Diurnal Schedule Research Articles

Evaluating Low Cost Sensor Performance for Use in Industrial Internet-of-Things Platforms: Distributed Sensing Solutions for Urban Area Air Quality Health Monitors

The “Array of Things” project in Chicago, IL (U.S) is a ‘smart-cities’ joint initiative funded by the National Science Foundation and involving a partnership between Argonne National Laboratory, the University of Chicago, and the City of Chicago [1]. Several hundred of these platforms are distributed about the city of Chicago and each incorporates seven low-power electrochemical gas sensors for measuring the air quality health of the city. This collection of nodes is the foundation of an Industrial-Internet-of-Things, managed by a public institution, for the benefit of the surrounding communities. It presents a unique opportunity to develop smart sensor algorithms to calibrate these low-cost sensors, thereby providing meaningful and accurate data to map and identify sources of air pollution or to inform the communities of poor air quality days.To create the numerical calibration methods, ozone (O3), nitrogen dioxide (NO2), and carbon monoxide (CO) gas sensors are compared to reference grade monitors, with data collected between March 2018 and June 2019. The gas sensor sub-assembly board was calibrated in the labs at KWJ Engineering, Inc. (Newark, CA) in October 2017. The AoT node was installed and began operating at the EPA ComEd measurement site in Chicago (7801 S Lawndale Ave, Chicago, IL 60652), with help from Pinaki Banerjee of the Cook County Department of Environment and Sustainability. CO reference instrumentation was provided by Max Berkerlhamer of the University of Illinois – Chicago; NO2 and O3 data were from the EPA instruments run by Cook County. Sensor data is collected at 5-minute intervals, while reference data is reported at 1 hour (NO2/O3) and ½ hour intervals (CO). Over the course of 15 months, the reference data showed peak NO2 and O3 values of about 90 ppb, typically with opposite diurnal cycles. During the four months of CO reference monitoring, the range of recorded values were between 150 and 1,500 ppb. To reach these lower detection limits with low cost sensors, methods to remotely zero and span must be developed to overcome the effects of time, as well as outdoor temperature, humidity, and pressure extremes.The main advantage to EPA or research grade instrumentation is the ability to zero and calibrate the equipment at regular intervals. For instance, an EPA site may report an 8-hour moving average for O3 and/or NO2, and this equipment may be zeroed and calibrated on a weekly or daily schedule. For an air monitor mounted on a telephone pole, or internal to a publicly accessible structure (such as a bus stop), calibration methods requiring gas exposure are not feasible. As an alternative method, numerical zeroing using known or anticipated low values can enable an estimation of a zero. These low points can be timed to a weekly or sometimes a diurnal schedule. EC sensors have a typical baseline exponential sensitivity to temperature, which can change over time. Methods to predict this change for the CO sensor increased the R2 correlation from 0.14 when using a static calibration factor to 0.72 when using a time dependent dynamic factor. For determining the appropriate numerical span values ‘nearest neighbor’ methods can be implemented, using either a publicly available reference station, such as an EPA monitoring site, or similarly timing to a known or expected high point. Also important to the sensor stability are averaging methods that can respond quickly to environmental releases of pollutants. Approaches to these methods depend on the targeted gas as well as the sensors' chemistry including the effects of interference from other gasses typically present in air. For example, in this system the NO2 and O3 co-dependence is also shown to change with time. For the NO2 sensor the baseline (diurnal minimum) should decay over time, similar to the CO sensor. However, with increasing sensitivity to O3, the baseline will start to increase, and this pattern can be used to infer the increasing sensitivity to O3.While improvements to sensor design will mitigate some of the shortcomings of low power sensors, this work highlights important numerical methods, and will provide examples to improve the integrity of low-power sensing nodes for future distributed gas sensing networks, allowing for wider implementation of smart-city platforms at a lower cost to the public for implementation.[1] Catlett CE, Beckman PH, Sankaran R, Galvin KK. Array of things: a scientific research instrument in the public way: platform design and early lessons learned, Proceedings of the 2nd International Workshop on Science of Smart City Operations and Platforms Engineering, 26-33 (2017) Figure 1

Generalizability of A Neural Network Model for Circadian Phase Prediction in Real-World Conditions

A neural network model was previously developed to predict melatonin rhythms accurately from blue light and skin temperature recordings in individuals on a fixed sleep schedule. This study aimed to test the generalizability of the model to other sleep schedules, including rotating shift work. Ambulatory wrist blue light irradiance and skin temperature data were collected in 16 healthy individuals on fixed and habitual sleep schedules, and 28 rotating shift workers. Artificial neural network models were trained to predict the circadian rhythm of (i) salivary melatonin on a fixed sleep schedule; (ii) urinary aMT6s on both fixed and habitual sleep schedules, including shift workers on a diurnal schedule; and (iii) urinary aMT6s in rotating shift workers on a night shift schedule. To determine predicted circadian phase, center of gravity of the fitted bimodal skewed baseline cosine curve was used for melatonin, and acrophase of the cosine curve for aMT6s. On a fixed sleep schedule, the model predicted melatonin phase to within ± 1 hour in 67% and ± 1.5 hours in 100% of participants, with mean absolute error of 41 ± 32 minutes. On diurnal schedules, including shift workers, the model predicted aMT6s acrophase to within ± 1 hour in 66% and ± 2 hours in 87% of participants, with mean absolute error of 63 ± 67 minutes. On night shift schedules, the model predicted aMT6s acrophase to within ± 1 hour in 42% and ± 2 hours in 53% of participants, with mean absolute error of 143 ± 155 minutes. Prediction accuracy was similar when using either 1 (wrist) or 11 skin temperature sensor inputs. These findings demonstrate that the model can predict circadian timing to within ± 2 hours for the vast majority of individuals on diurnal schedules, using blue light and a single temperature sensor. However, this approach did not generalize to night shift conditions.

Longevity of Enhanced Geothermal Systems with Brine Circulation in Hydraulically Fractured Hydrocarbon Wells

A simple, semi-analytical heat extraction model is presented for hydraulically fractured dry reservoirs containing two subparallel horizontal wells, connected by a horizontal fracture channel, using injected brine as the working fluid. Heat equations are used to quantify the heat conduction between fracture walls and circulating brine. The brine temperature profiles are calculated for different combinations of fracture widths, working fluid circulation rates, and initial fracture wall temperatures. The longevity of the geothermal heat extraction process is assessed for a range of working fluid injection rates. Importantly, dry geothermal reservoirs will not recharge heat by the geothermal flux on the time scale of any commercial heat extraction project. A production plan is proposed, with periodic brine circulation maintained in a diurnal schedule with 8 h active production alternating with 16 h of pump switched off. A quasi-steady state is achieved after both the brine temperature and rock temperature converge to a limit state allowing fracture-wall reheating by conduction from the rock interior in the diurnal production schedule. The results of this study could serve as a fast tool for assisting the planning phase of geothermal reservoir design as well as for operational monitoring and management.

SURVEILLANCE RADAR DATA ON NOCTURNAL BIRD MIGRATION OVER ISRAEL, 1989–1993

ABSTRACT The circular-scanning approach radar at the Ben-Gurion International Airport has been a major tool in studying nocturnal migration over Israel during 1989–1993. Nocturnal migration was studied by photographs of the radar screen. Each photo was a continuous 10-min exposure, taken every half hour, from nightfall to dawn. The photographs allowed determination of direction, magnitude, schedule, and velocity of migration. Comparison of results from five years of observations showed that the diurnal and seasonal schedule of nocturnal migration, as well as the variation in direction during the night, exhibit a pattern that repeats itself yearly.

Activity patterns of brown bears (Ursus arctos) on the Deosai Plateau, northern Pakistan

The daily activity of Himalayan brown bears (Ursus arctos) in the Deosai National Park, northern Pakistan, was investigated over a period of four years (1993-1995 and 1999). Bears spent the largest part of the day feeding, followed by moving about. Resting and other activities combined formed a substantial part of the diurnal schedule. No significant difference in the daily time budget of males and females could be demonstrated, but subadults were found to move about significantly more than either adults or cubs and yearlings. Aberrant activity patterns observed during the summer of 1999 can be attributed to human disturbances caused by the Kargil war between India and Pakistan.

1-Butanol Removal from a Contaminated Airstream under Continuous and Diurnal Loading Conditions

A polysulfone microporous membrane module was investigated for control of 1-butanol-contaminated gas streams. A diurnal loading condition, using two different butanol concentrations, was used to simulate startup and stop conditions associated with shift work. The membrane module was also used to remove 1-butanol from air under continuous loading conditions in a bioreactor. The reactors were seeded with a mixed bacterial consortium capable of butanol biodegradation. Biokinetic parameters for butanol utilization were determined for the culture to be a maximum specific utilization rate (k) equal to 4.3 d−1 and a half saturation constant (Ks) equal to 8.9 mg L−1. A biofilter running only with diurnal loading conditions giving a “40-hr workweek” had an average 1-butanol removal rate of 29% (111 ppm, 74 gm−3 hr−1) from a 350-ppm influent at the end of an 8-hr operational day. End-of-day removal varied between 4 and 67% during the operational period. With continuous steady-state operation followed by placement on a diurnal loading schedule and influent butanol concentrations increased to 700 ppm, butanol removal averaged 38% (269 ppm, 145 gm−3 hr−1). Under continuous loading, steady-state conditions, 1-butanol removal from the airstream was greater than 99% (200 ppm, 73 gm−3 hr−1). These results suggest that the bioreactor can be operated on a diurnal schedule or 40-hr week operational schedule without any decline in performance.

The Influence of Air Temperature and Sunlight Intensity on Mate-Locating Behavior of Pieris rapae crucivora

It is considered that the mate-locating behaviors of ectothermic insects are constrained by the ambient thermal conditions, since the flight ability depends on the body temperature. However, since ecological factors also influence the mating behaviors, the flight ability would not necessarily determine the time schedule of male mate-locating flight. To reveal how the ambient thermal conditions influence the mating behaviors, we investigated the association of air temperature and sunlight intensity with the diurnal schedule of female-searching behavior in male P. rapae crucivora. In the early morning, the proportion of female-searching males to basking males increased as the air temperature and sunlight intensity increased. The air temperature was also associated significantly with the diurnal schedule of male female-search on 7 of 8 observation days. The number of female-searching males reached the peak when the air temperature was between 24 and 29 degrees C. On the other hand, the sunlight intensity did not account for the diurnal schedule of male female-search. The associations between the sunlight intensity and male female-search were not consistent among different days. When the air temperature was roughly constant, however, the sunlight intensity was correlated significantly with male activity of female-search. The regression of male activity of female-search as a function of sunlight intensity was improved, when it was assumed that the sunlight intensity influenced male behaviors with a delay of 1 to 4 minutes, and when it was assumed that the mean intensity of sunlight for 1 to 9 minutes influenced male behaviors.

Differential effects of aromatase inhibition on luteinizing hormone secretion in intact and castrated male cynomolgus macaques.

To understand the role of central aromatization in feedback regulation of LH in nonhuman primates, we treated adult male cynomolgus monkeys with the aromatase inhibitor, 1,4,6-androstatriene-3,17-dione (ATD). We measured LH, testosterone (T), and ATD in systemic sera of blood samples drawn on a diurnal schedule (0900 and 2100 h). Each animal was bled for 4 pretreatment days from a femoral catheter after which they were divided into the following treatment groups: castrated (Cx), n = 2; Cx + T, n = 6; Cx + T + ATD, n = 6; Cx + ATD, n = 3; and sham operated + ATD, n = 3. Silastic capsules or packets containing T or ATD, respectively, were placed sc between the scapulae at the time of Cx or sham treatment. In T-treated animals, T (20 micrograms/kg body weight) dissolved in propylene glycol was injected im at 2100 h to mimic the diurnal rise of T observed in nonhuman primates. Animals were bled for 2 weeks after which they were killed, and selected brain areas were analyzed for aromatase activity and cytosolic and nuclear androgen receptors. Animals treated with ATD had significantly reduced levels of aromatase activity in selected regions of the hypothalamus, preoptic area, and the amygdala (P < 0.05). Even though ATD inhibited brain aromatase activity, it did not prevent the negative feedback actions of T on LH secretion after Cx. In addition, ATD by itself inhibited LH secretion after Cx and activated brain androgen receptors. These latter effects of ATD seemed to have been mediated through a metabolite. In sham-operated intact males, ATD produced variable surges of LH that were accompanied by elevations of T in the systemic circulation. These differential effects of ATD in intact vs. castrated animals demonstrate the importance of selecting the proper model system to study LH control mechanisms. In the intact animal, aromatization seems to play a role in regulating LH secretion, but the postcastration rise of LH seems to be regulated differently.

Melatonin reduction by lithium and albinism in quail and hamsters

Melatonin was measured by radioimmunoassay in several genetic strains of Japanese quail. Plasma melatonin ( pm), measured at the nighttime peak, was highest in wild type quail reared on a diurnal lighting schedule; this PM peak was suppressed in continuous light. Albino quail had low melatonin levels, whether reared under diurnal conditions or in continuous light. Ocular melatonin was also suppressed in albinos and in dilute mutants. At midday sampling, melatonin was only half as high in albinos as in wild types. Intraocular pressure (IOP, daytime readings) was uniformly low in diurnal birds and was elevated in all quail reared under continuous light. Thus in pigmented birds, a high melatonin level was associated with high IOP, but in albinos displaying high IOP, ocular melatonin was not elevated. Lithium chloride, mixed in the feed, brought about a pronounced reduction in plasma, pineal, and ocular melatonin, in wild-type quail reared on a diurnal schedule. This confirms earlier findings in lithium-fed rats. Golden hamsters displayed a characteristic diurnal cycle of pineal melatonin, with a sharp middark peak; in albino hamsters, also kept on a diurnal schedule, this peak occurred at the same time, but albinos had melatonin levels only about one-third as high as those of pigmented animals.

Activity budgets of woolly spider monkeys, or muriquis (Brachyteles arachnoides).

One group of woolly spider monkeys, or muriquis (Brachyteles arachnoides), was observed from June 1983 through July 1984 at Fazenda Montes Claros, Minas Gerais, Brazil. The study subjects spent an average of 49% of their daylight time resting, 29% traveling, and 19% feeding. They shifted their diurnal schedule of activities in response to seasonal changes in temperature and rainfall. The activity budgets of adult males and females were similar. However, a comparison of three adult females in different reproductive conditions revealed that the lactating female spent a greater proportion of time feeding than did both the pregnant and nonreproductive females. Intraspecific differences in group size and diet appear to be important to understanding differences in the activity budgets of Brachyteles. Differences between locomotion patterns of woolly spider monkeys and sympatric howler monkeys may explain activity budget differences based on group size and diet.

An Index of Food Limitation in the Field for the Larval Dragonfly Anax junius (Odonata: Aeshnidae)

The fecal pellet mass of larval Anax junius of a given size is closely correlated with food intake. The fecal pellet mass under ad libitum feeding can be predicted from a knowledge of larval size, and the accuracy of the predictions is not sensitive to wide variation in the diurnal schedule of feeding, water temperature between 15 and 25°, and dietary composition. Comparisons of masses of fecal pellets produced by field collected larvae with predicted masses for ad libitum feeding should, therefore, be a measure of the degree of food limitation in the field.

Correlation of diurnal changes in hormones with sexual behavior and age in male rhesus macaques

—We designed this study to determine whether the sexual behavior of male monkeys changes on a diurnal schedule that coincides with changes in the levels of hormones such as luteinizing hormone (LH), testosterone, estradiol, and cortisol, and whether these differences vary with age. Old (n=8) and young (n=8) males were bled and given sexual behavior tests eight times at 0900 and eight times at 2100. The old and young males did not differ in mean serum levels of testosterone, estradiol, cortisol, or LH. Testosterone and LH levels were lower at 0900 than at 2100 (p<0.01), and estradiol and cortisol levels were higher at 0900 than at 2100 (p<0.01). The young males had higher percentages of tests with erections, mounts, intromissions, and ejaculations than the old males (p<0.01). The rates contacting, mounting, and intromitting were higher at 0900 than at 2100 (p<0.05). We failed to confirm previously obtained correlations between hormone levels and sexual performance. This failure led us to conclude that any significant correlation between sexual behavior and hormone levels must be regarded as tentative unless repeated in successive independent studies.

Endocrine correlates of infertility in male primates

The endocrine correlates of infertility in primates are not well understood. On the basis of the levels of gonadotropins in the systemic circulation, infertile men can be classified as eugonadotropic, hypergonadotropic, or hypogonadotropic. Men who have “normal” gonadotropin levels and oligospermia are sometimes treated with one of the following: testosterone, human menopausal gonadotropin, or clomiphene citrate. Fertility is improved in a small percentage of the patients thus treated. In syndromes such as Klinefelter's gonadotropins are elevated in the systemic circulation, testosterone levels are low, and there are varying degrees of seminferous tubule failure. The hypogonadotropic syndromes seem to be an extension of the prepubertal state. Infertility in men can be classified according to the amount of testicular damage estimated by testicular biopsy. Generally speaking, the greater the degree of damage to the seminiferous tubule, the greater the quantities of gonadotropin, especially FSH, that can be found in the systemic circulation. In nonhuman primates many behavioral defects contribute to infertility. Testosterone in male rhesus monkeys is secreted on a diurnal schedule. Although the significance of this pattern is not known, differences in the diurnal rhythms of breeders and nonbreeders have been detected. Measurements of gonadal steroids in the systemic serum of fertile and infertile male gorillas did not reveal differences in steroid concentrations that could be correlated with infertility. The possibility remains that some type of infertility in great apes may be related to immunologic factors.

Effect of dehydration on hypothalamic control of evaporation in the cat.

1. Cats were surgically prepared with intracranial thermodes for heating of the hypothalamic thermosensitive area or with venous cannulae for measurement of blood volume and plasma osmolality. They were kept in an environmental chamber in which the ambient temperature was cycled between 25 and 38 degrees C on an 18:6 hr diurnal schedule. 2. Measurements of blood volume and plasma osmolality and of the evaporative response to hypothalamic heating were made during the 38 degrees C phase of the diurnal temperature cycle in animals when they were hydrated ad lib and in the same animals after 72--96 hr of water deprivation. 3. Water deprivation produced a loss of 10% of the body weight, a significant rise in plasma osmolality and a significant fall in blood volume. 4. Hypothalamic heating in hydrated animals generated a highly significant, positive, linear relationship between hypothalamic temperature and evaporative heat loss in every case. 5. In dehydrated animals, the evaporative response to hypothalamic heating was reduced. Rates of evaporation at a given hypothalamic temperature were lower and the slopes of the lines relating evaporative heat loss to hypothalamic temperature were significantly reduced. 6. It is concluded that dehydration reduces the thermal responsiveness of central neural structures controlling evaporation in the cat.

Ultradian luteinizing hormone and testosterone rhythms in the adult male monkey, Macaca fascicularis.

Using the RIA for measuring serum testosterone (T) levels and the mouse interstitial cell bioassay for measuring monkey LH, we studied the secretory dynamics of these hormones in the adult male monkey. Eight sexually mature monkeys of the species Macaca fascicularis were sedated and blood was sampled under various protocols over 24 h. All experiments were conducted between February and June. A pronounced diurnal rhythm in the serum concentration of T was revealed by measurements from individual means summed over 4-h morning and evening intervals (0700–1100 and 1900–2300 h) in eight animals. The mean evening T levels (12.2 ± 0.8 ng/ml) were significantly greater than the morning values (9.1 ± 0.8 ng/ml; P < 0.02). Measurements at 20-min intervals over the 4-h periods revealed discrete pulses of T and LH secretion occurring during the morning (0700–1100 h) and evening (1900–2300 h). Analysis of T pulse frequencies and amplitudes between morning and evening showed a significantly higher frequency of pulses occurring in the evening (1.5 ± 0.27 pulses/4 h) than in the morning (0.25 ± 0.27/4 h); pulse amplitudes were not different between morning and evening samples. Samplings at 20-min intervals over 24 h showed a similar pattern. A clear relationship was found between episodic LH and T secretion during both day and nighttime sampling intervals; each individual pulse of T began within 20 min after discrete 3- to 10-fold increases in the serum LH concentration. These data show that in the male monkey, the apparent diurnal rhythm of serum T level is due to a diurnal modulation of the frequency of a pronounced ultradian rhythm in the secretion of this hormone; furthermore, these data document a nearly one to one relationship between pulsatile T andLH secretion, and suggest that the central nervous systempituitary axis operates on a diurnal schedule to modulate the frequency of pulsatile LH secretion in this species.

Effect of Nembutal on LH Release in Baboons

Regularly cycling female baboons were selected and maintained under a diurnal light schedule from 0500 to 1900 hr (CST). Beginning three days prior to the expected LH peak, blood was collected daily at 0800 and 1600 hr for 6 days in 5 baboons under light sedation for radioimmunoassay of plasma LH and estrogen. The plasma level of LH increased linearly and reached a peak in the afternoon of the second day. The peak in plasma estrogen appeared prior to the LH peak. In order to examine the critical period of LH surge in baboons, nembutal was injected daily at 1300 hr beginning a few days prior to expected LH relase. Initial dose of nembutal was 35 mg/kg body weight, but a supplementary dose was later required for a full 5 hours of anesthesia. Blood was collected at 1600 hr from 4 baboons during nembutal injections and after cessation of nembutal injections for radioimmunoassay of plasma LH and estrogen. It was found that nembutal injections suppressed LH release in 2 baboons, and caused a delay of LH release in 2 baboons. However, the plasma level of estrogen declined immediately after initiation of nembutal injection and remained lower. The evidence illustrates the nature of the neural components of LH release which became effective in the afternoon during the ovulatory phase. In addition, a linear increase in plasma level of LH, which is due to accumulation of circulating LH, is necessary for induction of ovulation in baboons.

Diurnal Rhythms in Pineal N-Acetyltransferase and Hippocampal Norepinephrine: Effects of Water Deprivation, Blinding and Hypothalamic Lesions

The pineal gland in the rat exhibits a diurnal rhythm in activity of the enzyme serotonin N-acetyltransferase (N-AT) with peak values during the dark period of a diurnal lighting schedule approximately 100-fold those during the light period. After blinding the rhythm becomes free-running. It is abolished by partial hypothalamic deafferentation with a knife cut made caudal to the optic chiasm. Water deprivation for 23 h daily has no effect on the pineal rhythm in either intact, blinded or deafferented animals. In contrast to this, there is a diurnal rhythm in hippocampal formation in norepinephrine content which can be entrained by a water deprivation schedule in both intact and blinded animals. These observations indicate that in the same animals 1 diurnal rhythm may remain entrained to the light-dark cycle while another rhythm is entrained to a secondary synchronizer, the water deprivation schedule.

REPRODUCTIVE PERFORMANCE OF DOMESTIC FOWL MAINTAINED UNDER CONTINUOUS LIGHT.

Summary. When domestic fowl were maintained under constant incandescent illumination from time of hatching, the rate of egg production was similar to that of control birds on a diurnal schedule. Hatchability of fertile eggs produced by such hens was found to be unaffected by lighting treatment of the parents. Fertility was, however, markedly impaired in the males reared under continuous light. Artificial insemination of the same hens with semen from these males completely corrected this low fertility.

Social Behavior of Elk, Cervus Canadensis Nelsoni, in the Jackson Hole Area of Wyoming

The social life of the North American elk, Cervus canadensis nelsoni, was studied in the Jackson Hole Wildlife Park and in the adjoining wilderness territory. The research was sponsored by the New York Zoological Society and covered four summer seasons from 1948-51. The main method of observation was by stalking or by using blinds. It was found that climatic and seasonal factors modified the daily routine of herd-life. Definite patterns of herd structure and movement were found to exist. In contrast to other herd-forming mammals (sheep, cattle, buffalos, horses), the elk had a tendency in case of disturbance to break through a driving force. The segregation of groups by sex, into bull group and cow-nursery groups was shown. The changes in group structure in travel, grazing, crossing obstacles and in flight were described. A diurnal schedule of action for the elk groups showed regularity. Play-activity of elk-calves and their interaction with the herd followed definite patterns. The dominant-subordinate behavior of elk within the cow-herd and within the bull-group manifested little violence but was firmly established. Leadership by mature elk cows existed in the majority of observed situations. Group changes with the approach of the rutting season in August and September led to the gradual dissolving of the bull-elk groups during the velvet-rubbing stage (August), and to the joining of bulls with existing cow-elk groups. The full emergence of the rutting season in September with cold spells providing stimulation for bugling and sex-activity was noted. The behavior of the free-ranging elk of the Jackson Hole herd was observed while the elk were still on the winter-feeding grounds of the Elk Refuge; the formation of sub-groups took place within the Refuge weeks before actual migration. The subgroups sometimes broke into smaller and very small (3 to 5 elk) units, proceeded along the water runs toward higher locations outside of the Refuge. The onset of the calving season changed the group composition, delaying the cows and some of their yearlings. Groups of males and some non-bred females moved on to higher altitudes in the wilderness areas. Relations and interactions of cows and calves and establishment of calf pools on a cooperative basis were noted. Female bugling, defense reactions and the displacement of yearlings was shown. The elk groups under stress of disturbances (highway with traffic) and natural obstacles (river crossings) showed integrated action. Male groups arrived early on high summer ranges, still covered with snow. Gradual arrival of nursery groups through main routes of migration. Adaptation to the cold climate and abundant pasture changed schedule of daily activity completely. Besides pasturing, the elk spent much time and energy in play, bathing and wallowing. Vocal communications were frequent and conspicuous. Bugling of males while still in velvet was commonly heard. Group formation was found to be loosely defined. Aggregations of several hundred elk were frequently seen but also medium and small elk bands were found. Flight distance was lowest ever encountered. Elk were bold, not nervous and in prime condition by midsummer. Contrast to normal elk behavior on summer ranges was shown by groups of elk on poor habitat. Their schedule of activity from dusk to dawn was interrupted by a period of rest and rumination during the hot midday. Poor grazing caused the animals to look shaggy and to show nervous disposition indicated by an extremely high object-flight-distance. No playful activity was detected. Grazing and fly-fighting occupied a large proportion of their time. Group organization was constant with leadership by mature females.