City Creek Nature Notes – Salt Lake City

June 23, 2017

June 20th

Summer

First Day of Summer

External Link to Image

Comparison of City Creek Canyon Road near Mile 1.1 in Winter on November 24th and on the First Day of Summer, June 20th.

6:00 p.m. It is nearly 100 degrees Fahrenheit on this first day of summer. Although this is the longest day of the year, and the amount of total light is four times the amount of light that occurs on the winter solstice (March 21st), this is usually not the hottest day of the year. The Earth continues to absorb the sun’s heat by melting at the poles, and thus, the hottest days of the year with 100 plus degrees Fahrenheit are lagged by three or four weeks to the end of July. But the recent heat wave is an unusual preview of the coming summer hottest days. Today, and more typical of late July, the heat boils the water from the land, and in the afternoon, great cumulus clouds rise and re-deposit the day’s water during the cool of the evening. As I approach the canyon, the sky to the west is gray and boiling. The bottom of the cloud layer swirls in confused eddies and circles. Winds rage and the trees wave back and forth as if they are in a current below the surface of the ocean. Only the large Common whitetail dragonflies (Libellula lydia) hover in the strong breeze. The whitetail’s are misnamed; their tails are more often black. From the safety of the leaf screened branches, Song sparrows, Chirping sparrows and Black-headed grosbeaks call. First, the air smells of summer, but then it mixes with the rain primed, fresh moisture. Small spatters fall, and then a brief deluge comes. Runners on the road, including myself, jog without their shirts on. The afternoon storm passes, the air clears, and all is renewed.

Along the first mile road, Milkweed plants have grown large, fecund seed heads.

* * * *

Although Thoreau declares summer to begin informally on June 1st (see his “Journal” on June 1st, 1853), astronomically summer begins on June 20th. Per Thoreau’s “Journal” on June 20th, 1840, he sees mica particles glittering in sand. On June 20th, 1852, he notes blue-eyed grass flowers are closed in the before sunset, and he hears an American Bittern drumming on wood. He notes that grass fields are red tinged because the grass has gone to seed. On June 20th, 1853, he sees meadow-sweet flower and water lilies. During a full Moon walk, he admires how water reflects black under moonlight. He encounters a skunk. He notes that elm leaves and trunks have the same hue under moonlight.

* * * *

On June 20th, 2011, the Salt Lake Tribune published a historical article on George Ottinger, founder of Salt Lake’s fire department and later in the early 1900s, Salt Lake City’s Superintendent of Waterworks. He lived in an adobe house on 3rd Avenue and E Street. As a young man, Ottinger was an adventurer. He traveled as a sailor to China, Hawaii, the Indonesian Islands, and Panama, before returning for a late California Gold Rush (id). Omitted from this article is Ottinger’s witnessing of the last 1887 lynching of a man in downtown Salt Lake City. On June 20th, 1999, Utah Jazz assistant coach Mark McKown was injured while speeding down City Creek Canyon a bicycle (Salt Lake Tribune). He was accompanied by Utah Jazz star basketball player Karl Malone. On June 20th, 1998, City Creek Canyon was closed for three days after torrential rains caused a mudslide (Salt Lake Tribune). On June 20th, 1908, City Engineer L.C. Kesley budgeted 9,000 USD to extend an iron pipeline from State Street to City Creek Canyon Road and 50,000 USD for a distributing reservoir in City Creek (Salt Lake Herald). On June 20th, 1896, ore samples taken from the Willard Weihe claim in the Washington mine group, 1.5 miles north of Eagle Gate in City Creek Canyon, assayed at 94 and 84 USD per ton (Salt Lake Herald).

June 13, 2017

June 4th

End of the Snowmelt

7:00 p.m. Temperatures reach 97 degrees today; one degree short of a record. As a consequence, the SNOTEL station at Louis Meadows records that all of the snowpack at near mile 7.0 of the canyon is gone. This is a seasonal milestone, and from now to next October 1st, the stream will flow only from rainfall and water stored underground. This afternoon, clouds stream in from the west, but it is too hot for the rain, which falls in curtains from a thousand feet overhead, to reach the ground.

Birds are quiet in this later evening, but still a single Blacked-head grosbeak is seen and heard near mile 0.2. A single House sparrow and a Chirping sparrow are also heard along the first mile road. Later, returning down canyon, I am for the first time able to see and hear the grosbeak performing a call with three low notes followed by a trill. This is a common call heard in the first canyon mile, but it does not appear in my reference recordings for this grosbeak. Other songs and calls for this grosbeak are in the reference recording. Butterflies are also subdued in the evening. There are single instances of a Mourning cloak, a Cabbage white and a Western tiger swallowtail. Gnats are rising in the heat.

* * * *

In Thoreau’s “Journal” on June 4th, 1852, he hears birds singing at dawn and he sees that dandelions have gone to seed. On June 4th, 1853, crickets are singing at noon. He examines oak and chokeberry leaves. On June 4th, 1855, white and red clover are blossoming, and mosquitoes are rising. On June 4th, 1857, he notes “earth-song,” or the combination of the sounds of insects and birds as a sign of summer. On June 4th, 1860, he notes elm trees are in full foliage, and that warblers have left for the season. Buttercups are in bloom. He sees a cat bird.

* * * *

How much water is stored in the east and west halves of the Salt Lake salient (may 14th) that drain into the stream? Using the difference between stream flow data taken at the canyon’s water treatment plant from 1950 to the present and precipitation records from the Louis Meadow SNOTEL station for 2000 to the present, I am able to make a rough estimate of the lower bound of stream flow that comes solely from underground reservoirs. For two months each year – June and July, average stream flow exceeds average precipitation. In June, the average stream flow exceeds rainfall by about 318 acre feet, and in July, the stream flow exceeds rain by about 242 acre feet, for a mean underground flow into the stream of 280 acre feet per month. This 280 acre feet per month is the lower bound. Summer rainfall will evaporate and never reach the stream or recharge underground aquifers. Depending on underground geologic structures, all of the water that falls within the 19.2 square miles of the canyon may not flow towards the stream. The oak and fir forests and grasses consume considerable quantities of rain water, and those withdrawals are not included in the sum of the difference between inflows and outflows. Thus, the true amount flowing into the stream from underground aquifers could be two or three times the lower bound of 280 acre feet per month. The 280 acre feet of water each month is enough to flood 28 of the city’s 10 acres blocks with a foot of water. The volume of that water is about 12.2 million cubic feet of water (0.000083 cubic miles), or a cube about 230 feet on a side. In contrast, the Mormon Temple that sits at the heart of City Creek Canyon’s delta (March 10th and March 12th) is 288 feet tall.

The lower bound of 280 acre feet of underground storage is a reasonable estimate. Treating the 12 miles of the Salt Lake Salient as two inward facing right-triangles that are 1.25 miles from the stream to ridgeline, the volume of the salient that drains towards the stream is about 32.5 cubic miles. The 0.000083 cubic miles of underground water flow is only 9 of 10,000,000ths of the salient’s volume. That water can easily fit in the pores space between the salient’s rocks.

* * * *

On June 4th, 1934, University of Utah Engineering Professor F. W. Muir reported that tree rings taken from City Creek Canyon and near Brighton show that in the last 300 years, there have been many drought cycles (Salt Lake Telegram). On June 4th, 1914, the City acquired 80 acres of private land in City Creek (Salt Lake Telegram). On June 4th, 1910, Land and Water Commissioner Frank Mathews reported that green caterpillars, possibly one million, are moving down City Creek Canyon defoliating (“stripping bare”) the trees (Salt Lake Telegram). On June 4th, 1906, streets in Salt Lake City principally from 300 West to 800 West, were severely flooded (Salt Lake Telegram).

June 2nd

Evolution of Angiosperms

8:00 a.m. Some days are beyond beauty. This is the first official day of the five months in which cars are allowed in the canyon on alternating days, and I have decided to drive up to the end of the road to jog the uppermost canyon. It rained last night, the undergrowth and trees are all covered with thick layer of drops. As I drive up the road, the morning birds are active. With the windows open, I mentally tabulate a count as I slowly travel up the winding road. It comes to about 20 birds within earshot for every quarter mile. This suggests a population of some 800 smaller song birds along the five and three-quarters of paved road and the subsequent 2 miles of trail in a band for 50 yards on either side of the road.

Continuing the drive up canyon, Wild roses are open to Pleasant Valley, mile 1.1, and Wild geraniums are open to mile 5.0. Along the first mile, a new flowering plant, another weed, has sprung up to two feet tall seemingly overnight. It is Western salisfy (Asteraceae tragopogon dupon). Although a noxious invader, it is an admirable plant. To avoid the heat of the day, it folds closed into a pen-like tip, but now in the light morning sun, it shows sixteen thin yellow petals surrounded by hair-thin sepals. The center has a sharply contrasting black band. It lines the roadside and at Pleasant Valley, Utah Conservation Corps treated field, that removed yellow starthistle, is now covered with another invasive – salsify. A purple variant of this plant is also found along the first mile road.

At the water treatment plant at mile 3.4, the canyon narrows, and flashes of blue and black flittering into the Gambel’s oaks reveals a flock of Stellar’s jays. Stellar’s jays prefer the coolness of a montane habitat, and in contrast, their cousins, the Scrub jay, prefers the hotter lower canyon. But the Stellar’s jay is more territorial, and thus, more entertaining. When a hiker enters their territory, one will immediately swoop down to the trail and call with its repetitive “caw” in both curiosity and in complaint. The action of one will others of its tribe, and this provides the walker with an avian presidio under which one must pass inspection. Later in the afternoon, further up the trail at the end of the road, as I walk under a large moss covered log, a Stellar’s jay lands above me, its mouth full of moss intended for use as nesting material. It glances back for a quick inquisitive look and then proceeds on its business.

Resuming the drive up the road and as the walls of the canyon close in, the canyon transitions from Gambel oak forest to deciduous maple and Box elder tree forest. The road becomes a single track. The heavy moisture on the leaves is heated by the first penetrating morning sun, and as a result, the air is thick with mist and dew. Shafts of light peak make it through the dense overgrowth and illuminate the mist into yellow tubes. Here, the canyon feels most like an eastern forest. Although the dense greenery only extends for a few hundred yards on either side of the road, the narrow canyon walls cut off any vistas, and this is what I remember of my boyhood eastern forests. The green goes on forever and the all sense of direction is lost. Here, stream bed widens and the stream slows. But then, near mile 4.5, there is an abrupt transition to a Rocky Mountain forest (Peet 2000) dominated by Douglas fir and Norway spruce. The stream narrows and the stream bed becomes boulders that are angular and freshly honed from bedrock. This change is also announced by great vertically upended limestone fins on the western wall of the canyon that have been turned by earthquake faults (Sept 1st). The Wild geraniums thin out, and the first Mountain bluebells, a cool weather plant, appear and become more frequent. The air thickens more and forest becomes medieval.

Along this stretch of road between Lower and Upper Rotary Park, the bird communities, mostly of American robins, Song sparrows, Warbling vireos, and Black-headed grosbeaks are spread out into distinct communities, unlike in the warmer first mile canyon. The distinct trill call of a community of Chirping sparrows is heard. I also hear a lone Mountain chickadee calling. This is where they have come, since the lower canyon is too hot for them. This segregation of birds into unique groups along the road gives me the opportunity to stop and study the distinct songs and calls of a group of Warbling vireos.

The sun rises further and the mist burns off as I reach the end of the road at mile 5.75, and the old mining road and trail that leads to the Treasure Box mine begins. I have not been here since the end of last summer (Sept. 8th), and it feels restorative to be in the most natural of the canyon’s regions. Leaving the car and proceeding up the trail, where the direct sun penetrates, a green canopy of maples and box elders closes in, while on shaded eastern slope, Douglas firs reach to trails edge. The air is heavy with the smell of wet leaves and chlorophyll. Crossing the first and second red metal bridges affords views up the stream, and it is a torrent of white, with only hints of blue water. The stream has become a silver ribbon. After the third metal bridge, the trail rises, the canopy deepens and the undergrowth becomes impenetrable. This stretch is as the lower canyon appeared around 1900. Shipler’s photograph of the lower canyon road taken around 1903, appears nearly identical to this morning’s rise in the trail (J. Willard Marriott, Id. 459448, see also Salt Lake Tribune, May 24, 1903). The chirping call of a Green-tailed towhee is heard.

For the next half-mile, the trail is about 150 feet east of stream, and the trail consists of sharp rocks that a month ago were another snow-feed branch of the stream. Geraniums and blue bells thicken along with young stinging nettle plants. All are so covered with last night’s rain water that my shoes quickly become soaked, but I do not care. A Mourning cloak butterfly with an odd color variant flies down canyon. Instead of the yellow-white trailing band, its trailing wing band is a dusky orange. Other now common butterflies appear uniformly distributed along the trail: Western tiger swallowtails and newly-hatched smaller Spring azure butterfly butterflies. The Spring azures flock in groups of three to six, and the harsh high-altitude light brings out a new property to their colors. Depending on the sun angle, their wings flash a deep medium blue, their streaked light blue, or flat light blue. The deep blue is new variation to their iridescence. There is a new unidentified one and one-half inch butterfly. It has forewings of patterned medium dark grey and rear-wings that are a grayish black. The colder air at this high altitude, along with their lack of exposure to humans, make insects sluggish. In the lower canyon, the Red-rumped central worker bumble bees are skittish. But here, the bees remain still when approached, and I am able to take a clear pictures of several.

Song sparrows, Warbling vireos, a Spotted towhee, Yellow warblers, and Lazuli buntings, another refugee from the lower canyons, are heard in profusion. But again, they rest in distinct communities in the spacious upper reaches of the canyon instead of being distributed uniformly along the trail. Jogging uphill feels good for the legs, but my progress is slow. I cannot resist the urge to stop and listen to each community of bird and to playback stock recordings of their calls, in part to assure to identification, and in part for the simple enjoyment of somehow communicating with them. At one point, the land between trail and stream widens, but is particularly lush with a low canopy. There I hear a single American dipper, the first of the season.

For the next half mile, the trail begins to narrow travels next to the stream, and the trail crosses a series of rock outcrops. There the trail becomes broken rock interspersed with patches of stream feed marsh, and the stream water itself is so pure that individual rocks can be seen distinctly on the stream’s bottom. A few Spearleaf scorpionweeds (Phacelia hastata) that have delicate light purple, fuzzy blossoms, hide in sun sheltered spaces. Along the broken rocks, I notice the small, 5 millimeter, dried-out shells of snails covering the trail. Over a 100 feet of trail, I count about the same number of shells. On picking one up and to my astonishment, there is a miniature live snail in each shell. I am unable to identify them.

Next, the trail starts to rise towards the first of four hanging meadows, and in the first of which stills with Louis Meadows SNOTEL weather station. Aspen trees first appear, a sure sign of a Rocky Mountain meadow ahead. Mountain bluebells surround the trail on both sides, and a few Western blue elderberry trees (Sambucus nigra ssp. cerulea) rise from the surrounding bluebells. Each elderberry is heavily festooned with white, lacey panicles. In the autumn, as their dark fruit ripens, these are a favored trail snack.

As I crest the lip of Louis Meadows hanging valley, the SNOTEL station comes into view. It sits in the middle of field of Mountain bluebells the size of two football fields, and the field is surrounded by a grove of waving aspen trees to the west and Douglas firs to the east. It is an idyllic sight; one that I feel privileged to experience. I begin to feel giddy and overwhelmed by biophilia.

While my heart feels love, my intellect says my expansive feelings are not the effect of altitude at just 6,700 feet (2,042 meters), but of ultra-violet radiation. The 10 a.m. summer Sun is high in the sky, and its warmth penetrates all clothing. The exercise of hiking in Western summer mountains is a relaxing experience. The cool air makes hard, fast hiking enjoyable, but at the same time ultra-violet relaxes the muscles and the mind. Pictures taken here today all are blue tinged from the uv light. With every 1000 meters in altitude, uv light increases in intensity by 10 percent. An internet uv intensity calculator suggests this morning’s ultra-violet index is 12.

As I nearly reach the trailhead and the car, the only other hiker in the canyon today, a young man in his twenties, overtakes me, and he can only mutter, “That is so unbelievably beautiful!” as he passes by. Words escape us both. We have been closer to creation and the other world of the upper canyons of the Wasatch Mountain Range.

Driving out the lower canyon and back to that other reality of my human social and economic existence, the Mosquito Abatement District surveyors are examining their blue painted tree holes (November 7th). They are taking a census in order to estimate the canyon’s mosquito population.

* * * *

In Thoreau’s “Journal” on June 2nd, 1853, he travels through a thick fog and notes that birds are still making song. He sees cherry birds and yellow bluebead lily, an eastern plant, and red sorrel. On June 2nd, 1855, he describes a moth cocoon opening. On June 2nd, 1858, on a camping trip to a mountain top, he examines a snow bird nest, and hears a chewink, a wood-thrush, and night-hawks. On June 2nd, 1859, he finds a grossbeak nest in a blueberry bush. On June 2nd, 1860, he sees bats and a king-bird.

* * * *

Fully preserved angiosperms first appear in the fossil record about 130 million years ago and by 90 million years ago, flowering trees had dominated the forest canopy. Pamela and Douglas Soltis at the University of Washington with Mark Chase at the Royal Botanical Gardens used modern gene mapping to reconstruct the evolutionary phylogenetic clades of flowering plants (Soltis, Soltis and Chase 1999). Soltis and Soltis review state-of-the-art flowering plant clades as of 2004 (Soltis and Soltis 2004).

Magallon and Sanderson at the University of California at Davis used the rate of diversification of woody plants in the fossil record to estimate the age of the major families (Magallon and Sanderson 2001, Fig. 4). Members of the Sapindales family, which includes maples seen in the canyon, appeared about 60 million years ago. The Rosaceae family members in the canyon, which include Western serviceberry, apple trees, chokeberry, ash trees, and Woods rose, evolved relatively recently, about 45 million years ago (id). Modern oaks appear about 35 million years ago. In Utah around 35 million years ago, the Farallon Plate had passed through Utah, crustal spreading behind the plate cracked Utah’s surface, and the spreading generated Utah’s volcanic era (January 7th). The volcanic breccia at milepost 1.0 of the canyon was forming (id).

* * * *

On June 2nd, 2002, teenager Elizabeth Smart was kidnapped from her Federal Heights home and was hidden on the south slope city side slope of the Black Mountain-City Creek ridge for two months (Salt Lake Tribune, March 15, 2003). The hiding place was not found by a 2,000 person search organized by the Laura Recovery Center (id). On June 2nd, 1915, the City Commission approved plans to build a 5,000,000 gallon reservoir at Pleasant Valley (Salt Lake Herald). On Decoration Day (May 30), a picnic was held in City Creek as reported on the social page of the Deseret Evening News.

May 9, 2017

May 6th

Wizards of the Canyon Soundscape

7:00 a.m. The entrance to the canyon along Bonneville Drive is closed today for one of the many social 5K runs that occur during the summer. This adds an extra mile jogging along the drive to reach Guardhouse Gate. As I start, the sun line is just beginning to descend the snow capped peaks of the western Qquirrh Mountains and the small sliver of the southern tip of the Great Salt Lake reflects slate blue. The clear western sky shows the last vestiges of dark slate band of the Earth’s shadow retreating from the sun. Along the first stretch of road there are many sage brush bushes that provide cover to chukars. I stop to pick and crush a bracket of this pungent bush to remind myself of what Utah smells like during the heat of summer. About one-half mile from the gate and around a bend, the canyon explodes with the sounds of stream and birds. Although hidden, a male Lazuli bunting peaks from behind some red maple leaves, singing loudly. His colors are muted, since he perches in early morning shadow of the canyon’s east ridge. The sound of the stream is overwhelming, and this indicates the vernal season’s heat is melting the high snowpack. At the gate, the parking lot is full, and includes the enormous truck of the wild turkey bow hunter (May 4th). I must have just missed the race organizer’s closing of the road.

Along the road, the grasses are now twelve to eighteen inches thick, and the first quarter-mile is nearing full leaf out. Near mile 0.3, I look up through the trees to the step slope above, and there a young female mule deer idly grazes on the new grass. I stop to watch and after some minutes, she takes notice of me, stares back, and knowing that it is not hunting season and she is in no immediate danger, she slow walks and disappears into the Gambel’s oak forest. A bird loudly chirps from a nearby tree, and I catch a fleeting glance of black, white and red-brown from below. It is probably a Rufus-sided towhee (Pipilo maculatus). I count about forty or bird separate birds calling the forest thickets in the first mile.

I am not a morning person, most of my daily observations are in the afternoon, and the morning spring canyon is a new place. The warm morning light crawls down the western ridge of the canyon, and makes the thick grasses of spring bathed in an inviting green light. Although it is a pleasant high fifties along the road, one can feel the advancing daytime heat in the seventies approaching. Between mile 0.5 and 1.0, large overhanging trees in partial leaf-out form a series of green tubes through which the rising south-eastern sun penetrates. The lighted end of these tubes with the darkened green leafed foregrounds reminds me of the religious ceiling paintings of European cathedrals. I am overwhelmed by the beauty of it all.

In this half-lit morning reflected light, the canyon has a different character. I have misjudged the Starry solomon’s seal. In the afternoon, I have found two or three open out of an estimated 20,000 plants (May 4th). This morning, most are open, and I easily count 200 open blossoms in the solomon grove surrounding the seep below picnic site 5. The number of active birds is astounding, and a multiple of several times over my afternoon encounters.

At the entrance to Pleasant Valley, I run into the Tracey Aviary sponsored birding, a course directed by and led today by aviary biologists Bryant Olsen and Cooper Farr. I am happy to find the group; I have followed their Cornell birding logs in the canyon for some years; and in the spring, they regularly return to the canyon. Other seasons draw them to other habitats. Traveling down canyon, there seven group members including the leaders, and their five students are a diverse group that range from their thirties to eighties. They allow me to tag along as they proceed down the Pipeline Trail for the one mile walk back to the parking lot. Since I have been frustrated for some years in identifying the thicket hidden birds by sound, and I hope to gain some insight into the process by watching and learning. I quickly learn that I am in the presence of masters. Many birding skills quickly become apparent that explain the large number of birds that they record each week in the Cornell University E-bird log system (Cornell Ornithology Laboratory 2016).

First, birding in groups greatly increases detection. I first encountered this in amateur astronomy. Looking for detail in nature, which involves rare events, is more likely with more eyeballs that can cover the whole sky. In addition to the chance of making a sighting, the ability to perceive rare events also differs greatly by both the ability to perceive and by the knowledge to understand what one is seeing or hearing. The seven of the birders stare intently towards a sound coming from a clump of leaves, and one or two of the seven will first detect the bird, and then direct the others to it. Seven sets of eyes scanning the sky’s dome catch fleeting glances of bird movements in opposite directions, and this greatly increases the number of exclamations that one or another of some species has been seen.

Second, time explains the groups many sightings. As we descend the trail, younger runners and bikers wisk by at six to fifteen miles per hour. They traverse the mile of Pipeline trail in five to ten minutes. When I was younger, I has one of these. They smile as they pass, confident in their belief that in their superiority that their youthful ability to exercise makes them the most important denizens of the canyon. My slow jogging takes twenty minutes, but the birding group takes about one and one-half hours to walk this mile. Perception and time are inversely related. The slow see more; much more. Chance visual sightings reveal common sightings such as the cliff-soaring Red-tailed hawks. In this way, the group quickly seeings a Peregrine falcon resting on the top of the western massif at the entrance to Pleasant Valley and a brood of cliff dwelling Violet-green swallow (Tachycineta thalassina) living nearby in the crumbling deposits of Van Horn and Crittenden’s Triassic conglomerate No 2. sandstone. Are these the peregrine’s prey? Peregrines prey on many of the plentiful birds and mammals in the canyon, including mallads, swallows, Mourning doves, Northern flickers, starlings, American robins, Black-billed magpies, American crow, hummingbirds, owls, mice and Rock squirrels. Thoreau used the Peregrine’s historical name – the duck hawk – and Audubon memorialized this predator-prey relationship in a noted 1827 oil painting (Audubon 1827). The peregrines are in turn fed upon by larger birds of prey like Bald eagles and Red-tailed hawks. The birding group has great interest in following the falcon back to its nest, since these birds, although removed from the United States endangered species list in 1999, remain popular and are known to raise young near Pleasant Valley.

Third, these are the wizards of the canyon’s bird soundscape. Raw knowledge, expertise, and practice allows the group to identify many birds by sound alone or first by sound and then by sight. A member will hear a call of interest, and all will stop intently listening while leaning in one direction; some cup hands around their ears. Someone will call out a name, there is a discussion, and then a final determination is made as to the species. Sometimes, this is accompanied by a pointing figure and the exclamation “There it is!”, and all binoculars are raised in unison. I humbly learn the calls of one or two common canyon residents, like the chirping of the Rufus-sided towhee, and can notice distinct obvious sounds, like the wing-beat of a passing Broad-tailed hummingbird (Selasphorus platycercus) and the obnoxious squawking of the Red-breasted nuthatch (Sitta canadensis). But the group’s ability to identify unseen colorful birds by sound alone is astounding. They hear a Green tailed towhee (Pipilo chlorurus), an Orange-crowned warbler (Vermivora celata), and a Western tanager (Piranga ludoviciana).

The group’s ability is distinguish between similar calls is uncanny. I have a particular interest in the rapid chirping call of the Rufous towhee. Later at home, I compare audio recordings and spectrographs of several species found along the trail that all include to my uneducated ears, subtle variations on a series of four to six rapid fire trill chirps, preceded or followed by two tones. The songs of the Rufous-sided towhee, the Green-tailed towhee, and Orange-crowned warbler, are all variations on a theme.

The group continues down the trail as the bright line of sunlight engulfs them. The celebrity bird of the afternoon are many Lazuli buntings. On the western brightly lit slopes, perching on a Gambel’s oak, several of these buntings are seen. They males are aflame in their cloaks of brilliant iridescent blue. Bryant notes that a bird’s coloring are the result of their feathers refracting sunlight. The explains why colorful birds have dulled colors in diffused light, but radiant colors in full sun. Near trail mile 0.5, a Black-chinned hummingbird (Archilochus alexandri) sits on a powerline and obligingly ignores the birders as they take photographs. In the last third of trail mile, the sun and temperature has risen, the birds are less active, and the group quickly exits back to the road. A mallard rests in the flood retention pond.

I point out the cliff nest site that I followed last spring near mile 1.0 (Dec. 9th, 40°48.227 N, 111°52.204 W), but only about one-half of the group can see the nest. I had previously thought it was built by Peregrine falcons or Cooper’s hawks, but Bryant notes I am mistaken. Peregrines and Cooper’s hawks do not build stick nests, he says, a point supported in literature (Utah Legacy Raptor 2011). A later search on the internet returns many photographs of peregrines nesting in nearly identical stick nests. A probably resolution of the difference is found elsewhere: peregrine falcons sometimes will take over the stick nests of other raptors like eagles (White et al 2002).

Comparing the group’s Cornell Ornithology Lab birding logs for the canyon since April 30th reveals the arrival of many small migratory song birds with the abrupt rise in temperatures and the arrival of the vernal season (April 29th and May 1st). Common canyon birds in their logs in April through May 6th include mallards, European starlings, American robins, House finches, Song sparrows, Dark-eyed Juncos, Black-billed magpies, Mourning doves, Ravens, American crows, Red-tailed hawks, and Cooper’s hawks. New spring heat-seeking migrants that arrived just as the temperature switch tripped two or three days ago include the Peregrine falcons, Plumbeous vireo (Vireo plumbeus), Warbling vireo (Vireo gilvus), Orange-crowned warbler, Yellow warbler, Virginia’s warbler, Chipping sparrow (Spizella passerina), Green-tailed towhee, the Western tanager (Piranga ludoviciana), Broad-tailed hummingbird (Archilochus alexandri), Black-chinned hummingbird, Lazuli bunting, the Lesser Goldfinch (Spinus psaltria). These new colorful arrivals have followed the north running heat wave from the southern states and Mexico for a thousand miles to this northern canyon, and now that they have arrived, their next tasks will be mating and beginning the construction of nests.

I ask a question about what some of the most common canyon birds eat. I am interested in not only the simple phenological list of what bird species arrives when (this is what Thoreau did), but also how the web of insects, plants, and birds link together. The aviary experts’ answers are general and unsatisfying. “Seeds” (there are none), “grass” (they have not developed grains), and “insects” (there are still few, given the newly higher temperatures). The same vague discussions are found in my various paper and internet birding guides. I have witnessed a few instances in which canyon birds actually eating something over an entire year. A scrub jay ate acorns in the fall (Oct. 6th); wild turkeys ate winter acorns (Dec. 29th); chickadees ate winter fruit; spring kingfishers fish along the ponds and stream, although I have never seen them catch anything (March 19, April 6, 11, and 18); in the mallards eat spring algae from the stream; hummingbirds and dragonflies feasted on summer gnats (August 1st and August 11th), and a few days later, cliff swallows gorged on the dragonflies (August 22nd). In the spring of 2015, two falcons ate a mouse. But what are they, in particular the new arrivals, eating now? After this morning with the soundscape wizards and a subsequent literature search, I am struck both about how much science knows about the birds and how little science knows about birds. All things cannot be known, and I suspect there is little grant money available to fully construct and quantify the ecological relationships of even close natural areas, since minerals, logs, and skiers only have economic value and iridescent sheen of the Lazuli buntings do not.

A lone mallard sleeps near the shore of the flood retention pond. Jogging out of the canyon, the social-cause, 5k fun-run has begun, and three or four-hundred joggers are going towards milepost 0.5, along the opposite western leg along Bonneville Drive. A loudspeaker blares out popular music. Groups of racing bicyclists stopped by the police to allow the race to pass joke about blindly coming around a curve into such a mass of humanity. Their focus on life is different from mine, and neither, as they go about their respective enjoyment of the canyon, will perceive the dazzling blue of the Lazuli buntings seen by the wizards of the canyon soundscape.

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Iridescence in birds is caused by both pigments and the refracting structure of their feathers (Doucet and Meadows 2009; Rajchard 2009), and many birds also perceive light, including the iridescent refraction, in the ultra-violet spectrum (id). The view that humans see of birds is not what they see of each other. The blue feathers of birds, like the Lazuli bunting, may be hint that a bird can see ultra-violet light (see Doucet and Meadows, S118). Falcons use the ultra-violet reflection of mole and mouse urine to determine the density of their mammalian prey in fields (Rajchard). Fruit seeking birds like crows better see mature fruits because the ripe fruit better reflect ultra-violet light (id). Blue tits switch to the ultra-violet spectrum to see insects against non-contrasting backgrounds (id). The iridescent patches also help birds to distinguish their sexes, just as human birders do, but in some birds, the ultra-violet spectrum of their iridescent patches enhance the sex difference of their pigments seen in the human visual spectrum (id). Another study suggests that in the ultra-violet spectrum, some birds find it easier to distinguish eggs (id). Iridescence can also be an indicator of fitness to breed. Male birds lose iridescence as they age and when they are sick (Doucet and Meadows, S120-S121).

The iridescent patches of birds involve a trade-off. Iridescent patches, like those of the front-chin of the Broad-tailed Hummingbird and the side-neck of the Black-chinned hummingbird seen today, may be more visible to their predators, but they are also more visible to their potential mates (Doucet and Meadows). To reduce the predation cost of these patches, some patches are directional. A bird living in a diffusely, dark lit forest can perch in a ray of sunlight and send a narrow beam “flash” to other members of its own species and to potential mates (id). Predators circling above will not see this visual chatter. Conversely, the bright Lazuli bunting simply shines like a beacon. What do the hawks and falcons circling above see of these beautiful song birds in the shorter-bands of light that we human birders are unaware of?

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On May 6th, 1899, work to replace the City Creek water main with a larger diameter pipe was underway (Salt Lake Herald), although a suit seeking an injunction against the construction had been filed. On May 6th, 1888, Z. Jacobs canvassed citizens for suggestions on how to increase the city’s water supply, including Fire Chief Ottinger (Salt Lake Herald). Jacobs argued against building a dam in City Creek Canyon, since failure of the dam would destroy the downtown (id).

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