Use of a gel documentation system to measure feather growth bars

  title={Use of a gel documentation system to measure feather growth bars},
  author={Matthew D. Shawkey and Michelle L. Beck and Geoffrey E. Hill},
Abstract Feather growth bar widths have become a standard index of nutritional condition in ornithological research. Traditional techniques of measuring these bars are difficult and slow because the bars are often hard to see. We present a fast and repeatable method of visualizing and measuring growth bars using a gel documentation system from Alpha-Innotech Corporation. This system takes digital photos of objects in a low light chamber. These photos can then be enhanced and measured on a… Expand
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Plumage colour signals nutritional condition in the house finch
  • G. Hill, R. Montgomerie
  • Biology
  • Proceedings of the Royal Society of London. Series B: Biological Sciences
  • 1994
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