How large is the world's largest fish? Measuring whale sharks Rhincodon typus with laser photogrammetry.

  title={How large is the world's largest fish? Measuring whale sharks Rhincodon typus with laser photogrammetry.},
  author={Christoph A Rohner and Anthony J. Richardson and A D Marshall and Scarla J. Weeks and Simon J. Pierce},
  journal={Journal of fish biology},
  volume={78 1},
Laser photogrammetry was found to be a promising new cost-effective technique for measuring free-swimming whale sharks Rhincodon typus. Photogrammetric measurements were more precise than visual size estimates by experienced researchers, with results from the two methods differing by 9· 8 ± 1· 1% (mean ±s.e.). A new metric of total length and the length between the fifth gill and first dorsal fin (r² = 0· 93) is proposed to facilitate easy, accurate length measurements of whale sharks in the… 

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