Hi Matt, >From what you described it would be a little tough, but it sounds like a Bicknell's Thrush, peak is a bit low. Without seeing it, based on the peak I would not put it as a positive ID. They generally always start around 3.5 to 4kHz and peak about 5.5 -6kHz, and have a longer less descending trail/tail in their typical call. In our recordings Gray-cheeked almost never get above 4kHz (+/- 0.1kHz) in their peak and the "tail" drops faster. The length of the tail is sometimes longer in Bicknell's, but that is very variable, I think more so than the frequency variation. Generally, the rule of thumb is if it stays between 3-4kHz its a Gray-cheeked, if its totally above 4Khz peaking around 5.5 to 6kHz its a Bicknell's. Where is your recording station located in WV, in Summit Point? Generally, the closer to the coast the more you'll get, but we do get many here. In 04 I think we had many more for some reason. I would expect you to have them there (possibly more than us) as you are a bit east of us.
Best, Mike Michael Lanzone Biotechnology and Biomonitoring Lab Supervisor Carnegie Museum of Natural History Powdermill Avian Research Center 1847 Route 381 Rector, PA 15677 724.593.5521 Office [email protected] On Thu, Aug 27, 2009 at 4:12 PM, Matt Orsie <[email protected]> wrote: > Hello All, > I was curious as to what you've seen as frequency ranges between > these two species? I've recorded nocturnal calls more off than on since > 2003 and have only seen one or two of what I've called Gray-cheeked > Thrush peak out over 4khz during that time. Most peak out around 4khz > and taper off between 3-3.5khz within 75ms or so. > > I do have one recording that tops off at 4.6khz and takes over 100ms to > wind down. I've wondered for a few years if this could possibly have been > a Bicknell's. > > I know there is overlap but I was still curious to what you have seen as > extremes or averages in your recordings? > > Thanks, > Matt Orsie > Summit Point, WV > > -- > NFC-L List Info: > http://www.NortheastBirding.com/NFC_WELCOME > http://www.NortheastBirding.com/NFC_RULES > > http://www.mail-archive.com/[email protected]/maillist.html > -- > -- NFC-L List Info: http://www.NortheastBirding.com/NFC_WELCOME http://www.NortheastBirding.com/NFC_RULES http://www.mail-archive.com/[email protected]/maillist.html --
