg=PA346&lpg=PA346&dq=%22Sea+G
ull%22+Salt+Excretion&source=bl&ots=TYoZUw0qFj&sig=1Sm8JPiu3-FKdw9x6S7H91g3d
uE&hl=en&ei=O0CZStGAKIOd8QazhJW8BQ&sa=X&oi=book_result&ct=result&resnum=6#v=
onepage&q=%22Sea%20Gull%22%20Salt%20Excretion&f=false
Aren't you glad you're not the birds in the experiment?
Sincere regards,
Mike Stewart
here is a family of migratory sea birds called "tubenoses" that excrete salt out
of a gland at the base of the bill. An albatross is an example. This is necessary
for the reason you point out; they drink saltwater and excrete the salt out their
"nose". Some penguins also do this, and I have personally seen a penguin "sneezing"
salt crystals out of their "nose" (base of the beak) every few minutes.
Paul B.
Sea birds do drink salt water! The salt is moved through their blood stream and then
excreted in salt glands above their eyes. The salty fluid comes out of their nostrils
and then runs down grooves in their bill. When the drops get larger the bird will shake
its head and return the salt to the ocean.
Grace Fields
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Update: June 2012
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