I'm glad I'm not the only one that was put out by the admonishment against
using the phrase "conservative" when referring to a count or estimate. To
me it means "at least." Much of the time it is used to justify a number
that has been flagged in eBird as being "too high." I think it is fair to
say that we as humans are generally terrible at estimating large numbers of
things without using additional tools like photography, and counting things
moving back and forth without knowing if they're the same individuals is
especially difficult.
Personally, I'm pretty happy nobody's gonna put me in jail for reporting
"conservative" numbers because that's how I roll...
Best birding,
Stefan
On Mon, Dec 16, 2019 at 10:20 PM Randy Winstead <randywendy@xxxxxxx> wrote:
I can understand both sides of this discussion to a certain extent. I have
used “conservative count” at times when I perhaps should have used
“conservative estimate” or simply “estimate”.
However, I can sympathize with Reuben’s LeConte’s Sparrow illustration.
There is a difference between counting Coots in a small pond and counting
any number of birds, even large and solitary ones, in a refuge in which the
trails sometimes criss-cross in a figure eight pattern because of levees or
other features, and the birds are flying back and forth across the refuge.
You can have an “exact count” of 55 birds when there are only 15 on the
refuge. You may have counted exactly 55, but you suspect that there are
actually somewhere between 10 and 30. So you give a “conservative estimate”
of 15. Or perhaps you know that there are at least 15, and you have counted
what you are reasonably certain is the same group of 15 three times:
therefore 45 birds “counted”, but in reality only 15 birds. Then you see an
additional 10 birds that may or may not be part of the same group. Do you
count them or not? There are either 15 or 25 birds on the refuge. Opting
for the conservative side, you report a “conservative count” of 15.
On the hand, I don’t often use a mobile app, mainly because I often have
to go back home and examine photos or voice recordings to determine whether
it was a Greater Scaup or a Lesser Scaup, a Common Tern or a Forster’s
Tern, a Louisiana Waterthrush or a Swainson’s Warbler. Therefore I don’t
have to report “approximately 247” birds. I can round up or down when I add
things up and type in my report. This helps resolve the mathematical
monstrosity of significant figures. On this I can sympathize with the
article to which Scott linked and the concept of significant figures and
false precision.
I once saw a large flock of turkeys in a field. I counted them. There were
100. Not 99; not 101. There were 100. Sigh… I looked for a while trying to
come up with 101, but to no avail. So I noted “exact count” on my report.
It happens.
Do the best that you can. Nobody is going to put you in jail for missing
it by a few. Good birding.
Randy Winstead
Maryville, Blount County
On Monday, December 16, 2019, 09:56:09 PM EST, Ruben Stoll <
birdchaserrws@xxxxxxxxx> wrote:
For those of you that find the term “conservative count” or
“conservative estimate” confusing, here is what they mean to me, and I
actually find them quite useful.
(I’ve personally never heard of a “liberal count” so I’ll just leave
that term to you liberals).
CONSERVATIVE COUNT: I’m walking through a field of Leconte’s Sparrow
habitat and I count 39 Leconte’s Sparrows flushing ahead of me over the
course of 20 minutes as I walk all the way across the field. 18 of them
come back up exactly where they had dropped in earlier, and therefore are
most likely the same birds being counted again. I throw those out as
recounts. That leaves 21 different birds, but out of those 21, another 6
could easily have run a ways and been counted again when they flew a second
time. I throw those out as well. That leaves 15 birds that flew back
around or far enough to the side to be confirmed as “different” birds. The
count is therefore 15. This is a conservative count. It’s not a 1 by 1
count. That’s usually not possible in field conditions. It’s not an
accurate count. That would be much higher.
CONSERVATIVE ESTIMATE:
I didn’t take the time to count the Mallards along Refuge Road today
because I didn’t have time. (If I did I would accomplish little else). Two
weeks ago I did try to count them by 10s, 50s, 100s, (They’re scattered
everywhere) and I came up with 6,000 though that count could easily be off
by several thousand.
Today I’m pretty sure the numbers are still just as high as they were
last time I was here, and might be anywhere from 4,000 to 20,000 along
Refuge Road. So I take the low number and report 4,000 as a conservative
estimate. It’s definitely not a count and it’s also not accurate but it’s
better than an x and it’s an amount that I can easily verify if necessary.
(Of course, on a Christmas Bird Count I usually don’t get off this easily).
Something else that I noticed happens a lot if you actually get out
there in real life. At least it happens to me:
I start an ebird checklist. Three Starlings fly over, so I enter 3
Starlings. Ten more Starlings fly over so I enter 10 more. 15 minutes later
a big flock of Starlings comes through, all headed in the same direction. I
frantically count Starlings by tens, and I round it off to 500, which I
think was reasonably accurate. Unfortunately, now I have a grand total of
513 European Starlings, and it’s flagged on ebird. I realize this is an
irritating number for some people but it’s the closest I could get and I
really don’t have time to go back and take off those first three birds.
This happens all the time when using the mobile app. If you guys wanna
quibble about these numbers you clearly have more time on your hands than I
do.
Ruben Stoll, Centerville Tennessee.
On Sun, Dec 15, 2019 at 10:50 PM Scott Somershoe <ssomershoe@xxxxxxxxx>
wrote:
All,
Here is a good essay on how to count and report birds for your eBird
lists. There are a few specific points in here that rise to the top during
CBC time, especially when counting large flocks of birds and reporting a
“conservative count or estimate” of which no count is conservative not
liberal. I encourage you all to read this. It’s great!
http://cowyebird.blogspot.com/2019/12/details-provided-about-counting.html?m=1
Scott Somershoe
Littleton CO
Sent from my iPhone
