Diurnal Activity Patterns Research Articles

Spatial and temporal coexistence of medium-sized felines and their potential preys in Sierra Madre del Sur of Guerrero, México

Two species of similar size and trophic niche could not coexist in the same space and time unless the resources are diverse, abundant, and can be shared. In the Sierra Madre del Sur, Guerrero, Mexico, three felines of similar size coexist, Herpailurus yagouaroundi, Leopardus pardalis, and Leopardus wiedii. The objective of this research was to identify the spatiotemporal patterns that allow the coexistence of three felines and their potential preys, as well as to evaluate how the presence of humans and livestock influence their use of space and time. We hypothesized that the three felines coexist due to a differential use of time and space. Therefore, low or moderate overlap is expected, as well as a positive relationship with prey richness but negative regarding the presence of humans and livestock. Between 2009 and 2019, information was obtained on how the three feline species and their potential prey use time and space in eight landscapes with wide environmental variation using camera trapping. With a total sampling effort of 27,014 days/trap in 1,170 km2, 362 independent records of felids and 2,287 of 12 potential preys were obtained. Overlap in daily activity patterns (Δ) was estimated, and spatial co-occurrence was calculated using epsilon (Ɛ) values. Our results show that jaguarundi displayed a diurnal activity pattern and had an overlap of Δ = 0.22 with ocelot and Δ = 0.26 with margay; ocelot and margay were nocturnal with an activity overlap of Δ = 0.87. The spatial co-occurrence between the three felid species was positive: Ɛ = 2.61 between ocelot and margay, Ɛ = 3.22 between ocelot and jaguarundi; and Ɛ = 6 between jaguarundi and margay. The temporal overlap and spatial co-occurrence among felines showed a similar use of resources, and their distribution coincide with the one of some of their potential preys, may be related to predation strategies. Temporal overlap and spatial co-occurrence alone do not limit the coexistence of species; but the environmental differences of the landscapes do influence the variation and temporal dynamics of the felines studied in the Sierra Madre del Sur de Guerrero.

Population dynamics and wintering behavior of the black–headed gull Chroicocephalus ridibundus at El Mellah lagoon (Northeastern Algeria)

Abstract The population dynamics and behavior of the black-headed gull of an Algerian coastal wetland, El Mellah lagoon (Lake Mellah), were studied during three consecutive wintering seasons (2018–2021). Maximum numbers of the species were counted in December and January depending on the year. A peak of 536 individuals was recorded in the first half of December 2018, another of 538 individuals in the second half of December 2019, and a final peak of 636 birds in the first half of January 2021. Diurnal activity patterns showed that feeding was the primary behavior, with a mean of 24% for the three seasons. It was followed by sleeping (21%), swimming (19%), preening (18%), and flight (17%). Black-headed gulls appeared to be more active in the morning than at other times of the day. This study attempts to provide recent and unpublished data on the wintering and behavior of the black-headed gull, which remains poorly documented in North Africa and particularly in Algeria, and highlights the patterns of wetland use by these species, which could help to evaluate the importance of certain areas and develop management plans specific to coastal habitats and their avifaunal diversity.

Activity patterns of the Yellow-throated marten Martes flavigula in the Far East of Russia revealed by camera traps

Abstract The Yellow-throated marten Martes flavigula is one of the least studied species within the genus Martes and there is contradictory information regarding its daily activity, spanning from diurnal to nocturnal or cathemeral. Our long-term studies of the daily and seasonal activity of the Yellow-throated marten were carried out in five protected areas of Primorsky Krai (Russian Far East) using a large-scale network of camera traps from 2010 to 2021. The aim of the study was to find out the pattern of daily activity of the species, its changes over the seasons and in different territories of the region. We found that the Yellow-throated marten had a pronounced diurnal activity pattern, including one or two detection peaks per day. The species is less active at dusk and almost inactive at night in this part of its range. Two clusters with different patterns of marten activity were identified in the protected areas of Primorsky Krai: with one pronounced peak around noon in the continental part with a more severe climate and smoothed activity in coastal areas with milder climatic conditions. Seasonal detection has two peaks in April-May and October, which corresponds to species biological requirements.

Revealing the Mediterranean Monk Seal (Monachus monachus)’s Cave Preference in Gökova Bay on the Southwest Coast of Türkiye

The first cave-monitoring studies to be carried out on the southwest (SW) coast of Türkiye on endangered Mediterranean monk seals using camera traps occurred between 2017 and 2021 in five marine caves within Gökova Bay. The visual data obtained from the monitoring studies were evaluated to reveal the Mediterranean monk seals’ seasonal and diel cave use and identify the individual seals who were using the caves. Moreover, the necessary features and measurements of the identified caves were recorded to determine whether there were any correlations between the determined variables and monthly cave use by the monk seals. The results showed that cave use occurred mainly nocturnally, with the seals showing a diurnal activity pattern in the area. We evaluated 108,280 images/videos in total and identified 18 individuals using five caves in Gökova Bay. Three of these caves provided suitable characteristics for pupping, and two of them were used for pupping. A beta regression model revealed that the monthly cave use ratios varied seasonally, with more use in the fall season. Furthermore, the trends in annual cave use ratios, seasonality, wind speed, size of the wet area, luminance, number of cave-entry paths, and human activity were the best variables with which we could forecast the cave preferences of the seals.

Running overnight and struggling to find sea ice: long-distance movement by an Arctic fox (Vulpes lagopus) from Russia

Given the scale, speed, and complexity of recent changes in the Arctic, our understanding of their multiple implications for Arctic biota is still limited. We detail for the first time in the vast Russian Arctic the long-distance movement of an Arctic fox ( Vulpes lagopus (Linnaeus, 1758)) tracked with a GPS/iridium collar providing considerably high precision (several meters) and frequency of locations (every 4 h). Revealed diurnal activity patterns of the Arctic fox indicate that it ran greater distances in night hours and shortest in day hours during the most intense movement period. The movement records suggested several attempts to leave the land, as it seemed to encounter open water four times on different parts of Yamal peninsula. The Arctic fox crossed the Ob Bay towards the Gydan peninsula and satellite imagery of discontinuous ice during crossing suggested that it might have stayed on pieces of floating ice. Our observation may support evidence that a reduction in the duration and extent of sea ice could affect the ability of Arctic foxes to cover long distances and thus, in the long term, the connectivity between populations. Similar studies are needed aiming to understand movement ecology of the Arctic foxes in the changing Arctic.

Seasonal variation in the diurnal activity pattern of Eurasian blackbirds (Turdus merula) in the forest

Camera traps are increasingly used to estimate the density of animals as well as their activity patterns. As camera traps allow monitoring of animals over long periods of time without disturbance, they are especially useful to observe changes in diurnal activity patterns over time. In ornithology, camera trapping is still in its infancy. To our knowledge, no study has yet investigated the activity pattern of a songbird over the full annual cycle. We used camera traps in the Rammert, a small mountainous forest area near Rottenburg in Southwest Germany to monitor the diurnal activity pattern of forest-dwelling Eurasian blackbirds (Turdus merula). As the activity level of animals is known to be affected by day light, we used double-anchoring transformation of day times to account for the variation in sunrise and sunset across the different seasons. By generating activity models, we investigated the pattern of blackbird activity during the four seasons of the year and compared the patterns of male and female birds, respectively. A significant difference between a unimodal activity pattern in spring and a bimodal pattern for the rest of the year was found which might be related to breeding and territorial behaviour in spring. Moreover, we observed that the activity pattern of males and females overlapped greatly but still showed some variation in the number and timing of density peaks.

Human disturbances and the daytime activity of sympatric otters along equatorial Amazonian rivers.

Previous studies suggest coexistence between sympatric neotropical (Lontra longicaudis) and giant otters (Pteronura brasiliensis) maybe facilitated by temporal and spatial differences in activity. Yet, to date there has been no systematic evaluation of activity of these species in sympatry. Here we use extensive multi-year field data to compare temporal and spatial patterns in the diurnal activity of sympatric giant and neotropical otters to answer three questions: Do temporal patterns in daytime river use change in relation to seasonal river levels (low, rising, high and declining river levels), do they change due to human disturbances (boats and fishing nets) and do patterns in neotropical otter activity change due to the presence of the larger sized giant otter? Direct observations of both species were recorded using standardized boat surveys along 218 km of rivers over 53 months during nine years (2011-2013 and 2015-2020). Complementary techniques (Generalized Additive Models, Kernel density estimates and non-parametric tests,) were used to compare diurnal activity patterns along rivers subdivided into 41 river reaches. The presence of giant otters decreased threefold from 67% of the least disturbed reaches (few boats no fishing nets) to 18% of the most disturbed reaches with many boats and fishing nets. In contrast neotropical otter presence nearly doubled from 44% of the least disturbed to 73% of the most disturbed reaches with fewest giant otter detections. Both species were observed across all daytime hours but were observed rarely on the same day. There was no evidence to suggest simultaneous use of the same reach. When species were detected on the same day, they were separated spatially (median distance between species 12.5 km) and temporally (median time difference 3.0 hours). There was little change in activity of either species among seasons. Giant otters were less active in river reaches with fishing nets and boat use, whereas neotropical otter activity did not appear to be strongly affected by these activities. Our findings support evidence that diurnal activity in both otter species is flexible, with daytime activity changing due to human disturbances in the case of giant otters.

Association of Time-of-Day Physical Activity With Incident Cardiovascular Disease: The UK Biobank Study.

Early morning is characterized by an increased risk of cardiovascular events, a sudden rise in blood pressure, impaired endothelial function, and exacerbated hemodynamic changes during physical activity. The study aims to examine whether the time of day of physical activity is associated with incident cardiovascular disease (CVD). We prospectively analyzed 83,053 participants in the UK Biobank with objectively measured physical activity and initially free of CVD. Based on the diurnal patterns of physical activity, participants were categorized into 4 groups: early morning (n = 15,908), late morning (n = 22,371), midday (n = 24,764), and evening (n = 20,010). Incident CVD was defined as the first diagnosis of coronary heart disease or stroke. During 197.4million person-years of follow-up, we identified 3454 CVD cases. After adjusting for the overall acceleration average, the hazard ratios and 95% confidence intervals were 0.95 (0.86-1.07) for late morning, 1.15 (1.03-1.27) for midday, and 1.03 (0.92-1.15) for evening, as compared with the early morning group. In the joint analyses, higher levels of physical activity were associated with a lower risk of incident CVD in a similar manner across the early morning, late morning, and evening groups. However, the beneficial association was attenuated in the midday group. In conclusion, early morning, late morning, and evening are all favorable times of day to engage in physical activity for the primary prevention of CVD, while midday physical activity is associated with an increased risk of CVD compared with early morning physical activity after controlling for the levels of physical activity.

Camera Traps Uncover the Behavioral Ecology of an Endemic, Cryptic Monkey Species in the Congo Basin.

Guenons are the most diverse clade of African primates, and many species living within the core of the Congo Basin rainforest are still understudied. The recently described guenon species, Cercopithecus lomamiensis, known as lesula, is a cryptic, semi-terrestrial species endemic to the central Congo Basin in the Democratic Republic of the Congo. The recent IUCN Red List Assessment recognizes lesula's risk of extinction in the wild as Vulnerable. The objective of our study was to use camera traps to expand knowledge on the behavioral ecology of lesula. We conducted three systematic, terrestrial camera trap (CT) surveys within Lomami National Park and buffer zone (Okulu: 2013; Losekola: 2014; E15: 2015). We accumulated 598 independent events of lesula over 5960 CT days from 92 CTs. Typical of Cercopithecus species, camera trap videos reveal that lesula has a diurnal activity pattern, birth seasonality, a group size of up to 32 individuals, and social organization with female philopatry and male dispersal. Results also suggest that lesula are highly terrestrial, distinguishing them from other Cercopithecus species, which are mostly arboreal. Our study provides new information about the behavioral ecology of this little-studied primate, generating species-specific knowledge of a threatened species for successful conservation planning.

Diet composition and diurnal activity patterns of gelada baboon (Theropithecus gelada)

AbstractGelada baboons (Theropithecus gelada) are the only surviving species of the genus Theropithecus and endemic to the highlands of Ethiopia. The present study deals with feeding ecology and diurnal activity patterns of gelada (T. gelada) in Wof‐Washa Forest, central Ethiopia. It was conducted from September 2016 to August 2017. Focal sampling technique for 10 min observation was employed to study the feeding ecology. Type of plant species consumed and parts eaten by gelada were recorded using binoculars during dry and wet seasons. On the other hand, data on diurnal activity patterns were collected using scan sampling technique. The activity patterns of bands under study were quantified by scanning at every 15‐min interval from 06:00 to 18:00 h. A total of 11 plant species that belong to 10 families were foraged by gelada during the wet and dry seasons. Grass was the main food source for geladas that contributed about 81% and 68% of their diet during the wet and dry seasons, respectively, while Thymus schimperi was the least consumed plant species during both wet (0.5%) and dry (1%) seasons. Grass blades were the most preferable food items by almost all age and sex categories. Daily activities of gelada were mainly dominated by feeding during both seasons. Geladas spent 58% of their time on foraging activity during the wet season and 67.2% of their time spent during the dry season. Geladas mainly depend on grasses for their diet in the study area. Therefore, to implement successful management and conservation of the species, the area needs to be properly protected.

PyMouseTracks: flexible computer vision and RFID based system for multiple mouse tracking and behavioral assessment.

PyMouseTracks (PMT) is a scalable and customizable computer vision and RFID-based system for multiple rodent tracking and behavior assessment that can be set up within minutes in any user-defined arena at minimal cost. PMT is composed of the online Raspberry Pi-based video and RFID acquisition with subsequent offline analysis tools. The system is capable of tracking up to 6 mice in experiments ranging from minutes to days. PMT maintained a minimum of 88% detections tracked with an overall accuracy >85% when compared to manual validation of videos containing 1-4 mice in a modified home-cage. As expected, chronic recording in home-cage revealed diurnal activity patterns. In open-field, it was observed that novel non-cagemate mouse pairs exhibit more similarity in travel trajectory patterns than cagemate pairs over a 10-minute period. Therefore, shared features within travel trajectories between animals may be a measure of sociability that has not been previously reported. Moreover, PMT can interface with open-source packages such as Deeplabcut and Traja for pose estimation and travel trajectory analysis, respectively. In combination with Traja, PMT resolved motor deficits exhibited in stroke animals. Overall, we present an affordable, open-sourced, and customizable/scalable mouse behavior recording and analysis system.Statement of SignificanceAn affordable, customizable, and easy-to-use open-source rodent tracking system is described. Most current tools, commercial or otherwise, can only be fully automated to track multiple animals in a single defined environment and are not easily setup within custom arenas or cages. Moreover, many tools require users to have extensive hardware and software knowledge. In contrast, PMT is easy to install and can be adapted to track rodents of any coat color in any user-defined environment with few restrictions allowing quantification of behavior in multiple animals simultaneously.

Diurnal Step Count Patterns in Progressive Multiple Sclerosis (P3-3.011)

<h3>Objective:</h3> Determine the relationship of diurnal step count patterns with disability in progressive multiple sclerosis (MS). <h3>Background:</h3> Worsening Expanded Disability Status Scale (EDSS) scores and longer Timed 25-Foot Walk (T25FW) times generally correspond to increased MS disability and correlate with lower daily physical activity. Patterns of diurnal physical activity and MS disability progression are understudied. <h3>Design/Methods:</h3> Participants (n=577) in the SPI2 study of MD1003 (high dose biotin) in progressive MS underwent EDSS and T25FW every three months with up to 27 months of follow up. A Fitbit flex (or flex2) continuously monitored step counts per minute. Recorded data was analyzed using the function-on-scalar regression technique where EDSS, T25FW and other patient demographics were used to predict per-patient diurnal step counts. <h3>Results:</h3> From 12pm to 8pm, EDSS (mean R2 = 0.36±0.02) outperformed T25FW (mean R2 = 0.26±0.02) in predicting mean diurnal step count curves per patient after adjusting for sex, age, and BMI. Including EDSS and T25FW increased mean R2 to 0.39±0.02. Men took 5.2% more steps than women from 12am to 7am on average, while women took 5.1% more steps than men from 10:30am to 1:30pm and 4.3% more from 7:30pm to 10pm on average (all p&lt;0.001). The impact of age was strongest from 3pm to 10pm, where each year of age corresponded to 0.44% fewer steps (p&lt;0.0001). From 10am to 11pm, every one-point increase in BMI translated to 1.3% fewer steps (p&lt;0.0001). Mean diurnal step count had midday troughs in summer, evening troughs in winter, and morning peaks in spring (all p&lt;0.001). <h3>Conclusions:</h3> The association between lower physical activity and disability metrics is not uniform throughout the day, and changes with the seasons. These results highlight the need for consistency in timing of clinical evaluation in research, and provide important insight into specific times of day that may be preferable for effective rehabilitation interventions. <b>Disclosure:</b> Mr. Navani has received personal compensation for serving as an employee of Datavant. Dr. Block has nothing to disclose. The institution of Dr. Cree has received personal compensation in the range of $5,000-$9,999 for serving as a Consultant for Atara. The institution of Dr. Cree has received personal compensation in the range of $5,000-$9,999 for serving as a Consultant for Biogen. The institution of Dr. Cree has received personal compensation in the range of $10,000-$49,999 for serving as a Consultant for EMD Serono. The institution of Dr. Cree has received personal compensation in the range of $10,000-$49,999 for serving as a Consultant for Novartis. The institution of Dr. Cree has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Sanofi. The institution of Dr. Cree has received personal compensation in the range of $5,000-$9,999 for serving as a Consultant for TG Therapeutics. The institution of Dr. Cree has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Autobahn. The institution of Dr. Cree has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Avotres. The institution of Dr. Cree has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Alexion. Dr. Cree has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Gossamer Bio. Dr. Cree has received personal compensation in the range of $5,000-$9,999 for serving as a Consultant for Horizon. Dr. Cree has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Neuron23. Dr. Cree has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Boston Pharma. Dr. Cree has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Hexal/Sandoz. Dr. Cree has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Siemens. Dr. Cree has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Therini. Dr. Cree has received personal compensation in the range of $500-$4,999 for serving on a Scientific Advisory or Data Safety Monitoring board for Immunic AG. The institution of Dr. Cree has received research support from Genentech. Dr. Cree has received publishing royalties from a publication relating to health care. Prof. Abbasi-Asl has received research support from NIH. Prof. Abbasi-Asl has received research support from Weill Neurohub.

Temporal and spatial distribution of dorcas and slender‐horned gazelles in a Saharan habitat

AbstractSaharan ungulates have suffered from poaching across their range leading to population declines. Low abundance and habitat inaccessibility have limited the availability of empirical data on desert ungulate ecology in the wild. Our objective was to evaluate temporal and spatial distribution, and home‐range sizes of wild dorcas gazelles (Gazella dorcas) and slender‐horned gazelles (Gazella leptoceros) under natural conditions using observations from 14,398 camera‐days collected between April 2019 and October 2021 in the 7,700‐ha fenced area of Jbil National Park (Jbil NP), Tunisia. We individually identified gazelles in Jbil NP using unique horn morphology. Both gazelle species exhibited nocturnal activity patterns in summer, but diurnal activity patterns dominated in winter. We also detected both species more frequently in the plains than in mountains. Water presence was influential in determining distribution only for dorcas gazelles. Minimum convex polygons (MCPs) were 2,062 ha for both the male and female of the most frequently detected dorcas gazelle pair and 1,527 ha for another solitary male. For slender‐horned gazelles, MCPs were 2,280 ha and 2,041 ha, respectively, for a male and a female detected in Jbil NP. The decline and rarity of gazelles in the Sahara Desert have limited the sample size of our observed populations. Our study provides hitherto unknown data on wild populations of rapidly declining gazelle species and contributes to ongoing conservation efforts.

Population size and diurnal activity patterns of Bohor reedbuck (Redunca redunca Pallas, 1767) in the compound of Alage Agricultural College, Central Rift Valley of Ethiopia

Abstract Bohor reedbuck is a medium-sized, even-toed ungulate species endemic to Africa. Its population is gradually declining, and an estimation of Meta populations is required to determine its current population status and as an input for conservation action. To this end, this study aimed to investigate this species’ population size and diurnal activity patterns in the compound of Alage Agricultural College, Central rift valley of Ethiopia. A total count was conducted to determine the population size of Bohor reedbuck by dividing the study area into different blocks. Continuous focal animal observations were used to collect data on activity patterns by recording group activities with five minutes intervals. The results revealed that the mean population size of Bohor reedbuck counted during the study period was (SE) with a density of 1.74 per km2. Females formed the dominant group in the population. From the mean total population size of Bohor reedbucks, 47.42% were adults. The mean group size of Bohor reedbuck was (SE). Feeding (, 45.81%) was the dominant mean diurnal activity pattern of Bohor reedbuck, followed by Resting (, 31.91%), whereas grooming (, 3.51%) was the least performed activity. There was a significant difference between the diurnal activities performed by Bohor reedbuck (). The studied compound is an important refuge for this species, and minimum management interference can increase the population size of Bohor reedbuck in the area.

Widespread psychoactive pollutant augments daytime restfulness and disrupts diurnal activity rhythms in fish

Pharmaceutical pollution is a major driver of global change, with the capacity to alter key behavioural and physiological traits in exposed animals. Antidepressants are among the most commonly detected pharmaceuticals in the environment. Despite well-documented pharmacological effects of antidepressants on sleep in humans and other vertebrates, very little is known about their ecologically relevant impacts as pollutants on non-target wildlife. Accordingly, we investigated the effects of acute 3-day exposure of eastern mosquitofish (Gambusia holbrooki) to field-realistic levels (nominal concentrations: 30 and 300 ng/L) of the widespread psychoactive pollutant, fluoxetine, on diurnal activity patterns and restfulness, as indicators of disruptions to sleep. We show that exposure to fluoxetine disrupted diel activity patterns, which was driven by augmentation of daytime inactivity. Specifically, unexposed control fish were markedly diurnal, swimming farther during the day and exhibiting longer periods and more bouts of inactivity at night. However, in fluoxetine-exposed fish, this natural diel rhythm was eroded, with no differences in activity or restfulness observed between the day and night. As a misalignment in the circadian rhythm has been shown to adversely affect fecundity and lifespan in animals, our findings reveal a potentially serious threat to the survival and reproductive success of pollutant-exposed wildlife.

Temporal Dissociation Between Activity and Body Temperature Rhythms of a Subterranean Rodent (Ctenomys famosus) in Field Enclosures.

Several wild rodents, such as the subterranean tuco-tucos (Ctenomys famosus), switch their time of activity from diurnal to nocturnal when they are transferred from field to the laboratory. Nevertheless, in most studies, different methods to measure activity in each of these conditions were used, which raised the question of whether the detected change in activity timing could be an artifact. Because locomotor activity and body temperature (Tb) rhythms in rodents are tightly synchronized and because abdominal Tb loggers can provide continuous measurements across field and laboratory, we monitored Tb as a proxy of activity in tuco-tucos transferred from a semi-field enclosure to constant lab conditions. In the first stage of this study ("Tb-only group," 2012-2016), we verified high incidence (55%, n = 20) of arrhythmicity, with no consistent diurnal Tb rhythms in tuco-tucos maintained under semi-field conditions. Because these results were discrepant from subsequent findings using miniature accelerometers (portable activity loggers), which showed diurnal activity patterns in natural conditions (n = 10, "Activity-only group," 2016-2017), we also investigated, in the present study, whether the tight association between activity and Tb would be sustained outside the lab. To verify this, we measured activity and Tb simultaneously across laboratory and semi-field deploying both accelerometers and Tb loggers to each animal. These measurements (n = 11, "Tb + activity group," 2019-2022) confirmed diurnality of locomotor activity and revealed an unexpected loosening of the temporal association between Tb and activity rhythms in the field enclosures, which is otherwise robustly tight in the laboratory.

Artificial diet alters activity and rest patterns in the olive fruit fly.

Olive fruit flies, Bactrocera oleae (Diptera: Tephritidae) reared in the laboratory on an artificial diet are essential for the genetic control techniques against this pest. However, the colony's laboratory adaptation can affect the quality of the reared flies. We used the Locomotor Activity Monitor to track the activity and rest patterns of adult olive fruit flies reared as immatures in olives (F2-F3 generation) and in artificial diet (>300 generations). Counts of beam breaks caused by the adult fly activity were used as an estimation of its locomotor activity levels during the light and dark period. Bouts of inactivity with duration longer than five minutes were considered a rest episode. Locomotor activity and rest parameters were found to be dependent on sex, mating status and rearing history. In virgin flies reared on olives, males were more active than females and increased their locomotor activity towards the end of the light period. Mating decreased the locomotor activity levels of males, but not of female olive-reared flies. Laboratory flies reared on artificial diet had lower locomotor activity levels during the light period and more rest episodes of shorter duration during the dark period compared to flies reared on olives. We describe the diurnal locomotor activity patterns of B. oleae adults reared on olive fruit and on artificial diet. We discuss how locomotor activity and rest pattern differences may affect the laboratory flies' ability to compete with wild males in the field.

Disturbed circadian rhythm of locomotor activity of pullets is related to feather pecking in laying hens

Various aspects of activity, such as spontaneous activity, explorative activity, activity in open-field tests, and hyperactivity syndrome have been explored as causal factors of feather pecking in laying hens, with no clear results. In all previous studies, mean values of activity over different time intervals were used as criteria. Incidental observation of alternated oviposition time in lines selected for high (HFP) and low feather pecking (LFP), supported by a recent study which showed differentially expressed genes related to the circadian clock in the same lines, led to the hypothesis that feather pecking may be related to a disturbed diurnal activity rhythm. Hence activity recordings of a previous generation of these lines have been reanalyzed. Data sets of a total of 682 pullets of 3 subsequent hatches of HFP, LFP, and an unselected control line (CONTR) were used. Locomotor activity was recorded in pullets housed in groups of mixed lines in a deep litter pen on 7 consecutive 13-h light phases, using a radio-frequency identification antenna system. The number of approaches to the antenna system was recorded as a measure of locomotor activity and analyzed using a generalized linear mixed model including hatch, line, time of day and the interactions of hatch×time of day and line×time of day as fixed effects. Significant effects were found for time and the interaction line×time of day but not for line. All lines showed a bimodal pattern of diurnal activity. The peak activity of the HFP in the morning was lower than that of the LFP and CONTR. In the afternoon peak all lines differed with the highest mean in the LFP followed by CONTR and HFP. The present results provide support for the hypothesis that a disturbed circadian clock plays a role in the development of feather pecking.

Habitat use and diurnal activity budget of blue bulls (Boselaphus tragocamelus) in the Lumbini Heritage Site, Nepal

Blue bulls (Boselaphus tragocamelus) in Nepal are found near human settlements, crop fields and forest patches of lowland Terai and their management is becoming challenging due to conflicts with locals. This study explored habitat use and diurnal activity pattern of blue bulls at the Lumbini Heritage Site (LHS), one of the UNESCO World Heritage Sites from Nepal between 29 February and 31 March 2022. The habitat availability was quantified from classified land use land cover data of 10 m resolution and habitat use of the blue bulls was studied by direct observation. Activities of the blue bulls were recorded by the focal animal sampling method to determine the diurnal time budget for three observational phases 7:00–10:30 AM, 10:30–2:00 PM, and 2:00–5:30 PM; morning, afternoon and late-afternoon, respectively. The behavioral states recorded were grazing, locomotion, resting, alert and other activities (running, fighting, etc.). A total of 73 individuals of blue bulls were recorded along the 20 line transects each of 200–300 m in length. The majority of the blue bull individuals (52.05%) were observed in grassland that occupied only 7.14% of the LHS while lesser were found in dense forests (44.44% of the LHS) and agricultural land. Blue bulls spent the majority of their diurnal time on feeding followed by resting and locomotion. Feeding peaked during the morning and late-afternoon observational phases when the temperature was low whereas resting was the major activity in the afternoon. Because the grasslands are the most used habitats by blue bulls in the LHS, especially for feeding, we emphasize the proper management of the grasslands.

Responses in thermal tolerance and daily activity rhythm to urban stress in Drosophila suzukii.

Cities experience changes in abiotic factors, such as warming, increases in noise and light. These changes can lead to phenotypic changes. Several studies have revealed that altered environments change phenotypes in plants and animals in cities. However, limited studies have isolated evolutionary from nongenetic changes. Here, we analyzed the evolution of thermal tolerance and diurnal activity patterns in the urban population of the fruit pest, Drosophila suzukii. Urban and rural isofemale lines were reared under constant conditions. We compared the lower and upper thermal limits (CTmin and CTmax, respectively), and effects of temperature exposure on the thermal limits of urban and rural populations. Common garden experiments showed that urban populations exhibit a lower CTmin than rural populations, suggesting genetic difference in CTmin among populations. On the other hand, the difference in CTmax between urban and rural populations was not significant. Exposure to cold temperature did not affect CTmin in both urban and rural populations. In contrast, exposure to hot temperature increased CTmax especially in urban population, suggesting that urban populations evolved in response to urban heat. We also investigated the daily activity patterns of urban and rural populations and the effect of lifelong artificial light at night on daily activity. We found that night-time light (dim light) reduced the total amount of activity compared to dark night condition. In addition, dim light at night altered the daily rhythm of activity and increased the activity rate at night. The effect of night light on total activity was less in urban than that in rural populations, suggesting that populations in cities evolved to mitigate decreased activity under night light. Our results showed that environmental temperature and artificial light at night evolutionarily and plastically influence ecologically important traits, such as temperature tolerance and diurnal activity.