Fluctuating asymmetry in Gudgeon
Description : Does anyone have information about fluctuating asymmetry
in fishes, more particularly in the Gudgeon (Gobio gobio)?

I also would like information about the 'DeLury'method. It's
a depletion method, in which one tries to catch as many fishes as possible
In each catch, the fishes are kept apart and are not released
until the end of the last catch. This method leads to a
depletion of the population number, which means that the
number of fishes caught in each catch will decrease. This
makes it possible to make a linear regression between number
of fishes caught in each catch (Y-axis) and accumulated number
of fishes caught in the previous catches (X-axis).
Like this, one can make a population estimate by calculating
the intercept with the X-axis. My question is : When one makes
this estimate, how can he calculate the 95% confidence interval ?
I haven't found any work in which this has been done.
Regards, Alain

By : Dillen Alain
Date/time : 22/12/1999 04:14:00
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Post no.
Date/Time : 5/1/2000 08:37:00
Daniel Pauly
No email
Concerning the De Lury method: I think the reason why a method for computing confidence intervals missing is that unexploited population size is estimated as a ratio (intercept on the x-axis), and there are no good parametric methods for estimating the confidence interval of ratios. Moreover, the points of the linear regression are not independent at all .
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