[Tweeters] More thoughts on "yellow-bellied tit"

[HAL MICHAEL]

When we consider any rarity remember that we actually "bird" a minuscule fraction of the available habitat.  We could have a wintering population of Bluetails that spend their whole winter in the (closed) Cedar River watershed.  We see stuff where we look. 

Even at a heavily birded place like Billy Frank NWR, if a bird spent its entire time no closer than 100m to any trail, would we see it?


Hal Michael
Board of Directors, Ecologists Without Borders http://ecowb.org/
Olympia WA
360-459-4005
360-791-7702 (C)
ucd880 at comcast.net




>     On 03/20/2022 12:21 PM Jim Neitzel <jim.neitzel at gmail.com> wrote:

> 

> 

>     To respond to Chris Kessler

>     "And while the Red-flanked Bluetail has been well documented and plainly

>     here, I note that the previous sightings on eBird are in West Coast cities

>     except for two inland western sightings, leading me to wonder if these are

>     not either ship-assisted birds or released/escaped "pet" birds. Still a

>     very cool bird, but have to wonder how it got here

> 

>     I'd be interested in others' thoughts on either issue"

> 

>     Remember the issue of viewer/sampling bias in Ebird- ebird reports come from where the birders are, not where the birds are. The sample will always be highly biased towards areas with lots of birders or popular sites that get birded regularly. Also, rarities will be seen more in areas with experienced birders who have them brought to their attention.

>     You can also search for how prevalent birds are in cage populations, and few highly migrant insectivores like this are kept in captivity.

>     --

>     James Neitzel, Ph.D.

>     Member of the Faculty, Biochemistry

>     The Evergreen State College

>     _______________________________________________

>     Tweeters mailing list

>     Tweeters at u.washington.edu

>     http://mailman11.u.washington.edu/mailman/listinfo/tweeters

> 

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman11.u.washington.edu/pipermail/tweeters/attachments/20220320/dd05c709/attachment.html>