10/24/06
Another nice day for a bird walk.
We got 16 species, well short of the record high of 23 for week 43
set last year. The record low was 8 in 1986 and if you
don't like to count that first year of 1986, and I don't,
then it was 11 in 2001. So we didn't do too badly.
See the birds_epoch plot at
http://birdwalks.caltech.edu/bird_data/two_plots.htm.
I guess the best bird was a Townsend's Warbler
in amongst some Bushtits on Holliston. Otherwise,
nothing too astounding. No Scrub Jay...sigh.
The stats:
The date: 10/24/06
The week number: 43
The walk number: 855
The weather: 73 F, sunny
The walkers: Alan Cummings, Glenn Hamell, Brendan Crill, Kent Potter
The birds (16):
Rock Dove
Mockingbird
House Sparrow
Mourning Dove
House Finch
Anna's Hummingbird
Acorn Woodpecker
Crow
Yellow-rumped Warbler
Band-tailed Pigeon
Red-tailed Hawk
Ruby-crowned Kinglet
Lesser Goldfinch
Bushtit
Raven
Townsend's Warbler
Respectfully submitted,
Alan Cummings
10/24/06
http://birdwalks.caltech.edu
10/17/06
What a nice day for a bird walk. Temperature in the high 60's and
partly cloudy skies. Very nice. And we saw some good birds.
We got 17 species, two short of the record high of 19 for week 42
seen in 1989 and 1997. The record low was 9 in 1986 and 1987.
See the birds_epoch plot at
http://birdwalks.caltech.edu/bird_data/two_plots.htm.
I looked at the probability charts before the walk
at http://birdwalks.caltech.edu/bird_data/probability_plots.htm
and predicted we'd see Ruby-crowned Kinglet and sure enough we did.
Saw several. They appeared just when they are supposed to.
Probably the most unusal sighting was a Western Meadowlark
clinging to the side of a palm tree like it was an Acorn Woodpecker.
Probably the best sighting was by Brendan who saw a Hermit
Thrush on his way back to his office. The pair of
Black-throated Gray Warblers in Tournament Park was a nice treat too.
All in all, a nice walk.
The stats:
The date: 10/17/06
The week number: 42
The walk number: 854
The weather: 68 F, partly cloudy
The walkers: Alan Cummings, Glenn Hamell, Brendan Crill
The birds (17):
Rock Dove
Scrub Jay
Mockingbird
House Finch
Anna's Hummingbird
Acorn Woodpecker
Crow
Yellow-rumped Warbler
Band-tailed Pigeon
Lesser Goldfinch
Black Phoebe
Ruby-crowned Kinglet
Black-throated Gray Warbler
Bushtit
Western Meadowlark
Hummingbird, Selasphorus
Hermit Thrush
Respectfully submitted,
Alan Cummings
10/17/06
http://birdwalks.caltech.edu
10/10/06
Well my guarantee of Yellow-rumped Warblers came through. We saw
lots of them. I did a little research of the records
to see how sharp the boundary is on the arrival of Yellow-rumped
Warblers at Caltech. Here are the ratios of sightings to opportunities
by week number, going back to 1986, for weeks 38, 39, 40,
41, and 42: 0/15, 3/15, 12/18, 18/19, and 13/13. So it appears
the arrival is spread over 3 weeks. Pretty sharp, especially considering
that the 18/19 for week 41 should really be 19/19 since
the one year we didn't see them on week 41 (1988), we did
see them a week earlier. So they had arrived by week 40.
So, the arrival is spread over about two weeks. To answer a
question posed by Brendan today, we should see Ruby-crowned
Kinglets next week. Take a look at the plots
at http://birdwalks.caltech.edu/bird_data/probability_plots.htm.
It was a beautiful day for a bird walk by the way -- about 70 F and
partly cloudy. And we got the average number based on 18 walks on week 41
from 1987 through 2005, 16 species. The record high for
week 41 is 21. The record low is 12. See the birds_epoch plot at
http://birdwalks.caltech.edu/bird_data/two_plots.htm.
The other bird of note was a Black-throated Gray Warbler,
out in the Sun with the Sun at our backs. How nice!
The stats:
The date: 10/10/06
The week number: 41
The walk number: 853
The weather: 70 F, partly cloudy
The walkers: Alan Cummings, Glenn Hamell, Kent Potter, Brendan Crill
The birds (16):
Scrub Jay
Mockingbird
House Finch
Anna's Hummingbird
Acorn Woodpecker
Crow
Red-tailed Hawk
Bushtit
Black Phoebe
Lesser Goldfinch
Yellow-rumped Warbler
Cooper's Hawk
Black-throated Gray Warbler
Starling
Band-tailed Pigeon
Hummingbird, Selasphorus
Respectfully submitted,
Alan Cummings
10/10/06
http://birdwalks.caltech.edu
10/3/06
Fall is here according to the birds. We saw Wilson's and
Townsend's Warbler and a White-crowned Sparrow.
We did not see Yellow-rumped Warbler but that bird
is guaranteed next week. I personally guarantee it.
Well, history guarantees it. Including the first year of
the walks in 1986, there has only been 1 week 41 without
a Yellow-rumped Warbler and that was in 1988. The odds
are in my favor on this guarantee. But by all means,
come out next week and see if I'm wrong. To view more
bird-sighting odds (based on the period 1996-2001 -- I do
need to update these!), go to
http://birdwalks.caltech.edu/bird_data/probability_plots.htm.
We saw 17 species, not a record by far -- that was
25 in 2004 -- but respectable. See the birds_epoch plot at
http://birdwalks.caltech.edu/bird_data/two_plots.htm.
The prize bird of the day goes to Brendan Crill and Kent
Potter who stayed with a tree while the rest of us moved on and
came up with a Red-breasted Sapsucker. We don't see many
sapsuckers period and I think that must be the earliest ever
sighting in the fall/winter season. It was not in the
sapsucker tree by the way. It was over by the recycling
bins in the north part of campus. Good job Brendan and Kent!
The stats:
The date: 10/3/06
The week number: 40
The walk number: 852
The weather: 75 F, sunny
The walkers: Alan Cummings, Glenn Hamell, Jim Carlblom, Brendan Crill, Kent Potter
The birds (17):
Rock Pigeon
Scrub Jay
Mockingbird
Mourning Dove
House Finch
Anna's Hummingbird
Acorn Woodpecker
Crow
Red-tailed Hawk
Black Phoebe
Bushtit
White-crowned Sparrow
Lesser Goldfinch
Wilson's Warbler
Townsend's Warbler
Red-breasted Sapsucker
Hummingbird, Selasphorus
Respectfully submitted,
Alan Cummings
10/3/06
http://birdwalks.caltech.edu