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Well, we are now six weeks into 2018 and the question still seems to be 
are Black-capped Chickadee numbers down in numbers as they were during 
the Christmas Bird Count?  And a lot of us are looking at our feeders 
and the answer seems to be yes indeed.

So using eBird data for all of Vermont from 2008 to 2018 for the first 
six weeks of the year we can get an overall view, but it is not really 
possible to sort out specifically data from feeders.

I pulled out from eBird the "frequency" and "average count" data for 
each of the first six weeks of the year for those 11 years plus for all 
years combined as far back as they go, averaged them for each year and 
the combined "all years", and compared the years.

"Frequency" is the percent of all eBird checklists submitted during the 
period that had at least one Black-capped Chickadee. This measures notes 
how common or not the species is in the landscapes being birded, 
including feeders reported to eBird. "Average Count" is the average 
numbers of birds reported on the checklists having at least one 
chickadee.  This corresponds with comments such as "there were a lot of 
chickadees in the woods today" or "haven't seen as many chickadees at my 
feeder as I saw last year.

Some results:

The average 'frequencies" for the six week period range from 43% to 64%, 
for the 11 years.

The average "average counts" for the six week period range from 4.7 to 
7.5 birds per checklist.

Ranking the years from highest "frequency of observation" to lowest, 
this year is the 4th highest at 58% of all checklists submitted.  I.e., 
Chickadees are being reported more frequently than in most years.

Ranking the years from highest "average count" to lowest, this year is 
dead last at 4.7 birds per observation.  I.e. the number of Chickadees 
on checklists is the lowest during this time period for any year since 
sometime before 2008.

The data for all years combined for Vermont for these six weeks of the 
year are:    "frequency" of 55%,  three percent lower than this year's 
frequency; and "average count" 6.1, which is substantially higher than 
this year's 4.7.

Compared with the previous two years, this year the birds are being seen 
more often, but significantly fewer in numbers when seen.

Good luck with your Great Backyard Bird Counts!

Ian




On 2/15/2018 6:42 PM, Pamela Coleman wrote:
> None up the road in Mt Tabor either - seems like when the temps soar the birds disappear :-(  Sure hope colder temps bring them back for the GBBC!!
>
>
>        From: Ruth <[log in to unmask]>
>   To: [log in to unmask]
>   Sent: Thursday, February 15, 2018 5:08 PM
>   Subject: [VTBIRD] NO BIRDS! and chickadees
>     
> Unbelievably, I have seen NO birds at my feeders or suet today.  From dawn till I left the house at 9 a.m. - NO BIRDS!  Not a junco in sight. I looked around for predators, but saw none.  Now as dusk approaches... still not a bird at my feeders.  Is this happening any were else today - Thurs.?
>
>
>   I have just read the summary report of this year's CBirdCounts  https://vtecostudies.org/blog/cbc-roundup-the-118th-christmas-bird-count-by-the-numbers/  EVERYONE, reported low numbers of chickadees.  This goes along with fewer birds at feeders during the fall... and who knows what the GBBC will turn up.  Has anyone speculated what has happened to the chickadees?    Die off?  moved south? hiding?  This is very disconcerting to me.
>
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>
> Ruth Stewart
> E. Dorset, VT
>
>