<?xml version='1.0' encoding='utf-8'?>
<oai_dc:dc xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd">
  <dc:contributor>E.K. Bollinger</dc:contributor>
  <dc:contributor>Douglas H. Johnson</dc:contributor>
  <dc:creator>D.M. Scheiman</dc:creator>
  <dc:date>2003</dc:date>
  <dc:description>&lt;p&gt;Grassland&lt;span&gt;&amp;nbsp;&lt;/span&gt;bird&lt;span&gt;&amp;nbsp;populations are declining. Invasive plant species may be contributing to these declines by altering habitat quality. However, the&amp;nbsp;&lt;/span&gt;effects&lt;span&gt;&amp;nbsp;of invasive plants on&amp;nbsp;&lt;/span&gt;grassland&lt;span&gt;&amp;nbsp;&lt;/span&gt;birds&lt;span&gt;&amp;nbsp;are largely unknown.&amp;nbsp;&lt;/span&gt;Leafy&lt;span&gt;&amp;nbsp;&lt;/span&gt;spurge&lt;span&gt;&amp;nbsp;(Euphorbia esula) is an exotic, invasive weed in the northern Great Plains. We examined the&amp;nbsp;&lt;/span&gt;effects&lt;span&gt;&amp;nbsp;of&amp;nbsp;&lt;/span&gt;leafy&lt;span&gt;&amp;nbsp;&lt;/span&gt;spurge&lt;span&gt;&amp;nbsp;&lt;/span&gt;infestation&lt;span&gt;&amp;nbsp;on densities of breeding&amp;nbsp;&lt;/span&gt;birds&lt;span&gt;, nest-site selection, and nest success in grasslands on the Sheyenne National&amp;nbsp;&lt;/span&gt;Grassland&lt;span&gt;&amp;nbsp;(SNG), North Dakota, USA, 1999-2000. We categorized&amp;nbsp;&lt;/span&gt;spurge&lt;span&gt;-infested grasslands into 3 groups (low, medium, high), based on the area covered by&amp;nbsp;&lt;/span&gt;spurge&lt;span&gt;&amp;nbsp;patches. We surveyed 75 100-m-radius circular points (25 in each group), and searched for nests in 6 16-ha plots (2 in each group). Grasshopper sparrow (Ammodramus savannarum) and savannah sparrow (Passerculus sandwichensis) densities were lower on high-&lt;/span&gt;spurge&lt;span&gt;&amp;nbsp;points than on low- and medium-&lt;/span&gt;spurge&lt;span&gt;&amp;nbsp;points. Bobolink (Dolichonyx oryzivorus) and western meadowlark (Sturnella neglecta) densities were not significantly different among&amp;nbsp;&lt;/span&gt;spurge&lt;span&gt;&amp;nbsp;cover groups.&amp;nbsp;&lt;/span&gt;Spurge&lt;span&gt;&amp;nbsp;cover did not appear to be an important factor in nest-site selection. However, western meadowlark nest success was positively associated with&amp;nbsp;&lt;/span&gt;spurge&lt;span&gt;&amp;nbsp;cover. Vegetation structure is an important indicator of habitat quality and resource availability for&amp;nbsp;&lt;/span&gt;grassland&lt;span&gt;&amp;nbsp;&lt;/span&gt;birds&lt;span&gt;. Changes in vegetation structure caused by introduced plant species, such as&amp;nbsp;&lt;/span&gt;spurge&lt;span&gt;, can alter resource availability and hence affect&amp;nbsp;&lt;/span&gt;bird&lt;span&gt;&amp;nbsp;community composition. Managers of&amp;nbsp;&lt;/span&gt;spurge&lt;span&gt;-infested grasslands should continue current&amp;nbsp;&lt;/span&gt;spurge&lt;span&gt;&amp;nbsp;control measures to help prevent further declines in&amp;nbsp;&lt;/span&gt;grassland&lt;span&gt;&amp;nbsp;habitat quality and&amp;nbsp;&lt;/span&gt;grassland&lt;span&gt;&amp;nbsp;&lt;/span&gt;bird&lt;span&gt;&amp;nbsp;populations.&lt;/span&gt;&lt;/p&gt;</dc:description>
  <dc:format>application/pdf</dc:format>
  <dc:identifier>10.2307/3803067</dc:identifier>
  <dc:language>en</dc:language>
  <dc:publisher>Wildlife Society</dc:publisher>
  <dc:title>Effects of leafy spurge infestation on grassland birds</dc:title>
  <dc:type>article</dc:type>
</oai_dc:dc>