bird data > past walk reports

11/26/12

The record for week 48 is 22 set in 1999 and matched in 2002, the latter no doubt a tribute to the amazing ears and eyes of Jon Feenstra. Well, this week we had Darren Dowell on the walk and we also have a new total species record for a week 48 Caltech bird walk with 25. I have to admit that it felt respectable at the time (generally defined as 20+ in the winter) but it didn't feel like a record setting walk. However, histrionics are unnecessary when you are making history. We had a smooth pleasant quiet walk with a steady accumulation of species that somehow landed us on a pedestal. Maybe it was the lack of parrots and parakeets but this was a very quiet record. Nevertheless, we will take it. We were, of course, above the median of 18 but we also doubled up on the record low of 12.

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 was the mountain chickadee because it gave us eleven for the year. 2011 (also eleven sightings) and 2012 are now the outstanding chickadee years of all time (two sightings in 1987 constitute the third best showing). I called last year "the year of the chickadee" because it rose like a whale breaching through a calm sea. There hadn't been a chickadee sighting in four years and never more than two in the same year. Suddenly, we seemed to have chickadees everywhere. So, seeing a lot of chickadees this year was not a surprise because we had been prepared for it but, going forward, will it be a relaxation to the norm of rare chickadees or is it going to be an expansion of range to Caltech? Will it be like lesser goldfinches flaming in or spotted doves flaming out? I suspect a decline to normality. Why? Going by calendar year is actually a poor way of capturing patterns for winter residents, even if they are just swooping down the hill or crossing a single mountain range. A better way to look at them is through a July to July format. Let's take our chickadees. All eleven chickadee sightings in 2011 occurred after July, consistent with juvenile dispersal starting in August, followed by adults and wintering birds. So, for the shifted year of July 31, 2010 to July 31, 2011, you have zero sightings. For the shifted year of July 31, 2011 to July 31, 2012, you have eleven from 2011 and then six from the first half of 2012. That strongly suggests an eruption starting in the Fall of 2011 and an eruptive season that yielded 17 sightings based on a shifted calendar. In the current calendar shifted season, July 2012 to July 2013, we have five sightings, so far. We are behind. We had eight sightings by week 48 in the previous year. Does that mean that chickadees are soon to be lost from view? Not necessarily. Eruptions sometimes lead to range expansions because some of the dispersing birds find stable habitat and stick around or come back the following winter after breeding. You might not have the big blast of the eruption year but you also wouldn't relax back to the previous chickadee state, which was basically nothing. We shall see and, since we are talking about chickadees, we shall hear. And, since we are talking about chickadees, we will hope.

Most record setting walks have numerous highlights. In addition to the mountain chickadee, Darren picked up a hermit thrush perched quietly in Morrisroe's garden. We also got a dark-eyed junco and a flock of cedar waxwings. Both dark-eyed juncos and hermit thrushes make tempting bird of the week targets. However, rather than talk about another highlight bird that we saw, I wanted to mention a Cardueline "finch" that we didn't see, the pine siskin. These birds are closely related to lesser and American goldfinches. They are also resident in parts of southern California but we haven't seen one on the Caltech bird walk since 2003. Last week, Darren mentioned that an eruption of pine siskins may be occurring. Usually, these eruptions begin in the Fall with dispersal of juveniles looking for new habitat but the effect is most clearly felt in the winter because you will see a species in an area where you don't normally see them. The term "eruption" is usually reserved for a regionally significant event but local "eruptions" can also occur. Our chickadees of the last year and a half probably reflect a local "eruption" derived from the Station fire. It is likely that our bumper crop of nuthatches this year reflects a local "eruption". For pine siskins, a state level eruption of some sort occurs once every two or three years, as the regional pine cone crop waxes and wanes, so the simple explanation for pine siskin eruptions comes in three words: feast and famine and density. A big seed crop leads to more fledged birds and greater survival rates over the winter. If, in the following year, seed crop yields are poor and the population density high, you can get an eruption as the birds seek out new habitat (or starve). Based on sightings between 1988 and 2003, we are entering prime time for a possible Caltech sighting of pine siskins as the bulk of our sightings are between weeks 49 and week 7 and most were between weeks 49 and 3 (i.e., December and January). However, keep in mind that pine siskins are not a species we normally see. Overall, you might reasonably expect that our sightings would correlate with eruption years in California and this appears to be the case to zeroth order but there are some issues. We have a total of 26 pine siskin sightings on the Caltech bird walk concentrated in seven individual years with no sightings after 2003 and all but one before February of 1997. Five of the seven years occurred when there was a major eruption for the entire state but the most prolific year, 1992, was a stay at home year for pine siskins at the state level. Moreover, eruption years after 2003 didn't come with pine siskin sightings at Caltech. It's unclear how far away Caltech pine siskins come from but, if they are relatively local, this suggests that either our local population isn't healthy or we aren't supplying the right kinds of winter seed.

The date: 11/26/2012
The week number: 48
The walk number: 1171
The weather: 66 F, sunny

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

The birds (25):

Scrub Jay
Northern Mockingbird
Mourning Dove
House Finch
Anna's Hummingbird
American Crow
Mallard
Yellow-rumped Warbler
European Starling
Black Phoebe
Lesser Goldfinch
House Wren
Ruby-crowned Kinglet
Common Raven
American Goldfinch
California Towhee
Hummingbird, Selasphorus
Bewick's Wren
Red-tailed Hawk
Hermit Thrush
Warbler, species (not yellow rumped)
Bushtit
Mountain Chickadee
Dark-eyed Junco
Cedar Waxwing

--- John Beckett

Respectfully submitted,
Alan Cummings
12/20/12

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






11/19/12

The snowy egret is gone and we didn't see a raven but we did have a Darren sighting. The beginning portion of the walk was also stellar. By the time we got to Tournament Park, we had 16 species. However, the last two thirds of the walk was not nearly as productive. Our final species total of 19 ended well above the minimum of 11 and just ahead of the median of 18 (i.e., we had a positive score) but it was significantly shy of the record 22 set last year.

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

Darren picked up the alarm call of an American robin in the Maintenance yard and we soon had two or three of these birds succumbing to solid visuals. That was a highlight. We haven't seen a scrub jay for a while, so that's a bit of a highlight, too. However, since I talked about lesser goldfinches last week, I thought it appropriate to instead consider American goldfinches in this report. If you look at Alan's probability plot for this species, you would conclude that these birds are basically winter visitors for us with nearly all sightings between weeks 40 and 15 with some dribbling on the Fall end into August and September, weeks 31-39 and out as far as week 19 (early May) in the Spring. Even this distribution is a little misleading because all of the sightings between weeks 31 and 38 came from one of three years (1994, 1996, and 1997). Clearly, American goldfinches don't much like us during the breeding season, which is visually unfortunate because that's when the males have that canary yellow and black contrasting plumage. It's not a matter of the goldfinches flying off to Alaska because, except in the northern end of their range, American goldfinches are only short distance migrators. They do breed locally. However, American goldfinches like riparian/marshy environments much more than lesser goldfinches (or Lawrence's for that matter) and, in the Spring, once it starts getting dry around campus, the Americans leave us. This is likely why the summer finch niche of Caltech that has opened up in the last decade has been filled by house finches and lesser goldfinches and not by American goldfinches.

Ask somebody what a bird can do better than a human unaided by technological baubles and you will likely get the response, "birds can fly." That is a pretty cute trick but it just scratches the surface. It's other general traits and the exceptions that I find more sobering. So, let's level the playing field and compare flightless birds with flightless humans. Take swimming. Your average bird is a very weak swimmer and our pools are killers of birds (also killers of young children) because of this - in the last 15 years, my pool has killed, I am sad to say, an orange crowned warbler, who must have gotten too close to the water chasing an insect, and a just fledged crow; thankfully, no children). Those of us who can swim would get across that pool, even normalized to body length, faster than a typical passerine. However, a flightless water specialist like an Adelie penguin can average 5 miles per hour over hundreds of miles; the very best we can do after decades of trying very hard is 5 miles per hour over 50 meters and, even that only comes through cheating (goggles, swim trunks, shaving of body hair, a "flying" start, and a body length three times that of our Adelie). "Ah well," you say. "We aren't actually designed for swimming, even if we are in the end modified fish, and it's actually amazing that we do as well as we do. We are designed for running and almost any of us could take that Adelie in a fair foot race." Now, the Adelie might actually take you up on that bet because the fair foot race would logically take place on packed snow at -40 degrees C. Oh, and, by the way, you don't get to wear anything, not even goggles. Now, I will accept, for the sake of argument, the possibility that you might beat the Adelie and uphold the honor of humanity before you froze to death but I have to note that, if our Adelie had a smart agent, which we must assume, the required distance would turn you into a frozen popsickle and the Adelie wins. So, let's try for some pure speed under more mutually comfortable conditions. You will, of course, put up Usain Bolt, currently the fleetest of us all. He tops out at 28 miles per hour sustained over 20 meters with an average stride length of 8 feet (and he can't do it every day). A run of the mill ostrich can hit 40 miles per hour with a 10 - 16 foot stride length; he would make Usain Bolt eat dirt. Now, I admit that we could probably beat that ostrich in a long distance (say, a 24 hour) race. I think, that's reaching for straws but I will cede the point. By my count, that makes it Birds 1 Humans 0 for flying; Birds 2, Humans 0 for swimming; Birds 3, Humans 0 for sprints and Birds 3 Humans 1 for long distance running.

OK, let's take some equally important but perhaps less obvious skills. I've mentioned previously that many birds have the ability to detect magnetic field strengths (Birds 4, Humans 1). They can also see as well as we do towards the IR (let's say a draw) but also well into the UV, where we are completely blind (Birds 5 Humans 1 Draws 1). Birds can also claim an ability to detect variations in barometric pressure. Exactly how they do this is still highly controversial but a flock of American goldfinches on the cusp of sharply dropping barometric pressure knows with deadly certainty that a big storm is coming and they will eat voraciously the day before it arrives. Why? It costs energy to maintain body heat in the face of cold windy weather. An American goldfinch who doesn't stock up and then doesn't eat for a couple of days because there are no foraging opportunities will be a dead American goldfinch. This capability is almost certainly better than granddad's old bones acting up before the storm and I am awarding a point to the birds (Birds 6 Humans 1 Draws 1).

A probably related skill set is the ability of birds to fly at a constant altitude even if they can't see the ground or the horizon (many birds are nocturnal migrators) but I will pretend that this is part of flying and not a legitimate point of comparison. Singing? When the very best of us (Mozart) walks into pet shop and hears a European starling singing, his response is "Das War Schon!" or "That was beautiful!" He immediately buys the bird and becomes so attached that when it died three years later, he gave it a human quality funeral. Who influenced whom? Starlings are half decent mimics and, I am sure that Mozart's starling picked up some phrases from Amadeus. As a counterpoint, however, listen to the beginning of the last movement of Mozart's Piano Concerto in G major, K. 453. That's Mozart's starling. Some people have argued that "A Musical Joke", K.522, which was the first piece of music Mozart produced after the deaths of his father and the starling, is all starling inspired. However, in the end, the real problem with judging music is that it is highly subjective, a matter of taste; I am not quite sure that our judging panel consisting of equal numbers of birds and humans would deadlock because the odd human judge might, in fact, vote for a bird but, I will give the benefit of the doubt to humans and, in honor of Mozart, offer a draw. I'm quite confident that humans couldn't possibly win. I just don't see our female white crowned sparrow judge swooning over an Adele song. So, it's Birds 6, Humans 1, Draws 2.

For our tenth and last contest, I offer an IQ test. Here, the raw numbers would favor humans over corvids, the avian representatives, although humans seem to do a lot of clever manipulations of environment either without a consideration of the consequences or ignoring likely outcomes. Smart on the front end and stupid on the back end. That's us. Nevertheless, it's a late win for the humans and a final score of Birds 6, Humans 2, Draws 2. Better luck next year!

The date: 11/19/2012
The week number: 47
The walk number: 1170
The weather: 67 F, partly cloudy

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

The birds (19):

Scrub Jay
Northern Mockingbird
Mourning Dove
House Finch
Anna's Hummingbird
Acorn Woodpecker
American Crow
Red-tailed Hawk
Mallard
Gull, species
European Starling
Bushtit
Yellow-rumped Warbler
Lesser Goldfinch
Ruby-crowned Kinglet
American Goldfinch
Hummingbird, Selasphorus
Black Phoebe
American Robin

--- John Beckett

Respectfully submitted,
Alan Cummings
12/18/12

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






11/12/12

This was a less shaky walk than last week's. We only made it to 15 species, just one better than last week, but got we an unambiguous crow and although the species count was light, there were generally multiple examples of each species to work with. We weren't flirting with an under double digit disaster. In fact, we weren't that far off a record. We were far above the worst total for the week (six), a healthy three above the median, and only two birds shy of the record high.

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

This week, we picked up another Townsend's warbler, which I would have to say is the highlight of the walk. It's our second Townsend's of the season. Alan first saw it in a gum tree on the east side of Wilson Avenue, near Braun. The bird cavorted around a couple of trees, yielding identification quality views. Then, perhaps thinking that this was an insufficient exhibition, our bird flew across the street and landed right in front of me, in a tree outside the Wilson parking structure. I got an excellent view. This is, hopefully, the same bird we saw a couple of weeks ago in the sycamore north of Braun because that would suggest a campus resident for the winter. Historically, being defined for me as the couple of years that I have been on the walk, Townsends have generally been sighted in the Maintenance yard or in Tournament Park; they were often seen in the oak tree cluster near the restrooms (along with black throated gray warblers). This year, we have yet to see a black-throated gray warbler and the Townsends have been eerily absent from the southern end of campus. This could mean a variety of things. Our recent burgeoning of Townsend/black-throated gray sightings could have been a reflection of the Station fire and that pulse is now subsiding. Perhaps, clear cutting on Victoria Island and/or the Queen Charlotte Islands, which are where our Townsend's are coming from (and going to) is creating an ecological trap for the warblers because they love the forest/clearing interface and its bountiful food supply but predator losses lead to fewer fledged birds. Perhaps, their losses on migration have been increasing. Perhaps, there has been a shift in insect population in the Tournament Park oak stand, making it less appealing. Incidentally, the Queen Charlotte Islands are now, officially, Haida Gwaii. You should google the Haida Gwaii reconciliation act for an interesting and potentially important example of natural resources management that may, in the long run, benefit Townsend's warblers but time will tell whether or not it works.

There is a trembling force to a pillar falling. It can craze the air and hollow your life. It can cause the unspoken to rise like the shadow of a whale breaching, even if you didn't know it was there. Sometimes, it comes in the form of a favored recent author. You come to a last book and realize there won't be another because the author is dead (like Kenneth Roberts for me) or has stopped writing (like Salinger). The first time I encountered something like this outside a literary framework was when Warren Rudman, my favorite U.S. senator, announced that he was retiring from the senate. He wasn't dying (he died earlier this year) but it was a career change. I felt like I was being stabbed. It struck me as a great and depressing loss because, as long as he was in the senate, some subconscious part of me knew that there was at least one senator in Washington acting in the interests of the institution, the people of New Hampshire, and the people of the country. He was coherent, well informed, willing to explain, and not prone to spouting garbage, demagoguery, or knowing obfuscations, all part of the daily lifeblood of the average senator. There may have been a handful of others like him at the time but surely not a dozen and, definitely, nothing remotely close to a majority or even a filibuster capable minority. So, his leaving was a funeral and large part of that was not realizing how much I was subconsciously depending on his presence. In birding, the only place I've felt a similar shock was when I discovered that the ornithologist Louis Baptista had died (derived from a heart attack suffered while feeding birds in Golden State Park with a final collapse while tending a wild barn owl at his home). I had been running across his papers for some time. They invariably feel young and infectious with a brightness that I find compelling, even though a Baptista paper is rarely of use to me in writing up walk reports (he was a major force in our understanding of white crowned sparrows). So, why, you might reasonably ask, should any of us, other than a blood relative, care about Louis Baptista? The answer lies in the languages of birds and the nature of science; I start with an anecdote about his childhood taken from an interview quoted in an obituary:

''In Hong Kong, the top floor of teahouses was reserved for bird lovers,'' he told a reporter for The New York Times in April. ''You brought your caged birds and drank tea and enjoyed their songs. My father would take me and I loved it. Also, my brother and I would often go to the countryside near where we lived to watch the wild birds. So when I came to this country in the early 1960's and learned that there was such a thing as ornithology, I thought, 'Good Lord, you can actually be paid to go out, watch birds and study their songs.''

So, Baptista followed his childhood and became an ornithologist. He was at Occidental College in the late 70s (i.e., local) and, at the time of his death in 2000, with the California Academy of Sciences at Golden Gate Park in San Francisco. He is important within birding because he helped us, I think more than anyone else in the last half century, to develop an appreciation for dialects within bird communities, the preference of some females for handsome males with elegant foreign accents, and the natural history of song development within birds. He was way beyond identity. He was like a birding Rudman for me. I had been coming across and reading his papers every now and then. The scientist part of me could feel that this was one of those extremely rare scientists with the insight and intuitive ability to find a path to a "why" as opposed to the "what" that most of us pursue. I mean this with no disrespect but there isn't another ornithologist in my reading who strikes me this way (maybe Grinell had some of it). I like Zink papers and those by others doing DNA studies on birds but these are a simple applications from a field developed by others. They are not pointing out a new "why". A subconscious part of me must also have felt that it was a good thing that we had somebody like Baptista out there writing papers about how birds learn to sing. Finding that Louis Baptista wasn't doing it anymore came to me as a stab.

The date: 11/12/2012
The week number: 46
The walk number: 1169
The weather: 70 F, sunny

The walkers: Alan Cummings, Vicky Brennan, John Beckett

The birds (15):

Mourning Dove
House Finch
Anna's Hummingbird
Acorn Woodpecker
American Crow
Yellow-rumped Warbler
Mallard
Lesser Goldfinch
Nuttall's Woodpecker
Ruby-crowned Kinglet
Black Phoebe
Townsend's Warbler
Red-tailed Hawk
Snowy Egret
Bushtit

--- John Beckett

Respectfully submitted,
Alan Cummings
12/11/12

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





11/5/12

Well, what a difference seven days and eleven degrees can make. Last week we were buzzing with interesting birds. This week, we found ourselves struggling to make a double digit species count. Last week, we had a rather pleasant 82 degrees. This week, we breached at 93. Usually, this is a recipe for no Vicky but this time, she still came. The birds, however, had other ideas. They were largely sessile and unusually quiet. This is not how a Fall day is supposed to go. By the time we rounded onto Wilson Ave., we were still mired in single digits. The end of the walk saw us at 13, a weak showing befitting the conditions. The total bumped up by one when Alan and I picked up a very bad view of a wren in the bushes next to one of the Throop ponds but that was far as we could take the day. We were safely ahead of the low for week 45 but not much more than half way to the record of 24 set just last year and even below the median of 17. Hopefully, next week will have a better offering.

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

Alan is usually open to whatever comes but, today, he is tinged in overconfidence. He recognizes the heat but this is a genuine Fall day. How could we not see lots of birds and many species? The overconfidence is manifested almost immediately. You are allowed to bring birds you encounter on your way to the starting point of the walk and I have two to offer. My first bird is a mallard that I had picked up at the Throop ponds. My lunch duck makes an immediate impression on Alan's list. He scribbles down the name and then looks up expectantly. I take in a breath and breathe out with a "corvid species". This was founded on a distant call. I was reasonably sure it was a raven, certainly more likely than not. I could probably have talked those baritone bubbles into two or three to one odds but the standard is 90% certainty. I couldn't go there and my offering was met with the closest thing I have ever seen to a sneer from Alan. He was not going to waste his time writing down such a silly ambiguity. A crow or a raven was bound to show up somewhere along the walk route. So, my bird was left to fester until somewhere late in the walk, a reluctant scratchy scrawl slinks across the page: "corvid, sp." It was a sign of desperate times.

Not only did we not have a lot of species on this walk, there were also no obviously stellar birds, whether by virtue or rarity. Birds were both scarce and reluctant. So what do you do if there are no unusual birds to be had in a walk? You take the opportunity to discuss a "common" bird and, this week it is the lesser goldfinch that rises to bait. If you only consider sightings over the last couple of years, you would conclude that these birds are so common on campus that it is far easier to list the weeks we don't see one than the weeks we do. True enough but the observation comes with a caveat of when. For this year, three walks, so far, were devoid of lesser goldfinches. Last year it was only one. In 1989, however, we didn't see any lesser goldfinches at all and before 2002, it was never more than eight sightings a year. It was nine in 2002, 10-12 in 2003 - 2005, 18 in 2006, 34 in 2007, 45 in 2009 and 47-51 since. So, what happened? If you look at the pattern of sightings prior to 2003, you will see rare sightings in August (roughly weeks 31-35) with a sharp upward pulse of sightings in weeks 37-41, dropping into the last part of the year, rising with the new year to a peak around weeks 5-8 with nothing between weeks 12 and 31. This sounds like a major migratory signature (peaks in September and February/March with some juvenile dispersal sightings in August and the odd winter visitation). In 2003, however, the pattern abruptly changed with sightings in weeks 17, 20, 27, and 28, all within what had been an empty abyss for goldfinch sightings. We had two to four of these odd period sightings in each of 2004-2005, which pretty much accounts for the observed increase in sightings relative to the 1980s and 90s. It appears that we had a small breeding population establishing itself on or near campus. Since winter sightings were arriving at the same rate, these new birds were apparently not wintering on campus, no doubt a sign that we were offering a poor palette of winter food for goldfinches. In 2006-2008, we picked up progressively more summer sightings but the winter sightings rate also increased, so our lesser goldfinches were not only breeding here in increasing numbers but they were also staying through the winter. By 2009, the species had become endemic from day to day and a year-round resident.

In the beginning, we are all wizards in a baby's babbling or a three year old bubbling down the aisle turning berries into pears. Why does he do that? Because he likes the word chartreuse and can only use it for a king of yellow green or heavy drinking in a mother's nightmare sweating out at three in the morning. Oh, this is a serious business, this magic of berry pears. You change a name and you change a I or a you. We change a bird into a bee or a house finch into a hoary redpoll. Even in a shopping cart, you can talk to dragons or tilt your head to savor ceiling tiles and splotches oozing bugs and worms. Your mother doesn't need to know how or why because there are many images in one true name, just as there are many names for a single image. The problem is that once we think we know, we forget to create. That's the danger in a name. On the Caltech bird walk, we generally seek a bird of the moment through a common name but this is tied to a scientific name that is supposed to underlie the cozening given every birder by a bird. We throw a lot of names around but what do they really indicate? Do we know the true names? Take our lesser goldfinches. If you had asked about them a few years ago, you would most likely have heard the supposedly magical words Cardeulis psaltria, which spoke to a close relationship (i.e., same genus) with other goldfinches, siskins and redpolls. It sounds nice. It's sounds scientific but it is also wrong. In 2008, an extensive DNA study of the then genus Cardeulis showed such a mess that a year later (see the 50th supplement to AOU check-list) there were three newly minted genera in a place that had required only one. Redpolls are out (genus Acanthis). Lesser goldfinches, now Spinus psaltria, are still kissing pine siskins but, if we listen to their swooping calls and expect them to talk to us now that we know their true names, again, we are sailing a discomfiting dream. Lesser goldfinches are still Cardeuline finches, because Cardeulis is a subfamily that still contains them, but our little labels, however useful as sterile pigeonholes, capture a bird like a sieve captures water.

The date: 11/05/2012
The week number: 45
The walk number: 1168
The weather: 93 F, sunny

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

The birds (14):

Mourning Dove
House Finch
Anna's Hummingbird
Acorn Woodpecker
Mallard
Yellow-rumped Warbler
Ruby-crowned Kinglet
Black Phoebe
Lesser Goldfinch
Bushtit
Corvid, species
Orange-crowned warbler
Hummingbird, Selasphorus
Wren, species

--- John Beckett

Respectfully submitted,
Alan Cummings
12/7/12

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





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