Hi Haans, I don't know how helpful this will be to you, but over the weekend Beth and I were in the area of the Allegheny National Forest in PA. Hiking near Tionesta Creek we had quite a few Ovenbirds calling, and a couple near East Hickory Creek. Best, Steve On 5/29/12 11:26 AM, "Haans Petruschke" <[log in to unmask]> wrote: > Hi, > > In 2001 I participated in a breeding bird survey of the natural areas of > the Holden Arboretum conducted by Carol Skinner: > > https://kb.osu.edu/dspace/bitstream/handle/1811/23979/V103N4_098.pdf;jsessioni > d=352A4364F679C6670B2332DBAC855275?sequence=1 > > > In that study we found Ovenbirds in good numbers on all wooded properties. > > Since 2007 I have been conducting ongoing breeding bird surveys or the same > areas. The protocol we use is different. We use the OBBA2 upgrade protocol > and no set transects, instead tracking our variable routes via GPS. > Additionally we only survey on weekends where as the Skinner study was > conducted every day of the week, and because of the weekday runs, we would > start far earlier than we do now, usually at 0500 or 0530 as opposed to > 0600 or 0630 now. > > We do not find Ovenbirds in the numbers we did in 2001. In 26 runs during > May, June and July of 2011 we found Ovenbird only 3 times, compared to 15 > times during the same time frame in 2001. I wonder how much of this > difference is due to less coverage and later starts and how much is due to > actual declines in Ovenbird populations on these properties? > > European earthworms have devastated the leaf litter and herbacious layers > in some areas of Holden's forests but most areas are very healthy. > Holden's forests tend to be large and unfragmented ranging from a few > hundred acres to over 1000 acres in 2 areas. > > I have sort of noticed this lack of Ovenbirds but did not realize how > dramatic it was until was prompted to look at my field notes by David > Brinkman's comments. This now has me wondering if there is cause for > concern and if we should be looking for Ovenbirds more carefully. Because > the OBBA2 data is qualitative and not quantitative It does not help to > answer this question, and because of the changes in protocol from the first > OBBA it is difficult to draw conclusions over the 2 decades between the > studies. > > Haans Petruschke > Kirtland > > ______________________________________________________________________ > > Ohio-birds mailing list, a service of the Ohio Ornithological Society. > Our thanks to Miami University for hosting this mailing list. > Additional discussions can be found in our forums, at > www.ohiobirds.org/forum/. > > You can join or leave the list, or change your options, at: > http://listserv.muohio.edu/scripts/wa.exe?LIST=OHIO-BIRDS > Send questions or comments about the list to: [log in to unmask] -------------------------------------------- Steve Cagan, photographer [log in to unmask] € www.stevecagan.com www.pbase.com/stevecagan € www.stevecagan.blogspot.com 216-932-2753 (USA) ______________________________________________________________________ Ohio-birds mailing list, a service of the Ohio Ornithological Society. Our thanks to Miami University for hosting this mailing list. Additional discussions can be found in our forums, at www.ohiobirds.org/forum/. You can join or leave the list, or change your options, at: http://listserv.muohio.edu/scripts/wa.exe?LIST=OHIO-BIRDS Send questions or comments about the list to: [log in to unmask]