City Creek Nature Notes – Salt Lake City

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 28, 2017

May 27th

Will the Great Salt Lake Disappear? – Part II

5:00 p.m. Since city residents have driven to dispersed recreation parks far from the valley, the valley has emptied and there are few cars in the parking lot. In the pre-automobile era, they would come to the canyon during May holidays. In 1908, a newspaper reported that “thousands of people” spent the day strolling in City Creek (Salt Lake Herald, May 8, 1908). As car culture developed from the 1920s through end of the century, the canyon became less of a focus for city resident’s holiday outdoor recreation. An old postcard in my grandmother’s family album records how in 1927, my great-grandparents drove the new Lincoln Highway from Ohio to Salt Lake City in their new Ford Model-T, and then drove up the then open road to Sun Dial Peak and Lake Blanche at 9,500 feet. I like to nostalgically imagine that they also took a moment to drive up the canyon that I jog today.

But today, the canyon is almost empty. There are even fewer evening birds and along the first mile, I primarily hear the string of Warbling vireos interspersed with a few Song sparrows and American robins. The raptors are gone; butterflies are absent except for three. Woods rose that opened just a few days ago has begun to drop its leaves, but given the 100 rose plants along the first mile road, I believe more will open as the season progresses. Blossoms on the Solomon’s stars near mile 0.6 have grown from having only one or two blooms to having grown complex conical inflorescences. Arrowleaf balsamroot in the lower canyon has lost its blooms.

* * * *

Continuing population growth and their need for future water keeps the scenario that the Great Salt Lake might disappear completely in the next thirty years within the scope of reasonable probability. Salt Lake County grew from about 900,000 to 1.1 million from 2000 to 2014, or about twenty percent, and Utah County to the south grew from 370,000 to 575,000, or about fifty percent between 2000 and 2015. From this growth, Salt Lake valley and Utah County to the south are quickly exhausting the 250,000 new acre feet of water received in 2007 from the eastern transbasin Central Utah Project, and plans have been made to develop and transport another 250,000 acre feet of water per year from the Bear River basin to the north (Wurtsbaugh et al 2016; Utah Division of Water Resources 2004). Utah’s population is projected to reach 5.5 million by 2050. The lake is a substantial source of economic activity in northern Utah, 1.2 billion USD in 2010 (Bioeconomics 2010), and that also puts pressure on state managers to accommodate both industry, recreation and wildlife both to maintain and to decrease the lake’s level.

The changes in the Great Salt Lake and projections for increasing population and decreasing lake levels did not go unnoticed by government, and the competing interests of preserving the lake’s current level for wildlife and accommodating economic growth were expressed in conflicts between and within state agencies as proxies for public stakeholder interests. In 2008, former Governor John Huntsman formed the Great Salt Lake Advisory Council to study issues relating to the lake. The Council made recommendations for preserving the level of the lake (Great Salt Lake Advisory Council, 2012 and 2017). State wildlife managers conducted studies of bird populations dependent on the Great Salt Lake marshes and started to form a Great Salt Lake bird conservation strategy (Don 2002 and 2012). The Utah Department of Natural Resources developed a lake management plan, but the plan, which contains a detailed, well-thought out assessment, generally only specifies that further studies will be conducted if the lake falls below specified future set points (Utah Department of Natural Resources 2015). As these events that favored preserving the lake for bird wildlife unfolded, the Utah Board of Water Resources moved forward with its plans to spend 2 billion to develop and withdraw 220,000 acre-feet of water from the Bear River that flows into the Great Salt Lake. In February 2016, Wurtsbaugh and colleagues issued their white paper warning that the area of the Great Salt Lake would decline by another 3 percent, or 30 square miles, and co-authors of the white paper included staff of the Utah Division of Water Resources, an agency supervised by the Utah Water Resources Board, and the Utah Division of Wildlife Resources. Utah Governor Gary Herbert formed a State Water Strategy Advisory Team that developed draft recommendations in September 2016 (Utah Water Strategy Advisory Team and Envision Utah, 2016). In January 2017, the Water Resources Board tabled its proposal to develop and withdraw water from the Bear River Basin after the private Utah Rivers Council demonstrated that the same amount of water could be developed from conservation at a much lower cost (Roth, January 23, 2017).

Much like the ongoing controversy between Salt Lake City and development interests over the Salt Lake valley watershed canyons (April 28th), the issue of whether the Great Salt Lake will remain as a viable stopping point for migratory birds traveling the eastern arm of the Pacific Flyway is one that will be revisited and re-fought periodically. The result may change in future, and then neotropical migrating birds seen in the canyon might decline dramatically and unexpectedly.

* * * *

On May 27th, 2012, the City has installed many speed limit and travel warning signs in City Creek Canyon to enforce an even-auto and odd-bicycle day policy (Salt Lake Tribune). One resident describes the number of regulatory signs as “overkill”, and another notes that the signs advising walkers to keep on the stream side of the road as “ineffectual” (id). (In 2017, infrequent walkers in the canyon, including many families pushing baby strollers, regularly ignore or are unaware of the policy of walkers keeping to the up-canyon right, or streamside of the road, and automobiles and bikers should keep the up-canyon left side of the road.) On May 27th, 1888, the Salt Lake Herald proposed that in addition to a proposed road up City Creek Canyon, that a boulevard be created from the Capitol to the creek and then along to 11th Avenue.

May 26th (Revised)

Filed under: People — canopus56 @ 9:08 pm

Will the Great Salt Lake Disappear? – Part I

11:00 p.m. I am bedridden and despite repeated attempts, I am unable to rise for my daily canyon jog. It is a rest day. I fall in and out of sleep and awaken late in the evening, my head unable to focus from dreams of running in the Sun and of the sound of moving water. It is the start of a long federal holiday weekend. In six days, the canyon will reopen to public automobile traffic on alternate days, and the canyon’s solitude will lessen. I am conflicted by the coming change. For the two previous years, I was able to run to milepost 4.0 at at least every other day. My abilities have declined, and now I run either to milepost 2.0 or milepost 1.0. The opening of the road will allow me to fit runs in the upper canyon back into my schedule, but bringing an automobile in the canyon runs counter to my love this place.

* * * *

Whether or not northern Utah bird populations continue to be sustained depends on the continued viability of Great Salt Lake, and continuance of the lake now depends on the human will to preserve it. The lake sits on a eastern branch of the Pacific Flyway, and as such the lake is recognized as a migratory resource of international significance. Study of the bird ecology of the lake has focused on migratory water fowl and shorebirds, and estimates of shorebirds using the lake are about 3.2 million (Don 2002 at 6) and of migrating waterfowl about 5 million (Utah Department of Natural Resources 2013 at p. 2-109). Of migrating waterfowl, about 750,000 breed in the marshes along its shores (id). It is one of a series of inland lakes upon which migratory birds in the flyway’s eastern branch depend upon. The lake’s ability to sustain these numbers comes primarily from the March through July explosion of brine shrimp and brine flies. Densities of brine shrimp can reach 3,000 per cubic meter of water in June and brine fly larvae reach about 40 per cubic meter of water in August (Don 2010, pp. 24-25). Given that there are about 570 square kilometers or 570 million square meters (141,000 acres) of seasonal and permanent wetlands (Don 7-12), the top meter of lake during the peak summer season may contain 1.7 trillion brine shrimp and 22.8 billion fly larvae.

It is a reasonable supposition that the future population of birds in the canyon also depends on the health of the lake’s eastern marshes. Most research on the lake’s bird ecology has focused on shorebirds and waterfowl, and it is less clear on how other neotropical birds such as those found in the canyon utilize the lake during their migrations. Do they canyon hop up the western slope of the Rocky Mountain’s spine in central Utah or do they, like waterfowl, fly between inland lakes along Utah’s western and central deserts? The Cornell Laboratory Ebird checklist of the closest marsh to the canyon, the eight mile distant Farmington Bay Waterfowl Management Area, shows 254 species and this includes almost all of the birds seen in the nearby canyon.

The forty by sixty mile Great Salt Lake is showing signs of disappearing as northern Utah’s population, which is projected to double by 2050, due to excessive upstream water withdrawals. At first impression, that this large inland sea of about 1,700 square miles with no outlet to the ocean might evaporate within thirty years seems an outrageous proposition, but there is ample precedent. A similar shallow inland sea about fifteen times the size of the Great Salt Lake, the 26,000 square mile Aral Sea in Kazakhstan, reduced to 10 percent of its original area from 1960 through 2007. The Aral lake’s demise was by design: Soviet era planners diverted most of its inflow to support agriculture and they knew the lake would disappear. A similar fate fell upon California’s Tulare Lake. Utah’s Great Salt Lake is currently the largest lake in the United States outside of the northeast’s Great Lakes, but this was not always the case. The Tulare Lake was a freshwater endroheic playa lake: a shallow lake with no outlet to the sea that has large dry pan areas. It had a maximum area in 1879 of about 1,800 square miles. Historically, Tulare Lake supported a pre-Euro-American population of 70,000 First Peoples. Withdraw of its source waters to support agriculture in California’s central valley, that grows one-third of the nation’s fruit and vegetable produce, resulted in the complete evaporation of the lake. While the Aral Sea is and California’s Tulare Lake was larger than the Great Salt Lake, the 188 square mile Sevier Lake in central Utah is smaller, and like the Great Salt Lake, it is an endroheic playa lake. The Sevier Lake, that had a maximum historic depth of 15 feet, naturally evaporated in the nineteenth century, but after Utah’s peak flooding of 1985 to 1987, the lake refilled to its historic high. Since then, agriculture withdrawals have again almost entirely evaporated the lake.

Utah’s population has reached levels such that about 40 percent of water in rivers that feed the Great Salt Lake have been withdrawn for human use or reserved for wildlife protection, and their use, along with an extended drought, has reduced the lake’s level by 11 feet, its volume by one-half and its area by about one-half since the arrival of the Euro-American colonists in 1847 (Wurtsbaugh et al 2016). The lake’s surface area declined from about 1,600 square miles to 1,050 square miles in 2015, and this exposed 550 square miles of new dry lake bottom. In 2016, the lake reached a new historic low level, resulting in much of the southeastern lake bed, next to Farmington Bay and the canyon, turning into a dry pan.

Another sign of high upstream water withdrawals is Utah Lake, that is about thirty miles south of the Great Salt Lake and which drains into the Great Salt Lake to the north via the Jordan River. In recent drought years, the level of Utah Lake has also declined, and one consequence is that from 2014 through 2016, the lake now experiences an annual July toxic algae blooms containing sufficient levels of toxins to be hazardous to human health that require closing parts of the lake to boating and its shores to swimming (Salt Lake Tribune, July 15, 2016; Utah Department of Environmental Quality 2017b). The toxic Utah Lake algae flush from Utah Lake, down the Jordan River through the populated center of Salt Lake Valley, and out in to the Great Salt Lake (Utah Department of Environmental Quality 2017, Maps of toxic level sites). The shallow Great Salt Lake naturally contains high, but not toxic levels, of green and red algae, and due to the 1959 construction of an earthen railroad causeway across the northern third of the lake, differences in the two populations of algae can be seen from low earth orbit (NASA 2017)

Researchers’ ability to model the level of the Great Salt Lake has improved and significantly changed in the last ten years with the addition of historical tree ring studies. In 1997, Wold and colleagues built an early dynamic model of the hydrology of the Great Salt Lake and its salt content in its northern and southern arms that are divided by the causeway. In response to climate change concerns in 2012, Mohammod and Tarboton and in 2015, Gillies and colleagues prepared updated models using improved climate records based on an expanded climate record from 576 years of tree ring measurements. In 2015, Shope and Angeroth expanded Wold’s model of salt loading. Finally, in 2016, Huybers, Rupper and Roe worked on a dynamical model of the delayed response time of the Great Salt Lake’s lake level to prior year’s precipitation.

In a 2016 white paper, Wurtsbaugh et al of Utah State University raised the concern that if further water withdrawals are taken from the lake’s upstream water sources, such as another 250,000 acre feet from the proposed Bear River Project, then the lake will decline between another 8.5 and 14 inches and will expose and dry out between another 30 to 45 square miles (Wurtsbaugh et al 2016; Utah Division of Water Resources 2004). (1.2 million acre feet is currently reserved to flow to the Bear River Migratory Refugee, but in recent drought years, less than that amount has reached those marshes.) Although Wurtsbaugh and colleagues did not discuss the impact the proposed withdrawal would have on Great Salt Lake migratory bird populations, they noted that declining lake levels currently impact human health in the form of increased dust particles.

The dust particles referred to by Wurtsbaugh and colleagues come from dust storms. The ancient Lake Bonneville, including the dry Sevier Lake bed and the expanded dry pans of the newly exposed Great Salt Lake bottom generate large dust storms, called haboobs in Arabian desert, that floods the Salt Lake valley and the canyon with fine particles. These storms aggravate urban asthma. (One such wind storm most recently occurred on May 24th and it covered my car in a thick light brown layer.) The largest man-made source of dust in the United States is the Owens Valley lake bed – an artificially created dry lake in central California generated by Los Angeles withdrawing water from the lake to supply Los Angeles municipal drinking water. Los Angeles has spent 1.2 billion USD on dust suppression in Owens Valley (Iovenko 2015).

Another human health risk of a drying lake that has yet to be analyzed by governmental or academic research is lake purification. Salt Lake City residents are familiar with summer lake stench. One or two times during each summer, clouds of stench from organic matter dying in the lake invade the city. In Utah, these are a minor aesthetic inconvenience, but California’s evaporating 340 square mile Salton Sea provides precedent for larger impacts. The 45 foot deep Salton Sea was created in 1905 by an engineering accident that diverted the Colorado River into an ancient dry lake bed. In 2015, the Coachella valley surrounding the Salton Sea had at least five air quality alerts from rotting-egg smell emanating from the sea (Iovenko 2015).

An unknown risk in the Huybers et al’s model of the Great Salt Lake water levels is the potential for dynamic chaotic responses. Huybers and colleagues used ordinary differential equations for their model. Mathematicians and physical sciences well now that such equations contain chaotic boundaries in which the system responds in new and unlikely directions once certain break points are reached. However, the state-of-the-art expert opinion, summarized in Wurtsbaugh et al, is that increases in the decline of Great Salt Lake levels will be incremental and not chaotic. The lake, and its life-giving marshes that support northern Utah bird life in the canyon, should continue for the near future. Notwithstanding present model studies, that the Great Salt Lake might disappear completely in the next thirty years is still be within the scope of probable scenarios.

* * * *

On May 26, 1983, City officials proclaimed a flood emergency in Salt Lake City after a winter of heavy snowfall followed by a late warming (Salt Lake Tribune). In a April 29, 2011 retrospective article, Salt Lake Councilperson Grant Mabey recalled how he had witnessed the 1952 flooding of downtown by City Creek Canyon, and in 1983 he feared a repeat of that event (Salt Lake Tribune). The city pre-ordered 250,000 sandbags (id). Sandbagging State Street kept City Creek from flooding underground parking at ZCMI Mall (id). On May 28th, Mayor Ted Wilson learned that rock and tree debris from City Creek Canyon were clogging up the 1910 underground culvert down State Street and a second pipe system along North Temple (id). The flood waters receded by June 11, 1983. On May 26th, 2003, the Salt Lake Tribune reviews the history of the establishment of Memory Grove Park (Salt Lake Tribune).

On May 26th, 1933, a letter to the Salt Lake Telegram editor stated that City Creek Canyon Road had deteriorated into a “deplorable condition.” On May 26th, 1906, the Commercial Club inspected construction work on road improvements up City Creek Canyon Road to 11th Avenue (Salt Lake Tribune).

May 25th

Filed under: Raptor, Unidentified — canopus56 @ 9:05 pm

Raptor Attack

2:30 p.m. Walking along the wall of green tree leaves near mile 0.2, there is flash of gray, a commotion in branches, and a flurry of falling leaves. I turn quickly to see the back of a grey raptor with molted yellow legs sticking out of a tree. It floats back, swivels up canyon with any small bird in its claws, and flys up canyon low above the road. It will happens in a one or two seconds and I am unable to see the bird’s face in order to clearly distinguish whether it is a Peregrine falcon or a Cooper’s hawk. Later, I turn around and catch a glimpse of the top back of mallard rounding the next bend and flying a foot or two above the surface of the road.

* * * *

On May 25th, 1922, the Salt Lake Telegram reports that prisoner chain gangs are working on City Creek Canyon Road. On May 25th, 1908, three people where arrested for speeding in City Creek Canyon with their horse carriage while under the influence alcohol (Intermountain Republican). On May 25th, 1903, heavy flooding and a landslide collapsed spring tunnel no. 1 about two miles up City Creek Canyon (Deseret Evening News). On May 25th, 1895, the City prohibited two units of the National Guard from conducting exercises in City Creek Canyon out of water protection concerns (Salt Lake Telegram). On May 25th, 1886, the Salt Lake Herald reported that City Creek Canyon had been crossed by snowslides in about 12 places, including one 30 foot deep slide.

May 24th

Birds of Concern

5:00 p.m. At dawn today, from the west half of the valley, I could see the upper slopes of Grandview Peak that feeds the stream, and they are still covered at some depth. Significantly, overnight temperatures have returned the sixites. This early evening, a summer storm front moves through from the southwest bringing warm rain and micrcobursts of fifty mile an hour winds. Under their pressure, individual trees in the canyon wave back and forth violently under momentarily black skies. The first Woods rosa blooms have opened for the season, and in the lower canyon, some Gambel’s oak leaves have reached a mature length of 5 inches. Since it is early in the evening, most birds are quiet. At Guardhouse Gate, five Warbling vireos weakly call and at picnic site 5, another is joined by a Song sparrow.

Near mile 0.6, I stop along the road to tie a shoelace. Looking up, a male mallard is swimming on the stream’s surface about seven feet below the roadside. The mallard is grazing on streamers of underwater grass that waves under the swiftly moving current.

Stink bugs line the roadside today, all uniformly standing with their abdomens pointed upward at above the centerline of the road. Given the presence of the spring birds, this is a wise resting posture. A two-inch unidentified, hair covered caterpillar crawls along the road. In a possible example of mimicry, each of its segments has a white, black and brown pattern that is nearly identical to the Variegated Meadowhawk dragonfly. Further up canyon, a one-inch beetle has two bright perpendicular orange bars on its back, and the orange tone is the same found on a Lady Bug. It is a carrion eater – the Burying beetle (Nicrophorus tomentosus). Unlike other Nicrophorus species, this beetle does not bury its carrion, but only drags it to a shallow depression and covers the carcass with leaf litter. A colony of tiny brown ants erupts from a crack in the pavement. A four inch circle contains an estimated 500 individuals that all crawl on top and over each other. About eight unidentified small brown butterflies are seen along the first mile. Their wings have a bright light-brown metallic upper side.

* * * *

Under the United States dual-sovereignty scheme, protection of endangered and other birds is divided between federal and state authorities. The federal government through the U.S. Fish and Wildlife Service has primary authority to protect both endangered and threatened bird species through the Endangered Species Act of 1973 (16 U.S.C. Sec. 1531), and with respect to non-endangered migratory birds, such as those seen in the canyon, through the Migratory Bird Treaty Act of 1918 (16 U.S.C. Secs. 703-712). The federal government is authorized to enter into cooperative agreements with States to share protective efforts for the migratory songbirds seen in the canyon through the Neotropical Migratory Bird Conservation Act of 2000 (16. U.S.C. Secs. 6101-6109). While no federally endangered species are currently known to frequent the canyon, historically, the Yellow-billed cuckoo, a federally listed threatened species, may have used the canyon (Rawley).

The State of Utah, under its sovereign authority, also designates sensitive species that are given special monitoring attention (Utah Code Ann. Sec. 23-14-1 et seq.; Utah Administrative Rule 657-48; Utah Department of Natural Resources 2015), and the State exercises that authority under a policy to “seek to balance the habitat requirements of wildlife with the social and economic activities of man” (Utah Code Ann. 23-14-3(2)(iii) (2017)). Federal threatened species and Utah state sensitive species share the common quality that a birds’ declining populations raise issues as to its continued viability. State sensitive species found in the canyon are Bald eagles and Northern Goshawks. Other State sensitive species historically, but not currently, found in the canyon include Bobolinks (Dolichonyx oryzivorus) and Ferruginous hawks (Buteo regalis) (Utah Department of Natural Resources 2015). In designating a sensitive bird species, the state circumscribes its authority to those species for which “there is credible scientific evidence to substantiate a viable threat to continued population viability” (Utah Administrative Rule 657-48; Utah Department of Natural Resources 2015). The state relies principally on the Breeding Bird survey data (May 21st, May 22nd and May 23rd) (Utah Department of Natural Resources 2015, Appendices; Sauer et al 2017).

Bird designation on the state list occurs primarily either because of global population size combined with local population trends. The State designates the Bald Eagle as a sensitive species primarily because of the size of the eagle’s continental breeding population. In 2006, there were about 10,000 breeding pairs of bald eagles left in the United States (out of a population of 70,000), and the 10 bald eagles that over-winter in Utah represent about thirty percent of all Bald Eagles west of the Rocky Mountains (Utah Department of Natural Resources 2015, Appendix A, Sec. 5.1). In using the Partner’s-in-Flight rating system, the eagle would be given a population concern index of 5 for having less than 10,000 breeding pairs. Conversely, the Bobolink have about 10,000,000 global breeding pairs, but the decline in the global and local populations is 1.6 percent per year (id, Appendix A, Sec. 5.8). The Ferruginous hawk (id, Appendix A), like the Peregrine falcon, is a recovering raptor with an estimated global breeding population of 80,000, or a population concern index of 4. But, due to recovery management efforts, its population is increasing. That both the Bobolink and Ferruginous hawk are believed to have been widely present in Utah historically, but now are largely absent from the state also supports their Utah sensitive species status (id, Appendix A).

In contrast, other birds that receive a private Conservation Concern Index of 13 like the Virginia’s Warbler and the Plumbeous vireo and that are found in the canyon are not designated by the State. Although they have locally declining population trends, the Virginia’s Warbler has a global breeding population of about 400,000 pairs and although the Breeding Bird Survey found only 192 pairs of Plumbeous vireos in the Intermountain West (Sauer et al 2017), the Plumbeous vireo has a global population of about 2,700,000. The Peregrine falcon is another bird not designated on the state’s list (Utah Department of Natural Resources 2015). The Peregrine was delisted by the federal U.S. Environmental Protection Agency in 1999, and the global breeding population of Peregrines is about 93,300. But there only about 90 breeding pairs of this still recovering raptor, or a sufficiently small population that it could wiped out by a set of determined illegal hunters in a few weeks. Although I feel some of these Utah state sensitive bird specie designations to be inconsistent, e.g. – the Boblink but not the Plumbeous vireo is designated, they evidence a process in place, albeit an imperfect process that operates under considerable uncertainty, to monitor and assess potential crashes in bird populations.

Uncertainty in the state-of-knowledge about bird populations and in the process of designating them for more intensive monitoring is also unsettling. Conversely, the signs that these researchers and their models provide allow us to act more thoughtfully than simply relying on political beliefs and folk-tales about nature’s ability to cope with change. That a considerable multi-state monitoring effort coupled with recovery planning exists is cause for celebration and not cynicism. That process has led to the ongoing recoveries of Peregrine falcons and Ferrigunous hawks. But even with all this effort, I find it hard to let go of the sense that we are pulling at the strings of nature’s web, and like Plato’s prisoners in his allegorical cave described in the Republic, our scientific efforts and mathematical models of specie risk give only a limited indirect view of a truer complexity that we do not understand.

* * * *

On May 24, 2007, 200 persons attend the annual Memory Grove clean-up (Salt Lake Tribune). On May 24th, 1996, veterans groups plan to gather at Memory Grove for Memorial Day. On May 24th, 1920, the North Bench Improvement Association Chairman G. A. Iverson published an artist conceptual drawing for a park in lower City Creek including a viaduct across the canyon at 5th Avenue (Salt Lake Telegram). On May 24th, 1913, members of the Rotary Club and City Commissioner Korn plan to tour the proposed route of a scenic highway up City Creek Canyon and into Morgan County (Salt Lake Tribune). May 24th, 1907, the Salt Lake Tribune urged the creation of reservoir dams in City Creek and Parley’s Canyons. On May 24, 1903, the Salt Lake Tribune overviewed many canyon drives around Salt Lake City, including in City Creek Canyon. One photograph includes Shippler’s image of a carriage going up a heavily wooded City Creek track (id). The article also relates a parable and legend about a young man who located a lost gold mine, and contrary to his Mormon bishop’s advice, spent his life in a vain attempt to relocate it. His futile search was described as his “punishment for his disobedience to the mandate of the prophet revealed by God” (id). The Tribune noted that hundreds of City residents go into the canyon on the weekends.

May 25, 2017

May 23rd

Continental Scale Bird Population Trends – Part II

3 p.m. Unwittingly, I disrupt the community of birds just north of Guardhouse Gate. It is another warm, clear day, and I plan to spend this afternoon’s run developing my novice song bid, soundscape skills (May 6th). Over the weekend, I have assembled recordings of about forty-five birds from the Cornell Laboratory observing lists (May 20th), and they have been transferred to my telephone. The songs are sorted in order of similarity. Thus, I hope to learn the songs by listening to them throughout my day and by replaying the recording to identify unseen birds from their sounds alone. But this is not an easy skill to acquire. Some birds caw, others have warbling songs, and still others have four or five beat calls. The variations are endless: some warbling songs end on a high note, others on a low, some are long, others are longer. Call-like songs begin on a low-note, followed by a three or six beat high tone; others begin on a high-note, followed by a five count low-note. Others have a rapid trill. Nor is there much organization by either genus of bird or its outward appearance. The Black-headed grosbeak has song similar to the smaller Song sparrow, but the Rufous-sided towhee, which looks very similar to Black-headed grosbeak, has a two-beat call followed by a rapid, machine gun trill. The Lazuli bunting, which has a seed-crushing mouth sounds like the grosbreak and towhee, has a song that is a deeper throated version of the smaller Warbling vireo which has a mouth shaped for catching insects. Conversely, similarity of form can imply similarity of call. Some of the most colorful songbirds in the canyon are insectivores. The Warbling vireo, the Yellow warbler, and the Virginia’s warbler are similar in form and have variations on the same song, like some avian version of humanity’s proto-Indo-European language, but they do not all share the same family in the binomial nomenclature system. The Song Sparrow and House Sparrow are similar in form and voice tone, but their songs are very dissimilar.

Song birds along the first mile can be roughly divided into four communities: there is cluster between the Gate and mile 0.1 and picnic site 1 along both sides of the stream. A second group collects around the bend above picnic site 3 on the east side of the stream. A third is in a hollow below picnic site 5 on the west side, and a fourth along the western oak-covered slope near mile 1.0. These cluster at every 0.2-0.3 miles are connected by loose strings of individual avians. To these four neighborhoods, a five lays to the west of and along the Pipeline trail where the Gambel oak forest gives way to open grass and brush lands. The predators – Peregrine falcons, Red-tailed hawks, Cooper’s hawks, and American kestrels (Falco sparverius) – form their own neighborhood hovering in the sky over the song birds.

I begin at the first group near mile 0.1, where yesterday there was a riot activity. Since today, it is later in the afternoon, things are more subdued, but I can still distinguish six or seven different, unseen bird voices. Initially, I struggle with making any identification, and I become absorbed in loudly replaying about ten songs that represent the voices at mile 0.1. I listen to one song, and then try playing the two or three best candidate recordings to select the best match. After five minutes, I look up, and three birds have come out of the nearby screen of green. A Lazuli bunting perches on the top branch of a thirty foot Box Elder tree. On a nearby Gambel’s oak, a female House finch perches and stares. Across the road in the Box Elder, there is a bright flash of red and yellow midway down the tree. It is a male Western tanager in full breeding plumage, and I start replay a recording of his species in order to keep his attention. For the two months of its breeding season, the head of the tanager turns a brilliant red, and this contrasts with its vivid yellow underplumage and black back. This male has caught the lengthening rays of afternoon sunlight that is softened by moisture in the air, and its red iridescent plumes blaze.

After working with the recordings for one-half hour, I am able to make rudimentary identifications by sound alone of the the Western tanager, a Lazuli bunting, a Warbling vireo, a Song sparrow, and American robin. What strikes me about this lower community is its heterogeneity. There are perhaps seven species all sharing the same one-quarter square mile. They cooperate in sharing the space. Birds are known to share the same forest space by specializing in different food niches, it is early in season and food may be plentiful, and territorial nest building may not have been completed.

Traveling up canyon, the bird community in the hollow near picnic site 5 is populated by only Warbling vireos. Further up canyon, a lone Spotted towhee caws and trills. American robins are dispersed along the first mile road.

Spring Azure butterflies have had a mini-R reproductive explosion. Usually there are three or four larger adults along the first mile road. Today, I count 20 smaller streaked blue versions only three-quarters of an inch in size. The next generation has hatched, and they play among newly cut grass. The City has come through the canyon, and as a fire prevention measure, it has mowed down the two and three foot grass around each picnic area. The air is sweet with cut-grass smell, and further back from the sickle’s cut, the green grass is interrupted by the first loud yellow of newly opened Toad flax (Linaria vulgaris), also called Butter and Eggs plant. This common roadside noxious weed has a beautiful, intensely yellow and orange, orchard like bloom.

Coming back down canyon close to six in the evening, these bird communities are silent, and only the evening town criers of the canyon, the House finches, repeat their their one-high, two low, call of three notes. Near mile 0.5, an immature Terrestrial gartersnake (Thamnophis elegans) crawls across the road. The garter eats insects, e.g. – the Stink bugs that rest along the roadside and snails (May 16th).

Incongruous to this serenity, a group of ten people walk up the road, and two have small caliber handguns strapped to their sides. These “open carry” gun rights advocates, whose right to openly carry guns is sanctioned by the state legislature, have no need for these weapons. Discharging them in the canyon below mile 0.4 violates city and county ordinances, and regardless of the legality, their attempt to drag society back into uncivility and barbarism of some imagined historical western landscape is uniformly disapproved of by the majority of members of the surrounding neighborhoods. Regularly, such displays or the discharge of firearms results in canyon walkers making worried telephone calls to the police, and the police do respond to hand out tickets. While I have some appreciation of how individualism and capitalism can drive people into a mindset that perpetually fears others, this group is not in any danger in the canyon this evening. No one is hiding in the bushes ready to rob them, and their flashy presence in the canyon is an unwelcome intrusion. Like the songbirds around them and the red blaze of the tanager, their weapons are an overstated claim for social attention and of personal territory.

* * * *

The National Audubon Society recently has become a leader in continental scale studies of populations and of future threat forecasting. In 2013, the National Audubon Society released their report titled “Developing a Management Model of the Effects of Future Climate Change on Species: A Tool for the Landscape Conservation Cooperatives” based on its Christmas Bird Count (discussed below) and BBS data (National Audubon Society, Schuetz, Distler, Langham, 2013). Coupled with global climate models, the Audubon’s Christmas Bird Count data allowed the Society to model changes in bird summer and winter ranges, summarized in national maps, based on varying degrees of global warming. In the Great Basin (and in the canyon), their model predicted increases in bird species richness during the winter season and declines in bird species richness during the summer season (id, 27-29, Figs. 2.8-2.9). In an updated study, Langham and colleagues from the Society used further advanced modelling techniques with respect to 588 North American continental birds, and they forecasted that by 2080 under a high-emissions high-warming scenario, about 53 percent of the 588 species would find that 50 percent of their current range, particularly for summer breeding, would become unsuitable (Langham et al. 2016).

With respect to continental-scale population trend studies, the Audubon Society’s annual Christmas Bird Count has collected bird counts since 1901. Unlike professional studies, the Christmas Bird Count (CBC) suffers from a number of inherent design controls. CBC bird identifications are made by error prone amateurs at differing locations and differing types of locations, e.g. – in the field or at feeders, between each annual sampling. Fluctations in the number of observers between years can introduce observation bias. Those characteristics limit the ability to use CBC data to predict trends in bird populations using traditional statistical techniques. Conversely, the CBC has been the collecting massive amounts of data from numerous amateurs around the country for more than a century. For example, in the 2016 count, over 56 million birds were manually counted. Increases in inexpensive computing power and application of advanced statistical techniques eventually allowed for the use of this citizen science data to make reasonably statistically confident statements of about trends in bird populations sampled from a wide variety of habitats. In particular, the mathematical techniques of multi-level regression, also called hierarchical modelling, allows for the extraction of bird density trends over time from the massive, but uncontrolled, data sources collected by the Audubon Society. Since 1990, habitat change from climate warming has become an important issue. Application of these analytic improvements also allow trends to be examined in the context of varying habitats, and thus, making the CBC data useful for exploring trends in habitat change from development and climate warming affects bird populations.

Soykan and colleagues with the National Audubon Society estimated North American continental populations of 551 North American bird species and for a subset of 228 species that do not frequent bird feeders using the Society’s annual Christmas Bird Count data (Soykan et al. 2016). They found that for all 551 species, 68 percent had increasing density trends from 1966 through 2013. Thus, 32 percent have a declining trend, a fact exploited in NACBI glosssy annual “State of Birds” reports. For the subset of 228 species, Soykan et al found an 0.9 percent growth trend across 1966 to 2013. They noted the geographically, declining species were concentrated at lower latitudes and increasing species were located at higher latitudes (id), and this suggests that generally, bird populations are shifting their ranges northward. For the future canyon, this is consistent with Schuetz, Distler and Langham’s 2013 modelling suggesting that warmer climates would increase winter species diversity in the Great Basin as birds move their ranges north (above).

Soykan et al’s supplemental data provides further insight into Utah trends (Soykan et al. 2016), but it also underscores the problems and differences of professional verses amateur data collection. Conflicting with the Parrish, Norvell and Howe declining Utah trends for 1992 to 2005, Sokyan and colleagues found from CBC counts for 1966 to 2013, an increasing bird population trend of 2.7 percent for Utah (Table S.4) and 2.8 percent for the Great Basin region (Table S6). Students of introductory statistics will recall the Rule of 70: the doubling time or halving time of a population can be estimated by dividing 70 by the annual rate. Thus, the CBC trend suggests that Utah bird populations will double in 25 years, while the Parrish, Norvell and Howe rate suggests populations would halve in 70 years.

Although overall, Soykan et al’s continental population trends derived from CBC counts were statistically similar to 228 professional BBS specie trends, for a small subset of 33 species, CBC and BBS trends significantly differed (Table S.9). Some of the differences involve species frequently seen in the spring canyon. For two species, Swainson’s Hawk and the Black-headed Grosbeak, the CBC found continental declines around 3 percent per year, while the BBS surveys found increases of less than 1 percent per year. A three percent decline suggests populations will halve in about 25 years. For eight other species found in the canyon, the CBC found a slight increasing population trend, while BBS found populations declining at more than 1 percent per year: Song Sparrow, American Kestrel, Belted Kingfisher, Mourning Dove, Orange-crowned Warbler, Yellow Warbler, Chipping Sparrow, and the Broad-tailed Hummingbird.

Again, overall bird population studies continue to indicate that currently and for the near future, bird specie diversity and bird populations should remain stable or have a slight decline, as indicated by the Parrish, Norvell and Howe studies (Parrish et al. 2007). Soykan et al and Langham et al conclude overall birds are moving their summer ranges northward and they are decreasing the area of the summer and winter ranges around the best habitats in response to a warming climate, and under that scenario, Utah bird populations would increase as birds move further north. But whether population trends will decline in a severe global warming occurs scenario, whether they will increase as more birds move their ranges north in response to southern latitude warming, or whether Utah bird populations will increase after the reversal of the current Intermountain drought phase of the Pacific Quasi-Decadal Oscillation (February 7th) remains to be seen. Continued monitoring, such as that occurring through professional and citizen science surveys, is the only means to have a definitive early warning of any dramatic change, for better or worse. Other unanticipated changes, both good and bad, may also occur.

These mathematical models of bird populations, as with proof of biophilia studies, provide only the most general of signs and no clear answers. Proof to a reasonable degree of scientific certainty cannot be found in the statistics of bird populations, and thus, we are forced to fall back on human values and human judgment in deciding what to and how to protect nature. But as with local weather and the Pacific Quasi-Decadal Oscillation, it is only by looking on a continental scale that over-arching patterns in nature can be seen. A local-only perspective, like Plato’s prisoners in his allegorical cave, can give us a limited, uninformed, and wrong view of the world.

There is a further brilliance to the CBC data and Schuetz, Distler and Langham’s 2013 study. They provide detailed ranged summer and winter maps for 36 bird species of concern (id, 114-181) on a continental scale and with previously unseen fidelity (Schuetz, Distler and Langham’s 2013). Presumably, such maps can be generated for all birds in the CBC study. Previously, bird summer and winter range maps were rendered with broad colored areas across a U.S. map with northern and summer range lines, e.g. – those seen in my old 1990 Peterson’s Western Birds guide or my favored, dog-earred 1966 Guide to Field Identification of North American Birds, illustrated by Arthur Singer. The ranges of migration were indicated by broad directional lines. By combining CBC bird observations with satellite habitat data, Schuetz et al render detailed core range maps.

* * * *

On May 23rd, 2012, Lowell Bodily, Salt Lake Valley Health Department, again reported on homeless tent camps in the valley, and he notes that some homeless camp along the Bonneville Shoreline Trail in and near City Creek Canyon (Salt Lake Tribune). On May 23rd, 2006, the Lion House reports that it hosts about 82,000 visitors per year (Salt Lake Tribune). (In the 1850s, the Lion House sat next to the tollgate that controlled access to City Creek Can yon.) On May 23rd, 2002, in a letter to editors of the Salt Lake Tribune, a Sandy resident decries how a new luxury home has defaced the beauty of Ensign Peak and City Creek Canyon (Salt Lake Tribune). On May 23rd, 1996, Anschutz Ranch East Pipeline Inc. proposes to build a crude oil pipeline from Park City that would cross through City Creek near the water treatment plant (Salt Lake Tribune, June, 24, 1996). On May 23rd, 1914, the Salt Lake Telegram published a photograph layout and description of driving the new scenic boulevard up City Creek, along 11th Avenue and down 1300 East (Salt Lake Telegram). On May 23rd, 1905, Land and Water Commission Ben D. Luce requested that the City council to ban automobiles from driving up City Creek Canyon due to the possibility that they will cause accidents by frightening horses (Salt Lake Herald).

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 21st

Filed under: Birds, Leopard slug, Light, Sounds, Weather — canopus56 @ 4:40 am

Utah Bird Population Trends

8:30 p.m. I am on a short, quick jog near twilight, and towering broken clouds float from the west to east over the lower canyon. As the sun nearly sets, dimmed green and brown ridgeline contrasts with slate gray cloud bottoms below the descending sunset line, but the cloud tops are enveloped in a bright pink and white hues against the deepening blue sky. Two Leopard slugs take advantage of the cool evening to cross the road. Twilight turns to night. Unlike my snowbound fall night run (December 12th) which focused on the sound of silence, tonight the crashing white noise of the stream drowns out any thoughts as I return to the gate through the darkness.

* * * *

Bird populations are almost impossible to estimate with any accuracy. The best that can usually be done is to measure changes in the density of birds and from those changes a change in the overall population level can be inferred. Numerical population estimates exist for Utah game waterfowl birds and endangered species that travel along the eastern branch of the Pacific Flyway that passes through the Great Salt Lake. The Pacific Flyway is one of the three great North American migratory bird flyways that stretch from Canada to central Mexico. Thus, the populations of many birds see in the canyon that winter to the south is dependent on the availability of habitat two thousand miles to the south. Similarly, bird populations seen to the north and south of Utah are dependent on the marshes of the Great Salt Lake. There is no alternative route for birds to cross Utah and Nevada’s arid lands.

Olson of the U.S. Fish and Wildlife Service reports a 13 percent increase in waterfowl birds between 2009 and 2016 (55,868 divided by 49,464 birds) (Olsen 2017). (The Utah study methodology changed in 2009 and this prevents examining longer term trends back to 1992). With respect to non-game birds such as those smaller song birds in the canyon, Parrish, Norvell and Howe with the Utah Division of Natural Resources 1992 to 2005 study of 37 Utah bird sites found that (Parrish et al. 2007; Novell, Howe and Parrish 2005). Their study created the longest running dataset of high quality bird density estimates for the western United States (Parrish et al. 2007, 77). About half of Utah’s 440 bird species are residents; they other half are annual neotropical migrants; and, more than 70 percent of those birds use riparian habitats, like the Jordan River, as habitat during part of their life cycle (Parrish et al. 2007, 12). Based on estimated the density of 202 species of Utah birds from 1996 to 2005 from observations and recaptures, Parrish and his colleagues found that overall Utah bird populations have declined 5 percent over the thirteen years from 1992 to 2005 (id, 4, 67, Fig. 8). The Utah bird decline should be viewed within the context of the fifteen year drought cycle. The Great Salt Lake water level has been declining, its marshes have less water, and other bird refuges are drier. Population declines would be expected from such changes in habitat. Parrish, Norvell and Howe did not have a study site in City Creek Canyon.

The decline in Utah neotropical migratory birds is not uniform for birds found in City Creek Canyon. Between 1995 and 2001, the density of American Goldfinches, American Robins, Black-headed Grosbeaks, Broad-tailed hummingbirds declined, but the density of Yellow Warbler’s increased (Novell, Howe and Parrish 2005, 561-562, Figs. 2-3). Gross waterfowl populations along the Great Salt Lake are increasing, despite the drought. Available copies of their 2007 report do not provide density information disaggregated by individual species. In summary, Utah state neotropical bird studies indicate that the population of birds in the canyon relatively stable, but populations may decline further based on changes in local climate.

* * * *

Given that a high proportion of Utah birds that use riparian habitats, Parrish, Norvell and Howe recommended adoption of various management activities to improve habitat along Utah’s waterways without necessarily waiting for further study demonstrating the efficiency of remediation efforts in improving bird populations (Parrish et al. 2007, 76-77). Cause and effect are well known and obvious in these circumstances. In 2011, the Utah State Legislature authorized the expenditure of 37 million USD to support the Utah Watershed Restoration Initiative for joint private-public riparian rehabilitation ventures (Clark, A., and Utah Department of Natural Resources, 2013; (Utah Department of Natural Resources, 2017b). Through 2016, the Utah Division of Wild Resources reports that it has completed 1,607 projects covering 1.3 million acres of Utah Wetlands.

The Utah Watershed Restoration Initiative has funded Yellow starthistle abatement in City Creek Canyon during 2010 through the present (Utah Department of Natural Resources, 2010, 2016, 2017a, 2017b). Those projects included chemical spraying of 8 acres in Pleasant Valley to control the weed in 2017 (Project Id. 3693), 2016 (Project Id. 3404), 2013 (Project Id. 221), spraying 70 acres in 2011 in Pleasant Valley (Project Id. 1642), and spraying 150 acres five miles up the canyon in 2010 (Project Id. 1464). Another spraying in the canyon is proposed in 2018 (Project Id. 4040). The Initiative funds the Utah Conservation Corps currently working in City Creek (May 17th, October 16th) (Utah Department of Natural Resources, 2017a).

On May 21st, 2003, in a letter to the editors of the Salt Lake Tribune, Richard Pieros observes how new FAA landing flight paths for the Salt Lake International Airport over Emigration Canyon, City Creek Canyon and the Avenues has resulted in loss of solitude. (Later, the FAA revised the flight paths and airliners no longer take off or landing over City Creek Canyon or the Avenues, except in rare unusual instances. This transfers the airport noise burden to West Valley City residents and to wildlife along the shores of the Great Salt Lake.) In May 20th, 1994, Bryant Elementary School Children participated in a neighborhood cleanup of Memory Grove and City Creek Canyon (Salt Lake Tribune). On May 21st, 1916, City Engineer Sylvester Q. Cannon planned to measure the volume of lakes in City Creek Canyon in order to see if they were suitable to act as reservoirs (Salt Lake Tribune).

May 20, 2017

May 20th

Spring Bird List

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

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

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

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

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

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

* * * *

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

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

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

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

• Cooper’s Hawk (Accipiter cooperii).

• Golden Eagle (Aquila chrysaetos).

• Northern Goshawk (Accipiter gentilis).

• Peregrine Falcon (Falco peregrinus).

• Red-tailed Hawk (Buteo jamaicensis).

• Sharp-Shinned Hawk (Accipiter striatus).

Order Anatidae – Ducks

• Mallard (Anas platyrhynchos).

Order Apodiformes – Swifts and Hummingbirds

• Black-chinned Hummingbird (Archilocus alexandri).

Order Galliformes – Pheasants and Guineafowl

• California Quail (Callipepla californica).

• Chukar (Alectoris chukar).

• Wild Turkey (Meleagris gallopavo).

Orders Piciformes and Coraciiformes – Woodpeckers and Kingfishers

• Belted Kingfisher (Ceryle alcyon).

• Downy Woodpecker (Picoides pubescens).

• Northern Flicker (Colaptes auratus).

Order Strigiformes – Owls

• Western Screech-Owl (Otus kennicottii).*

Order Passeriformes – Larger Perching Birds

Family Corvidae – Crows, Jays and Magpies

• American Crow (Corvus brachyrhynchos).

• Black-billed Magpie (Pica pica)

• Common Raven (Corvus corax).

• Steller’s Jay (Cyanocitta stelleri).*

• Western Scrub-Jay (Aphelocoma californica).

Order Passeriformes – Mid-sized and Smaller Perching Birds

Family Cardinalidae – Cardinals and Grosbeaks

• Black-headed Grosbeak (Pheucticus melanocephalus).

• Lazuli Bunting (Passerina amoena).

• Western Tanager (Piranga ludoviciana).

Family Columbidae – Pigeons and Doves

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

• Mourning Dove (Zenaida macroura).

Family Emberizidae – Sparrows and Buntings

• Chipping Sparrow (Spizella passerina).

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

• Green-tailed Towhee (Pipilo chlorurus).

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

• Rufous-sided Towhee (Pipilo erythrophthalmus).

• Song Sparrow (Melospiza melodia).

• Spotted Towhee (Pipilo maculatus).

Family Fringillidae – Finches

• House Finch (Carpodacus mexicanus).

• Lesser Goldfinch (Carduelis psaltria).

Family Hirundinidae – Swallows

• Bank Swallow (Riparia riparia).

• Cliff Swallow (Petrochelidon pyrrhonota).

• Northern Rough-winged Swallow (Stelgidopteryx serripennis).

• Violet-green Swallow (Tachycineta thalassina).

Family Paridae – Chickadees

• Black-capped Chickadee (Poecile atricapillus).

• Mountain Chickadee (Poecile gambeli).

Family Parulidae – Wood-Warblers

• Orange-crowned Warbler (Oreothylpis celata).

• Virginia’s Warbler (Oreothylpis virginiae).

• Yellow Warbler (Dendroica petechia).

Family Turdidae – Thrushes

• American Robin (Turdus migratorius).

• Townsend’s Solitaire (Myadestes townsendi).

Family Tyrannidae – Tyrant Flycatchers

• Dusky Flycatcher (Empidonax oberholseri).

• Olive-sided Flycatcher (Contopus cooperi).

Family Vireonidae – Vireos

• Plumbeous Vireo (Vireo plumbeus).

• Warbling Vireo (Vireo gilvus).

Family – Other with Family Name

• Blue-gray Gnatcatcher (Polioptilidae Polioptila caerulea).

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

• Red-breasted Nuthatch (Sittidae Sitta canadensis).

• Ruby-crowned Kinglet (Regulidae Regulus calendula).

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

* * * *

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

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

* * * *

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

May 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).

* * * *

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.

* * * *

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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