bird data > past walk reports

9/24/12

We observed 18 species, which just ekes out a positive score by being one above the preexisting median for week 39. We were not even within hailing distance of the record of 24, which was set in 2004 but we were well above the worst showing of 7. We had two and a maybe for notable birds.

See the plots at http://birdwalks.caltech.edu/bird_data/species_time.html and http://birdwalks.caltech.edu/bird_data/two_plots.htm

The maybe bird came in the form of a pair of birds fluttering to the north as seen from the Maintenance yard. Now, the flight pattern said swift and I managed to briefly get a glass on one of them. To the extent I could tell, it looked pretty dark and relatively monotonic. So, I'm practically salivating. Bird of the week! Bird of the week! I'm thinking Vaux's swift. Bird of the week! Weeks 38-39 are prime time for Vaux's swifts (8 of our 20 sightings have come in weeks 38 or 39). However, nobody's look is good enough to push anybody around and Kent thought he saw some white on one of the birds, which would make them white-throated swifts. I could say that white throated swifts would be a really anomalous sighting for week 39, so that these were much more likely to be Vaux's swifts, but it wouldn't be true. We have a significant pulse of sightings at weeks 39-40 on the Caltech bird walk, (never mind that our pair was heading north). We are, sad to say, left at swift species and I remain on the hunt for a bird of the week.

The second potential bird of the week came in Tournament Park. Darren thinks he hears a yellow-rumped warbler and he and Alan work for a visual but they only come up with a bird of the right size and no viable field markings. There is no butter butt to furnish thought. There is no clear yellow and no good sighting for the group. It is, I suppose, a legitimate sighting but I HATE it. I look for seasonal markers to explode the time, charged like the breath of a lion's decaying flesh. It should roar, calling every particle into an aligning lattice of everlasting Fall. I could, I suppose, just not let Fall happen until I see a yellow-rump for myself but I'm afraid the Fall is here whether I like it or not. This time it whimpered like a lost sigh in a fog. A balance has come and gone. The second Darren derivative has said that it is so. The season has officially changed. A yellow-rump is here in week 39 and I didn't see him. I am annoyed.

Typically, we see out first yellow-rump of the season in week 40 or 41. Of 24 years of Caltech bird walk in which there is sufficient data to be confident of the first week of sighting, we had one first Fall yellow-rump in week 38, four in week 39, including this year, nine in week 40 and ten in week 41. So, our Fall comes early. It's time to start looking for ruby crowned kinglets along with Townsend's and black throated gray warblers but I'll believe they are here when I see them.

Although the yellow-rumped warbler is an important seasonal marker species for us, it isn't the bird of the week. This bird came to us at the tail end of the walk when Viveca notices a pair of birds zipping around a tree trunk. The behavior said nuthatch. One was clearly a white-breasted nuthatch. The birds appeared to be in a somewhat antagonistic relationship, although there was none of the raised tail or back feathers signaling that a real fight was in the offing. Still, we were hoping that the chasing might mean that one of them was a red-breasted nuthatch, which would have been a new bird for the Caltech bird walk. However, it soon becomes clear that both birds are white-breasted nuthatches. Perhaps, these are siblings dispersing from their natal territory.

We have only six white-breasted nuthatch sightings prior to this year, the last in 2002. Now, we get sightings in successive weeks, so this is a big event. The timing is not anomalous in the sense that our sightings have been evenly split between Fall (weeks 38-43) and winter (weeks 2-9). Most likely this is a pair of dispersing juveniles but it could have been a pair of adults as nuthatches will pair bond over multiple years and stick together through the winter. How's that for certitude? Last week's sighting was in Tournament Park, so there is a good chance that our birds from this week are different individuals from the one Kent and Vicky picked up last week.

To what do we owe the honor of all these nuthatches? The two usual suspects for this type of anomalous sighting are that this is either an aftermath of the Station Fire or that we have a freak bird or two. The common yellowthroat of last year was likely an example of the latter. However, given that people in the group have been commenting recently on an unusual abundance of nuthatches in Sierra Madre, which is upslope from us, and given the possibility that we have seen three different nuthatches over two weeks, I'm inclined to go with the Station fire theory for our nuthatches. If you get a good year followed by a bad or at least less good year, you will often have the eruption of a species into areas outside its normal range as young birds, especially, look around for new habitat. With the burned out region of the Station Fire providing few opportunities for new territory to the north without flying over an extensive region of blight, young hearts glean to the south. Nuthatches tend to be semi-resident, so if there are enough insects to be gleaned from the local bark, we may be greeting the equivalent of the great chickadee invasion of the last couple of years.

The date: 9/24/2012
The week number: 39
The walk number: 1162
The weather: 86F, sunny

The walkers: Alan Cummings, Kent Potter, John Beckett, Darren Dowell, Viveca Sapin-Areeda, Vicky Brennan

The birds (18):

Rock Pigeon
Mourning Dove
House Finch
Anna's Hummingbird
American Crow
Lesser Goldfinch
Yellow rumped Warbler
Swift, species
Bewick's Wren
Red-whiskered Bulbul
Black Phoebe
Yellow-chevroned Parakeet
Nuttall's Woodpecker
Hummingbird, Selasphorus
Mountain Chickadee
Bushtit
House Wren
White-breasted Nuthatch

--- John Beckett

Respectfully submitted,
Alan Cummings
10/5/12

http://birdwalks.caltech.edu/index.html




9/17/12

It was a warm, sunny, mid-September Monday. But not nearly as warm as recent Mondays. Which is good. Vicky was a little late, Kent was a little later, so each was concerned about doing a solo walk. We met near the maintenance yard with no birds each. The yard and Tournament Park and its parking lot yielded 13 birds. Note that this is also the total for the day. Possibly a California Towhee, by ear, around the athletic field, but probably the Phoebe we saw later. Two separate little brown birds on Holliston---maybe one a House Finch, but nothing to meet the high standard for Caltech Walkers. Only the Deep South (Campus) produced today.

See the plots at http://birdwalks.caltech.edu/bird_data/species_time.html and http://birdwalks.caltech.edu/bird_data/two_plots.htm

The White-Breasted Nuthatch, Orange-Crowned Warbler, and Mountain Chickadee showed up close together in time and space, so it's three birds-for-the-week. Three in one is good, since I know neither enough natural history nor birding statistics to write much else. It was a pleasant walk, not too many birds, but, particularly with the Nuthatch, some interesting ones.

The date: 9/17/2012
The week number: 38
The walk number: 1161
The weather: ~85 F, sunny

The walkers: Vicky Brennan, Kent Potter

The birds (13):

Scrub Jay
Mourning Dove
Anna's Hummingbird
Acorn Woodpecker
American Crow
Bushtits
Black Phoebe
Hummingbird, Selasphorus
Lesser Goldfinch
House Wren
White-Breasted Nuthatch
Orange-Crowned Warbler
Mountain Chickadee

--- Kent Potter

Respectfully submitted,
Alan Cummings
10/4/12

http://birdwalks.caltech.edu/index.html




9/10/12

Hmmmm.. this happened so long ago, I've forgotten what happened. So, this report will be short.

We walked, we ovserved some birds, and we recorded what we observed. We only saw 8 species. Fortunately, the record low for the week was 6.

See the plots at http://birdwalks.caltech.edu/bird_data/species_time.html and http://birdwalks.caltech.edu/bird_data/two_plots.htm

The date: 9/10/2012
The week number: 37
The walk number: 1160
The weather: 87 F, sunny

The walkers: Alan Cummings, Kent Potter, Vicky Brennan

The birds (8):

Rock Pigeon
Anna's Hummingbird
Acorn Woodpecker
American Crow
Hummingbird, Selasphorus
Black-chinned Hummingbird
Swift, sp.
Bushtit

Respectfully submitted,
Alan Cummings
10/3/12

http://birdwalks.caltech.edu/index.html




9/4/12

We each have our own little fears in a bird walk. For me, there is the haven mind fruiting birds and easing purple berries into red or green, or planting a single chirp that rises in like a faint echo of the chorus dawn into something I know. Wishing makes it so. I could turn a crown of thorns into a pigeon or an Anna's into an Allen's. Do I imagine a flash of brown as he speeds away? There is no one else to say. It is all between the me and the haven moi. It is why there should always be at least two people on a bird walk. There is the hive mind but there are only free lunches for dead crows and even the carrion has to make a living. This week it finally happened. I have been on more than a hundred Caltech bird walks, always with others; sometimes on a pleasant Fall migratory day, with many others. This time, I reach the starting point of the walk and find only the echo of parties from the past. I proceed to the Maintenance yard, where I flush a big flock of variably aged young mourning doves. Some of them have short tails and are still growing out feathered cheeks but see no other walkers. Tournament Park is full of ghosts and lesser goldfinches. Darren is probably up at JPL. Viveca is gone. Alan is off having fun. It's too hot for Vicky and Kent, who seems to have a sixth sense for undersubscribed walks, leaves only the afterimage of a white beard. I am alone in a haven mind and must be careful.

Unfortunately, for me, the birds are also being careful and, at least to my ears, rather quiet. Still it comes to a yielding struggle. I hear a crow. I hear a house finch and somehow, I catch the accent just right and whistle over a dozen. I see a bulbul. It didn't talk but moved in an attempt to triangulate my strange call. I manage to pish up a house sparrow, whose querulous gaze turns like a sneer into a diving drop. His hollowed court swallowed by leaves brushing the tunneling breeze of a poltgergeist. Well, you say, " You must be one of those dreamers who sees what should be seen or what should not." Maybe. I will say that I know what I saw and heard and I saw what I knew. The total number of species for the day was 14, which is reasonably good walk for a week 36 walk. The record is 18, set in 2009, and I don't think I could have met that without doubling up on time, tempting, perhaps, but too hot. However, the median is only 12, so my solitary saunter officially qualifies as being respectable.

See the plots at http://birdwalks.caltech.edu/bird_data/species_time.html and http://birdwalks.caltech.edu/bird_data/two_plots.htm

I suppose the highlight bird has to be the Bewick's wren. As I come up along the path lacing the Throop ponds, I am disappointed but not surprised to see no mallard, not even a nitrogenous hint. However, as I glance down into the Indian hawthorns on the other side of the path, I see a flash of bird in the underbrush. He is razzing something as he works the bushes. Getting louder by the second, he suddenly pops up to a tree fork, very nearly at eye level and continues to scold, his tail straight up and his eyebrow blazing. He is now looking right at me. What have I done to deserve this? Perhaps, he knows that I tend to associate with that riff raff Alan and his smart phone. Perhaps, he is scolding another bird still hiding in the bushes (a common yellowthroat would be nice). He cusses for another few seconds and he then flies directly over my head, landing about five meters up and on the other side of the path. He proceeds to forage, ignoring me and any other annoyance. It is quiet again in the avian world and, if I was important to the interaction, I am now, as I should be, unimportant but we have our tenth Bewick's wren sighting of the year.

The date: 9/4/2012
The week number: 36
The walk number: 1159
The weather: 94°F, sunny

The walkers: John Beckett

The birds (14):

House Sparrow
Mourning Dove
House Finch
Anna's Hummingbird
Acorn Woodpecker
American Crow
Lesser Goldfinch
Hummingbird, Selasphorus
Red-masked Parakeet
Black-chinned Hummingbird
Red-whiskered Bulbul
Common Raven
Bewick's Wren
Black Phoebe

--- John Beckett

Respectfully submitted,
Alan Cummings
10/2/12

http://birdwalks.caltech.edu/index.html




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