Size and mass of grit in gizzards of sandhill cranes, tundra swans, and mute swans

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Because it has been suggested that waterbirds may ingest lost or discarded lead fishing weights as grit, we examined grit in the gizzards of Sandhill Cranes (Grus canadensis), Tundra Swans (Cygnus columbianus), and Mute Swans (Cygnus olor), three species where individuals have been poisoned by the ingestion of lead fishing weights. The greatest proportion (by mass) of grit in gizzards of Sandhill Cranes consisted of particles with a minimum dimension of 2.36-4.75 mm. Grit particles in swans were much smaller, with the most prevalent (by mass) being 0.6-1.18 mm. The greatest dimension of the largest grit particle found in cranes and swans was 17.4 mm and 14.0 mm, respectively. The U.S. Environmental Protection Agency has proposed a ban on lead fishing weights of ≤25.4 mm in any dimension. Based on the size of grit particles that we found in gizzards of Sandhill Cranes, Mute Swans, and Tundra Swans, we believe it is unlikely that individuals of those species would ingest, as grit, lead fishing weights larger than 25.4 mm in any dimension.

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Publication type Article
Publication Subtype Journal Article
Title Size and mass of grit in gizzards of sandhill cranes, tundra swans, and mute swans
Series title Waterbirds
DOI 10.2307/1522036
Volume 24
Issue 2
Year Published 2001
Language English
Publisher Waterbird Society
Contributing office(s) National Wildlife Health Center
Description 3 p.
First page 242
Last page 244
Country United States
State Arizona, Maryland, Nebraska, New Mexico, Utah
Online Only (Y/N) N
Additional Online Files (Y/N) N
Google Analytic Metrics Metrics page
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