Birding/house sparrows

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Expert: - 5/17/2004


Question
We have a pair of house sparrows in a birdhouse outside our window.  The young have recently hatched and the parents are busy hunting and feeding the young.  Twice I have observed one parent come out of the house with something about an inch long that I can only describe as looking like a slug.  It is white on one part, but dark colored on the other side and appears slimy.  My observations were very brief, perhaps 1 or 2 seconds, so this is difficult to describe.  Do you have any ideas as to what this object might have been?  Laurie from Franklin Lakes, NJ

Answer
I know exactly what it is. It is a fecal sac. When the young produce waste products (feces and uric acid) they produce them in a membranous sac. This is so the waste products do not foul the nest. The parents pick these up and dispose of them, keeping the nest clean. For more information on wild birds, go to www.ornithology.com. Roger Lederer

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Roger Lederer

Expertise

Any and all about WILD birds - the science of ornithology. Information about birdwatching, ecology, conservation, migration, behavior, banding, rehabilitation, feeding, songs, binoculars, identification, and careers in ornithology. No questions about pet or caged birds, please.

Experience

Have a PhD and over forty years as a professional ornithologist - research, teaching, author, speaker, webmaster of Ornithology.com . Have written thirty scientific papers, three bird field guides, a textbook in ecology and two recent books entitled "Amazing Birds" and "Birds of New England". Have traveled to over 90 countries watching birds.

Education/Credentials
PhD in Zoology/Ornithology; Emeritus Professor of Biological Sciences; former Dean of the College of Natural Sciences at California State University, Chico

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