bird data > past walk reports

7/25/11

Missing, needs to be reconstructed.

7/18/11

We came up with 12 species, a very reasonable total for week 29 (the median is 11) but a stolid 4 below the record of 16.

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

Had we been counting butterflies and dragonflies, we would have had a great walk total. We saw a lot of whites, a couple sulfurs, west coast ladies, swallowtails, and a gulf fritillary. I'm sure we would also have noticed many smaller species had we been looking very hard (I did notice some skippers) but, alas, the butterflies count only as flickering minuets as they color the day.

To me, the walks are really all about the journey but, usually in a walk report, you find some trumpeting call over the appearance of a rare for Caltech bird or, perhaps, a relatively more common bird flushed to prominence through a terrific look. This week, the journey held no such obvious virtuoso. Our Cooper's Hawk, though a nicely framed and lighted flyby view, was all too brief. The identification of the lesser goldfinches was both visually and vocally competent but neither was inspired and writing about a three second aerial view of rock pigeons flying across California Boulevard seems more than a little excessive. So, instead, I lift a paean to the bushtit. This is, I think, a badly underappreciated bird. I've seen birders in other places walking along in a huddled little flock that stops suddenly as one of them sees a small bird rustling about in a bush. At first, they are all very attentive, each trying to determine the species, and then you hear the word "bushtit!" with a sneering lilt. The binoculars lower like a palpable sigh and the birders avert their eyes. It is as if there were a subliminal belief that the gnatcatcher they really want to see is offended by someone spending the time to appreciate a common bushtit.

This week, Ashish was the first to notice our bushtits. He was without binoculars but he saw a couple of small birds flying from one oak on our side of Wilson near Morrisroe to other side of the street. His impression, and the one you usually get at a distance for bushtits, is of a tiny puffball of grayish brown with a longish tail, not definitive necessarily but highly suspicious. By now, three or four of us were watching when a couple more of these little birds flew over to join the first group, followed by a few more, another couple and then, finally, as if drawn by peer gravity or word of food, a group of twenty or so crossed in a single visual whoosh. Bushtits for sure. Having confidently identified them, we didn't bother to cross the street and I feel a pang of regret over not tasking a little time for closer inspection. It would have briefly taken us off of Caltech property and slowed the walk, though not by a lot. We were allowing bird bagging to triumph over a more in depth appreciation of a single species.

Now, you might not think there is much to see beyond identifying a bushtit and you would have a lot of company among some very good birders but the attitude is all wrong. Regarding a bushtit is an exercise in subtlety. After all, if you read a description of bushtits in a field guide, the code words (or synonyms, thereof) are drab, drab, drab gray to brown energetic little birds with long tails that tend to run in flocks. That about covers it. They are certainly energetic. I once took 84 pictures of bushtits over the course of a few minutes in my backyard and upon downloading the files, I found myself with images of bare twigs, clusters of leaves, flowers (this was in a river silk tree in bloom), out of focus pieces of bushtits and one, more or less, in focus bird. I've had better luck with kinglets. Our bushtits are grayish brown with the gray mostly reserved for the wings and tail and brown trending from the head and sides grading down to a paler breast. There are some regional variations in the plumage details but you wouldn't mistake any of these guys for anything other than a bushtit unless you are a very serious splitter. I can, however, give you an extra identification trick that opens into one of the vistas I find so intriguing about these birds. Look into a bushtit's eye. A solid deep dark brown indicates a male. If the iris appears yellow or creamy with a black pupil, you have a female. Now, here's the interesting thing. If you only look at one bird in the flock in this way, the odds are that you are going to be looking at a male because the flock will have about a third more males than females. A bushtit flock is basically an extended set of family groups and the way genetic diversity is maintained is that some of the females go off, after fledging, to find a new flock and a lot of them don't make it. Within your flock, you are in constant communication with everybody else. If there is a hawk, one of your friends will give an alarm call and you will not be caught unaware. You will be safe. If a clot of beetle larvae just hatched, one of your buddies will find them and tell you where the table has been set. The evening is cold? You get to huddle with the rest of the flock and conserve energy. Being by yourself is very dangerous and requires a lot of extra food that may be hard to find. But what about all those frustrated males, you might say. Not a problem. During the winter and spring, bushtits pair off and leave the flock. They build a nest that looks a lot like a child's insulated sock (I find them periodically in my yard) and the entire family spends the night together. Often, there is a helper who just happens to be an unrelated male who didn't get a mate. He forages for the chicks and spends the night in the sock with everybody else. "Aha," you may be thinking, but these are not acorn woodpeckers. There are no affairs in the bushtit world. So, what's in it for the helper? If it's a good year, the female will try for a second brood and, usually, she will select the helper as her new mate. A female bushtit is serially monogamous. And the male? Well, he knows how the bread is buttered. Bushtits have it all figured out.

In other news, we didn't see a Nuttall's woodpecker near the nest of last week but Melanie said a female mallard was at the pond at 7 PM on Monday. Perhaps, there is a duck in our future.

The date: 7/18/11
The week number: 29
The walk number: 1100
The weather: 84°F, sunny


The walkers: Alan Cummings, Kent Potter, John Beckett, Melanie Channon, Vicky Brennan, Vivica Sapin-Areeda, Ashish Mahabal

The birds (12):

Rock Pigeon
Northern Mockingbird
House Sparrow
House Finch
Crow
Hummingbird, Selasphorus
Red-masked Parakeet
Bushtit
Black Phoebe
Parrot, species
Lesser Goldfinch
Cooper's Hawk

-- by John Beckett

Respectfully submitted,
Alan Cummings
7/20/11
http://birdwalks.caltech.edu/index.html




7/11/11

Not so long ago, we were getting mildly disappointed if we logged less than thirty species. This week, we saw "only" 15 and it tied the record originally set in 2002 and matched in 2007, 2008 and, last but surely not least, in 2011. Fifteen is clearly a popular number for week 28.

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

I find myself in summer looking for secrets in the mundane. Yes, there are elegant summer visitors like white-throated swifts I never tire of watching but most of the available birds on campus are resident throughout the year. To me, each of them, actually every bird, is a cacophony of meshing maybes. Sometimes, a glance is definitive. We saw a flight of three birds zipping overhead, perhaps only two seconds, none with binoculars, and yet there was no doubt among us that we had seen a small band of band tailed pigeons. We hear a song that can be nothing else, a bulbul. Others we never resolved. The lighting was bad, the bird was shy, the look too brief, and the one note call, however hauntingly reminiscent of something not quite on the tip of your tongue, was not quite enough. This week it was a tale of tail. There is a prominent eucalyptus tree north of the recycling center at the north end of campus and perched patiently for us on a large branch was a largish hawk. We never got a view of the breast or face. No call came. There was no flight off the perch. The head never turned and the lighting was not great. We had a back and we had a tail. So what did that get us? The most prominent overall features were a really long tail extending well beyond the wing tips, a relatively lithe appearance, brownish coloring to the back with a more grayish tail and no spots on the back (no spangles). This said something along the accipiter line like a Cooper's or a sharp-shinned hawk rather than a buteo like a red-tailed or red-shouldered hawk. The end of the tail, which was closely held, had subtle bars and was clearly rounded, which argued against a sharp-shinned hawk, as did the size (this was definitely a big bird, presumably female) and the season. We have admittedly had a few summer sharp shinned hawks sightings over the years (you don't need all the fingers of one hand to count them) but the vast majority of sharp shins are up in the northern US and Canada right now and they are far rarer around Caltech in the summer than Cooper's hawks. Exotics (to Caltech) like merlins (too small) and northern harriers (too big a tail to wing ratio) also failed. We had a Cooper's hawk. We have had some seriously cool encounters with Cooper's hawks that were much more obviously extraordinary and close-up and they are not particularly uncommon even in summer but a bird that forces you to work with less is extraordinary in its own right and in many ways it is working the puzzle of a small fraction of the potential field markings that validates the process of birding. We actually made a quick id on the Coopers but somehow she seemed to bring out our feral birders. I like that feeling.

We also saw a female Nuttall's spend a lot of time poking her head into a hole just west of the Tournament Park parking lot, occasionally even disappearing except for the tip of her tail. No doubt she had a very good reason for doing this and, although this would be quite late in the season for laying eggs, there is a decent chance the hole has some chicks and that she will continue to have several good reasons to visit over the next week or two. We didn't see the male but I'm sure he was somewhere in the general vicinity.

The record tying bird, although we didn't know it at the time, was seen near the end of the walk opposite Parson-Gates. This was a juvenile common raven, back to commune with fond memories, perhaps a month old, of free food and total protection. The times have changed dramatically and the lost reality of the nest is something every juvenile corvid has to come to terms with. It's an unforgiving world out there.

We would have made 16 species if our cat food mallard had been accommodating but he was clearly molting last week with the bright green neck-band of the breeding season rapidly turning into a muddy brownish goo. It seems likely that he has gone off to find a large body of water to complete the molt and he won't be back again this summer (he will be flightless for a while as he drops a lot of flight feathers, all at the same time rather than one at a time like most birds). Unless some hen decides to stop by (they molt a little later in the season), we are probably out of ducks for a while but you never know. We'll be checking...

The date: 7/11/11
The week number: 28
The walk number: 1099
The weather: 73°F, sunny

The walkers: Alan Cummings, Viveca Sapin-Areeda, John Beckett, Vicky Brennan

The birds (15):

Northern Mockingbird
House Sparrow
Mourning Dove
House Finch
Anna's Hummingbird
Crow
Red-masked Parakeet
Red-whiskered Bulbul
Black Phoebe
Hummingbird, Selasphorus
Nuttall's Woodpecker
Lesser Goldfinch
Band-tailed Pigeon
Cooper's Hawk
Common Raven

-- by John Beckett


Respectfully submitted,
Alan Cummings
7/15/11

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




7/5/11

Just a short one this time as I'm swamped on the science/project manager side of my life. We had an average walk, recording 12 species. We were right on the median but a shade below the average for a week 27, so we came up with a slightly negative walk score. First one of those we've had since Valentine's Day, 20 weeks ago.

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

The heat probably dissuaded some walkers from walking as we only had three people total. There was not a lot to brag about on the walk. The highlight was that we all survived and nobody even passed out.

The date: 7/5/11
The week number: 27
The walk number: 1098
The weather: 90°F, partly cloudy

The walkers: Alan Cummings, Vivica Sapin-Areeda, John Beckett

The birds (12):

Northern Mockingbird
House Sparrow
Mourning Dove
House Finch
Anna's Hummingbird
Crow
Mallard
Red-tailed Hawk
Red-masked Parakeet
White-throated Swift
Black Phoebe
Lesser Goldfinch

Respectfully submitted,
Alan Cummings
7/8/11

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




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