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How to measure a live octopus

Nancy

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We were discussing this over on Ceph Care - Jean thought you might know the answer, Steve....(or Kat)

Is the only accurate way to measure a live octopus by the distance between the eyes? If this is so, how do you take this measurement?

I can measure Ollie and get a different answer for arm length and mantle each time I try!

Thanks,

Nancy
 

Steve O'Shea

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Hi Nancy. Probably the only reliable way to do it would be to measure the volume of water little Ollie displaced at any point in time; how to relate that back to 'body mass/weight' I don't know. They are such contortionists that none of arm length, mantle length or inter-ocular distance will give the same measurement twice.
Cheers
O
 

Nancy

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I don't think little Ollie would appreciate being measured by displacing water, so I'll just have to guess how big he is.

I had forgotten about the chart at the end of your excellent article - It seems that Ollie must be a moderate sized octopus now, and that will have to do :smile:

Nancy
 
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pkilian

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@Nancy you might be able to get a semi-accurate measurement of mantle length (which is how I have always measured octo size, from a point midway-between the eyes to the farthest back point of the mantle) If you can take a picture with Ollie and a ruler somewhere in the picture. You can use image editing software like ImageJ (I can send you a link if you would like) to use the ruler to measure Ollies mantle size. You can also do this for things like arm length, sucker cup diameter, etc.
 

tonmo

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@Nancy you might be able to get a semi-accurate measurement of mantle length (which is how I have always measured octo size, from a point midway-between the eyes to the farthest back point of the mantle) If you can take a picture with Ollie and a ruler somewhere in the picture. You can use image editing software like ImageJ (I can send you a link if you would like) to use the ruler to measure Ollies mantle size. You can also do this for things like arm length, sucker cup diameter, etc.
When you look at the date, @pkilian , you'll see Ollie was from back in 2003! (@Danielle Nicole bumped it :biggrin2: ....Great thread -- thanks for updating it with this tip.

@Nancy learned a lot from this experience -- it led to writing a great book with @Colin! :smile:
 

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