Re: [cayugabirds-l] Swan count for CBC

[Kenneth Victor Rosenberg]

I will just add to Bill's assessment that, try as we might, the Christmas Bird 
Count "protocol" (= count everything you can count) is a very crude instrument 
for monitoring bird populations and it is probably not worth worrying too much 
about fine tuning most of the counts. That said, avoiding obvious 
double-counting is standard procedure on most CBCs, and Bill is correct that we 
have always strived to determine the most accurate totals for waterfowl, gulls, 
etc, as well as large soaring birds such as eagles and vultures (even the 
flocks of crows coming in to roost).

Beyond that, I have participated in many different CBCs around the country (and 
in the tropics) and have been compiler of at least 6 CBCs, and I can say that 
there is tremendous variation in strategies used to get numbers of species and 
counts of individual species. Most CBCs do put more of an emphasis on species 
totals, focusing on covering representative habitats, finding rare birds, and 
not going much beyond "representative" counts of common birds. Other CBCs 
employ more of a "blitz" strategy to go after national high counts for targeted 
species. Some counts (like ours) make liberal use of owl tapes and other lures; 
other CBCs discourage these – in my experience this variable alone probably 
accounts for more variation in counts of common birds than any other aspect of 
effort or coverage.

The beauty of the CBC though is that there are so many of them that have been 
running for so many years. The real scientific value is in identification of 
broad patterns across large geographic areas over long time periods. For 
example, as Kevin kept pointing out during the compilation, when the Ithaca CBC 
had large numbers of woodpeckers in recent years, so did every other count in 
NY and across the Northeast. Similarly big years for finches are easily 
detected, the declines in species such as kestrels and pheasants, increases in 
wintering Turkey Vultures and many other species, cycles in Wild Turkey 
numbers, etc. are all very apparent in the CBC data, even if each individual 
CBC count is very "fuzzy."

So, while it is tempting to want to fine-tune our local counting to track very 
local populations, the CBC is probably not the best tool for that.

But it's all fun!

KEN


Ken Rosenberg
Conservation Science Program
Cornell Lab of Ornithology
607-254-2412
607-342-4594 (cell)
k...@cornell.edu

On Jan 4, 2013, at 2:48 PM, Bill Evans wrote:

Jody,

The concept of avoiding double counting is implied in the nature of the CBC, 
and there is a spectrum in the level of attentiveness in avoiding double 
counting for different species, different locations, and by different birding 
parties. The key idea amidst all the variables, as you note, is maintaining the 
utility of the data for long-term interpretation of changes, and this involves 
consistency of monitoring (even if it is rough around the edges). Of course 
there is no realistic means for preventing double-counting of chickadees in a 
neighborhood with multiple feeders, but every year there is a concerted effort 
not to double count waterfowl at Stewart Park -- the highest tallies are 
typically taken instead of adding each observer’s sightings, or as I recall, 
one person is designated to count geese, gulls etc. on the lake.

Swans have only been documented on (I believe) 6 Ithaca CBCs in the past 100+ 
years, all in the last two decades. Whatever count total is used, this year is 
our record high count. I don’t recall any years like this one when we had 
multiple flocks in passage, so the previous count totals were likely highly 
accurate and not subject to being double-counted.  However, the evidence 
suggests that a section-added count of ~400 is a 100% overestimate. Using the 
section-added total would likely be a gross deviation from the status quo with 
regard to the accuracy of past swan counts on our CBC. Like the coordinated 
effort at Stewart Park to prevent multiple waterfowl counts, the swan tally 
could be corrected with a bit of coordination in observations this year and 
foresight in future years (i.e., noting flock size, location, trajectory, and 
time).

So, while I generally agree with the importance of maintaining the status quo 
in counting procedures, I don’t agree with projecting the status quo of a 
section-added count (i.e., for chickadees) on swans.

Asher, section counts would not be denied their birds. As one can see from the 
map, section counts in fact help ascertain the accuracy of the migration tally.

Bill E

The evidence suggests some flocks were double and even triple counted, but as 
Ken pointed out there are still some things that don’t add up. Two pieces of 
information that would he
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Re: [cayugabirds-l] Swan count for CBC

[Bill Evans]

Jody,

The concept of avoiding double counting is implied in the nature of the CBC, 
and there is a spectrum in the level of attentiveness in avoiding double 
counting for different species, different locations, and by different birding 
parties. The key idea amidst all the variables, as you note, is maintaining the 
utility of the data for long-term interpretation of changes, and this involves 
consistency of monitoring (even if it is rough around the edges). Of course 
there is no realistic means for preventing double-counting of chickadees in a 
neighborhood with multiple feeders, but every year there is a concerted effort 
not to double count waterfowl at Stewart Park -- the highest tallies are 
typically taken instead of adding each observer’s sightings, or as I recall, 
one person is designated to count geese, gulls etc. on the lake.

Swans have only been documented on (I believe) 6 Ithaca CBCs in the past 100+ 
years, all in the last two decades. Whatever count total is used, this year is 
our record high count. I don’t recall any years like this one when we had 
multiple flocks in passage, so the previous count totals were likely highly 
accurate and not subject to being double-counted.  However, the evidence 
suggests that a section-added count of ~400 is a 100% overestimate. Using the 
section-added total would likely be a gross deviation from the status quo with 
regard to the accuracy of past swan counts on our CBC. Like the coordinated 
effort at Stewart Park to prevent multiple waterfowl counts, the swan tally 
could be corrected with a bit of coordination in observations this year and 
foresight in future years (i.e., noting flock size, location, trajectory, and 
time).

So, while I generally agree with the importance of maintaining the status quo 
in counting procedures, I don’t agree with projecting the status quo of a 
section-added count (i.e., for chickadees) on swans.

Asher, section counts would not be denied their birds. As one can see from the 
map, section counts in fact help ascertain the accuracy of the migration tally.

Bill E

The evidence suggests some flocks were double and even triple counted, but as 
Ken pointed out there are still some things that don’t add up. Two pieces of 
information that would he
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Re: [cayugabirds-l] Swan count for CBC

[Asher Hockett]

Thanks, Jody, for a really excellent post!

Birds have a bad habit of flying! This leads to their having a propensity
for being in two or more places nearly at once. Behind the old NCR building
on 96B, we flushed a Red-tail. A few minutes later we saw another gliding
overhead in the opposite direction. A few minutes after that there was one
flying back and forth over the trees to the south. We surmised it was the
same bird and only counted/reported the one.

In the same spot, at one end of the parking lot we observed 2 Yellow-rumps.
Later, a hundred yards to the north, we observed another. I may
(likely) have been one of the first two, but I thought it looked like a
third and counted it that way. All 3 responded to the chickadee/screech owl
mobbing call recording, so certainly there is a good chance that one of the
earlier Y-rs flew to the new area to see what was going on.

The counters ultimately make choices about how many of what they are
seeing, and the factors which dictate these choices seem to me to be as
variable (and ephemeral) as those which determine which flock of Tundras
was seen and how many times.

And since some of those swans were counted in area VI, why wouldn't I, as
area coordinator, want to have them in the sector total? I mean, it kind of
beats sitting there at the lab during the compilation and saying NONE to
every other species enumerated! Yes, I know that NONE is totally valid
data, but still, we are not machines, we are human beings. (and we want
birds!)
Asher
On Fri, Jan 4, 2013 at 11:37 AM, Jody W Enck  wrote:

>  This discussion has been interesting to “watch” as it has unfolded.  I
> certainly understand the desire folks have to make the counts as accurate
> as possible.  Still, I wonder how all this adjusting of the numbers
> after-the-fact for just one species, and for just one year, influences the
> utility of the data for comparative purposes from year to year.  Given the
> year-to-year variability of the weather and its uncertain influence on both
> long-distance migration (e.g., of swans) and local movements (from and to
> feeders), I wonder if it simply makes the most sense to keep doing things
> the way they always have been done -- recognizing and even accepting that
> various species will be more or less likely to be affected in any given
> year with respect to whether they are double or triple counted, or
> undercounted.
>
> If the purpose of the count (at least one of the major purposes) is to be
> able to examine long-term trends, then it seems that consistency of
> methodology from year-to-year should trump our noble attempts to improve
> within-year accuracy.
>
> How far do Chickadees and other feeder birds move around on cold, blustery
> days like we had on January 1st?  The 6 feeder watchers in my neighborhood
> probably all had the same individual birds visit their feeders.  Seems
> rather endless to try to figure out how to deal with all the uncertainty in
> the data collection.  I know the inquisitive scientist within me loves the
> challenge of trying to reduce that uncertainty, but a reduction in this
> kind of uncertainty probably will not enhance the utility of the data for
> its intended purpose.  Besides, the discoverer within me loves being out in
> horrible conditions just seeing what I can find, recognize, and learn.  I
> suppose it’s probably the same - to a lesser or greater degree- for
> everyone who looked for birds on the First.
>
> Have fun,
> Jody
>
> Jody W. Enck, PhD
> Human Dimensions of Natural Resources
> Cornell Lab of Ornithology
>
>  *From:* Bill Evans
> *Sent:* January 4, 2013 10:05 AM
> *To:* CAYUGABIRDS-L
> *Subject:* Re:[cayugabirds-l] Swan count for CBC
>
>   Last night I made of a Google map of the swan flock information
> reported to the listserv. I updated the trajectories and markers this
> morning adding some deductive/speculative text.
>  Cayuga Bird Club 2013 CBC Swan flock 
> map<http://maps.google.com/maps/ms?ie=UTF&msa=0&msid=208086491899212349523.0004d26dc6966e4c7c382>(click
>  markers to read text – if you have a Google acct and log in you can
> add information to the map)
>
>  The evidence suggests some flocks were double and even triple counted,
> but as Ken pointed out there are still some things that don’t add up. Two
> pieces of information that would help complete the picture would be more
> description on the location and trajectory of the flock of 21 (@ ~2:45pm)
> seen by Marty’s group. I don’t have that flock on the map and it doesn’t
> seem like it could have been the same flock of 19 I had at 2:15 or Ken had
> at 2PM, which were plausibly the same flock. Also, any swan flock
> information from section V (Sandy’s section) would be useful in determining
> whether the 40 seen there were unique flocks or flo

RE: [cayugabirds-l] Swan count for CBC

[Jody W Enck]

This discussion has been interesting to “watch” as it has unfolded.  I 
certainly understand the desire folks have to make the counts as accurate as 
possible.  Still, I wonder how all this adjusting of the numbers after-the-fact 
for just one species, and for just one year, influences the utility of the data 
for comparative purposes from year to year.  Given the year-to-year variability 
of the weather and its uncertain influence on both long-distance migration 
(e.g., of swans) and local movements (from and to feeders), I wonder if it 
simply makes the most sense to keep doing things the way they always have been 
done -- recognizing and even accepting that various species will be more or 
less likely to be affected in any given year with respect to whether they are 
double or triple counted, or undercounted.

If the purpose of the count (at least one of the major purposes) is to be able 
to examine long-term trends, then it seems that consistency of methodology from 
year-to-year should trump our noble attempts to improve within-year accuracy.

How far do Chickadees and other feeder birds move around on cold, blustery days 
like we had on January 1st?  The 6 feeder watchers in my neighborhood probably 
all had the same individual birds visit their feeders.  Seems rather endless to 
try to figure out how to deal with all the uncertainty in the data collection.  
I know the inquisitive scientist within me loves the challenge of trying to 
reduce that uncertainty, but a reduction in this kind of uncertainty probably 
will not enhance the utility of the data for its intended purpose.  Besides, 
the discoverer within me loves being out in horrible conditions just seeing 
what I can find, recognize, and learn.  I suppose it’s probably the same - to a 
lesser or greater degree- for everyone who looked for birds on the First.

Have fun,
Jody

Jody W. Enck, PhD
Human Dimensions of Natural Resources
Cornell Lab of Ornithology

From: Bill Evans
Sent: ‎January‎ ‎4‎, ‎2013 ‎10‎:‎05‎ ‎AM
To: CAYUGABIRDS-L
Subject: Re:[cayugabirds-l] Swan count for CBC

Last night I made of a Google map of the swan flock information reported to the 
listserv. I updated the trajectories and markers this morning adding some 
deductive/speculative text.
Cayuga Bird Club 2013 CBC Swan flock 
map<http://maps.google.com/maps/ms?ie=UTF&msa=0&msid=208086491899212349523.0004d26dc6966e4c7c382>
 (click markers to read text – if you have a Google acct and log in you can add 
information to the map)

The evidence suggests some flocks were double and even triple counted, but as 
Ken pointed out there are still some things that don’t add up. Two pieces of 
information that would help complete the picture would be more description on 
the location and trajectory of the flock of 21 (@ ~2:45pm) seen by Marty’s 
group. I don’t have that flock on the map and it doesn’t seem like it could 
have been the same flock of 19 I had at 2:15 or Ken had at 2PM, which were 
plausibly the same flock. Also, any swan flock information from section V 
(Sandy’s section) would be useful in determining whether the 40 seen there were 
unique flocks or flocks that had already been counted.

Anyone else who saw swan flocks on January 1st, please have a look at the map 
and see if your information matches or suggests additional unique flocks.

As of now there is a fairly solid case for a minimum of 163 southbound swans on 
count day. This presumes that swan flocks that exited the city of Ithaca in 
southbound flight didn’t return.

Bill E
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Re: Re:[cayugabirds-l] Swan count for CBC

[Bill Evans]

Last night I made of a Google map of the swan flock information reported to the 
listserv. I updated the trajectories and markers this morning adding some 
deductive/speculative text.

Cayuga Bird Club 2013 CBC Swan flock map (click markers to read text – if you 
have a Google acct and log in you can add information to the map)

The evidence suggests some flocks were double and even triple counted, but as 
Ken pointed out there are still some things that don’t add up. Two pieces of 
information that would help complete the picture would be more description on 
the location and trajectory of the flock of 21 (@ ~2:45pm) seen by Marty’s 
group. I don’t have that flock on the map and it doesn’t seem like it could 
have been the same flock of 19 I had at 2:15 or Ken had at 2PM, which were 
plausibly the same flock.  Also, any swan flock information from section V 
(Sandy’s section) would be useful in determining whether the 40 seen there were 
unique flocks or flocks that had already been counted.

Anyone else who saw swan flocks on January 1st, please have a look at the map 
and see if your information matches or suggests additional unique flocks.

As of now there is fairly solid case  for a minimum of 163 southbound swans on 
count day. This presumes that swan flocks that exited the city of Ithaca in 
southbound flight didn’t return.

Bill E 
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Re:[cayugabirds-l] Swan count for CBC

[Bill Evans]

Last night I made of a Google map of the swan flock information reported to the 
listserv. I updated the trajectories and markers this morning adding some 
deductive/speculative text.
Cayuga Bird Club 2013 CBC Swan flock map (click markers to read text – if you 
have a Google acct and log in you can add information to the map)

The evidence suggests some flocks were double and even triple counted, but as 
Ken pointed out there are still some things that don’t add up. Two pieces of 
information that would help complete the picture would be more description on 
the location and trajectory of the flock of 21 (@ ~2:45pm) seen by Marty’s 
group. I don’t have that flock on the map and it doesn’t seem like it could 
have been the same flock of 19 I had at 2:15 or Ken had at 2PM, which were 
plausibly the same flock. Also, any swan flock information from section V 
(Sandy’s section) would be useful in determining whether the 40 seen there were 
unique flocks or flocks that had already been counted.

Anyone else who saw swan flocks on January 1st, please have a look at the map 
and see if your information matches or suggests additional unique flocks.

As of now there is a fairly solid case for a minimum of 163 southbound swans on 
count day. This presumes that swan flocks that exited the city of Ithaca in 
southbound flight didn’t return.

Bill E 
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Re:[cayugabirds-l] Swan count for CBC

[Kenneth Victor Rosenberg]

O.K. I was counting along the Inlet all afternoon, and had flocks of swans for 
much of the time -- some of them were circling back and coalescing over the 
south end of the lake, making it difficult to get accurate counts. It seemed 
like at least some birds were "thinking" of settling down, but the frequent 
shooting probably dissuaded them.

My first flock of was roughly 20 birds (could have been 19 or 21 or 22 -- I was 
entering birds directly into BirdLog on my phone, so do not remember this 
initial flock count) -- this was a little before 2PM over the city golf course. 
Then as I was walking back from the jetty around 2:30, I counted 67 in the air 
at once, circling over the jetty woods back towards the lake, and then back 
south again. I assumed (conservatively) that this represented the total number 
of birds I had seen, but now I think probably not. Then later, at about 3:45, I 
another flock of 24 flying south over the Farmers Market area. I mistakenly 
reported a total of 99 for the day, but that should have been 101.  This plus 
Gary's 23 gave Area VII our total of 122 (should have been 124).

The 23 birds in Area !V were seen by John Fitzpatrick flying south over Ellis 
Hollow, so it would appear likely that these were the same as the Comstock 
Knoll birds, but likely different from the birds along Cayuga Inlet around the 
same time. It is very likely that many of the Area VII birds were the same as 
the ones I counted from the inlet, and it is likely that at least some of our 
birds passed over Bill further south.

Based on all this, I think a conservative minimum for swans would be Bill's 
total of 116 plus the easterly flock of 24 = 140. I suspect that there were 
indeed more, though, since the flock sizes don't really match up, and there 
were several times I heard swans over the jetty/golf course area and did not 
see them. I'll let Kevin figure it all out!

KEN


Ken Rosenberg
Conservation Science Program
Cornell Lab of Ornithology
607-254-2412
607-342-4594 (cell)
k...@cornell.edu

On Jan 3, 2013, at 8:42 PM, Marty Schlabach wrote:

Mary Jean and I saw a flock of 21 in Area VII mid-afternoon, probably about 
2:45pm, but I hadn’t noted the time for that sighting specifically.  I suppose 
I could have miscounted the flock as well, and it could have been the same as 
Bill’s flock of 19.  Our flock of 21 and Dave’s flocks of 14 and 60 made up 
Area VII’s 95.

Marty

From: 
bounce-72556136-3494...@list.cornell.edu
 [mailto:bounce-72556136-3494...@list.cornell.edu] On Behalf Of Gary Kohlenberg
Sent: Thursday, January 03, 2013 7:19 PM
To: CAYUGABIRDS-L
Subject: Re: [cayugabirds-l] More CBC birds for 2013

My count of Tundra Swans was a single flock of 23, flying over Comstock Knoll 
between 2:10-2:30 PM, headed SE. This is Area Vlll with a grand total of 122. I 
think the 23 individuals in Area lV may be the same flock as they were headed 
that way. Whoever counted those birds would know the time / number of their 
sighting, but it seems very coincidental.

Gary


On Jan 3, 2013, at 6:59 PM, mailto:nutter.d...@me.com>>
 mailto:nutter.d...@me.com>> wrote:

There was some discussion of potential multiple-counting of Tundra Swan flocks, 
but not a flock-by-flock analysis, and I don't think any adjustments were made 
among sectors at the compilation. Sector leaders may have tried to adjust among 
parties in their sector beforehand. I think it would be a good and interesting 
thing to try to figure out.

My notes from the compilation were:
Sector IV: 23
Sector V: 40
Sector VI: 116
Sector VII: 95
Sector VIII: 122
Total: 396

For my part, I was on Cliff Park Road just above Taylor Place on West Hill in 
the City of Ithaca when I heard and saw my first flock at 2:08pm. I counted 14 
birds, but I could have been off by one, so this could have been your group of 
15. They were east of me headed south up the Cayuga Inlet valley.

I was at the south end of Richard Place at 2:58pm when another flock went by, 
also well to my east, southbound up Inlet Valley. It was a larger group and 
harder to count because they were massed in a C which I was viewing from the 
side, not a simple V or line, and I had trouble getting my scope on them 
through the trees, so they were already past me when I finally got a look and 
then I looked at the time. I estimated 60 birds, but this could have been a 
flock of 53. They . .

Later I heard another flock but never saw them and did not count them or note 
the time.

I gave Sector VII leader Marty Schlabach the numbers and I think the times of 
my flocks. I don't know what accounted for the total of 95 for Sector VII, 
whether it was additional flock of 21 or someone else's more reliable counts 
overall.

--Dave Nutter

On Jan 03, 2013, at 03:03 PM, Bill Evans 
mailto:wrev...@clarityconnect.com>> wrote:
The other issue I’ve been wondering about is counts of migrating birds crossing 
the count circle, in