The Old Fort

Grazing and Nesting

A grant issued by National Geographic and the National Fish and Wildlife Foundation funds four to five FLC students to help Dr. Catherine Ortega  investigate the effects of different cattle grazing regimes on nesting birds.

An abstract of the grant reads:

"Livestock grazing is ubiquitous throughout western North America, and managers of public and private lands are actively seeking management recommendations that will enhance songbird populations.  Previous studies showed that predation and Brown-headed Cowbird parasitism, which have been identified as major sources of nesting failure, may be influenced by livestock grazing.  In southwestern Colorado, where cattle grazing is nearly continuous, realistic grazing options that will minimize possible negative effects for nesting birds need to be identified within the framework of cattle grazing as a dominant  land use.  This study focuses on investigation of the effects of three grazing options (ungrazed during nesting season, low grazing, and moderate grazing) in two habitats (Gambrel Oak and riparian)."

Dr. Ortega reports that in the summer of 1998, they have located over 200 nests of 23 different species on the "old fort".