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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