An estimated 75 million blackbirds migrate through the sunflower growing regions of the Great Plains and can cause severe damage to ripening sunflower and corn. If bird damage can be reduced or kept at levels <10% significant profits can be made. USDA Wildlife Services (WS) has developed some tools to help producers defend their fields against blackbird damage.
Eliminating problem roosts by applying glyphosate herbicide to dense stands of cattail in wetlands favored by blackbirds has been used successfully and has been a well received program. However, WS only has sufficient funds to treat <1 % of the estimated 547,000 acres of cattails in North Dakota.
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