City Creek Nature Notes – Salt Lake City

July 30, 2017

July 21st, 2016 – End of Cyclical Year, Revised and Reposted

Microorganisms, Moss, Lichens, Glaciers, and Climate Trends

(Revised and expanded after lichen identification completed.)

3:30 p.m. It is another day intense summer heat, and as I pull into the parking lot, I take notice of a large Limber pine (Pinus flexilis at the lot’s end, south of the row of cultivar Horsechestnut trees. The Limber pine, Narrowleaf cottonwoods and the Horsechestnuts are among the largest plant organisms in the canyon, excepting some of the 50 foot diameter copses of Gambel’s oaks that may be one large, genetically identical sister plant. A bizarrely twisted, immature Limber pine hides behind to the east of side of the Guardhouse Gate building, and just past the gate, another conifer, a mature 70 foot tall native Engelmann spruce (Picea engelmannii). Key taxonomic differences between the two is that round pine needles occur in groups of two and flat fir and spruce needles are single. At mile 1.7 at picnic site no. 12. There a forty foot tall Rocky Mountain juniper (Juniperus scopulorum) is flanked by two taller Engelmann spruce trees. Although native to northern Utah, these three trees have been artificially planted to provide shade for picnic area.

Jogging up canyon about 100 yards up from the gate, I pass a deadly Bittersweet nightshade plant with small 1.5 inch green fruit. Splitting one of the fruit open, it is full of 1 mm bright orange larvae, and testing a few more, they are all infected. Given the number of young children that pass this spot, this is probably not a good place for a poisonous plant.

In the heat, I jog alone through an empty road, except for bicyclists. Near mile 0.3, sounds in the Gambel’s oak forest undergrowth betrays an yearling Mule deer stares back through the leaves. It is waiting for me to pass, so it can reach the stream and water. A bicyclist streaks unaware of its presence. A slight anabatic up-canyon wind provides a brief relief.

Beginning at mile 0.5 and the pond at picnic site 5, I collect the sponges placed in the stream and seeps on July 15th. The sponges have been collecting microorganisms for several days. I have looked at water samples from the stream under a microscope several times since May, but have never seen any microorganisms. That is a testament to how pure City Creek Canyon water is. My microorganism observing guide suggests using the sponges to trap organisms over time. The sponges also provide a protected framework that might appeal to microorganisms by providing shelter. The first sponge was located below the pond at picnic site 5, and it was placed under a cover of rocks such that stream water would continuously flow through the sponge. The first from the stream is a dark brown – a good sign. The second collected from the seep below picnic site 6 and the third is retrieved from the watercress seep also below picnic site 6. All three are a dark brown-grey color; the sponges have worked.

At the seep below picnic site 6, the Horsemint is in full bloom, and I count 32 Cabbage white butterflies feeding on them. A single Central bumble bee (Bombus centralis) collects among the butterflies. These are joined by an orange Mexican queen butterfly. I stand mesmerized by the glade for a few minutes. Nightshade is now also blooms in this glade.

Carpenter bee (Xylocopa californica) reappear after their first spring flight. Uniquely, they fly in a circular pattern closely around me twice, and having rejected me as potential food, they fly off with purposeful intent.

Proceeding again up canyon through the heat, only a few birds are heard at some distance from the stream. I cannot distinguish their calls, except for the nasal cawing of a Red-breasted Nuthatch (Sitta canadensis).

At mile 1.1, I stop where a large rock ledge overhangs the stream and admire a tremendous cottonwood cross, a Populus angustifolia x fremontii S. Wats. This 100 foot tree with a twenty-four inch trunk betrays it hybrid nature through two suckers, each 8 inches in diameter at the base. The parent tree has ovate leaves typical of the cross. Those leaf forms continue on one of the suckers, but at its very tip is one perfectly formed triangular Fremont popular leaf. Mid-way up the second sucker, that is also covered in hybrid leaves, is a bracket of perfectly formed thin Narrowleaf cottonwood leaves. This tree must be at least 100 years old, and perhaps it is older and witnessed the arrival of the Euro-American colonists in 1847. At a few minutes of enjoying this tree, I notice that it is looking back at me. More precisely, another Mule deer is on the rock ledge on the far side of the stream, and it is intently following me. I continue up canyon so it can reach water unmolested.

At mile 1.2, I turn down-canyon on the Pipeline Trial in order to photograph some of the lichens on rocks that line the trail down to where it is perpendicular to the Red Bridge and Chimney Rock. The Gambel’s oaks that border each side of the trail are covered in a ubiquitous dusky orange lichen that is found throughout the canyon. Here the rocks are principally volcanic breccia or limestone conglomerates. The first rock has lichens that are three inch diameter turquoise dollops with raised fruiting centers. The second rock has a large turquoise dollop on one corner and fire yellow bright lichen on one face. This rock also has small dark black lichen circles. The third rock has bright orange circles with darkened brown centers. The fourth has similar bright orange two inch dollops with fruiting orange centers. This same orange rock lichen is common in the canyon. For example, it covers parts of the rock bridge at Weeping Falls near mile 5.2. This bright orange lichen only appears on rocks, and its dusky orange brother keeps to the trees. Near the end of this segment, a gully provides more shade an water. Here, the rocks are covered in complex moss complexes, and unidentified green-black small-onion like moss with fine white hairs.

Continuing up canyon to a western gully near mile 2.3, there is another slope with favored lichen rocks. Here the rocks are sandstone based. In the gully, the first rock is a kaleidoscope of circular lichens colored bright orange, turquoise, and black. The next rock is covered with a bulbous green-black moss with fine white hairs. This is followed by a rock covered in turquoise-green lichen that has a darker brown center. Finally, two foot square areas of an unidentified green-black bulbous lichen attach to a rock ledge’s horizontal surface. Looking over some of my other lichen photographs above milepost 5.0, two prominent upturned limestone ledges stick out next to the road. On these a montane grey-milk lichen that look like delicate leaf petals cling to the stone.

This is all a riot of color mixed with abstract design. Lichen are oldest and, for me, they embody the most alien of terrestrial life. I also hold them in the highest respect because they are all a form of extremophile. They thrive on canyon rocks that both bake to temperatures over 150 degrees during the summer, and they continue to reproduce during the subzero cold of deepest winter. They live on the surface of barren rocks and take all that they need from the passing air and rain. And, what else the need in terms of minerals, they obtain by dissolving the solid rocks to which they attach. Moss are less of an extremophile, but tree moss are one of the few plants that continue photosynthesis through the depths of winter (January 10th).

Returning down-canyon near mile 1.3, ahead, I again here the screeching of a Peregrine falcon. Two falcons are chasing two unidentified hawks away from the sandstone cliffs on the east wall of the canyon near mile 1.0. One falcon easily chases a hawk up canyon and over the ridge. The second hawk begins to climb in lazy, large circles, and the remaining peregrine follows. The peregrine raises higher and then stoops the hawk, all the while screeching loudly. This continues for about 15 minutes. At times I loose sight of the pair as they circle overhead with the Sun behind them. The spring sky is a deep blue, but today, the summer sun makes the atmosphere a white turquoise.

Continuing down-canyon, at picnic site 5 where I collected one sponge, an innovative young couple using long lengths of climbing webbing, have suspended two bright Central American woven hammocks over the stream. They lay side-by-side enjoying the stream-cooled air.

At Guardhouse Gate, there are the cut fireplace-sized remains of a large tree. A quick count of its rings indicates the tree is over one-hundred years old. As the the city cuts down infirm trees in the canyon, they leave the carcasses here as free firewood. The cause of this tree’s demise can be seen in one segment of log – it is riddled to the inner pith with boring beetle tunnels. To supplement my gathering of water borne small life, I also collect from the logs’ surfaces, samples of Green tree moss (probably Orthotrichum sp.) and of orange, black and turquoise lichens.

The lower flood retention pond is full of algae mats. A family of mallards graze on the greenery. The chicks, who a few weeks ago where only four inches long, are now twice that size.

At home, I examine water from the three sponges in under a microscope at 60 power of magnification in order to see some of the smallest plants and animals of the canyon. All of the samples consist mostly of bits of algae, some of which are strung on the ends of mold filament, pulverized bits of plant, and specks of silica. No moving protists are seen. A few rectangular-celled with diatoms with well-defined glass-like walls of the genus Fragellaria are found. Two circular diatoms of the genus Stephanodiscus are seen. Finally, a single, transparent perfectly formed leg of an insect exactly fills the eyepiece and then floats away. This is clean City Creek water.

At home and through the hand-lens, the leaves of the moss, which are present both on trees and on rocks in the stream, reveal their earlier evolution as compared to the leaves of the surrounding trees. They are thin and transparent sheets of green cells, and they lack any vascular features found in true leaves.

Under the hand-lens, where the black lichens interface with the tree’s bark, a separate white hyphae through which digestion occurs. Lichens are composite organisms of algae or green bacteria living symbiotically with fungi. Through the hand-lens, one can see two colors, representing the two organisms in the turquoise and orange lichens. The turquoise portion of the turquoise lichen is also surrounded by white hyphae. The second color is green, and through the lens, these resolve as small bits of algae. That lichens exist on almost all of the trees in the first two miles of road is a good sign. Lichen are sensitive to air pollution and will disappear if Salt Lake’s air quality severely deteriorates over a long period.

The length of the day have changed noticeable from June 20th’s summer solstice. Sunset comes an hour earlier around 9 p.m.

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St. Clair, Newberry and Nebeker (1991 and 1995) provide a comprehensive list of Utah lichens. They and Flowers (1954) describe which species of lichen are common in various northern Utah habitats, including for the scrub oak forest of Gambel’s oaks, the higher subalpine habitat of Quaking aspens, and the montane habitat of conifers. Brodo of the Canadian Nature Museum and Sharnoff and Sharnoff of the Missouri Botanical Gardens published the definite photographic identification guide for lichens: their massive 2001 “Lichens of North America”. They note common lichen species for the Gambel’s oak forest include Lecanora hageni, Phaeoplzyscia orbicu/aris, Physcia adscendens, Physcia dubia, Physcia stellaris, Plzysconia grisea, Xanthoria fallax, and Xanthoria polycarpa. Using these sources, my descriptions and photographs match with the following scientific names:

List of Lichens

• Hooded sunburst lichen (Xanthoria fallax): This is the dusky-orange lichen that covers most of the Gambel’s oak trees in the canyon (Brodo, Sharnoff and Sharnoff, 744).

• Pin-cushion sunburst lichen (Xanthoria polycarpa): This is the bright orange lichen that covers many rocks in the canyon, including the stone bridge at mile 5.2 (Brodo, Sharnoff and Sharnoff, 746).

• Stonewall rim-lichen (Lecanora muralis): This lichen was the even-toned yellow-green (turquoise) circles on rocks along the Pipeline Trail (Brodo, Sharnoff and Sharnoff, 383)

• Sagebrush rim-lichen (Lecanora garovaglii). This is the yellow-green (turquoise) lichen with a darker green center on a rock along the Pipeline Trail (Brodo, Sharnoff and Sharnoff, 380).

• New Mexico rim-lichen ( Lecanora novomexicana): This darker yellow-greenish lichen with yellow fringes was found in the gully near mile 2.2 (Brodo, Sharnoff and Sharnoff, 384).

• Gold cobblestone lichen (Pleopsidium flavum): This is the bright yellow lichen on one rock along the Pipeline Trail. (Brodo, Sharnoff and Sharnoff, 578).

• Powder-tipped rosette lichen (Physcia dubia): This is the delicate leaf-shaped lichen on the limestone vertical fins near mile 5.0 (Brodo, Sharnoff and Sharnoff, 554).

Like today’s Great Salt Lake (May 26th), ancient Lake Bonneville’s water levels and glaciation of the Salt Lake’s canyons at the end of the last ice age gives clues as to the climate of the Salt Lake valley and the canyon. That record is hidden within the valley’s rocks and trees. In 2015 and updating a prior study from 1997, Oviatt at the University of Kansas reconstructed date ranges in which ancient lake rose and fell by radiocarbon dating organic material in tufa deposits along the lake’s former shorelines. He concluded that Lake Bonneville began its rise about 30,000 years ago (id., Table 1). Between 15,000 and 18,000 years ago, Lake Bonneville reached its maximum height at about 5,100 feet, or near the northern end of Pleasant Valley in the canyon near mile 1.7. Following the failure of the Red Rock ice dam in Idaho, the Lake drained to the Provo Shoreline, which is Bonneville Drive and 11th Avenue in the City. Other the next 15,000 years, the lake gradually declined to the current level of the Great Salt Lake (id).

In 2011, Laabs, Marchetti, and Munroe and colleagues used residual Beryllium 10 isotopes in rocks, taken from the glacial moraines in Little Cottonwood Canyon in Salt Lake valley and American Fork Canyon in Utah valley, in order to date when glaciers retreated up from the ancient lake’s shores. An ongoing question existed amongst geologists, based on conflicting earlier studies, concerning whether the Salt Lake glaciers receded before, coincident with or after the end of the last Ice Age and-or before, coincident with or after the end of the peak level of Lake Bonneville. Figure 1 of their study shows the area of glaciation stretching from American Fork to the south and Farmington, Utah in the north, thus, including City Creek Canyon. They concluded that glaciers covering the Salt Lake valley canyons started to retreat 15,700 plus or minus 1,300 years before the present, either during or shortly after the maximum 5,100 foot shoreline height of ancient Lake Bonneville. Their confidence interval overlaps the 15,000 to 18,000 years before the present found by Oviatt for the maximum height of Lake Bonneville. Deglaciation started about 4,000 years after the end of the continental Ice Age at 18,000 years ago. Because the lake reached its maximum and retreat of the local glaciers started after the end of the Ice Age, Laabs, Marchetti, and Munroe et al concluded that the local climate between 18,000 and 15,000 years ago was wetter than thought by prior geologists.

That there were glaciers in City Creek Canyon below Grandview Peak and at the canyon’s final hanging valley (September 8th) seems evident from an examination of any terrain map and hiking the canyon. But to my knowledge, there are no studies dating the glacial deposits in City Creek Canyon. Van Horn and Crittenden’s geologic map shows no surficial glacier features (Van Horn and Crittenden, 1987, U.S.G.S. I-1762). Perhaps there was a lighter ice sheet over the canyon 15,000 years ago, but it was insufficient to crave the bedrock.

The Engelmann spruces and other pine trees that live in association with the spruces, tell the history of Salt Lake valley’s and the canyon’s climate for the last 13,000 years before the present. In Little Cottonwood Canyon, Engelmann spruce share the glacial scoured hillsides with Limber pine (Pinus flexilis). Engelmann spruce is more tolerant of wet earth and colder soil temperatures, and Limber pine is more tolerant of dry earth and warmer soil temperatures. Thus, as climate changes occur over thousands of years, the relative amount of pollen left in soil layers beneath their canopy gives a general indication of weather in the distant past. In 1979, Madsen and Currey at the University of Utah used a bog in Gad Valley near Snowbird Ski Resort to reconstruct Utah’s late Holocene climate (Madsen and Currey 1979). Based on moraine deposits, the maximum extent of glaciation that extruded glaciers into the Salt Lake valley floor occurred about 25,000 years ago. After a period of warming, a second smaller glacial period ensued and Madsen and Currey, using the bog at Gad Valley places that around 12,500 years ago. Then glaciers within Little Cottonwood Canyon retreated and disappeared. A similar bog in Albion Basin at the top of Little Cottonwood is dated at 9,500 years (id, 258). Using the ratio of Engelmann spruce and Limber pine in the Gad Valley bog, Madsen and Currey were able to reconstruct the relative climate of the canyon, and by extension the Salt Lake Valley and City Creek Canyon, for the past 12,500 years. Between 13,000 and 8,000 years before the present, the valley’s climate was cooler and wetter than today. Between 8,000 and 5,000 before the present, advancing Limber pines indicate a warmer and drier climate than today. Then there was a brief period in which temperatures greatly declined, followed by a quick warming and a gradual decline to today’s cooler temperatures with respect to the 13,000 year mean (id, at Fig. 6 and 265). In contrast, precipitation has been on a gradual decline for the last 6,500 years and is currently near the 13,000 year mean (id). These are consistent with Grayson’s climate divisions for the Great Basin Holocene generally: 10,000 to 7,500 years before the present (early), 7,500 to 4,500 years before the present (middle), and 4,500 years before the present until today (late) (Grayson, Chap. 8).

Over the last 4,500 years, a picture of trends in Salt Lake City’s local climate can be developed from tree ring, Gad Valley bog pollen, and other climate research. Since 4,500 years before the present, there was a brief period in which temperatures greatly declined, followed by a quick warming and a gradual decline to today’s cooler temperatures with respect to the 13,000 year mean (Madsen and Currey, Fig. 6 and 265). It is now colder than average than over the last 13,000 years. The Little Ice lasted from about 1300 C.E. to 1850 B.C. There were highly variable swings in temperature during this time, but those changes were not global, but regional (Solomon et al 2007; Houghton et al 2001). In Utah, the Little Ice Age ended in 1850 and was followed by the most severe winter in Utah history, the winter of 1855-1856.

Since 4,500 years before the present, precipitation has been on a gradual decline for the last 6,500 years and is currently near the 13,000 year mean (Madsen and Currey). From 1492 to the present, the tree rings show that persistent, severe droughts were far more prevalent in the distant past than in the 150 years of Euro-American presence in northern Utah (Bekker et al 2014). Variability in Salt Lake City precipitation since the 1960s, including severe drought in the 1960s and peak flooding in the 1980s, is tied to the Pacific Quasi-Decadal Oscillation, an 11 year cycle of drought and heavy precipitation tied to ocean temperatures off the coast of California and Japan. The level of the Great Salt Lake acts as a recorder of climate, and the Lake’s level has been recorded continuously since 1875 (USGS, 2017a, USGS, 2017b). In the summer of 2016, it dropped to a new historical low of 4,190.1 feet (id).

In 2010, Wang and colleagues at the Utah State University associated the Pacific Quasi-Decadal Oscillation (PQDO) with a northern Utah three-year leading precipitation and a six year leading level of the Great Salt Lake (Wang, Fig. 4 at 2166). In the association with the level of the Great Salt Lake, PQDO warm phase peaks are associated with the lowest lake levels and PQDO cool phase troughs are associated with the highest lake levels. In 2013, DeRose, Wang and colleagues used tree rings to reconstruct the level of the Great Salt Lake back to 1429, and they associated the lake’s level to the pacific oscillation back to 1700 (DeRose 2013). In recent years, the PQDO has been good for Utah. While California has suffered severe drought, the PQDO has kept annual precipitation relatively higher in Utah (IWWA Project).

The PQDO has not had a phase change since 1997 and the change to a heavy precipitation pattern is overdue. Despite heavy winter snowfall in the high mountains during the winter of 2016-2107, Utah remains in an extended drought with unseasonably warm summers.

Future uncertainty is added by the effect of global warming. Has global warming disrupted the Pacific Quasi-Decadal Oscillation? What will its future impact be? However, even excluding global warming, Salt Lake City and Utah are on a path towards relatively hotter weather and declining water supplies as compared to the past.

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On July 21st, 1942, the City banned the entire north bench of Salt Lake City to entry due to fire hazard, but access to City Creek Canyon would remain open (Salt Lake Telegram). On July 21st, 1906, the Deseret Evening News published a picture of a 10 foot snow bridge across City Creek Canyon about nine miles up the canyon. On July 21st, prize fighter Tommy Reilly trained by taking a long run up City Creek Canyon (Salt Lake Telegram). On July 21st, 1903, about 100 Ute Tribe members gathered for an annual celebration at the mouth of City Creek Canyon (Salt Lake Herald). (In the present, the Ute Tribe holds an annual meet at Liberty Park.)

July 16, 2017

July 15th

The Homeless and the Canyon

External Link to Image

Bluets on Bulrush in City Creek Canyon at Seep (Lat. 40.8014929, Long. -111.8749328). Author taken July 2017.

3:30 p.m. True summer heat near 100 degrees Fahrenheit returns and the canyon air takes on oven-like qualities of later in the season. While I was born in the cold of the northeast, part of my adolescence was spent under the blazing sun of southern California deserts. My now heated adapted summer body takes the high temperatures easily. The pulse slows; veins and arteries expand; blood flows and cools in hands and legs. Limbs become flexible; muscles relax; and toxins escape through open pores. The mind becomes lethargic and meditative, but with exercise in heat, thinking remains clear.

The heat has emptied the first mile of road, and only a few joggers are present. The road becomes as empty as in the opposite side of the temperature scale, that is in the depth of winter (December 27th). As in winter, I no longer recognize in myself the person who ran through five degree temperatures.

The heat also affects mammals and insects. Counter-intuitively, it makes Rock squirrels active, and I count three in the first mile. Insects begin to succumb. On the road’s surface, Grasshopper (Melanoplus sp.) lays dead, baking on the road, and that carcass is followed by a Giant western crane fly. Next, I find a spent Cabbage white butterfly. This allows me to examine one this usually hyperactive insect with my hand lens. As their name implies, the Cabbage whites are white in color, but close-up their abdomens are jet black. Numerous white hairs cover that segment and make the butterfly appear all-white.

The earth has dried out, and turns the rare cases of stationary surface water in the canyon into oases. The oasis at the seep about 100 yards below picnic site no. 6 (Lat. 40.8014929, Long. -111.8749328) has reached an idyllic peak of diversity. In an ellipsis of sixty by twenty feet, Circumpolar bluets rest on Bulrushes surrounded by Indian ricegrass and fronted by Kentucky bluegrass. These grasses surrounds a water rivulet in which Western Yellowjacket wasps and White Admiral butterflies stop and rest for a drink. Giant cattails are flanked on one side by six foot tall Horsemint (Agastache urticifolia (Benth.) Kuntze), a.k.a. Nettleleaf Giant Hyssop or Nettleleaf Giant Horsemint, covered in Cabbage white butterflies. On the other stands five foot tall blue Chicory. Stands of Starry solomon’s seal are backed by a large grove of Western poison ivy and are intermixed and are intermixed with Common California aster. A cultivar Weeping willow (Salix babylonica) shades the up-canyon end of the glade.

A short-distance downcanyon, three rare butterfly visitors are seen with orange wings, a black circumferential band and white wing spots. These are Mexican queen butterflies (Danaus gilippus strigosus), and they are usually restricted to New Mexico.

Up-canyon, this season’s teasels (Dipsacus sylvestris) have risen to four feet in height below the Red Bridge. For some weeks, the great two foot triangular leaves of the Burdock (Arctium minus Berhn) invasive weeds that line the canyon road have been raising two and three foot vertical stalks, but their purple flower heads have yet to open.

Today, I place three sponges in the lower canyon. The first is in the stream below the pond at picnic site 5. The second is in the seep 100 yards below picnic site 6, described above, and the third in at the watercress stand at the tunnel seep 50 yards below picnic site 6. I will retrieve these in a few days to see what mirco-life has become trapped or grown in the sponge’s cavities.

The intense Sun has boiled huge summer cumulus clouds from the reservoirs that line the eastern side of the Wasatch Front Mountain Range, and the clouds frame the north and eastern ridgelines of the canyon as I reach the Gate. Those reservoirs provide the valley with most of its drinking water. In the parking lot, an elderly gentleman, who each day leaves a homeless concentration zone at 500 West and 200 South in the City to seek the canyon’s cool breezes, sits on a bench eating a sandwich.

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The homeless have long had a relationship with City Creek Canyon. In addition to the homeless person who spends the day at a picnic parking lot, another homeless individual frequents the canyon during the winter, but spends cold nights in a local supermarket. Sometimes in the depths of winter, I have taken the homeless who come to the canyon with the intention of camping overnight back to the city and advise them that they have underestimated the sub-zero temperatures of canyon winter nights. Some are obviously mentally ill. They talk to themselves and their mental illness is either the result of the stress of becoming homeless or an effect of their pre-existing mental illness. For many years, there was a small homeless tent city near the parking lot gate off the Bonneville Shoreline Trail, but in recent years, the County and the City cleared the camp out. Now the watershed patrol vigorously patrols the canyon and takes any homeless citizens back to the concentration zone on the valley floor citing the fear that persons in a homeless camp might set the canyon’s grasslands on fire. While that is a legitimate concern, I suspect the City also quickly acts to remove any homeless from the canyon in part because middle-income citizens simply do not want the homeless there. They fear the homeless as potentially violent and secretly they fear becoming homeless themselves in an uncertain economy.

Salt Lake citizens struggle with the moral ambiguities created by their city’s homeless concentration zone. City residents have long resisted building sufficient facilities to house the homeless on the unsupported theory that building more beds will attract more homeless, and residents, like most other major United States cities, have long avoided building enough affordable housing. The City also struggles with the practice of surrounding communities and hospitals shipping their destitute and ill residents to into the City’s concentration zone. In the 1980s, Salt Lake City took the lead on homelessness by opening Utah’s first homeless shelters. Rather than expending monies addressing their own homeless problem by building their own shelters, for years, neighboring cities have shipped their destitute to the concentration zone citing that Salt Lake City was the only municipality with facilities to house them. Although the concentration zone has become a state and national embarrassment, city residents prefer to keep the homeless out-of-sight and away from other areas of the city, including out of the canyon.

The homeless’ relationship with the canyon goes back farther than this: the homeless built the canyon’s infrastructure. In the nineteenth and early twentieth century, the City dealt with its homelessness problem by shipping the destitute to the canyon. An early Utah statute permitted cities to impress the destitute and mentally ill convicted of the crime of vagrancy into road work gangs (Utah Code Ann. 10-8-85). In the early 1900s, when the City wanted to build a wider, graded road up City Creek Canyon to promote the new automobile tourism, it began systematic sweeps of the city, arresting the homeless for vagrancy as needed to supply laborer for building the canyon’s road (e.g., Salt Lake Herald, Sept. 26, 1910; Salt Lake Telegram, Nov. 11th, 1913). The city police were sophisticated in their sweeps. For example, in 1908, the road gang needed an experienced “dynamite man” to handle explosives used to break up rock ledges along the canyon road’s path. The Police Department did a sweep of vagrants seeking to arrest one with necessary skill (Deseret Evening News, April 24th, 1908). Unemployed miners got wind of the scheme and fled the city. A particularly racist cartoon, by modern standards, in the August 14th, 1904 Salt Lake Tribune shows who was working on road gangs and what residents’ attitudes were towards the poor. The gangs consisted of elderly unemployed men, persons with alcohol addiction, and minorities. On April 28th, 1908, Mark Aaron, a prisoner serving a 90 day sentence for vagrancy, was shot to death in the canyon will attempting to escape the road gang (Deseret Evening News). The officer claimed that he was aiming for Aaron’s legs, but missed and instead the bullet entered Aaron’s head. In 1972, the United States Supreme Court declared vagrancy laws unconstitutional.

This darker era in Salt Lake’s past provides some instruction for the City’s modern homeless problem. What the destitute need to restore their dignity is a roof over their heads and paying employment, even if that means government provided make work. If at night there are any ghosts wandering the canyon, they are probably of homeless men rattling their work gang chains.

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On July 15th, 2015, Mayor Ralph Becker proposes a “Connecting to Nature” plan in which $125 million USD bond would fund park renovations and new land acquisition (Deseret News). On July 15th, 1938, hard oil surfacing of the scenic drive along Bonneville Drive and 11th Avenue was nearly complete (Salt Lake Telegram). On July 17th, 1915, the U.S. Weather Bureau installed an advanced stream flow measuring gauge at the High Line Water Tanks in Pleasant Valley (Salt Lake Herald). On July 15th, 1891, the Red Bird Mine reports opening a four foot wide vein that may contain 1,000 ounces of silver (Salt Lake Times). Fifteen men are working at various prospects in City Creek Canyon (id).

July 13, 2017

July 13th – Revised

The Thoreauian Experience

4:00 p.m. In the near 100 Fahrenheit degree afternoon heat, at a seep along Bonneville Drive leading to the canyon, there is a thick stand of Common goldenrod. Its inflorescences have up to 30 small yellow flowers that each extrude 10 to 15 stamens. It is distinguished from roadside Missouri goldenrod by its serrated leaves (Pratt, Banner, and Bowns 2013). On one flower, a small 2 mm pink unidentified nymph solider beetle is grazing, and as I rotate the angle of the sunlight, its iridescence changes to lavender. Like yesterday, I again go for a short jog to milepost 1.0 and then back down the Pipeline Trail.

With summer’s heat and the proliferation of leaves, disease and opportunistic parasites arrive. In the first one-third mile, there are numerous Narrowleaf Rocky Mountain cottonwood saplings. One the saplings, something is attacking the leaves. At first glance, their leaves look like locust bean pods that have opened, but on closer inspection, some disease is forcing the leaves to fold back and grow four to five small bean-like pockets on each leaf. The newly grown pockets are open at the bottom. I pry several open, but find only one that has a small 1 mm fully-formed gnat inside. It is not clear whether this is some hatched larvae that forced the leaf to form the pockets or whether the gnat has simply crawled inside for protection. On the Pipeline Trail, a single Gambel’s oak leaf that has about ten small red-orange insect larvae attached to its underside. I mark this for a future check to see what develops.

There are only a few butterflies along the road, but at the seep Horsemint (Agastache urticifolia (Benth.) Kuntze), a.k.a. Nettleleaf Giant Hyssop or Nettleleaf Giant Horsemint with lavender inflorescences has matured. The small stand is covered with about 12 Cabbage white butterflies. In the heat, only a few people are on the quiet road and none are on the trail. I am restored.

As I jog through today’s canyon, I try to clear my mind of all thoughts and just experience the canyon’s nature. Although the benefits are commensurate, the amount of time that each day’s excursion takes is great, and this reduces my engagement with friends and a social life. Some see it as self-absorption, although I view it as centering. At a minimum, the practice of daily nature observation provides a restoration of mental attention and executive functions (April 24th and April 25th). From that renewed and centered emotional strength, a better understanding of the day’s political, social and economic events can be had, and only from a position of understanding can actions be formulated that will not make things worse for oneself or ones friends. But is a Thoreauian daily nature experience of nature just another form of modern narcissism?

Based on my experience visiting the canyon each day for almost a year, it is not. Close observation of nature is about sensitivity to and recognition of subtle biological relationships between plants, animals, geology and weather. That study is undertaken in the spirit of husbandry, since humans are the only beings on the planet with sufficient sentience to willfully modify the environment. There are few better metaphors for preparing oneself for a life moral well-being. It is a form of practice for being sensitive to and understanding human relationships. But its practice is only a sufficient condition to becoming a good person, and it is possible to study nature and biology for a lifetime while ignoring the lessons of interconnectedness that it provides.

* * * *

In dueling articles 2015, Pulitzer Prize winner Kathryn Schulz argued in The New Yorker Magazine that Thoreau did not deserve his literary fame: he was simply a self-absorbed narcissist (Schulz 2015). Essayist Jedediah Purdy responded the following day in The Altantic: Thoreau was engaged in the issue of his day – the abolition of slavery – and however awkward he was socially, he wrangling with moral issues remains an instructive today. Thoreau developed the stream in American thought that community injustice committed against some of its members is an injustice against all members of the community. Purdy notes that like Thoreau in the nineteenth century, life today involves moving in the alienating gray area “between feeling the justice and wrongs of our communities as our own and becoming insensate to them” (id). Thoreau’s method of thoughtful engagement, which grew out of his daily, careful observation of nature, is a good approach for daily life in our complex modern world.

That sense of alienation in a gray area of indecisiveness is magnified in modern culture by our cultural insistence that policy decisions should not be based on human values alone, and that experts should quantify and model issues to guide our selections (April 27th). Our ability to quantify and model reality has increased exponentially still the beginning of the digital industrial age in the 1980s, but this has the effect disempowering ordinary citizens (id). Many of the mathematical models that guide modern society, in particular in economics and commerce, are simply rough guides with little statistical validity, and although such modeling does provide a useful check on often-wrong intuition, they are not replacements for the human-valued centered decision-making of Theoreau’s century (id).

Our increased technological ability to collect enormous amounts of information and to model reality continues the dualism between Plato and Aristotle that set the structure of Western civilization two-thousand years ago. Plato was the ultimate deductionist: he felt that the characteristics of an underlying transcendent reality could be deduced and from inferior models of the everyday world. Artistole was the penultimate observationalist and inductive thinker: he felt that things in the everyday world were ends in and of themselves, and thus, observing and enumerating the infinite variations of natural objects was an end in and of itself. Our modern technological society are simply augmented versions of that duality and of Thoreau’s era. I can view mountains of information about the small 3 by 12 square mile canyon collected from sensors and quickly scan millions of research journals and academic books about its weather, wildlife and plants, but in the end, modern scientific research (and my amateur enjoyment of it) is Aristotelian observation followed by Platonic deduction and modeling. Again (see April 27th), the uncertainty generated by knowing the limits of one’s knowledge and careful decision-making supplemented by consideration of expert scientific opinion are important values, but at times, a Thoreauian sense of community alienation and indecisiveness must be set aside and directions chosen from human-centered values.

This tension between our increasing technological prowess and stifling emotional alienation were known to Thoreau. Norte Dame English professor Walls in the preface to her biography released on Thoreau’s 200th birthday (July 12th) argues that since Thoreau lived at the beginning of the Anthropocene era (April 27th), he was struggling with prospects of future environmental destruction, given the American character and that humanity had begun to modify the nature environment on a continental scale (Walls). Menard notes that early American divided their identity into two parts: a “British” identity that was associated with European industrialization and an “American” identity that was forged from their encounter in the new continent (Menard 2012, 600-602). In Thoreau’s famous essay Walking, he concluded that the American character had been shaped by the nature’s wildnesss. Thoreau argued in his famous statement that “Wildness is the preservation of the world”, that nature is a source of continuing replenishment. As America developed across the Mississippi and into the western United States, it needed to preserve undeveloped wilderness in order to maintain its vigor as a society:

“The West of which I speak is but another name for the Wild; and what I have been preparing to say is, that in Wildness is the preservation of the world. . . . The founders of every State which has risen to eminence have drawn their nourishment and vigor from a similar wild source” (Thoreau 1862, 665).

And societies that over-develop and destroy their wild places lose the ability to replenish their vigor and creativity. He attributes that loss to the end of the Roman Empire:

“It was because the children of the Empire were not suckled by the wolf [their destroyed wildlands] that they were conquered and displaced by the children of the Northern forests who were” (Thoreau 1862, 665).

In Walking, Thoreau predicts that if Americans do not preserve wilderness as they expanded into its western territory, e.g. – the Salt Lake valley in which City Creek Canyon is located, then the American character will degrade and decline into a mere “English” society (Menard, 605, 607-608):

“[Y]et we are so early weaned from her breast to society, to that culture which is exclusively an interaction of man on man, – a sort of breeding in and in, which produces at most a merely English nobility, a civilization destined to have a speedy limit” (Thoreau 1862, 670).

One-hundred years later and after considerable development of the West, Wallace Stegner in his Wilderness Letter echoed Thoreau’s reasoning. The American character was uniquely shaped by wilderness and to maintain that character, the residual of wild places left by 1960 must be preserved:

“I want to speak for the wilderness idea as something that has helped form our character and that has certainly shaped our history as a people. . . . Something will have gone out of us as a people if we ever let the remaining wilderness be destroyed; . . . We need wilderness preserved – as much of it as is still left, and as many kinds – because it was the challenge against which our character as a people was formed (Stegner 1960, and “wilderness was working on us”).

Thoreau also argued that daily exposure to natural places was necessary for the maintenance of mental health: “I think that I cannot preserve my health and spirits, unless I spend four hours a day at least – and it is commonly more than that – sauntering through the woods and over the hills and fields, absolutely free from all worldly engagements” (Thoreau 1862, 658). Regular exposure to nature was a condition to well-being: “Will not man grow to greater perfection intellectually as well as physically under these influences?” (id at 664).

Foreshadowing the development since the 1980s of biophilia and attention restoration therapy (April 19th to April 27th), 100 years later after Thoreau, Stegner also concludes that wild places are necessary for our emotional health in light of continuing hyper-development of Western lands:

“One means of sanity is to retain a hold on the natural world, to remain, insofar as we can, good animals. . . . . We simply need that wild country available to us, . . . . For it can be a means of reassuring ourselves of our sanity as creatures, a part of the geography of hope” (Stegner 1960).

The history of the early resource exploitation of City Creek’s Canyon and its subsequent preservation as a natural area parallels these tensions and contradictions (March 20th to April 3rd).

* * * *

On July 13th, 2007, a man was robbed by two women who drove him to City Creek. A second man, working with the women, came out of the bushes and robbed the man using a BB gun (Salt Lake Tribune, Deseret News, July 14, 2007). On July 13th, 1930, forty school girls hiked up City Creek to Rotary Park (Salt Lake Telegram ). On July 13th, 1912, a large fire was reported to have burned between City Creek and Dry Fork Canyons, and E. H. Clark, Wasatch Supervisor organized a canyon fire patrol (Salt Lake Tribune). On July 13, 1908, thousands of residents escaped high summer heat by going to resorts and to City Creek Canyon (Salt Lake Tribune). On July 13th, 1906, efforts to remove the last industrial facility in lower City Creek Canyon, a rock crusher owned by P.J. Moran, continue (Deseret Evening News).

June 23, 2017

June 22nd

Day of the Butterflies

Day of the Butterflies

1:30 p.m. In the heat of the afternoon, the first mile canyon road is lined with butterflies, and in total there are about thirty in the first mile. A large Red Admiral butterfly (Vanessa atalanta), a black butterfly with contrasting red-orange chevrons, slowly moves up canyon. The Red Admiral is hawk of butterflies. Unlike most butterflies, that frenetically flap and change direction, the Red Admiral moves it wings in great, slow soaring motions. Cabbage white butterflies (Pieris rapae) play in the hot sun as western tiger swallowtail (Papilio rutulus) also pass by. Two Common sulphur butterflies (Colias philodice eriphyle) chase each other. Two unidentified butterflies fly by. One is the bright yellow with a trailing black wingbar. The second is a small orange.

Large Common whitetail dragonflies patrol overhead. In the Yellow sweet clover (Melilotus officinalis) weeds that lines both sides of the road, Western Yellowjacket wasps (Vespula penslvanica) feast.

At Pleasant Valley, city watershed crews are mowing the sides of the Pipeline Trail.

* * * *

Per Thoreau’s “Journal” on June 22nd, 1851, he sees blooms of yellow loose strife and bladderwort. On June 22nd, 1852, he sees a rainbow after a thunderstorm. He observes that fireflies are numerous. On June 22nd, 1853, he notes that even night air is warm. During an evening walk, he notes that blueberries are coming in.

* * * *

On June 22nd, 2014, Nathan Peters set a new course record in the 35th annual Wasatch Steeple Chase, an annual running race that goes for 17 miles up City Creek Canyon, that gains 4,000 feet while going over Black Mountain, and end back down at Memory Grove (Deseret News). Two-hundred and forty runners participated. Peters finishes in two hours and eleven minutes (id). On June 22nd, 1996, Mayor Deedee Corradini temporarily ordered suspension of construction of the Bonneville Shoreline Trail due to complaints from Avenues’ residents (Salt Lake Tribune). Planning Commission Chairman Ralph Becker noted that that a controversial trail alignment near Ensign Peak was a condition of the developer receiving approval for a luxury subdivsion (id). On June 22nd, 1906, an Intermountain Republican editorial accused the Salt Lake Tribune of spreading lurid lies about Mormon culture in eastern newspapers, including that “Utah is steeped In lawlessness; that depravity runs riot; that the waters of City Creek canyon going down our gutters [are] tinted with the ruddy flow from blood atonement; that all Mormons are polygamist; and that a presentable woman is in peril of than her life . . .”

June 22, 2017

June 15th

First Day of the Estival Season

4:30 p.m. It is the first day of the Estival ecological season, the time of greatest heat (Feb. 16th). Astronomical summer begins on June 20th. The late spring heat wave continues and temperatures in the low nineties. I drive to the canyon for short jog, and as I exit the car, my senses are assaulted. The top of a large Douglas fir is heavy with new cones. A Rock squirrel scampers across the parking lot. Curly dock is turning its summer brown. Several Western tiger swallowtails chase each other. Cabbage white butterflies wind between tree branches. A Song sparrow sings loudly. For the first time this year, the air smells of summer and of greenery under hot a sun. All of this occurs within the first quarter of a minute.

The stream’s flow is dropping, but its depth is medium. At the base of the fir, its pine cones also show the Fibonacci whirl pattern seen in bull thistle blossoms (June 10th). The blossoms of Solomon seal plants along the first mile are fading, and some of the plants are beginning to brown.

With the addition of the last summer quality, heat, the canyon is transformed by insects. Previously, light has been increasing throughout spring, and melting snow and violent storms have added water. Heat is last elemental that completes the canyon’s return to prolific life after last winter’s sleep. The first mile has become a boulevard of butterflies. There is a mini-explosion of Cabbage white butterflies in the first quarter mile, and about twenty line both sides of the road. They are joined by Painted lady and Spring azure butterflies. An unidentified yellow butterfly with a black band on its trailing wing line flutter. In the Yellow sweet clover and Red clover weed (Trifolium pratense), which is a purple-blue invasive in Utah, are laced with Yellow-jacket wasps and domestic Honey bees. Above my butterfly escorts, a new large, brown dragonfly with black-spotted wings has matured. These are massive for a flying insect – about three inches across. These are female Common whitetail dragonflies (Libellula lydia). A large four inch mosquito, the common Floodwater mosquito (Aedes vexans), has perished on the road, and since it is unmoving, I can examine its otherworldly structure. This nationally-distributed Floodwater mosquito is a secondary vector for dog heartworm, and more recently in states other than Utah, it has been implicated as transmitting West Nile virus. In Utah, the common House mosquito (Culex pipiens) is the primary vector of West Nile. I am walking through a garland of butterflies.

* * * *

Per Thoreau’s “Journal” on June 15th, 1840, he admires the reflections of trees in water. On June 15th, 1851, he sees the first wild rose of the season, blue-eyed grass, yarrow, blooming lambkill, and Solomon’s seal. He lists a series of spring flowering plants. On June 15th, 1852, he hears crickets and sees dandelions, fleabane, sorrel and purple orchids blooming. He hears a seringo and a hawk. At night, he sees fire flies and the reflection of a bright star in water. On June 15th, 1853, he notes that clover is at its peak and sees many wild roses in bloom. On June 15th, 1854, he notes that birds are singing less. On June 15th, 1858, he notes wool grass growing in a meadow.

* * * *

On June 15th, 1909, a teamster, William Luther, had his legs crushed in an truck accident while hauling gravel along City Creek Canyon Road. On June 15th, 1902, the Salt Lake Tribune argues in favor of residents using filters to better purify domestic water, in part coming from City Creek Canyon.

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).

May 22, 2017

May 22nd (Revised)

Continental Scale Bird Population Trends – Part I

(Science Section Revised May 28th.)

1:30 p.m. It will be a good day. As I ready to leave for the canyon and before even starting the car, a brilliant red House finch lands on a nearby telephone wire and sings happily for five minutes. Bright sunlight floods the canyon, and spring life explodes. There is too much to see, and I am overwhelmed. The roadside heats up with smells of fresh growth, and it mixes with the crisp cool air that rises from the transparent, chilled water of the swift stream. In the first mile, fifty birds are active, all singing in cacophony. The red ozier dogwood bushes are covered with small one-half inch bees with yellow and black abdomens and similarly miniature wasps with black and white striped abdomens. The first Western Yellowjacket wasp of the season lands. Nine Yellow swallowtail butterflies line the first mile with Mourning cloak, White cabbage, Painted Lady, and Spring Azure butterflies. Two Blue-eyed darner dragonflies fly above the road, and one unceremoniously defecates as it passes.

Immediately past Guardhouse Gate, three Warbling vireos exchange calls from the surrounding trees. Along the road to mile 0.3, I can distinguish about fifteen bird songs and calls, but by sound, I can identify the American robin, a Mountain chickadee, the Black-headed grosbeak, and the Song sparrow. A small Blue-gray gnatcatcher (Polioptilidae Polioptila caerulea) jumps parallel to the road along oak branches. Black-chinned hummingbird wings beat loudly.

At the bend in the road above picnic site 3, there is another riot of bird songs in a small cluster. Songs of the House finch, Mountain chickadee and others blend together. Then a blazing Yellow warbler comes of the screen of trees and lands in a nearby branch. The warbler leaves and finally, a Western scrub jay lands on a another branch. I play a recording of one of its kind squawking, the blue shouldered bird replies. This way we have an odd conversation. There is more, but this is enough.

This is the green explosion that the vernal season (February 16th) has been building to since the first of May.

* * * *

Parrish, Norvell and Howe’s Utah bird study covers one state – Utah (Parrish et al. 2007; Novell, Howe and Parrish 2005), but birds are international travellers. Olsen’s Pacific Flyway data is international but regional (Olsen 2017). Because of their dispersal, bird trends also need analysis on the continental scale. In 1966 in response to DDT’s impact on birds, the U.S.G.S. and the Canadian Wildlife Service began the first North American continental Breeding Bird Survey (BBS). However, design of the BBS did not cover weighted areas of differing habitat types (Bart 2005; Parrish et al. 2007 at 11). All survey sites were along roads, and this introduced a bias that would not allow for the study of how changes in habitat affects bird populations (id). Acknowledgement of the need to have coordinated continental scale non-game, longitudinal bird population data led to the establishment of the Partner-in-Fight Working Group (Bart 2005) to supplement the Breeding Bird Survey, and Parrish, Norvell and Howe’s work on Utah riparian habitats was part of the Partners’ system. Governmental agencies, including Utah, consolidate results into the national Breeding Bird Survey database (Sauer 2017; Pardieck 2016). Both the BBS and the Partners-in-Flight programs focus on professionally trained biologists working for or associated with many governmental agencies collecting high quality data by conducting transect surveys over time at the same sites.

Through 2015, the Breeding Bird Survey shows a declining population at 1.4 percent per year in its Western region (Sauer 2017). Plumbeous vireos decline at 2.3 percent per year.

Since the 1990s, concerns grew over what impact climate warming might have on bird populations and a need was perceived to develop management tools to early identify adversely effected bird species, and a management tool, the Partners-in-Flight the Conservation Concern Index was develop to provide guidance under the conditions of uncertainty in estimating local and global bird populations and their trends. The Partners-in-Flight methodology rates stresses on bird populations for 1,154 bird North American bird species (Panjabi et al 2012) based on five non-dimensional, ascending scales ranging from 1 (least concern) to 5 (most concern). The five indices are global population size, breeding geographical distribution, non-breeding geographical distribution, threats to surviving the summer breeding season, threats to surviving the non-breeding season, and population trends, and the combined indices yield a maximum total score of at most 25 denoted as the “Conservation Concern Index”.

Of the five indices, the global breeding population size is the most sensitive. It varies by a geometric growth rate of 10 denoted by a logarithmic index:

5 – World breeding population is less than 50,000 or 5 x 10^4.

4 – World breeding population greater or equal to 50,000 (5 x 10^4) and is less than 500,000 (5 x 10^5).

3 – World breeding population greater or equal to 500,000 (5 x 10^5) and is less than 5,000,000 (5 x 10^6).

2 – World breeding population greater or equal to 5,000,000 (5 x 10^6) and is less than 50,000,000 (5 x 10^7).

1 – World breeding population greater or equal to 500,000,000 (5 x 10^8) (Panjabi et al 2012).

The global breeding distribution index is the second most sensitive. It varies by a geometric growth rate of 3 denoted by a logarithmic index. An index of “5”, or highest concern, corresponds to 80,000 square kilometers or a U.S. state size of about 300 kilometers square. A breeding distribution index of “1”, or least concern, corresponds to 4,000,000 square kilometers, or a continent-sized 2,000 kilometer square(Panjabi et al 2012).

The Populations growth index is the least sensitive. An annual growth decline rate between 0 and 15 percent is rated “3”. Only crashing populations with a growth rate of greater than 50 percent are have an index of “5”.

Logarithmic risk indices are intended to overcome human compression bias, i.e. – our tendency to misinterpret risk over a large range of outcomes (Adams and Smith). Humans overestimate the risk of rare events, like botulism, and under estimate the risk of common events, like heart attack (id) and many natural processes, for example from our hearing and sight, increase sensitivity by a geometric scale. Thus, a logarithm index is a useful abstraction, but it is still often misperceived. If a risk level is expressed in terms of raw data, e.g. a world population breeding size of 50,000 to 500,000,000, this lends to unwarranted accusations of overstating for conservation. Conversely, when confronted with a logarithmic index, the natural human tendency is to erroneously interpret risk as an arithmetic sum. The earthquake Richter scale is a useful, common analogy. An earthquake of 5.0 on the Richter scale will shake the picture frames on your walls, but an earthquake of 7.5, will turn your home into a pile of sticks. The effects are perceived as additive, but in reality the effects are exponential.

To supplement the governmental North American Breeding Bird Survey by applying the Panjabi et al criteria on a global scale, private groups and industry from the North American Bird Conservation Initiative (NABCI). NABCI analyses are reported in annual glossy “North American State of the Bird” reports, – e.g. North American Bird Conservation Initiative (2009) and North American Bird Conservation Initiative (2016a). Another useful form of the their results is the annual NABCI Assessment Database, a spreadsheet that allows the user to sort and select birds by risk and habitat North American Bird Conservation Initiative (2016b). The mean of the index is 11.5, and a Conservation Concern Index higher than 13.5 suggests a high level of concern for which further study and action should be taken. A Conservation Concern Index (CCI) of 8.5 to 13.5 denotes moderate concern. This continental scale study provides insights into future threats that might change the currently stable bird diversity and populations totals seen in the canyon. But again, the CCI is a management tool and it does not report additive risk. Because its two key component scales, global breeding size and global breeding area, are logarithmic, the CCI scale conveys an expert opinion of a geometrically or exponentially increasing risk.

Two spring species that are regularly seen in the canyon (May 6th, May 20th) have CCI’s of 13 at the borderline of high concern: Virginia’s warbler and Plumbeous vireo. Others in the moderate concern category and their concern indices are: Broad-tailed Hummingbird (12), Steller’s Jay (11), Dusky Flycatcher (10), American Dipper (10), Black-chinned Hummingbird (10), Mountain Chickadee (10), Townsend’s Solitaire (10), Lazuli Bunting (9), Northwestern Crow (9), Orange-crowned Warbler (9), Western Scrub-Jay (9), and the Western Tanager (9). One commonality between these 13 species of 149 known to visit the canyon are that their non-breeding season ranges are in the southern Mexican highlands or the Pacific Coast lowlands. In short, land development in distant places might reduce their annual appearance in the canyon. But these results should be read in context. The NABCI indices for species found in the canyon generally indicate there is low concern of immediate threats to most species. The diversity of bird species in the canyon is stable. The NABCI “State of Birds” reports are not a trend-based forecast, although their short annual narrative report incorporates conclusions from Christmas Bird Count trend studies by the Audubon Society and governmental Breeding Bird Surveys.

* * * *

On May 22nd, 1914, the newly completed scenic automobile drive up City Creek and along 11th Avenue to be called Wasatch Boulevard will be opened to the public (Salt Lake Tribune). Other park improvements include the new Thirteenth Street Reservoir Park and adding lawn areas to Liberty Park (id).

May 20, 2017

May 20th

Spring Bird List

3:30 p.m. In the morning I am woken by the cawing of an American crow (Corvus brachyrhynchos) standing outside my window, but then I drift back off to sleep. Around noon, neighbors are buzzing over their photographs of a common Red fox (Vuplus vulpes) hunting mice in the city cemetery about one-third of a mile from my home and on the south-City side of the east-south canyon ridgeline.

In the afternoon, the cold snap of the last few days has ended and the canyon is again warming into the sixties under blue, ideal spring skies. Driving into the canyon along Bonneville Drive, the grasses have reached up to three feet high, but in the canyon they remain between one foot to eighteen inches in height. Along Bonneville Drive, young Curly dock plants rise, but there are none in the fields at mile 1.5. Arrowleaf balsamroot has noticeably disappeared from the surrounding hillsides through mile 1.5, and its yellow color has been replaced by the duller yellow of fields of Dyer’s woad. Along the first mile, where a few days ago there was a single Sticky Wild Geranium, there are now ten, and four blue penstemons are blooming. The other major blossom are the white inflorescences of chokecherry bushes or trees. Blue is the color of canyon near the stream, but at the Pleasant Valley lower field, I scan the surrounding hillsides for a hint of Arrowleaf balsamroot. There is none, only the green of the balsamroot’s wide bases surrounded by wide swaths of Dyer’s woad. A pattern repeats in the many sun-exposed small gullies that lead to the western salient’s ridgeline and below the eastern salient’s cliffs: Groves of green Gambel’s oak or Red Maple fill the damp soil or seeps along side canyon gullies, but where the side canyons begin to flare out, the dryer soils, formerly covered with balsamroot, are now covered in Dyer’s woad. At lower elevations along the western slope above the Pipeline Trail and above Bonneville Drive, some balsamroots remain in bloom, but their numbers are rapidly dwindling from their shriveling flowers.

Butterflies are recovering in the rising heat. Yesterday’s Western tiger swallowtail and Desert Elfin butterflies are joined by a few Spring Azure and White cabbage butterflies. About eight new, small and black unidentified butterflies appear. They move too fast to see any detail. Two examples of a new unidentified small black spider are on the road, and a small black ant is carrying a whole insect pupae, about eight times it size, back to its underground ant lair. Common houseflies are active on the road, and a larger Blue-eyed darner dragonfly patrols up and down the road. Along the Pipeline Trail, I flush out two Mormon crickets. Instead of red underwings (May 8th), they now flash muted orange underwings.

Where the chokecherry bushes are warmed by the sunlight, they are the buffet for the insects. The best of these is along the Pipeline Trail near mile 0.9, and the chokecherry bush is covered in about seventy bees, flies and a American Lady butterfly. The bush sits near a seep in a bend in the trail. It is in a large-tree shaded area, but a single shaft of light penetrates and warms the bush and its nearby air to fifteen degrees more than its surroundings. Another shaded chokecherry bush about fifteen feet away is ignored by these flighted insects. On the chokecherry inflorescences there are also two types of flies, one large and one small, and three types of bees, including a red-rumped worker bumble bee, wild common honey bee (Apis var.) and one of two Utah varieties of the Carpenter bee (Xylocopa californica) (Hodgson and Trina 2008). Near this seep, a tiny unidentified slug, about 1 centimeters by 3 millimeters in diameter crawls up the trail, and I help to the mud next to the seep. Three other chokecherry bushes fifty yards up from Guardhouse Gate and a full chokecherry tree at picnic site 4 are similarly covered, but to a lesser degree. These are also sunbathed.

A flock of four distant raptors circle and glide up canyon. Birds along the first 1.5 miles of road can be divided roughly into seven neighborhoods or groups: at Guardhouse Gate, at road mile 0.4, at road mile 1.0, the lower half of Pleasant Valley, mile 1.1 to 0.9 of the Pipeline Trail, the Trail between mile 0.9 and 0.5, and the Trail between mile 0.5 back to the Gate. There are more calls than yesterday, with between 5 to 10 birds in each neighborhood. By sound alone, I can pick up a few of the easiest out of a chorus of ten different songs: the Lazuli Bunting at the Gate; a Song sparrow and an American Robin near mile 0.5; a near road mile 1.0,; and a Black-chinned hummingbird flying near Trail mile 1.0. I have gathered recordings of about 40 spring birds on my smart telephone, and have begun to replay them constantly in the hopes of building a beginner’s skill for distinguishing their songs. The avian soundscape is being to make more sense to my untrained ear.

As I reach Guardhouse Gate, there is a young woman standing 50 feet from the road, half obscured by blinds made leafed branches of Gambel’s oak, and she is singing gospel and folk songs in a loud but beautiful voice. She has long-black hair, is wearing a short, summer dress of yellow printed ethnic cotton, and is illuminated by that special warm light before dusk. Several strolling couples and myself discreetly walk up to the side of the road for an impromptu concert. For a moment, my mind is momentarily transported back to my adolescence and a similar scene from 1971. After a few minutes, everyone wanders away, leaving her to practice her singing without disturbance, but grateful for a unique moment.

* * * *

The slate of spring canyon birds for this year has sufficiently filled out that a list is timely. The 54 species represented shows the diversity of bird life that is finding living niches in the canyon and making connections between its plants and insects.

List of Spring Birds in City Creek Canyon March through May, 2017 by Order and-or Family (N=54)

Orders Accipitriformes and Falconiformes – Hawks, Eagles and Falcons – Birds that Hunt Other Birds

• Bald Eagle (immature) (Haliaeetus leucocephalus).*

• Cooper’s Hawk (Accipiter cooperii).

• Golden Eagle (Aquila chrysaetos).

• Northern Goshawk (Accipiter gentilis).

• Peregrine Falcon (Falco peregrinus).

• Red-tailed Hawk (Buteo jamaicensis).

• Sharp-Shinned Hawk (Accipiter striatus).

Order Anatidae – Ducks

• Mallard (Anas platyrhynchos).

Order Apodiformes – Swifts and Hummingbirds

• Black-chinned Hummingbird (Archilocus alexandri).

Order Galliformes – Pheasants and Guineafowl

• California Quail (Callipepla californica).

• Chukar (Alectoris chukar).

• Wild Turkey (Meleagris gallopavo).

Orders Piciformes and Coraciiformes – Woodpeckers and Kingfishers

• Belted Kingfisher (Ceryle alcyon).

• Downy Woodpecker (Picoides pubescens).

• Northern Flicker (Colaptes auratus).

Order Strigiformes – Owls

• Western Screech-Owl (Otus kennicottii).*

Order Passeriformes – Larger Perching Birds

Family Corvidae – Crows, Jays and Magpies

• American Crow (Corvus brachyrhynchos).

• Black-billed Magpie (Pica pica)

• Common Raven (Corvus corax).

• Steller’s Jay (Cyanocitta stelleri).*

• Western Scrub-Jay (Aphelocoma californica).

Order Passeriformes – Mid-sized and Smaller Perching Birds

Family Cardinalidae – Cardinals and Grosbeaks

• Black-headed Grosbeak (Pheucticus melanocephalus).

• Lazuli Bunting (Passerina amoena).

• Western Tanager (Piranga ludoviciana).

Family Columbidae – Pigeons and Doves

• Eurasian-collared Dove (Streptopelia decaocto) (invasive).

• Mourning Dove (Zenaida macroura).

Family Emberizidae – Sparrows and Buntings

• Chipping Sparrow (Spizella passerina).

• Dark-eyed Junco, Slate type (Junco hyemalis).*

• Green-tailed Towhee (Pipilo chlorurus).

• House Sparrow aka European Sparrow (Passer domesticus) (invasive).

• Rufous-sided Towhee (Pipilo erythrophthalmus).

• Song Sparrow (Melospiza melodia).

• Spotted Towhee (Pipilo maculatus).

Family Fringillidae – Finches

• House Finch (Carpodacus mexicanus).

• Lesser Goldfinch (Carduelis psaltria).

Family Hirundinidae – Swallows

• Bank Swallow (Riparia riparia).

• Cliff Swallow (Petrochelidon pyrrhonota).

• Northern Rough-winged Swallow (Stelgidopteryx serripennis).

• Violet-green Swallow (Tachycineta thalassina).

Family Paridae – Chickadees

• Black-capped Chickadee (Poecile atricapillus).

• Mountain Chickadee (Poecile gambeli).

Family Parulidae – Wood-Warblers

• Orange-crowned Warbler (Oreothylpis celata).

• Virginia’s Warbler (Oreothylpis virginiae).

• Yellow Warbler (Dendroica petechia).

Family Turdidae – Thrushes

• American Robin (Turdus migratorius).

• Townsend’s Solitaire (Myadestes townsendi).

Family Tyrannidae – Tyrant Flycatchers

• Dusky Flycatcher (Empidonax oberholseri).

• Olive-sided Flycatcher (Contopus cooperi).

Family Vireonidae – Vireos

• Plumbeous Vireo (Vireo plumbeus).

• Warbling Vireo (Vireo gilvus).

Family – Other with Family Name

• Blue-gray Gnatcatcher (Polioptilidae Polioptila caerulea).

• European Starling (Sturnidae Sturnus vulgaris) (invasive).

• Red-breasted Nuthatch (Sittidae Sitta canadensis).

• Ruby-crowned Kinglet (Regulidae Regulus calendula).

Sources: Cornell Lab. 2017 Ebird Observation Lists by Bryant Olsen with Joshua Hunt; Author’s Observations. * – Author only sighting claimed.

* * * *

The Wasatch Front Mountain Range has not seen a decline in the number of avian species since the Euroamerican arrival, but no opinion is expressed on any decline in the population of these birds. As noted before (March 4th), ornithologist Robert Ridgeway conducted a survey of birds in Parley’s Park at the summit of Parley’s canyon about ten miles from City Creek Canyon between June 23rd and August 16th, 1869 (Rawley, 69-79). He found 116 bird species. Comparing Ridgeway’s list with Cornell Ornithology Laboratory’s Ebird List for City Creek Canyon for 1900 through 2017 shows 149 species (Cornell Ornithology Lab. 2016, Cornell Ornithology Lab. 2017). For the years 2000 to 2017, 147 species are listed, and for 2012 to 2017, Cornell totals 143 species (id). There are some minor non-duplicates between the historical and modern lists. The Yellow-bellied sapsucker is not currently found in City Creek, and the range of other birds has changed. Birds such as sandpipers and Sandhill Cranes do not presently frequent City Creek but can still be found at the Great Salt Lake’s beaches and marshes. But essentially, the avian diversity of Ridgeway’s 1869 mountain birds is still intact at City Creek Canyon after 148 years.

That the diversity of Utah’s many migrant birds is stable is also shown by Parrish, Norvell, and Howe of the Utah Division of Wildlife Resources in a multi-year study from 1992 to 2005 (Parrish et al. 2007; Norvell, Howe and Parrish 2005). Examining 202 statewide bird species over 12 years at 37 Utah sites, Parrish and colleagues found no significant trend in mean annual species richness (id, p. 27, Fig. 4).

* * * *

On May 20th, 2014, Salt Lake Fire Captain Scott Winkler reports that the City has spent $650,000 on six new firetrucks specialized from fighting fires in grass brush areas around luxury homes near Ensign Peak and in City Creek Canyon (Deseret News). On May 20th, 1903, the City Council and Mayor considered issue bonds to construct reservoirs including a 5,000,000 gallon reservoir at Pleasant Valley (Salt Lake Telegram). On May 20th, 1901, an estimated three-hundred people went up City Creek Canyon, one-thousand to Liberty Park, and three-hundred for recreation (Salt Lake Tribune). On May 20, 1896, the City council considered moving the responsibility for maintaining City Creek watershed protection to the health department and the duties of the City Creek Canyon patrolman were described (Salt Lake Tribune). There were five full-time patrolmen. Three men are employed at the lower Brick Tanks keeping the screens clear of debris. Two men are employed for 12 hours per day to service the upper high-line tank screens and to patrol the upper canyon to prevent sheep grazing. Two other men service the Twentieth ward tank and the Capitol Hill Reservoir (id). City Creek has been rip-rapped for two miles above the lower Brick Tanks. On May 20th, 1896, high spring run-off has turned City Creek into muddy water and the water is clearing (Salt Lake Herald).

May 13, 2017

May 10th


Midnight. In the valley, temperatures are in the low sixties, and this means overnight temperature in the canyon is in the fifties. Everything is in place – water, soil, nutrients, leaf, flower, and life – and the great vernal explosion of growth has begun. My pen and typewriter feel inadequate to the task. With the vernal explosion, everything in the canyon is changing so rapidly, and it is possible only to record a fraction of and a general impression of what is occurring.

4:00 p.m. As I exit the car at the parking lot, a Peregrine falcon zips overhead traveling west to due east. As I start up the road, a Red-tailed hawk is soaring overhead, hovering effortlessly and then moving to the west at a few miles an hour. A down canyon wind just balances it needs for lift and forward propulsion. There about thirty bird calling and singing in the first mile. I can hear the songs of the Dark-eyed Junco, a Western tanager, and the Lazuli Bunting. The bunting also makes separate chirping call. All the song birds are unseen and hidden in the forest.

Woody shrubs are the most prominent flowering plants, and along the first road mile simultaneously, Red-ozier dogwood, serviceberry (Amelanchier sp.), and chokecherry (Prunus virginiana) bushes are blossoming. When heated by sunlight, chokecherry blossoms give off an enticing vanilla odor, but it is not produced when the bush is in shade. On a dogwood complex funnel-like inflorescence, a Western honey bee (Apis mellifera) feeds. At Guardhouse Gate and at the Red Bridge, below Horsechestnut inflorescences, waxy seed pods form. River birch leaves have grown to two or three inches and with hot sun, now are covered in a shiny, wax layer. This may be an adaptation to retain water. At picnic site 1, a pretty flowering invasive, the Star-of-Bethlehem (Ornithogalum umbellatum L.), has about ten blossoms close to the ground. This bulb perennial has small white star-shaped petals that surround a green rim and a set of second interior white petals.

There are about twenty recently common butterflies in the first mile: White cabbage; Painted lady; Zerene fritillary (doubtful); Desert Elfin; and, Western tiger swallowtails; and, Spring Azure. Three examples of new unidentified moth appear. Moths are distinguished from butterflies as they rest. Butterflies fold their wings vertically after landing; moths spread their wings horizontally flat. This small one to two inch moth is light brown, but has a rectangular medium dark brown bar above the trailing edge of its wings.

Ants are active on the road: a tiny black species and larger Carpenter ants (Camponotus sp.). One of the tiny black ants crosses the road carrying a transparent fly wing in its mandibles.

Over the last week and again today, I see a small furry brown bee hovering over the road. To my eyes, it is suspiciously off somehow; the “bee” only has two and not four wings. This is the Black-tailed bee fly (Bombylius major). This fly also has a distinctive long-straight proboscis for sipping nectar, and it lays eggs on bee larvae. I am feeling ill and diarrhetic, and today, for the first time in over two decades, I am compelled to run into the bushes to defecate. Bags that I use to pick up dog droppings from the road are used to remove the mess from the watershed. While this in the category of too much personal information, there is a lesson to be learned. Within less than a minute, the waste mound is covered in over seventy-five flies of three different types, but I make no attempt to identify them. Normally, bees are unseen along the canyon roads and trails, except near waste containers or deer dung piles, but today’s accident reveals that there are hundreds of flies hiding in the bushes and leaf litter. They are both pollinators and nature’s important garbage collectors. Although they favor mule deer and my human droppings, they are less quick to visit canine waste piles left along the road. The flies in turn become food for birds. About ten miles to the west at the Great Salt Lake flats, brine flies fuel the Utah portion of the Pacific Flyway of migratory birds. In a month at the Lake, beaches and lake bed flats will covered in brine flies such that the surface appears to move. Birds wade through the living mass, gorging themselves. In the canyon, the flies restrict themselves to the cool forest understory, and hopefully they feed the Lazuli buntings, warblers and other song birds.

While the flies in the marshes and beaches of the Great Salt Lake support millions of birds, the density of flies in the canyon may be too low, and canyon flies can only supplement canyon the birds’ diets. Assuming based on my accidental experience that there is about one fly per square foot to a depth of fifty feet on either side of the stream and that each fly weighs 12 micrograms, then the first mile holds about 6.3 kilograms of flies (0.12 x 2 x 5,280 x 50). If there are about 50 small birds living in the first canyon mile and each weigh about 100 grams (about 3.5 ounces), then the bird’s mass is about 5 kilograms. Flies alone are insufficient to support the small birds’ higher trophic level.

* * * *

A 2010 Tibetan study of the ecological role of flies and beetles quantifies their effectiveness in removing animal waste from prairies. Wu and Sun placed 248 gram patties of yak dung under screens that allowed either flies alone, beetles alone, or flies with beetles in Tibetan alpine meadows for thirty-two days. Over one month, the beetles removed sixty-seven percent (168 grams) of dung and the flies removed fifty-one percent (127 grams) of the waste. Using Black solider flies, similar results have been obtained by farm management scientists who have used the flies to reduce the volume of livestock waste by 42 percent (Diener, Zurbrugg and Tockner 2009). In the canyon, I have anecdotally noticed similar rates of removal of Mule deer scat by flies and beetles.

What ornithologists know about what birds eat comes in part from a remarkable series of studies by F. E. I. Beal of the United States Department of Agriculture from the first half of the twentieth century in which birds were actively killed and then the contents of their stomachs were examined (Beal 1900, 1911, 1915, 1918). For example, ten robins were taken alfalfa fields in Utah, presumably in the valley and in the region of the canyon, and twelve percent of their stomach contents were beetles (Beal 1915, 6). Thoreau also recorded bird stomach contents. Although he would not kill himself, when his neighbors shot local birds, he sometimes examined the contents of their stomachs (e.g. Thoreau, Journal, January 11, 1861). In a more humane era, non-destructive direct observation of feeding habits and bird feces are studied (e.g. White and Stiles 1990).

* * * *

On May 10th, 1910, the City Commission argued over Chief Engineer’s expenditures to study how to increase the city water supply, and the Commission order all work to stop on waterworks improvements in City Creek Canyon (Salt Lake Herald).

May 10, 2017

May 7th

Iridescent butterflies

4:00 p.m. Red-ozier dogwoods are blooming. Gambel’s oak trees at picnic site 1 have leafed-out to between two and four inches, but some of these oaks higher at mile 1.0 have no leaves. At Pleasant Valley, grasses are twelve inches high and move in waves in response to breezes. The high canyon walls are all covered in these green waves. Along the Pipeline Trail, red maples have leafed out to four inches. Mullein stalks are beginning to rise. Along the Pipeline Trail, 20 or 30 birds can be heard, but only yesterday’s male Black-chinned hummingbird puts in an appearance at its usual post on the powerline. No soaring raptors are seen today.

The thirty or forty butterflies in the first mile are dominated by Orange Sarah tops and Desert Elfin (Incisalia fotis fotis) butterflies. Below picnic site 1, an unidentified red-brown caterpillar hangs from a Box Elder tree by a twenty-foot long silk thread, and as the wind blows it sways back and forth in large five foot arcs. It does not know whether to go further down or up. At picnic site 3, an unidentified beetle lites onto a table, and in a ray of sunlight, a patch on its back radiates a bright lime green. Near mile 0.5, a small black ant drags a dead lime green caterpillar back to its nest. Along the Pipeline Trail, a Common sulphur butterfly moves between and drinks from Arrowleaf balsamroot blossoms, and more than ten Stink bugs are active on the trail. I miss nearly stepping on one that is laid out, legs splayed wide, on the trail. My foot alarms it and it springs up and lands in a defensive posture. Back at the Guardhouse Gate, I notice a Cabbage white butterfly fly into a bush, inexplicably struggle, and then frenetically fly off. Close examination shows the circular web of an orb weaver spider (Araneus sp.). This unidentified spider has wonderful orange, white and black spotting on its abdomen, but I am unable to photograph. My autofocus camera only sees the background and refuses to make a sharp image of the tiny spider in the foreground.

Just before Guardhouse Gate, two mallards, one-male, one-female, are standing right next to the road unafraid of humans. The male is half-asleep and appears contemptuous of people. The female is feeding on roaches under the leave litter. She digs through the leaf litter and rapidly opens and closes her beak. This separates the chaff of the dead leaves from the wheat of the small bugs. In the Guardhouse Gate parking lot, an immature Rock squirrel is browsing in the middle of the road. I pull out the car and chase him back into the brush with flashing lights and a honking horn. I am teaching the squirrel to be afraid of cars. For this squirrel, there will be no repeat of finding it dead on the road, as seen last summer.

* * * *

Butterflies also have ultra-violet vision used in differentiating flowers, but some may use iridescence and the uv spectrum to communicate between themselves (Doucet and Meadows, 2009; Buront and Majerus, 1995). Butterfly wings are covered in miniature scales that like the feathers of birds make colors have diffraction. In 1968, an experiment of Obara and Hidaka at the Tokyo Institute of Agriculture and Technology demonstrated that male Cabbage White butterflies locate their mates primarily by visual clues (Obara and Hidaka, 1968). They sealed females and male dummy butterflies in Petri dishes in order to prevent the males from finding their mates by smell. Since male and female Cabbage whites look nearly identical in the visual spectrum, how could the males tell them apart? Ultra-violet photography revealed that the wings of female Cabbage whites are white or patterned and the males are totally dark. On 2008, Obara and colleagues repeated this experiment, but noted that females have subtle changes in their UV color during the summer, and males preferentially mate only with the summer-colored females (Obara et al 2008). In 2000, Knuttel and Fiedler at the Universitat Bayreuth suggested that this was not a universal principle. They found that many species of butterflies appear different in the visual and uv light, but the variations within species where larger than between species and were not so great as to be a means discriminating between or within species (Knuttel and Fiedler, 2000; Buront and Majerus, 1995, same). Iridescent differences in the visual spectrum is dominant in butterflies when distinguishing between individuals (id). Butterflies also have iridescent colors in order to confuse predators or to warn them that the insect is poisonous (Doucet and Meadows, S124).

* * * *

On May 7th, 1996, Utah Partners in Flight plan migratory bird watching in City Creek Canyon (Salt Lake Tribune). On May 7th, 1910, the Salt Lake Telegram published a photographic spread on City Creek Canyon and extolled the canyon’s virtues. The Telegram argued for a City Commission proposal to widen the road using prison labor and to make other park improvements (id).

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