The Influence of Different Cover Types on American Robin Nest Success in Organic Agroecosystems

There are many opportunities for biodiversity conservation in organic farm systems. Successful and sustainable conservation efforts in organic systems, however, need to measure appropriate outcomes. In particular, data are needed on the breeding success of associated wildlife species. We measured nesting success of the American Robin (Turdus migratorius) in woodlands embedded within eight organic farms in eastern Nebraska. We modeled daily nest survival rate to identify land use and land cover patterns that optimize conservation of birds in organic farm systems. The percentage of a crop in the fields adjacent to linear woodlands best predicted daily survival rate. Daily survival rate was lower in fields adjacent to wheat and greater in woodlands adjacent to soybean fields, though the latter may be a weak effect. There was no evidence that reducing the area allocated to organic crop production would improve daily survival rate but rather an evidence of a patch-matrix interaction. These results suggest that, if suitable nesting sites exist, organic farmers can complement local conservation efforts without losing working farmland