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.

April 11, 2017

April 10th

Time Limit

1:30 p.m. The canyon’s ridgeline retains a slight covering of snow, but it is heavier on Black Mountain and Scott’s Hill. The highest mountains on the Wasatch Front Range received two feet of new snow, but the gauge station at Louis Meadows has only a small uptick of one-inch in equivalent water precipitation, and this suggests at most two or three inches fell in upper City Creek Canyon. Some trees respond by covering the road with small broken twigs with leaves. Freezing overnight temperatures retain this snow, but the cool day is overwhelmed by the new bright sunlight of spring. Sunrise begins at six a.m. and sunset arrives at eight p.m., but it is the new height of the noon sun that gives spring its force. It is still unsuccessful at pushing back on winter’s control, but the tide turns in its favor. The noon-time light is simply so much more brighter than on vernal equinox almost three weeks ago. It almost hurts the eyes, and the intense light reminds that summer will eventually arrive. Under this light, what I had supposed was the over-wintering yellow fruit of the canyon’s ubiquitous poison ivy patches burst in small flowers. A single cultivar of purple grape hyacinth (Muscari armeniacum), which is common in the city, blossoms along the first mile road.

Yesterday, there was a large predator scat pile on the road. Predator wildlife scat is easily distinguished from the feces of domestic dogs that also frequent the road because predator scat is full of the fur of its mouse and squirrel prey. Predator scat also ends in a narrow tip, unlike the rounded ends of domestic dog scat. Given the size of the pile, it may have been deposited by a mountain lion. But today, as I leave the car at Guardhouse Gate parking lot, on the heavily traveled canyon road between Bonneville Drive and the lot, a coyote expertly bonds down a steep slope, crosses the stream, and bolts into the thicket on the far east side of the stream. Come to think of it, I have not seen two rock squirrels, first viewed in the parking lot about a week ago, for some days. From thickets on the side of the road, Black-billed magpies and other song birds are heard.

The coyote, rock squirrels, mice, and I share a common bond of all mammals as a result of our common genetic heritage. Our time in the canyon and on the Earth is limited by a pre-programmed number of heart beats: about one billion for most mammals and uniquely about 3 billion for humans. Like the canyon’s coyote, my time in the canyon a mortal limit. I only have at most 700,000,000 heart beats left to live and to see the canyon.

* * * *

In Thoreau’s “Journal” on April 10th, 1841, he remarks “How much virtue is there in simply seeing?” On April 10th, 1853, he notes that saxifrage is blooming.

* * * *

The hearts of mammals regardless of size beat between 1.29 and 0.17 billion times (mean: 0.73 +- 0.56) over their life (Levine 1997, Cook 2006). For humans, lifetime heart beats average about 3 billion (Cook). But adjusting for heart rate, body mass, and longevity, over a lifetime, the heart of a 2 gram mouse delivers the same amount of total oxygen per unit of mass as that of 100,000,000 gram blue whale (id). As the mass of mammals increase, their heart rate decreases and their longevity increases. The 2 gram mouse’s heart beats 500 times per minute, but the mouse only lives one year. A loin’s heart beats at about 50 times per minute, but it can live for sixty years. This well-defined log-linear relationship between resting heart rate and longevity varies systematically from the small (mouse, hamster, and rat) to the large mammals (horse, lion, and elephant), except for humans (id). Plotting the log of resting heart rate or metabolic energy per kilogram of mass against longevity for various mammals gives a nearly straight line (Atanasov 2007, Cook 2006), but the 3 billion beats of the human heart for 80 years of life sits as a distant outlier from the other mammals (Cook 2007). The 2 billion extra beats allotted humans, like our brains, sets us apart from other mammals. But for both humans and other mammals, the above suggests that at cellular level, there is a genetically pre-programmed length to all mammalian life.

It would wrong to conclude that human life can be extended by not exercising because the hearts of people who do not exercise will beat less. The relationship between a lower resting heart rate, general good health, and increasing longevity is well-known (Cook). For a person who does not exercise and has a resting heart rate of 90 beats per minute, their heart will beat about 3.8 billion times over eighty years. For a person who exercises for two hours per day at 110 beats per minute and who has a resting heart rate of 70, their heart will beat 3.1 billion times over eighty years, or about 80 percent of the effort of the non-exercising person. For high functioning athletes with resting heart rates of 50 beats per minute, their hearts will beat about 2.3 billion times in eighty years, or about 60 percent of the effort of the non-exercising person. For unknown reasons, ultra-fit humans, who have the lowest amount of body fat and the lowest body mass indices (BMI), have higher mortality rates similar to the obese and higher than the ordinarily fit of persons of normal weight (Lorenzini 2014). Lorenzini’s review should be read cautiously. Higher mortality of abnormally low-weight persons may be a cofounding artifact of terminally-ill patients losing weight as they expire. But the implications of exercise for not developing debilitating health problems after age 50 are self-evident, since the health of other organs depend on a healthy blood circulation provided by the heart. Among older men, exercise has a protective effect against developing cardio-vascular disease and thus, reduced general circulation and increased mortality (Kodama). This cardiac protective effect is known to be dose dependent amongst men with Type 2 diabetes (Church). More exercise provides more protection. This is only one physical benefit of several types of benefits from being actively connected to nature and the canyon.

* * * *

On April 10th, 2007, the AAA as part of its Great Battery Roundup program, pledges a $2 donation for City Creek Canyon Rehabilitation for every automobile battery delivered to the club (Salt Lake Tribune). On April 10th, 1927, Frank Robinson, a student from Coalville, won the annual marathon up City Creek Canyon (Salt Lake Telegram). On April 10th, 1916, L.D.S. Church members held a running race up City Creek Canyon. Non-Mormons, called “gentiles” by the Mormons, held a separate race along the East Bench (Salt Lake Telegram). On April 10, 1911, Water Commissioner Frank Matthews announced that dogs will not longer be allowed in City Creek Canyon unless they are kept on a leash because dogs have been swimming in the water supply (Salt Lake Telegram, Salt Lake Tribune, April 11, 1911). On April 6th, 1906, the Salt Lake Tribune reported that “streams of people” went up City Creek for recreation by horse carriage, on foot, and by bicycle (Salt Lake Tribune). On April 10th, 1898, the Utah Forestry Association and the City made plans for the experimental planting 300 ash trees in moist areas of City Creek Canyon (Salt Lake Tribune).

December 7, 2016

December 8th

Filed under: Birds, Coyote, Deer Mouse, Guardhouse gate, People, Pleasant Valley — canopus56 @ 11:00 pm

Three Types of Hunters

3:30 p.m. On December 7th, daytime temperatures are in the low twenties, but it is a clear sunny day. I am continuing making an inventory of bird and insect nests in the canyon. Three hunters are on the prowl in the canyon.

At the up canyon end of Pleasant Valley Reservoir along the trail parallel to the road that leads back to picnic site 11, I find a set of mule deer tracks in the snow interspersed with canine tracks. Canine snow tracks are distinguished from mountain lion tracks by the presence of claws and the number of rear lobes on the paw print. Canine tracks have claws; felines do not. Canine tracks have two rear lobes on their paws; felines have three (Michigan Dept. of Natural Resources). This are canine tracks but it is too far from the road for them to be domesticated dogs. Therefore, I suspect the canine tracks are from a coyote.

Near mile 1.2, two hunters are walking down canyon carrying a pack between them. They are armed with both bows and rifles. The anterless elk hunt remains open through January 31st, 2017, and they describe how they and a third hunter have taken two elk up the canyon. Our encounter underscores the wastefulness of this hunt. The city prohibits vehicle access except by special request and the City prohibits State permitted anterless elk hunting in the canyon although, the City allows it by special discretion of the water treatment plant operators. To muddle matters further, their are two classes of State issued anterless elk permits: regular permits where the user may hunt on public lands and special elk control permits where a hunters may not hunt on public land. Because of the City rules, the hunters are hand-hauling perhaps 50 lbs of meat from a 200 or 300 lb. elk for  6 to 8 miles out of the canyon. The remainder of the carcass is left to rot. Their hunting companion did obtain permission to bring a car into the canyon, and he jets by dragging a snow sled that also contains a sack of meat.

At mile 0.6, I instinctively look up in response to hearing a shriek. A raptor is crossing the canyon, but it is to fast and too high identify.

Each of these three hunters has their own assessment of what is valuable and each have their own objectives. This affects how each sees the canyon.

On October 23rd, I talked with a clerk at City Department of Public Utilities. She states that there is only one City permitted hunting season in City Creek Canyon – the regular rifle deer hunt that ends October 31st. I indicate that I have seen hunters regularly during the Utah State Division of Wildlife Resources’ December anterless hunt and during its November 30th bow hunt. She states that if I see rifle hunter’s during the anterless hunt in the future, I should call the Department and they will send up the police to get them out. But then she qualifies the restriction by stating that the plant manager may be let people hunt at his discretion. This confusing state of affairs is complicated by modern technology that provides cell phone applications that allegedly map all permitted hunting areas. I surmise that some of the hunting that I have seen during December in the canyon is in fact illegal.

This regulatory confusion becomes apparent when I reach Guardhouse Gate where a luxury home owner on the bench above the canyon entrance is distraught over the scoped high-powered hunting rifles that the two hunters have lain on the ground while waiting for a ride. I talk with the hunters to assuage her overstated fears. They claim to have taken the two elk outside the drainage north of Bountiful, and then quartered carcasses and dragged them over the ridge and out the City Creek Canyon side. They even pull out their cell phones to show me maps that their hunting area was “legal”. I suspect that they are being deceptive, since their clothing is not wet and I have hiked the route many times that they claim to have taken. Part of the route is a one and one-half mile trek through up to eighteen inches of snow with no trail. They would have had to have post-holed in snow up to their calves for at least one-half mile. One has to bushwack about three-quarters of mile through dense thickets. Their story is not believable, but the watershed canyon patrol also saw them and let their companion’s vehicle into the canyon, so I let the matter go, congratulate them on a successful hunt, and give some background to the distraught homeowner. In order to reduce such conflicts, I write the maker of the popular hunting cell phone application that these hunters were using and ask them to add the additional City hunting restrictions to their online maps.

Even today, with the wind where temperatures drop into the teens, there are about twenty runners and walkers on the canyon road. The Utah Division of Wildlife Services website indicates that a total of 40 anterless elk permits were available for the Salt Lake County hunting zone, including City Creek Canyon (Utah Division of Wildlife Services, 2016).

My own feeling is although the canyon is a multiple-use area, these winter hunts are simply wasteful since the City is not granting organized, permitted vehicle access in order to give the watershed a rest, and it is not possible to remove all of the meat taken. Today, these three human hunters have left perhaps five or six hundred pounds of carcass to rot in the backcountry. Given the change in recreation use mix from hunting to other dispersed recreation, these winter hunts are arguably not an appropriate multiple-use balance.

The two other non-human hunters in the canyon today generate no such controversies.

In Thoreau’s “Journal” on December 8th, 1855, he observes that due to the winter cold, nature surrounding his home is empty of both mammals and birds. In Thoreau’s “Journal” on December 8th, 1850, Thoreau records the first significant snow of the season.

September 21, 2016

September 7th

Filed under: Coyote, Mammals, Mule Deer, People — canopus56 @ 12:59 am

Coyote Friend

6:30 p.m. While jogging near mile 0.4, I hear something moving in the brush. I freeze and remain silent. Across the stream, small female coyote is noisily picking its way through the brush and towards the stream. She cannot see me because the stream is several feet below the roadbed and its view of me is blocked by the bank. She did not hear me because the coyote itself was making so much noise walking across dry leaves. This is the closest that I’ve been to a coyote in my life. Usually they are seen several hundred feet away crossing an open meadow.

The coyote spends a couple of minutes drinking at the stream. She finishes and then works her way back up the opposite bank. I make a small noise, she stops, and turns around to look me over. The coyote has large erect black fringed ears that stick out perpendicular from its narrow head. The snout is also narrow and has a delicate yellow side coloring. The eyes are bright deep yellow. Beneath the jaws, the neck hair has a subtle yellow black molted pattern that I do not see in photographs of other coyotes. In her eyes I see canine intelligence. It is the same dog intelligence that I see in the eyes of a friend’s domestic border collie. She betrays no fear or aggression, other than a few raised hairs on her back. She is relaxed and sniffs the surrounding leaves while keeping one eye on me. We both get bored of this game after a minute or so, and we go our separate ways. I wonder how many times in the past she has sat quiet and unseen in the brush watching myself and other joggers go by.

Coyote are a predator of mule deers. They principally take deer fawns, and studies indicate that coyote predate between 9% to 50% of annual deer births. However science has been unable to determine whether their predation significantly impacts the deer population. This is because of the confounding effect of compensatory versus additive predation. In compensatory predation, the coyotes take deer fawns that would have died from from other natural causes. In additive depredation, the coyote takes a fawn that would have survived those other natural causes of mortality.

Utah Division of Wildlife does not regulate the taking of coyotes because they are not classified as a “beneficial” species. In addition, the Utah Legislature funds the Division’s program that pays a $50 bounty for taking a coyote, and each year about 7,000 hunters claim the reward. Another $140,000 is set aside for contract hunters who take another 260 coyotes at an average cost of about $600 each. A Wildlife Division map indicates that three or four coyotes have been taken in City Creek Canyon between 2007 and 2014. The program is designed to make more deer available for the annual deer hunt, but the scientific basis for this practice is open to question. It is common sense that coyotes take immature deer, but even though Utah, Idaho, Wyoming and Colorado all fund similar coyote removal programs, the national decline of deer population continues in both states that have and do not have removal programs. This suggests that the decline of the mule deer population is related to loss of habitat or climate change and not to the coyote. Mathematical biology for managing wildlife populations is a complex topic, and due to the uncertainty in measuring populations, is an inexact science.

The role of natural predators is also a matter of perspective. By 1900, unrestricted hunting had reduced pre-colonial deer populations in the United States from about 40 million down to about 5 million individuals. Through management by 2000, the national deer population was restored to its pre-colonial level. Since then national deer populations have been on a steady but slow decline. In Utah, the mule deer population peaked in 1992 at about 350,000 individuals and since the severe winter of 1993, the population has fluctuated between about 275,000 and 325,000 individuals.

My own uninformed impression is that the primary predator of Utah mule deer is the SUV, and that this mangy, malnourished coyote in City Creek Canyon is being given more credit by hunters than is warranted.

September 20, 2016

August 21st

Filed under: Birds, Coyote, Eagle, Gambel's Oak, Mammals, Meadow Mile 1.3, Plants, Wild Turkey — canopus56 @ 11:16 pm

A Family of Turkeys

4 p.m. At mile 1.7, the presence of a group of wild turkeys is given away by a single clump of scat. At this same location in mid-July, a breeding pair were walking through the Gambel oaks followed by a brood of eight or nine chicks. Unexpectedly, wild turkeys do well in this Great Basin shrub oak habitat. In the canyon, the Gambel oak forest covers the northern slope and continues over into the much larger Bountiful drainage. The dense oaks provide protection their principal predators: hawks and eagles from above and coyotes from below. The oak’s acorns provide an ample food supply. But they’re rarely seen except in late January and February, when the winter snows drive them near the road near mile 2.2. Then they can be seen in flocks of up to twenty individuals.

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