@misc{indiciae2e97092fe7c8,
  title = {Canvasback food density in the Mississippi River Delta: Habitat and temporal differences},
  author = {Ronald R. Bielefeld and Alan D. Afton},
  year = {1992},
  url = {https://pubs.usgs.gov/publication/70204485},
  note = {Source identifier: 70204485}
}