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USGS · 70154958

An artificial perch to help Snail Kites handle an exotic Apple Snail

Kyle E. Pias·Zach C. Welch·Wiley M. Kitchens
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Abstract

In the United States, the Snail Kite ( Rostrhamus sociabilis plumbeus ) is a federally endangered species and restricted to the wetlands of south-central Florida where the current population numbers less than 1,500. The Snail Kite is an extreme dietary specialist, previously feeding almost exclusively on one species of snail, the Florida Apple Snail ( Pomacea paludosa ). Within the past decade, an exotic species of apple snail, the Island Apple Snail ( Pomacea insularum ), has become established on lakes in central Florida. Island Apple Snails are larger than the native Florida Apple Snails, and Snail Kites handle the exotic snails less efficiently. Juvenile Snail Kites, in particular, have lower daily energy balances while feeding on Island Apple Snails. An inexpensive, easy-to-construct platform was developed that would provide Snail Kites with a flat, stable surface on which to extract snails. The platform has the potential to reduce the difficulties Snail Kites experience when handling exotic snails, and may benefit the Snail Kite population as a whole. Initial observations indicate that Snail Kites use the platforms frequently, and snails extracted at the platforms are larger than snails extracted at other perches.

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Kyle E. Pias, Zach C. Welch, Wiley M. Kitchens. 2012. An artificial perch to help Snail Kites handle an exotic Apple Snail. https://doi.org/10.1675/063.035.0217

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