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Life Sciences Commons

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Retrospective Theses and Dissertations

Environmental Sciences

1994

Ecology and evolutionary biology

Articles 1 - 2 of 2

Full-Text Articles in Life Sciences

Structure Of Breeding-Bird Communities On Natural And Restored Iowa Wetlands, Julie Ann Schreiber Jan 1994

Structure Of Breeding-Bird Communities On Natural And Restored Iowa Wetlands, Julie Ann Schreiber

Retrospective Theses and Dissertations

No abstract provided.


Evaluation Of Factors Influencing Grit Use By Birds , James Paul Gionfriddo Jan 1994

Evaluation Of Factors Influencing Grit Use By Birds , James Paul Gionfriddo

Retrospective Theses and Dissertations

Avian grit use was investigated by examining the gizzard contents of free-ranging birds and by conducting aviary experiments with captive birds. Free-ranging Iowa House Sparrows (Passer domesticus) were captured, and their gizzard grit was compared by sex, season, and diet. Males and females did not differ in mean grit amounts (overall x = 580 particles) or sizes, (overall x = 0.5 mm). Birds captured during March and August contained more grit than birds captured during September through February (x = 674 vs. 477). Gizzards containing >75% animal material (insects) had more grit than those containing, >75% plant food (x = 681 vs. 531 ...