City Creek Nature Notes – Salt Lake City

July 11, 2017

July 6th

Dry Fork Canyon

3:45 p.m. It is the third day of 100 degree Fahrenheit heat as I return to the Bonneville Shoreline Trail behind the University of Utah Hospital. I plan to jog up Dry Fork Canyon at the southeast end of the Salt Lake salient and then west along the Shoreline Trail above the Avenues. The Trails goes up Dry Fork for about one mile, crosses a pass, and then traverses a series of gullies that come down from the ridgeline to the Avenues and city below. The Trail begins in a invasive Cheat grass sea that is typical of the city’s foothills. Here, small light brown House crickets (Acheta domestica), another non-native, infest the Cheat grass. There are twenty or thirty per square yard. I round a corner into Dry Fork Canyon, and quickly its narrow walls close in and shade the canyon. The Fork’s walls are covered in dense Gambel’s oak forest, and this forest broken higher up by fields of the brown sun-dried husks of Arrowleaf balsamroot (Balsamorhiza sagittata). In an example of color adaptation, at the base of the oaks, larger, unidentified grasshoppers live, but unlike the sun-exposed crickets, these are colored green in order to better blend in with their surroundings.

At a seep one-third of a mile up canyon, there is a mini-oasis. In ten feet with Wood’s rose bushes on either side, Common sulphur butterflies, Western tiger swallowtail butterflies, small bluet dragonflies, Common whitetail dragonflies, Western Yellowjacket wasps, and Circumpolar bluets, all compete for space and landing rights around a small ditch of shallow water.

Further up canyon, the oak forest comes alive with sounds of birds: Black-headed grosbeaks, Lazuli buntings and Song sparrows call from the oaks spaced perhaps 100 feet apart on both canyon walls. Their songs are clear and strong, and I estimate there are about 250 birds between the canyon mouth and the upper pass. Unexpectedly, this density exceeds that of the stream areas in City Creek Canyon. The birds here, unlike in the City Creek Canyon, are fearless. I am able to stand only five feet from a Lazuli bunting as it tilts its head back to make a song. I am able to make a good recording and spectral graph. I flush two California quails (Callipepla californica) from the brush.

House crickets may explain the high density of birds in Dry Fork Canyon, where as the name implies, there is no water. Assuming a cricket weighs about one-quarter gram (0.000551 lbs), then there are about 85 tons of cricket mass on the city facing foothills between Dry Fork Canyon and the peak at the top of North Terrace Hills Drive in Valley View Canyon (see June 10th) (3,097,600 square yards per square mile x 4 miles x 1.25 miles x 20 cricket per square yard x 0.000551 lbs. per cricket divided by 2,000 lbs. per ton). The crickets exist at a similar density for another ten square miles between Memory Grove in lower City Creek Canyon and milepost 3.5 above Bonneville Drive. This suggests that there may be about 300 tons of these non-native crickets, and this is more than enough to support the summer bird populations seen in Dry Fork and City Creek Canyon.

As the canyon dries out, purple Bull thistles (Cirsium vulgare) covered with small black ants, a blue-white thin-petaled Eaton’s aster (Aster eatonii a.k.a. Symphyotrichum eatonii), and invasive blue Chicory (Cichorium intybus L.) grow. The roots of Chicory are roasted and ground to make chicory coffee. The white-topped weed Hoary cress (Cardaria draba) is also found.

As I near the upper Trail pass out of Dry Fork, I count two Broad-tailed hummingbirds, and just before the pass, I am treated to a rare display by a pair of Black-chinned hummingbirds (Archilochus alexandri). The male has trapped a female hummingbird at the base of Gambel’s oak sapling. For several minutes the male does its pendulum mating dance. It rapidly flies back and forth in a figure-eight pattern about six feet across, its wings buzzing loudly. Then the male gives up, and he does two high speed runs over the female while making a zinging noise. At the pass out of Dry Fork, I am greeted by expansive views of the city and of the Great Salt Lake, fifteen miles in the distance. The Sun is pounding, but my spirit soars from both the views and the hummingbird’s display.

* * * *

Per Thoreau’s “Journal” on July 6th, 1851, he walks by moonlight and again sees it reflected in water. He notes crickets sing with a different frequency at night. On July 6th, 1852, he hears a pewee and a red-eye. He sees tufted vetch, a fern, a tansey, and a parsnip. He watches a pickerel in a stream. He hears a duck on a pond. On July 6th, 1856, he stumbles on a peet-weet with its nest and young. On July 6th, 1858, he hears and sees loons. On July 6th, 1859, he describes heart-leaf.

* * * *

On July 6th, 1905, the City passed Councilperson’s Woods proposed ordinance banned automobiles from City Creek Canyon. On the same day, the Salt Lake Tribune urged that the road should be sprinkled with oil to keep dust down. Also on July 6th, 1905, the City Council held a heated debate on whether a bridge should be constructed over City Creek Road in support of the Commercial Club’s proposed scenic boulevard (Salt Lake Tribune).

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June 27, 2017

June 26th

Wasp Explosion and Return of the Water Striders

4:30 p.m. It reaches 100 degrees in the valley; the estival heat has returned. The stream level continues to decline, and the pond at picnic site 5 is beginning to reform under the higher spring run-off. At its banks, a wetted sand and silt line has developed. Here, about fifteen Western Yellowjacket wasps land and take sips of water. In a small pocket of calm water, the season’s first water strider (Aquarius remigis) appears (Sept 12th). A similar scene is found at the water seeps below picnic site 6. Checking the stream and its opposite banks at several times along the first mile, I find areas with thirty or forty Yellowjackets. One one bank,a Western tiger swallowtail butterfly lands also seeking to take a drink. Individual Yellowjackets start dive bombing the swallowtail, and after the fourth, the butterfly move down canon. What the yellow jackets are eating is unclear. I find one crawling over a roadside weed that no longer has flowers. It crawls to the juncture between a leaf and the plant’s main stalk where a white liquid oozes out. The wasp spends a minute drinking before flying off. I estimate that there are about 400 wasps along the first mile of road: enough for two colonies. At picnic site 1, a Prairie rose (Rosa setigera), a cultivar, with delicate pink blossoms that surround fifty stamens, blossoms.

Another insect explosion begins. On Utah milkweed plants, a black, yellow-stripped flower loving borer beetle (Calloides nobilis var mormonus Schaeffer) is found. Several are along the road, either feeding on pollen or hovering in flight.

* * * *

Per Thoreau’s “Journal” on June 26th, 1853, he notes that air is warmer after a thunderstorm. He describes a summer sunset and a faint afterglow three minutes after the sun falls below the horizon it lights up low clouds in the sky. He notes how in summer light, the outlines of mountain ridges are more distinct. On June 26, 1856, he describes the last remaining Native American, a seventy-year old woman, who lives alone in his neighborhood.

* * * *

On June 26th, R. J. Robinson, a consulting engineer who obtain water rights in City Creek Canyon, offered to sell his rights to the City (Salt Lake Tribune). On June 26th, 1908, the Salt Lake Tribune reported that Chin Wo, who had been sentenced to the City Creek chain gang road crew for vagrancy and who was believed to have mental health issues, attacked police guard Kast with a shovel.

June 25, 2017

June 25th

Fishing spiders

5:00 p.m. The first mile of road has turned into a green tube, and the garland of butterflies described on June 15th and June 22nd continues. The sky is clear and the air calm. Trees overhang above and views of the stream are obscured by thick underbrush except at picnic sites. The stream can also be accessed at small breaks made by anglers or at small natural breaks. There about ten of these breaks along the first road mile. I force myself through several of the breaks and look down to enjoy the cool, transparent stream. At each I find various types of spider webs: disordered tangle webs, sheet webs hung low just above the waterline, and the circular webs of Orb weaver spiders (Araneus sp.). Paradoxically, I see no spiders today, but their webs are full of hapless arthropod victims.

Lining the stream banks at these breaks are Bittersweet nightshade plants (Solanum dulcamara) a.k.a. Climbing nightshade with deep blue blossoms. These plants hug the stream’s steep banks and vertical rock retention walls, and they grow just above the waterline. At a few places along the first road mile, they incongruously protrude from the understory of serviceberry bushes (Amelanchier sp.), and there they are noticeable because their colorful blossoms are one of the few flowering plants that are left after the spring flower explosion. The Nightshade’s blossoms are either shriveling or extend vibrant yellow cones surrounded by blue petals. In the fall, these will yield bright red fruit.

Looking up from the stream and into the thick green sub-story, there are butterflies everywhere. They are the usual suspects for a canyon spring and early summer: Cabbage white butterflies, Western tiger swallowtails, Mourning cloaks (Nymphalis antiopa). These are now joined by White Admiral butterflies and by Common whitetail dragonflies patrolling overhead. I am used to seeing this floating butterfly assemblage traveling linearly on their feeding searches along bushes on the road’s sides, but here they fly in their natural setting. The butterflies follow large spiral flight paths broken by and traveling through the dense shrubs. In this setting, their frenetic sharp turns and chaotic shifts are necessary to navigate this complicated scene, and this explains these seemingly purposeless motions on their flights over the road. In this manner, the butterflies explore every possible hiding place in which a flowing blossom might be found.

At each of my stops along the stream, I see about five butterflies, and together with butterflies along the road, I estimate that there about 100 butterflies in the first mile road. Two Painted Lady butterflies (Venessa cardui) are also patrolling the roadside bushes. What flowering plant these butterflies are searching in the shurb understory is a mystery. The daytime flowering blossoms of spring are past, and only a few Foxglove beardtongue flowers remain open producing nectar. The only substantial flowering plant left is Yellow sweet clover. But the stands of this weed that line only the roadsides are fading, and on any one plant only one-third of the blossoms found at their peak are viable.

The fierce post-solistice sun begins to affect tree leaves. One or two Gambel’s oaks and Norway maples have a brace of leaves that are browned and shriveled at the edges. Once damaged, their leafs curl up, and the crabapple tree at the upper end of Pleasant Valley near mile 1.7 shows similar signs of stress. But the deciduous trees’ principal defense against the loss of water from heat and sunlight is a waxy layer on the upper surfaces of trees. This is best seen on the leafs of the western River birch trees. At the right angle to the Sun, their canopy flashes dappled green light for leafs titled away from the light and a blinding silver-white light for those at appropriate angle of reflection. University of Sussex ecologist Hartley notes that the waxy layer provides another benefit: it is some tree’s defense against caterpillars (Hartely 2009). Although caterpillars have evolved specialized feet to grasp leaf surfaces, caterpillars have a hard time walking over the wax layer, they fall off, and the plant is preserved. This may explain the caterpillars sometimes found along the road in the last week. I had supposed the caterpillars had crawled onto the roadway, but perhaps they have slipped and fallen from above.

Returning down canyon from milepost 1.5, insects are backlit by the Sun, and this makes them easier to see. At mile 1.1 near the entrance to lower Pleasant Valley, 30 to 40 Common whitetail dragonflies are circling between 50 and 100 feet above ground. Between the road surface and fifty feet, there are none. In cool places beneath the shade of trees, the prey of the dragonflies, groups of up to 100 gnats float. A small, immature desert tarantula (Aphonopelma chalcodes) scurries into the bushes.

Also mile 1.1, I hear raptor screams, and this repeats my earlier experience of June 21st. They are the unmistakable calls of two Peregrine falcons (Falco peregrinus). This time I travel back up canyon to get a better view, and below the eastern canyon wall near mile 0.8, more than a quarter-mile away, two peregrines are driving a smaller bird away from the canyon sides. There loud screams travel coherently through the calm summer air. This may be where the peregrines are nesting this season, but that side of the canyon does not have the steep cliffs found on its western walls. I note to watch this area closer to see if a nest can be confirmed.

* * * *

Per Thoreau’s “Journal” on June 25th, 1852, he sees a rainbow in the eastern morning sky. He opines that younger birds are duller in color in order to protect them from predators. He hears a bobolink and a golden robin. He sees wild rose and butter-and-eggs. He notes that in cool air, the ridges on distant mountains are more distinctly seen. He describes a moon-light walk. On June 25th, 1853, he finds two bushes of ripe service berries and associated cherry birds. On June 25th, 1854, he sees a bittern. On June 25th, 1858, he sees two or three young squirrels playing. He observes how objects including grass and water skimmers cast lenticular shadows on the bottom of a river. He again notes how the lighter undersides of leaves illuminate dark sprout forests.

* * * *

On June 25th, 1946, City Water Commissioner D. A. Affleck closed all lands in lower City Creek and above 14th Avenue to entry in order to prevent the possibility of grass fires (Salt Lake Telegram). Campfires were prohibited in upper City Creek Canyon (id). On June 25th, 1913, City officials plan to inspect the headwaters of Salt Lake valley canyons for water purity as part of a plan to develop more water sources (Salt Lake Telegram). On June 25th, 1896, new silver and lead ore bodies were discovered in upper City Creek Canyon about one mile from the old Red Bird Mine on Black Mountain (Salt Lake Herald). Mining work continues at other mines in the Hot Springs mining district, which includes City Creek (id). On June 25th, 1892, an old, destitute woman who had been living in cave in City Creek Canyon was sent to the hospital (Salt Lake Times).

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 13, 2017

June 6th

Sufficiency and Necessity

5:00 p.m. It is the fourth day of near record heat in the nineties. On the heat of the afternoon, only a few birds are heard: Warbling vireo, Black-headed grosbeak, Song sparrow and American robin. There is one each of this season’s common butterflies: Weidemeyer’s Admiral butterfly, Western tiger swallowtail, Mourning cloak butterfly, and Cabbage white butterfly. Because of the heat, there is no one on the first mile of road, although the parking lot is three-quarters full.

Returning down canyon, an American robin alights in the grass of a picnic site, cocks its head to one side, and then jabs down with its bill to pull out a fat earthworm. It comes and goes in a moment.

* * * *

In Thoreau’s “Journal” on June 6th, 1852, he notes the season’s first dragonflies. On June 6th, 1853, he records pink corydalis and side-saddle flowers, He sees blue-eyed grass, a flower, in meadows, lambkill, and huckleberries. He describes a slippery elm and hears bluebirds singing. He notes that under the summer sun, the ground is drying out and notes which spring flowers have peaked due to lack of water. On June 6th, 1854, he smells locust trees. He sees a viola by a river and examines the shapes of leaves of various trees. He again reports dragonflies and Sphinx moths. On June 6th, 1855, records seeing blue-eyed grass blooming. On June 6th, 1856, he admires that bird’s nests are well constructed. On June 6th, 1857, he notes leaves and grass dominate, i.e. not flowering plants. He notes dwarf dandelions are common. On June 6th, 1860, he notes that undergrowth foliage is becoming dense. At night, he observes bats in the sky and water bugs on a stream.

* * * *

In a 1995 article, Montgomerie of Queen’s University and Weatherhead at Carleton University conducted a series of controlled experiments concerning the most common of human experiences – seeing a robin pull of worm from underneath the ground. How do robins so expertly perform this task? It seems as if they can somehow see beneath the ground to locate their prey. I like their study because it nicely illustrates how proof of causation can be shown in laboratory controlled experiments and how designing such experiment is a difficult art. Such causation proofs are done using bi-directional “if and only if” implication, and such logic problems are the bane of graduate school candidates who sit for standardized entrance exams.

Montgomerie and Weatherhead suspected that robins use either sight, smell, vibrations, sound or some combination of the four to locate underground worms. In their experiments, Montgomerie and Weatherhead measured the success rate of robins finding mealworms in four artificial environments: First, live scent, sound, and vibration emitting mealworms were buried in the same cage as smell emitting but soundless and vibration-less dead worms. Second, robins were placed on a layer of soil that contained a buried cardboard sheet that covered soil containing live mealworms. Thus, the robins could not rely on visual cues to find their prey. Third, they buried mealworms in a vertical soil containing wall of a cage. Thus, the robins could not feel the vibrations of the buried worms. Fourth, they placed robins on soil containing buried live mealworms but used a white noise generator to mask any noises that the worms might make. The robins could find worms in the absence of sight, smell and vibration cues. They had less success when finding buried worms when sounds were masked with white noise (id).

Proving causation by bi-directional “if and only if” implication involves showing that cause implies effect using propositional logic, that is “If a (C)ause exits, then the (E)ffect occurs” or C -> E in symbolic logic. In bi-directional “if and only if”, the (E)ffect must also imply the (C)ause, or E -> C. The C -> E part is usually described using the language that “C is a sufficient cause for E”, and the E -> C part is described using the language “C is a necessary cause for E”. The mathematics of propositional logic tells us that C -> E is the same as not(C and not E). Conversely, E -> C is the same as not(E and not C). Thus, E -> C, sufficient causes and necessary causes can be expressed as an overlapping butterfly Venn diagrams. Draw two overlapping circles and label the left circle “C” for causes and the right “E” for the effect. Sufficient causes are in the left circle, and necessary causes are subsets of the effect and appear within the right circle. Necessary and sufficient causes appear in the overlapping area. All of this confusing propositional logic is normally reduced to two simple tests for the propose of analyzing causation and taking graduate school entrance examinations:

• Sufficient cause test: Any candidate Cause that is present when the Effect is absent is eliminated as a candidate sufficient cause. This is equivalent to not(C and not E) in proposition logic symbolism.

• Necessary cause test: When an Effect is present when a candidate Cause is absent is eliminated as a candidate necessary cause. This is equivalent to not(E and not C) in proposition logic symbolism.

• Necessary and sufficient cause test: Is the intersection of the remaining results after application of previous two tests.

Finding a necessary and sufficient cause is accomplished by building a table of causes and the resulting effect. Eliminate causes that fail either the sufficient or necessary causation test and take the intersection of the two lists. The remaining candidates are sufficient and necessary causes. The proof that those candidates are the cause of the effect is done. This is best illustrated by Pasteur’s experiment that demonstrates that the fermentation of liquids like grape juice and milk was caused by particles in the air and did not arise spontaneously from particles in those liquids. This was Pasteur’s proof of the germ theory of disease.

To prove that particles in the air causes liquids to ferment and not particles in the liquid, Pasteur constructed flasks with a long-thin neck. Potential causes of fermentation are air in the flask, air in the liquid, and air outside the flask. In his first test, he heated the grape juice (or milk) to destroy any bacteria in the milk and the long-neck excluded outside air. The liquid did not ferment. The result where fermentation is absent shows under the sufficient cause test, that neither particles in the liquid or in the flask’s air cause fermentation. That left the air outside the bottle as an untested candidate sufficient cause. In his second test, he again heated the liquid and air inside the flask to kill all bacteria, but then broke off the long neck that excluded outside air. The liquid fermented. This result where fermentation effect is present shows that under the necessary cause test, air outside the flask contains particles that cause fermentation, but not the sterilized air or liquid in the flask. In his third test, Pasteur heated a tilted the flask so liquid filled the long neck, exposing only the liquid to outside air. Fermentation occurred, and under the necessary cause test, this excluded the air inside the flask as a necessary cause of fermentation. The intersection of the candidate sufficient and necessary causes is the air outside the flask. Conversely, fermentation does not occur spontaneously from particles in the air or liquid inside the sterilized flask.

Applying this type of causation proof to how robins find worms, Montgomerie and Weatherhead thought that there were four candidate causes or means by which robins found worms (the effect): smell, vibration, sound or vision, or some combination of the three. The effect is present when birds found the worms and absent when they did not. In their first experiment involving scent, birds were no better at finding dead worms than chance or than finding live worms, and under the sufficient cause test, this eliminated smell as a sufficient cause. The birds did much better than chance in finding live worms using the remaining auditory, visual or vibration cues, but since smell was also present, no candidate cause was eliminated under the necessary causation test. In their second experiment that removed visual cues but left smell, vibrations and sounds, the birds found live worms better than chance. Under the necessary test, eliminated sight as a necessary cause. In their third test involving vibration, birds were still able to find worms when only vibration was removed, and vibration was eliminated as a necessary cause. In their fourth test, birds were unable to find worms when only sound was removed, and smell, vibration, and sight were eliminated as a sufficient causes. The necessary and sufficient results of their four tests can be reorganized as follows:

• Smell – Effect absent – sufficiency test: Smell-possible, Sight-impossible, Vibration-impossible, and Sound-impossible. Result: Smell was eliminated as a candidate sufficient cause.

• Sound – Effect absent – sufficiency test: Smell-possible, Sight-possible Vibration-possible, and Sound-impossible. Result: Smell, Sight and Vibration are eliminated as a candidate sufficient causes. Sound remained as a candidate sufficient cause.

• Sight – Effect present – necessary test: Smell-possible, Sight-impossible, Vibration-possible, and Sound-possible. Result: Only sight was eliminated as a necessary cause.

• Vibration – Effect present – necessary test: Smell-possible, Sight-possible, Vibration-impossible, and Sound-possible. Result: Only vibration was eliminated as a necessary cause.

• Smell – Effect present – necessary test: Smell-possible, Sight-possible, Vibration-possible, and Sound-possible. Result: This test eliminated no candidate necessary causes.

Looking at the intersection of all of these tests, only sound remains as both a sufficient and necessary cause. Thus, Montgomerie and Weatherhead concluded that, “[T]hese results strongly suggest that the robins located buried mealworms and earthworms by using auditory cues (id. at 149). Their conclusion varied from the only similar prior study that concluded that robins use visual cues to find underground worms.

For most questions involving nature (and economics and sociology), causation cannot be shown in controlled experiments, and investigators must rely only on statistical proof of sufficient causal agents. Both necessity and sufficiency can never be shown due to the multiplicity of causal factors, from ethical restraints that prevent the use of controlled experiments, or excessive cost, and proof of causation is relegated to argumentation from signs (April 27th). For such matters we are forced to rely on humanistic-based judgments when issues involving nature and biology have implications for human society. Much of modern political argumentation is based on politicians intentionally citing only one of several candidate sufficient causes, and then questionably ignoring other obvious, likely causal factors in order to fashion a passably convincing position. The only antidote is an educated citizenry armed with critical thinking skills.

When our canyon robin cocked its head to one side today, it was listening for the buried worm.

* * * *

On June 6th, 2009, three-hundred volunteers pulled invasive weeds like myrtle spurge and toadflax from the Morris Reservoir area overlooking City Creek Canyon (Salt Lake Tribune). On June 6th, 1993, the Salt Lake Tribune overviews hiking access points along the Salt Lake Valley, including at Ensign Peak, City Creek Canyon, and the Tomahawk Drive access to Little Twin Peaks in the Avenues. The Tribune notes reductions in hiking access as luxury subdivisions, such as the Turville-Robinson development below Ensign Peak, develop the foothills. Salt Lake City has regulations requiring foothill developers to include access points in their plans. On June 6th, 1905, boxer Jack O’Keefe trained by running up City Creek Canyon (Salt Lake Herald). On June 6, 1904, wildflowers are in full bloom on the foothills and in the canyons (Salt Lake Herald). City Creek has Stansbury’s phlox, that has a purple flower and yellow balsam root (id).

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 29, 2017

May 28th

It is enough. This is the Right [Natural] Place – Part VI – Future Population Growth

5:30 p.m. I have misjudged the reopening of the road; it has opened to traffic today, but only a few cars come through the gate even though it is a beautiful blue-skied day. The road will also be open to cars tomorrow, Memorial Day. From the gate to mile 0.2, Warbling vireos sing, and I get a Black-headed grosbeak to respond to my playing of bird song audio recordings. When I return down canyon an hour later, a female Yellow warbler is at the top of what I now calling “Perching Tree”. The Perching tree is below picnic site one; it is about 40 feet tall; but the last 15 feet of its vertical branches are bare. Various birds like to perch there in the warm evening sunlight (May 19th, Lazuli bunting; May 23rd, Western tanager). The perch gives the birds a clear view of the surrounding landscape, and although it exposes them to attack from the hawks above, the bare branches prevent other birds from approaching unseen from below. Near picnic site 3, a Chirping sparrow, a Song sparrow and a House finch are heard.

In this lowest part of the first mile road, the blossoms of red ozier dogwoods and chokecherry shrubs are failing or are closed. The leafless ovaries are swelled and pregnant. At picnic site 3, blossoms on one dogwood are three-quarters gone and the remaining one-quarter is mobbed by a one-hundred nectar drinking 1-2 millimeter flies. But further up canyon at mile 0.7, the red ozier dogwoods are still in full bloom. As with the chokecherry, the pregnant ovaries have swelled in preparation for seed making. At the seep around the bend from picnic site 6, a cattail has grown to six feet high. Near the Red Bridge, a Box Elder tree is festooned with this season’s new catkins, full of seeds. Near mile 1.1, Wild geraniums are smaller than those found lower at mile 0.2, and there is a strain of white, not purple, colored blossoms at this higher and drier site.

Near mile 0.4, there is a small grove of new horsetails whose top buds are fully expanded. These horsetails appear different from the predominate variety in the canyon. They are larger in diameter and light, instead of dark green in color. When I tap one with my finger, it gives off small clouds of dense white spores. That horsetails give off spores means that they reproduce asexually and not sexually through seeds. Other horsetails in the canyon do not have these new season buds. Horsetails are primitive plants that originated in the Devoian period about 400 million years ago.

At the tunnel seep below picnic site 6, there is a small brown butterfly with a black pattern along its leading wingtips. It is a Sleepy duskywing (Erynnis brizo burgessi). About eight others are spread out along the first mile. At mile 1.1, they are joined by a single Yellow swallowtail butterflies and a lone Red-rumped central bumble bee. Near mile 0.6, a diarrhetic bird was laid a series of thick spots on center of the road, and a Stink bug is busily cleaning up one by feeding.

Near mile 1.1, eight unidentified large raptors are circling about 300 feet overhead and around the meadows on the south-east Salt Lake salient. They are too high for identification. They are black from above, have a black body with dark tails, but their trailing underwings are a dirty white with black leading edges. The beak is not raven or crow-like. That they are flying high is good, for I hear loud chirping coming from underneath the shelter of a nearby low plant whose broad leafs are about 12 by 18 inches wide. It is a mallard chick. As newborns, mallard chicks look like their mothers. They have a brown back and a brown eye-strip across a light brown-yellow face, but their breast feathers are a lighter yellow. This chick appears lost. It clutch-mates are not near as it moves from underneath its hide and pathetically sits in the open. The chick sees me as a large parental figure and wants me to help. As I regrettably leave, I can only hope that its mother is gathering food in the nearby in the stream and that she will return before a predator finds her young. I also hope by leaving that the chick’s protective instincts will reassert itself, and the young bird will return to wait quietly underneath its leafy hiding place.

After some research at home, I find that my “raptors” are not raptors after all. They are Turkey vultures. Turkey vultures eat only carrion and not eat live prey. The mallard chick was safe from them. This is a beginner bird identification mistake.

* * * *

On April 6th and 7th, I alluded to how the Mormons have many important choices to make regarding the canyons of Salt Lake valley, including City Creek Canyon. Many of these will be population driven. On the one hand, Mormon Utah has a propensity to have large families, and this creates high pressures for rapid development, and that might lead to increased demand for developing water, the evaporation of the Great Salt Lake (May 27th), and decline of bird populations (May 26th). Other meta- or mega-trends suggest an opposite course. Although the Earth is on a path to add 3 billion more persons and to reach by 2050 a global population of between 8.5 and 13 billion persons with a mean forecast of about 10 billion persons. A mega-trend for all developed countries and developing countries except Africa is that the total fertility rate has declined below the sub-fertility replacement threshold (United Nations 2015). This includes China, the United States, the Russian Federation, Japan, and Germany. This means that their populations will decline in the future and that future populations will age and that and capitalism, which has been rooted in ever expanding markets, must adapt to negative yields. Early effects of this are seen in Japan, which elected to not permit the importation of foreign workers, and that decision was one cause of Japan’s stagnant economic growth since the 1990s. Capital, fearing Japan’s negative growth population structure and hence negative yield outlook, has been flowing out of the country. The United States and the European Union responded differently by, in the case of the United States allowing massive illegal immigration, and in case of the European Union by having large legal guest worker programs.

In the United States, Utah is an exception due its Mormon heritage. In 2014, Utah’s total fertility rate is 2.33, or about 0.5 higher than the national average of 1.86 (Perlich 2016). But even Utah’s rate continues to decline as rapidly as the nation’s, and in the near future even Utah may drop below replacement fertility of 2.1.

These general population trends for the global, for the United States, for Utah and the canyon suggests several alternative long-term outcomes for recreation use in City Creek and the other Salt Lake valley canyons. The trend also has implications for public support for their continued preservation as a natural areas. In one scenario, the global population continues towards the 10 billion forecast and Utah’s population continues to age. As Utah has more older citizens, they will be less able or interested to take long weekend journeys for outdoor recreation. They will become more interested in preserving areas like City Creek and the other Salt Lake valley canyons in order to have an adequate supply of nearby outdoor recreation opportunities. Second, the United States could embark on a massive immigration program in order to sustain the historical population increases on which modern capitalism demands in order to maintain positive investment yields. In that case, continued population growth will fuel the demand for more water in the Bear River Basin and more land development in the nearby canyons. Third, population trends could move towards the high end the United Nations’ forecast of 13 billion persons by 2050. The result in Utah would be the same as in second scenario.

Faced with such uncertainty, government could decide to either make plans with definite functional objectives on the state of the future environment or make, what I call “non-plan” plans. In a non-plan plan, governments merely state that they meet their minimum legal obligations, e.g. – constraints imposed by the Endangered Species Act – and that the governmental entity will study issues as the baseline state of the social, economic or physical environment changes. Most of the governmental plans previously discussed, such as the 2013 Utah Department of Natural Resources Great Salt Lake Management Plan or the recent draft Salt Lake County Resource Management Plan fall into the “non-plan” plan category (Salt Lake County 2017). The other approach is to define functional objectives or desired states, and the 1986 Salt Lake City Master Plan for City Creek is an example, e.g. – the City will operate the canyon as a natural area. A consequence of ambiguous plans is that clear signals are not sent to stakeholders, and the price of such plans is that instead of having stability, citizens must remain vigilant against never-ending attempts by better funded development interests to revisit previously settled matters (April 28th).

* * * *

On May 28th, 2010, the City announces that it will close City Creek Canyon while helicopters spray the herbicide Milestone on the Starthistle infestation at City Creek Canyon (Salt Lake Tribune). (From 2011 to 2017, the City will hand spray Milestone on selected small areas of about 20 acres.) On May 28th, 2008, Samuel Stewart announced that he would host President George Bush at his home overlooking City Creek Canyon in order to raise funds for John McCain’s presidential race (Salt Lake Tribune). On May 28th, 1881, the Union Pacific and the United States will survey City Creek Canyon (Salt Lake Tribune). The Union Pacific owns a federal land grant of twenty-miles of land on either side of the railroad in Morgan County interspersed with Forest Service sections, which includes parts of City Creek (Salt Lake Tribune).

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 19, 2017

May 19th

Sun Dappled Stream and Butterfly Hosts

5:15 p.m. The first mile is almost fully leafed-out and the understory is well-developed. The stream, which throughout the winter is fully visible, can now only be caught in partially obscured glimpses where the trees and underbrush break. Through those screens, the low, warm, yellow light of the falling Sun glides and lands on clear surface of the stream in round dapples. Today is an advance hint of the stream during the summer canyon summer which is now one month away. The key today difference is the stream runs high, but like the summer it has turned transparent. The stream has fallen about four inches overnight, but the water is pure. The spring period in which the stream runs, according to the City’s 1895 Mayor Baskin, as “very muddy, unwholesome and unpalatable water” (Feb. 6th) has passed. Rocks can clearly be seen through the rushing waters between its windowed surface.

It remains unseasonably cold – in the low fifties in the canyon and near freezing overnight – from the passage of the last storm. People in the city complain about it constantly having wearied of prior long winter season, and in the canyon, this has emptied the road. The cold has also suppressed the birds and the butterflies. A lesser total of 15 birds are heard along the road and the Pipeline Trail. Only a single Western tiger swallowtail and some gnats make an appearance.

A single Red-tailed hawk floats one hundred feet over the parking lot. At picnic site 1, my evening Lazuli Bunting is perched on the tallest tree. Along the Pipeline Trail using audio recordings and spectrograms, I am able to identify the songs of three of the some ten song birds, i.e. – a , a Warbling vireo, and a bleating evening “keah” from a Northern flicker. I have begun to make some progress into understanding the canyon birding soundscape (May 6th).

When the butterflies rally in next week’s rising heat, what will the adult butterflies and their caterpillars eat? I can find nothing specific for Utah, and therefore, using sources for other States, I compiled a list of possible hosts and food sources for some of the recently seen butterflies. It is a starting point, suggestive, and not authoritative. Although the butterfly spring peak has passed, I will have to take better notes on which butterflies are associated with which plants.

List of Possible Plant Hosts for Butterflies and Their Caterpillars in City City Creek Canyon
• Mourning cloak butterfly. Adult: Tree sap from Gambel’s oaks. Willows, elms, maple and ash trees. Caterpillar: The same plus aspen and river birch.

• White cabbage butterfly. Adult: Nectar from mustards, dandelion, asters, clovers and mints. Caterpillar: Same. There are various analogs to these plants in the canyon.

• Painted lady butterfly. Adult: Yarrows, thistles, sagebrush, sunflowers, milk-thistle, stinging nettle. Caterpillars: Same plus milkweed.

• American lady butterfly. Adult: Sagebrush, thistles, Wood’s rose and vetches. Caterpillar: Sunflowers, burdock, milkweed and aster.

• White-lined sphinx moth. Adult: Nectar from columbines, larkspurs, clovers, and thistles. I have seen Giant sphinx primary feed in the spring on dandelion. Caterpillar: apple and elm trees.

• Spring Azure. Adult: Dogwood, and berry plants.

• Common sulphur butterfly. Adult: Clovers and vetches and nectar from many plants. Caterpillar: Clovers and vetches.

• Sara Orange Tip butterfly. The Sara Orange tip is similar to the Julia Orangetip butterfly (Anthocharis julia browningi). For the Julia – Adult: Flower nectar from rock cresses, violets, and mustards. Caterpillar: Rock cresses.

Source: Dallas County Lepidopterists’ Society (2008). Host Plants by Butterfly (Web).

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University of Utah Meteorology Professor James Steenburgh recommends a new climate change application to examine whether local daily weather patterns are unusual. People tend to mid-interpret unusual cold and hot seasons as indications either for or against the existence of global warming, regardless of the separate issue of whether it is human-caused or not. The University of Maine and its Climate Change Institute has deployed an internet application that shows each day, a map of the globe and how surface temperatures at each point on the Earth differs from the average temperature at that point for that day over the last seventy years (University of Maine 2017a). A large dark blue spot on the map hovers over Utah, Colorado and Wyoming, indicating that the Intermountain West is 18 degrees Fahrenheit cooler that normal. The coldspot sits in the cradle of a “U” shaped dip in the jet stream. Overall, the globe is about 0.5 degrees warmer. The lesson to be learned from the map is even when their are local anomalies in weather, such as in the canyon today, the world average remains steady. The world average is the indicator of global warming and not local conditions.

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On May 19th, 2008, the City closes City Creek Canyon to spray herbicides on the invasive Starthistle plant (Salt Lake Tribune, May 20, 2008). On May 19th, 1906, the City tankman and former city councilman George D. Dean, was found dead at the Water tankman’s house in City Creek Canyon (Deseret Evening News, Salt Lake Tribune, May 20th, 1906). On May 19th, 1875, seminary students went picnicking in City Creek Canyon (May 19, 1875).

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