two such ototlith references are
Panfili and Ximenes 1992. Measurements on ground or sectioned otoliths: possibilities of bias. J off Fish Bio. 41:201-207. and
Grahm and Orth 1987 Otolith aging of yoy smb in R.C. Summerfelt and G.E.Hall edts. The Age and Growth of Fish, Th Iowa StateUniversity Press. Ames,Iowa
I counted daily increments on yoy smallmouth bass. I adapted the grahm and orth method and found that a biosonics video setup made life much easier and the eyes crossed much less.
If you would like details I would be happy to discuss the methods: M. Mccosh 716- 691-5456 or [log in to unmask]
______________________________ Reply Separator _________________________________ Subject: daily growth increments & storms Author: Academic forum on fisheries ecology and related topics <[log in to unmask]> at 9DE~INTR Date: 12/12/96 11:00 AM
One of my graduate students Kathleen McDaniel ([log in to unmask]) is interested in determining whether storm events which produce high flows in a southern Appalachian stream produces detectable changes in the daily growth increments in mottled sculpin (Cottus bairdi). Our hypothesis is that storm events that disturb the substratum will have a negative effect on growth by: 1) reducing prey availability for sculpin (i.e. through mortality orreduced movements of invertebrates), or 2) reduced foraging activity of sculpin, 3) other possibilities exist but we won't bore you with them all. Annuli on sculpin saggitae are easily visible with a dissecting microscope, and other investigators have validated annuli for sculpinin other regions. We haven't found very many references (<5) on the detection of daily growth increments in stream fishes, and are wondering if other investigators are currently engaged in this pursuit (hmm I should be able to list the all the ones we've found, but the papers r at home, there was ben victor's study on fallfish and one on competition between salmonids). Any comments on this thread would be welcome as would references we've missed (send them directly to kathleen's e-mail address and she will then summarize them for the list, god its rough being a grad student these days isn't it). BTW we do have the book edited by D.Secor on Recent Developments in Otolith Research (the S. Carolina Press book). Also we are hoping to find a lab that would be willing to show Kathleen how to prepare the otoliths (we can read them here). We have a total of 400 that need to be prepared and examined. The sagittae range from about 2.5 mm to 5 mm in maximum length, and the maximum age wehave detected is six. One last note, if we should have saved all the lapilli please mail meprivately, cuz you guessed it, they were impossible to find, so we don't have any.
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