City Creek Nature Notes – Salt Lake City

July 18, 2017

July 17th

Seed Dispersal, Porcupine and First Trout

2:00 p.m. Although the canyon is still in the estival and not the serotinal season, I have inadvertently stepped into a patch of common Foxtail barley (Hordeum jubatum L.), and my shoes are covered its spikelets. I pause to remove about twenty out. The serotinal season, which begins on August 15th, is the time of maximum seed production and dispersal. Although a native plant, Foxtail and like the invasive Cheat grass disperse by animals. Dispersal by animals is particularly effective, which explains why many invasive and weeds move their seeds by spikes and velcro-like surfaces that grab onto mammal fur and bird feathers. Others use animals. Along the road today around the cultivar crabapple trees (genus Malus) in the first mile, there are half-eaten rotting fruits. Birds have been pecking at them and consuming both the sweet pulp and seeds. Mule deer have already consumed the fruit on the lower branches. I have often wondered at the inefficiency of other plants like Gambel’s oak and Box Elder trees. Both produce large prodigious amounts of seeds at a great expense of energy, but only an infinitesimal portion of the seeds can ever be reasonably expected to reach maturity. The oak drops its seeds vertically by gravity, where they cannot do not sprout in the shade. Presumably the oaks are helped by Rock squirrels (Spermophilus variegatus) that move and store the acorns in their burrows. The Box Elder is covered in is catkins of helicopter seeds that by its aerodynamics float a short distance from its parent. Cottonwoods, Western salisfy (Giant dandelion), and Fireweed, respectively, produce pollens and seeds that parachute away from their parent suspended below a feathery pappus. Watercress (Nasturtium officinale) fruits and floats down the stream to establish new colonies. How watercress moves upstream is unclear. Perhaps small crushed leaves fall off the lips of deer that browse on it. Dandelions, who favor the stream’s banks, moves its seeds upstream on the wind and downstream by floating on the water. Other plants like the Gambel’s oaks and aspen trees increase their range asexually by extending tubers underground.

6:00 p.m. The heat of the Sun bakes the water out of the land, and afternoon thunder clouds, born from the Great Salt Lake and reservoirs covers the valley. The great cloud tops are only threats, and pass with leaving any life-giving water to the city or to the canyon. It has been several weeks since I last remember any rain falling in the canyon. Checking weather records, the last rainfall above a trace amount was about one-tenth of an inch on June 13th.

8:45 p.m. I take a second late-evening run thorough the cool air and fading light. In the pond at picnic site 5, the first Brown trout (Salmo trutta) of this season has returned to the lower-canyon stream. A brushy tree limb has been removed, so the trout does not have the same cover as last year (Oct. 21st), but there is a bare six inch diameter tree trunk in the pond’s bottom. The trout uses this scant cover and goes for a hiding place in between the bottom of the log and the stream bed. The presence of the trout is related to shade provided by 100 foot canopy trees like Box Elder and Narrowleaf cottonwoods (Lanner 1984). Trout prefer cool water and the exposed stream, the flood retention ponds both below Guardhouse Gate and above at mile 3.0 may have become too warm for them. Now they seek cool pools shaded by the forest and where the stream has deep, vertical banks.

As I pass the watercress field in the tunnel seep below picnic site 6, I notice two eyes starring back from the darkness. A small North American porcupine (Erethizon dorsatum) is sitting at the edge of the seep, contentedly grazing on the watercress. I have not seen a porcupine in the lower canyon for about two decades, and I had thought most of them to be driven out of the upper canyon above mile 4.0 by the increasing drought (Nov. 2nd). This porcupine, like its species, is docile and unafraid. Because of it quills it has few serious natural enemies, although quills have been found in mountain lions, coyotes and bears. Eventually, it becomes wary of me and effortlessly climbs a nearby forty feet tree. They eat green plants, like clover, leaves, and the bark of trees (Hayward 1948 at 494, Spencer 1964). Such discoveries of old animal friends raise my spirits. They have not been driven from Salt Lake canyons. In the fading twilight, bicyclists streak out of the canyon illuminating their way with blinding LED lanterns.

* * * *

There are four primary methods of seed dispersal: by wind, by water, by gravity, and by animals. Animals move seeds by several methods. Epizoochory is the movement of seeds, like the Foxtail, by attaching to the outside of an animal. Endozoochory is the movement of seeds by animals internally, i.e. – eating of seeds by birds and mammals followed by the seed’s excretion distant from the parent. More recently anthropochory, the movement of seeds by humans, has radically changed the canyon and western habitats, by moving seeds across oceans and continents.

In 1993, now Utah State University of Utah botanist Eugene Schupp noted that the benefit to a plant that an animal disperser provides is a probability function of the quantity of seeds dispersed and the quality of the seeds produced (Schupp, Jordano, and Gómez 2010, Schupp 1993). Quantity of dispersal depends on the number of disperser visits and the number of seeds dispersed on each visit. The quality of seeds produced depends on either its treatment in an animal’s digestive tract or quality of seed deposition, i.e. – some animals are sloppy eaters and drop seeds close to the parent and others efficiently eat all seeds and move them a significant distance from the parent. Combining these factors gives a seed dispersement effectiveness index, and that single dimensional index can be used to relatively rate the importance that the many animals that consume a plant’s seeds contribute to the plant’s reproduction. For example, any single tree species many have five or ten bird species that eat and disperse its seeds.

Seed dispersal matters to the recuperation of forests. Where forests, like the canyon’s Gambel’s oak chaparral or stream-side association, are long-lived and mature, bird dispersers have little effect on a forest’s health. But when a forest is disturbed, for example by fire or clear-cutting, a forest cannot re-colonize unless it also supports a healthy bird population that can distribute its seeds (Howe and Miriti 2004, Martínez and García 2017). This process works in reverse. Bird dispersers can be lost, and eventually this may lead to the loss forests that they visit (Howe and Miriti). This underscores the need to preserve bird habitats on a continental scale, since the avian distributors of seeds that will help City Creek Canyon’s oak and montane forests recover from a future fire, may overwinter in Central American forests (May 22nd, May 23rd and May 24th).

* * * *

On July 17th, 1915, the U.S. Weather Bureau installed an advanced stream flow measuring gauge at the High Line Water Tanks in Pleasant Valley (Salt Lake Herald). On July 17th, 1908, the Salt Lake Telegram reported that the city prison road work gang had labored for 18 months to improve City Creek Canyon Road. On July 17th, 1888, ten families had set up tents for cool summer camping in City Creek Canyon (Salt Lake Herald). On July 17th, 1887, the Salt Lake Herald reports that several families have moved into tents in and for the cooler air of City Creek.

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January 18, 2017

January 18th

Filed under: Elk, Mountain lion, Mule Deer, People — canopus56 @ 8:41 pm

Mountain Lion

5:00 p.m. The inversion air continues to thicken, and much of the City has been swept through by a virus. I cannot escape the bad air, but by milepost 1.5 and at about 5,100 feet in elevation, I am breathing easier. The temperature feels warmer overall, but between picnic site 7 and 8, where yesterday the stream was covered with a thin pane of water glass, the ice is thickening again and becoming a frosted white. Below picnic site 7, where roots stick out of the bank, rising water vapor collects on them in the form of white rime. Surface air is calm, but three thousand feet above, cirrus clouds with long linear wisps are rapidly moving over the land. Like water vapor of the stream, the wisps are ice crystals forming and evaporating but at a higher altitude.

Yesterday evening, on local neighborhood social media, a woman reported hearing a mountain lion screaming in the bushes of lower City Creek Canyon below Bonneville Boulevard. For the last four days between Guardhouse Gate and mile 0.3, there have been a herd of four mule deer regularly grazing during the day on the south canyon side across the stream, and it does not surprise me that a mountain lion came down to consume a deer. Last summer on June 22nd, 2016, a woman who frequently runs in City Creek reported to the guard at the gate that she had seen a mountain lion just off the road in Pleasant Valley (Personal observation). The next day, City Watershed Patrol posted several “cougar sighted” warning signs along the road; this is their usual practice in such cases. Last night’s social media report is one in a long-list of regular cougar sightings in the canyon.

Mountain lions have been here since before the 1847 arrival of the Euro-American colonists. Those pioneers built a fort in the form of stockade consisting of 29 log-cabins on what is now called Pioneer Park near 300 West and 300 South in Salt Lake City (Bancroft, 277). The pioneers reported the fort also was harassed by “wolves, foxes, and catamounts” (id). “Catamount” is a term used by easterners for eastern mountain lions, and the term “mountain lion” came into use after Euro-Americans came to the West. Other predators dangerous to humans were present. In 1847, pioneer Lorenzo Young noted that he “spread some strychnine about [the fort], and in the morning found fourteen white wolves dead” (Bancroft, 277, ftn. 8). On January 7th, 1903, predator bounty hunter George McNeil reported that “I killed two wildcats up there [in City Creek] a few days ago” (Salt Lake Telegram).

Mountain lions continue to occupy the canyon today, and City residents are fortunate in this regard. One-hundred and fifty years ago in Thoreau’s “Journal,” he lamented that eastern mountain lions, lynx, wolverenes, bear, moose, deer, and wild turkeys had all been exterminated from Concord, Massachusetts (Journal, March 23rd, 1856). Except for lynx and wolverenes, all of the those animals can either be regularly seen in the canyon today, or in the case of the black bear, I saw its track in the snow during February 2016. I count possibility of rarely glimpsing a mountain lion a similar positive expectation. Although no longer in the canyon, in 1978, I saw a lynx in the nearby Oquirrh Mountains and in the mid-1980s, a wolverene below O’Sullivan’s Peak in Big Cottonwood Canyon. But this privilege of regularly seeing moose, deer, elk, and wild turkeys in the City Creek canyon does not come without a price.

In the winter, cougars feed principally on mule deer and in the spring, they turn to newly birthed mule deer and elk. From record-keeping beginning in 1970, there have been no known fatalities in Utah, although a few have occurred in California (Wikipedia). Not all encounters are fatal. In over thirty years in the Wasatch, I have been tracked only once by a mountain lion, but that was during a solo hike below Deseret Peak in Tooele County during the midst of summer. A small rock and some shouting turned the lion packing in the other direction. The ratio of non-fatal attacks to deaths is unknown, since attacks or attempted attacks, like the one I experienced, are not reliably reported, and traveling with a dog in the backcountry is said to attract and to increase the risk of encountering a mountain lion.

Beyond the obvious overriding human concern over the risk to children walking in the canyon, another of the City’s practical concerns is liability and risk management; it has a duty to warn of wildlife in the area. Hence, the notice posted in the canyon last summer. In 2007 in Utah County during the summer, a bear tragically took and killed a small child at a Utah State picnic area, and in 2015, the state ended up paying a 2 million dollar judgment for failing to warn picnickers about their knowledge of other recent sightings of bears near the picnic grounds (Salt Lake Tribune, Feb. 24, 2015). After the 2007 incident, the “danger, watch out for bears, moose, and mountain lions” signs started being posted at Guardhouse Gate in City Creek. Since then, all levels of government, including the City Watershed Patrol, post notices of recent sightings of any predator, and properly so.

The notices allow people to keep a closer eye on their children and pets, until the cat moves back up the canyon. The cat probably will follow the deer back up in a couple of weeks as temperatures rise and deer herds move higher. Anecdotally, there have been many more anterless elk hunters in the canyon this winter (including two yesterday) as compared to the 2015-2016 season. Hunters may have been more successful in the canyon and that may have put more pressure on the one or two mountain lions that hunt between Ensign Peak and Lone Peak, forcing them to come lower towards the city. The anterless elk hunt ends on January 31st, and the hunters leaving will lessening competition for the mountain lion’s up canyon food source.

There also is a good practical reason for mountain lions to be in City Creek, at least above Bonneville Drive, even though there is some risk to people from them continuing to reside in their historical hunting range. Deer inflict relatively more injury to people and cars in the form of automobile accident collisions, and mountain lions are more effective at controlling deer populations than human hunters. Where I live near the City cemetery, I usually see or hear one early morning collision a year between a car and a deer. Last year, speeding young people, who were also drunk, hit a deer, and the deer walked off but died a block away. The university students were unharmed, but the deer did significant damage to the front of their still drive-able car. Younger, inexperienced yearling deer just do not know the right way to run when startled. The ones that make it to an age of 2 years old figure out that they have to run into the dark and not into the light. Conversely, mountain lions do not come down into the Avenues, or so I thought. Today, another neighborhood resident posts that two years ago at Christmas, she saw a mountain lion in the City cemetery. Mountain lions fear people since they, like the mule deer and the elk, are subject to an annual hunt, but they do still roam the canyon.

Recent 2016 research suggests that mountain lions provide a substantial economic and social benefit by reducing deer collisions with human vehicles. Gilbert at the University of Idaho and colleagues studied the impact of re-introducing and re-colonization of mountain lions into North and South Dakota. Mountain lions were extinct in both states prior to 1994, but were then re-introduced, and by 2004, the lions had re-colonized most of their former range. Between 2004 to 2012, deer-vehicle collisions in areas with and without mountain lions decreased 20% in North Dakota (to 0.22 per 100,000 people) and 50% in South Dakota in areas with and without mountain lions (to 8 per 100,000 people). This benefit may outweigh the risk of living on an urban nature interface with their presence. In short, one coyote or one mountain lion in the nearby canyon can mean many less deer grazing on your Avenues or Capitol Hill shrubbery or stepping out in front of your car during a 2 a.m. run to a convenience store.

In Thoreau’s “Journal” on January 18th, 1859, he sees more blue snow shadows. On January 18th, 1859, he records thick frost rime covering trees. On January 18th, 1860, Thoreau describes winter feeding habits of chickadees: they pry up the bark of pines looking for insects underneath.

On January 18th, 1941, the Utah State Road Commission proposed to build an improved road from Fort Douglas along 11th Avenue, then across a newly constructed bridge over City Creek Canyon, and then on to the airport (Salt Lake Telegram). On January 18th, 1927, the University Hiking Club reported that 20 of its members hiked to the top of Black Mountain and then slid down its backslide to [Upper] Rotary Park (Utah Daily Chronicle). On January 18, 1909, the Salt Lake Telegram reported that Ms. Helen Boes became the first Utah women known to have killed a bear. A captured wild bear was released in City Creek Canyon and a party of thirteen hunted the bear assisted by dogs. The bear escaped City Creek but was hunted down on the western slope of the ridgeline above the Beck Street Hot Springs (id). On January 18th, 1895, City Mayor R. N. Baskin proposed that the City build an independent power plant driven by City Creek water, after it was alleged that a private electric company had been providing only one-half the candle power to city lighting as required by its public contract (Salt Lake Tribune). See February 1st, 1895.

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