City Creek Nature Notes – Salt Lake City

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).


December 22, 2016

December 22nd

Filed under: Birds, Black-billed magpie, Microbes, Mountain Chickadee, Northern flicker, Robin — canopus56 @ 2:04 pm

Trophic Levels

11:00 a.m. It is cold and overcast again, but it has not rained or snowed for several days. The snow has condensed and lost two-thirds of its original volume. Between picnic sites 2 and 3, birds have congregated on flat lands near mile 0.3. A chorus of magpies, a flicker, a robin, and chickadees all call back and forth to one another. At mile 1.3, only magpie calls are heard.

Stripped of its distracting summer green and autumnal yellows, the canyon at winter rest is simplified, and its ecological layers are more easily seen. The first level consists of microscopic animals and prokaryotes above the surface, including as lichens and mosses (Dec. 6th), unseen microbes in the soil, and unseen microbes extending four kilometers below the surface (Baker 2016, Li-Hung Lin et al 2013) and within mammals and birds (Whittman 1999) represent a slightly less than the volume of biomass of visible plants above ground. In the second level, the productivity of plants dominates the visual landscape, in particular by Gambel’s oaks (August 30, August 31st). At the surface, the annual productivity is held in the layer of leaves underneath the snow, and that layer is primed with bacteria and fungi ready to turn the fallen leaves back into nutrients. In a third level, insects are probably the next most numerous and visible group in terms of size of zoomass, including gnats (August 11th, November 9th) and their predators, dragonflies (August 11th, August 29th). Finally, the small number of bird’s nests (Dec. 10th), deer (Oct. 23rd) and elk (Dec. 13th) seen in the canyon today attest to the small ratio of the mass of mammals and birds to the total mass of other living things in and beneath the canyon. That ratio may be as little as 1:1000 (Hartley 2010), but approximately 18 percent of plant biomass is consumed by animals each year (id.)

In Thoreau’s “Journal” on December 22nd, 1859, he observes watercress in the bottom of a stream. He notes empty chestnut burrs at the base of a tree where squirrels have collected, opened and removed the nut inside.

On December 22nd, 1883, Avenues’ homeowners held a mass meeting to oppose a plan by the newly incorporated Camp Douglas Railway Company to build a railroad from Red Butte Canyon for the purpose of hauling mined sandstone. The railroad was proposed to run along 4th Avenue, down into City Creek Canyon, and then to a railroad depot (Salt Lake Herald). At that time, the resident’s domestic water was not pumped into homes, but was drawn from public ditches that ran in front of their homes. They were concerned that the railroad would pollute their aqueduct water, endanger the foundations of their homes, be too noisy, present a traffic hazard for residents who then traveled mostly by foot, and was simply too large for the road’s width.

December 8, 2016

December 9th

Counting Nests

8:00 a.m. On December 8th, I completed an inventory of nests in the first two miles of the canyon done on December 1st through the 7th, and the results are not what I expected. I had thought that small birds would prefer to nest away from the road and expected to find more nests along the trails, but they predominantly nest close to the road and stream. I count thirty-nine nests in the first two miles. For insect nests, two are Paper wasp nests and six are Bald-faced Hornet nests. The remaining thirty-one are birds’ nests. Of the thirty-one bird nests: nine are delicately woven bag nests for small birds such as hummingbirds; four are hanging and finely woven grass nests suitable for small and medium sized birds; one is a cliff stick nest of the falcon pair; five are snag nests in drilled into hollow cavities of snag or dead tree trunks; and the remainder are circular or platform twig nests.

All but one falcon nest is along or adjacent to the paved road. Initially, I thought that there would be many small bird nests along the Pipeline trail in the scrub oaks, but there are none. Checking the trail a second time, I realize that the Gambel’s oaks on this west side of the canyon would be too hot in late May and early June for fledglings. Birds are nesting in the coolest part of the canyon, next to water. Mountain chickadees and Black-hooded chickadees both use snags for nesting and do not build twig nests (Hutto, p. 34-35).

There are many snags, i.e. – dead trees, in the first two miles of the canyon. In addition to the chickadees, the Hairy woodpecker (Picoides villosus) and the Northern flicker rely on snags for shelter and nesting (Hutto 34-35, Werstack, 49-50). At picnic site 7, a good example is in a 40 feet vertical snag on the other side of the creek. At its top is a tear shaped excavation that indicates there is a nest in the hollowed out tree. It is possibly the primary or secondary nest of the Northern flicker seen in this area. A second snag at the up canyon end of picnic site 9 has many smaller holes drilled in it, and these may be suitable for chickadee nesting. Birds prefer snag trunks between 10 inches to 14 inches for making a hollowed-out tree nest. In 2016, Werstack et al estimated that there are 149 million snags in Utah suitable for bird nesting, but I estimate that there are probably about 20 to 30 suitable snags in the first two miles of the canyon.

Where the Pipeline Trail skirts the based of cliffs on north side of the road near mile 1.0, a Peregrine falcon pair has a large stick nest. The nest is perched on a rock ledge about 300 feet from the trial. It cannot be accessed either from above or below by predators, and it is only faintly visible with the naked-eye. Binocular or a monocular magnification is needed to see any detail. Although the nest is currently empty, from April to June, I watched the pair and fledglings almost every day. Not in this survey, but seen last year, is a large circular stick nest in the top of an eighty foot fir tree near mile 2.4. That nest was occupied by a breeding pair of Cooper’s Hawks.

Goodfellow and Hansell describe the architectural skill that birds use to construct the many woven grass and smaller twig nests. When making hanging-basket grass or circular twig nests, some birds will use a hook technique similar to Velcro. As noted on September 5th, the design of Velcro was inspired by the burrs of the burdock plant. Birds also mimic the burdock burr. They choose twigs with small hooks near the ends or twist grasses to make hooks and as they weave a twig into the nest, they secure the twig by hooking the end around an earlier placed twig.

My instinct is that there are too few nests for the volume of birds seen during the March to May nesting season, but my bird count data suggests the number is about right. My birding log between March 2015 and May 2015 of last year (Fisher 2015) shows 166 bird sightings. Given that these involve resighting the same birds multiple times, 39 nests is reasonable. During the winter and spring, small Black-hooded chickadees, Mountain chickadees and Stellar Jays are the most prevalent bird in the canyon. Other birding logs made by Tracey Aviary professionals are stored at the Cornell University’s Ornithology Laboratory’s eBird database for the “Bonneville/City Creek” observing area (Cornell 2016). Are there and where are any missing birds’ nests?

Hornets were far more common than I had previously thought. A nest down canyon of picnic site 6 is notable. The late afternoon Sun makes it glow. It is twice the size of a basketball, and it precariously sits intertwined with the smallest upper branches at the top of a 100 foot tall Rocky Mountain cottonwood. The nest sways back and forth in the wind, but it is the most secure of the five hornet nests in the lower canyon. Although I see and photograph this nest

These hornet nests provide another link in the food chain. The hornets drink nectar and eat other smaller insects. In turn, hornets are the another food source for the many small birds seen in the spring in the first canyon mile.

In Thoreau’s “Journal” on December 9th, 1855, he visually observes his first owl in ten years, having only their heard their calls during that period.

October 6, 2016

October 6th

Battling Birds

10:45 a.m. A flock of Western Scrub Jays (Aphelocoma californica) have returned to the canyon, as revealed by their raucous screech call. On the north embankment of the road near Guardhouse Gate, one jay lands, picks up an acorn off the slope, throws it into the air above its head, and then expertly catches and swallows the falling nut. Like the flickers, the Gambel’s Oak acron are the scrub jay’s staple during the non-breeding season. Scrub Jays are one of the two prominent jays that pass through the canyon; the other is Stellar’s Jay (Cyanocitta stelleri). Both the western jay, Stellar’s Jay, and magpies are cousins in the family Corvidae.

Just northeast of Guardhouse Gate, the flock of Scrub Jays and the flock of Northern Flickers are having a heated discussion. Given that the Scrub Jays the more aggressive species, I suspect that they will get the best of the matter.

At mile 1.7 near the eastern end of Pleasant Valley, the Black-billed magpies (Pica hudsonia) have also returned. The Black-billed magpie is a commonly-seen over-wintering bird in urban Salt Lake City, and they are known for their obnoxious “wenk-wenk-wenk” screech. They are well-adapted both the city and their native open chaparral. Magpies are another bird for which I have a great deal of respect. They are highly intelligent and opportunistic. One winter, after leaving a window open, I discovered two them in the kitchen snacking on granola and three others exploring the house. They over-winter in Utah and seem to be impervious to sub-freezing temperatures that would kill a human within an hour, and despite being carrion eaters, they find adequate food during the winter. They are fearless of humans. Today, as I jog pass the mile 1.5, a magpie is sitting at the base of the 1.5 milepost sign with his back to the road. He or she only gives me a brief acknowledging glance as I stride by.

The meadow at mile 1.7 is a recuperating, open, and circular flat where a concrete reservoir used to sit. During the 2000s, the reservoir was decommissioned, like many older dams on the western urban slopes along the Wasatch Front range, out of concern that water retention structures would fail in a large earthquake. Trees circle the outside of the flat.

Today, a magpie flock is stretched along several trees on the far edge of the flat, and on the side nearest the road, a similar flock of Scrub Jays rest in a string of trees. At the tree dividing the two sides, a couple of magpies and jays are debating loudly. The magpies are larger than the jays, and they are more of a bully than their cousins. I suspect the magpies will win the discussion.

October 5th

Filed under: Birds, Blacked-Headed Chickadee, Guardhouse gate, Northern flicker, Places — canopus56 @ 12:39 pm

Fleeting Flickers

On September 27th, I noted how difficult it is for amateurs to identify insects because of their many varieties and stages of development, and the same is true for birds. But for birds, the reason is different: bird are impossible to see for most of year. They mostly live hidden in the foliage of trees, and only their calls can be heard. About ten days ago, the Northern Flickers returned to the canyon, and a few will over-winter here. I had forgotten their calls other the summer – a plaintive “squeechu” and a rapid-fire, repeating “kih-kih”. For a frustrating week, I caught brief glimpses of the responsible fowl, but there was never enough of sighting to make an identification. On another occasion while running along the Pipeline Trail, three, separated by about an eighth of a mile, could be heard making calls and responses.

On October 2nd while the weather was cold and wet, three flickers were huddling at the top of a 70 foot tree near Guardhouse Gate. A fourth was hidden in a tree and was calling to the others. Using a monocular, the good identification was finally made. The Northern Flicker is one of my favorites: it has a mottled, checkerboard belly capped by a black breastplate. These were the red-shafted form of the Northern Flicker whose under-wings flash red-brown in flight.

This experience reminds me why birds sing. Whether the Northern Flicker or the smaller Black-Hooded Chickadee, neither can see each other when in a leafed woodland. They must sing in order to locate each other. There is no other simple way for them to disperse for grazing, but still keep tabs on each other.

Former evolutionary biologist, co-founder of the idea of punctuated equilibrium, and popular author Stephen J. Gould (deceased 2002) would call this a “just so story”. It is a convenient narrative that fits the facts, but the truth is that there were no human alive an eon ago when forest-dwelling, feathered dinosaurs first decided to sing instead of hiss. We will and can never no the truth of the matter. One of the themes of Gould’s popular writings Gould was that just-so-stories often lead paleontologists and biologists astray and to incorrect conclusions.

September 29, 2016

September 29th

Filed under: Cricket, Northern flicker, People, Sounds, Stream — canopus56 @ 8:53 pm

The Sounds of Solitude

Noon at mile 0.5. Stream bubbles with random plonks and trickles. Crickets make a relaxing, rhythmic pulsation. Wind ebbs and flows through the trees, and it dislodges leaves that silently fall to the road. Wind whistles through spokes as a bicycle whizzes by. Crackling noises as leave are underfoot. Voices of couples walking and talking makes its own musical rhythm. Muffled footsteps of runners. A sole Northern flicker (Colaptes auratus) makes a plaintive cry seeking its mate. Joy ensues, and I seek out clumps of leaves just to listen to their crackling sounds as I sluff through them.

One of the most enjoyable experiences when jogging or walking in the canyon is the sounds. My favorite sounds come from the stream combined with the rhythmic pulse of the crickets. Today, both are loud because the stream is running higher from recent rain and the crickets now dominate canyon insect life. These sounds form a relaxing, meditative white noise. These sounds make jogging in the canyon a form of moving zen meditation.

The purpose of zen and other forms of mediation is discrimination, i.e. – the discrimination of the mind from the world, thus, freeing consciousness to fully appreciate the world as it is and not as the mind distorts it. Some choose to consider this as a religious and others as a psychological practice. However it is viewed, the experience of walking and jogging in the canyon is about quieting the mind and enjoying the natural surroundings. It is not about note-taking, observing, and writing about it.

At the portion of the road between mile 1.7 and 2.0, the stream makes the best noise. Here, the stream is immediately next to the road and is fast moving, but it has cut deep into a ravine that is in perpetual shadow. The plonk sound of water as it travels from pool to pool is particularly crisp and deep as it echos of the stream’s walls. At the coldest of winter and for just one week, this is the only part of the stream in the entire canyon that completely freezes over.

Paul Simon in his classic folk song the “Sounds of Silence” reminds us to occasionally be still and to look inward. The canyon produces sounds of solitude that also remind me to be still.

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