Download (PDF 111 KB): https://research.fs.usda.gov/download/treesearch/31191.pdf
Abstract
Spotted Knapweed (
Centaurea maculosa) seeds were found in the pellets of Great Horned Owls (
Bubo virginianus). That apparently resulted from owls preying upon Deer Mice (
Peromyscus maniculatus) which had incidentally consumed knapweed seeds while foraging for the larvae of biological control agents within knapweed seedheads. Successful germination of 1% of the seeds shows that knapweed seeds recovered from owl pellets can be viable after being ingested by both species and suggest that Great Horned Owls can act as indirect dispersers of Spotted Knapweed seeds.
Citation
Pearson, Dean E.; Ortega, Yvette K. 2001. An indirect dispersal pathway for spotted knapweed seeds via deer mice and great-horned owls. Canadian Field-Naturalist. 115(2): 354.