[orebird] Oregon eBird: Canada Goose filter settings

From: David Irons <llsdirons@xxxxxxx>
To: "orebird@xxxxxxxxxxxxx" <orebird@xxxxxxxxxxxxx>, Marshall Iliff <mji26@xxxxxxxxxxx>, Brian Sullivan <bls42@xxxxxxxxxxx>, Christopher Wood <clw37@xxxxxxxxxxx>, Ian Davies <id99@xxxxxxxxxxx>
Date: Wed, 4 Mar 2015 09:35:25 +0000
Greetings All,

After an exchange with Dave Hewitt over the Canada Goose filter settings for 
Klamath County, I took a spin through the filter settings for all 36 of 
Oregon's counties looking specifically at "Canada Goose" and "Canada Goose 
(moffitti/maxima). To be brutally frank, they are a mess. Below is a listing of 
the primary problems.

1. Many counties seem to have a filter setting that was copied from another 
county rather than based on the reality of what one might expect to actually 
find in that county. It is common to see the Canada Goose filter set at 2000 
and the (moffitti/maxima) filter set at 350. Filters should be set in a way 
that reflects the reality of what one might expect to find in that county. In 
many of the counties with this setting, I think you would be hard-pressed to 
find even 500 Canada Geese in a single day any time of year.

2. Following up on the copy cat setting above: In the vast majority of these 
counties, only (moffiti/maxima) occurs, so where do the other 1650 birds come 
from? If you have both a species and one or more subspecies listed with filters 
set above zero. The big number (in this case straight Canada Goose) should 
approximate the sum total of all the little numbers (those set for various 
Canada Goose subspecies). If the only Canadas in your county are large 
pale-breasted birds (moffitti/maxima), then doesn't it make sense for the 
filter setting for the default subspecies to match or be pretty darn close to 
the filter setting for just the species? 

3. Filter levels for Canada Goose are generally too high. There are a number of 
counties with the Canada Goose filter set at 10,000 during the winter months. I 
have spent a lot of time looking at white-cheeked geese and I have birded in 
all of Oregon's 36 counties. I've never seen anywhere near 10,000 Canada Geese 
in one county in a single day. I suppose if you were able to drive around and 
see all of the Canada Geese in Klamath County or all of the Canada Geese on 
Sauvie Island during the winter months, you might approach a tally of 10,000, 
but it would take some doing. Setting the number this high allows users to 
mis-report Cackling Geese as Canadas. Seeing 10,000+ Cackling Geese in a day is 
pretty easy to do in every Willamette Valley county with the possible exception 
of Clackamas and it's tough in Linn. Even when the Dusky Canadas are in for the 
winter, seeing more than 1000 Canadas in a day in most Willamette Valley 
counties is a challenge. Aside from Klamath County, I think one would be 
hard-pressed to find 1000 in any of the other eastside counties regardless of 
the time of year. 

4. Knowing the subspecies and their distribution. I noticed that both the 
Jackson and Josephine County checklists include "Canada Goose 
(occidentalis/fulva)" with a filter setting of 100 from October–March and yet 
"Canada Goose (moffitti/maxima) does not appear in the checklist for either 
county. I haven't done a lot of winter birding in these counties, but I know 
that moffitti/maxima are resident in these counties and that any other taxa of 
white-cheeked geese, including Dusky Canada, are quite sparse. I have a hard 
time believing that Dusky Canada is at all regular in the upper Rogue and 
Illinois valleys and I would be shocked to see more than a small group (5-10 
birds) of this form in that part of Oregon. The total population of Dusky 
Canada Goose numbers fewer than 10,000 birds based on the most recent reports 
that I can find. Nearly all of these birds winter between Ridgefield NWR in SW 
Washington and Eugene, with perhaps 1000-1500 wintering on the northern Oregon 
Coast (mostly Tillamook and Clatsop counties). Even in Eugene, finding 100 
Duskies in a day is tough. 

I encourage each of you to take a critical look at the Canada Goose and Canada 
Goose (moffitti/maxima) settings in your respective counties and then compare 
them with the numbers that you are actually seeing. I would say that away from 
the Willamette Valley and the northern coast counties, the Canada Goose and 
Canada Goose (moffitti/maxima) filter settings should be nearly identical. This 
is a species and group of associated subspecies that reflects how inconsistent 
our filter settings are at times. If you need help or want recommendations for 
the settings in your county, don't hesitate to ask me.

Dave Irons
[orebird] Oregon eBird: Canada Goose filter settings

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