scholarly journals Day and night in the subterranean: measuring daily activity patterns of subterranean rodents (Ctenomys aff. knighti) using bio-logging

2019 ◽  
Vol 7 (1) ◽  
Author(s):  
Milene G Jannetti ◽  
C Loren Buck ◽  
Veronica S Valentinuzzi ◽  
Gisele A Oda

Abstract While most studies of the impacts of climate change have investigated shifts in the spatial distribution of organisms, temporal shifts in the time of activity is another important adjustment made by animals in a changing world. Due to the importance of light and temperature cycles in shaping activity patterns, studies of activity patterns of organisms that inhabit extreme environments with respect to the 24-hour cyclicity of Earth have the potential to provide important insights into the interrelationships among abiotic variables, behaviour and physiology. Our previous laboratory studies with Argentinean tuco-tucos from the Monte desert (Ctenomys aff. knighti) show that these subterranean rodents display circadian activity/rest rhythms that can be synchronized by artificial light/dark cycles. Direct observations indicate that tuco-tucos emerge mainly for foraging and for removal of soil from their burrows. Here we used bio-logging devices for individual, long-term recording of daily activity/rest (accelerometry) and time on surface (light-loggers) of six tuco-tucos maintained in outdoor semi-natural enclosures. Environmental variables were measured simultaneously. Activity bouts were detected both during day and night but 77% of the highest values happened during the daytime and 47% of them coincided with time on surface. Statistical analyses indicate time of day and temperature as the main environmental factors modulating time on surface. In this context, the total duration that these subterranean animals spent on surface was high during the winter, averaging 3 h per day and time on surface occurred when underground temperature was lowest. Finally, transport of these animals to the indoor laboratory and subsequent assessment of their activity rhythms under constant darkness revealed a switch in the timing of activity. Plasticity of activity timing is not uncommon among desert rodents and may be adaptive in changing environments, such as the desert where this species lives.

1985 ◽  
Vol 63 (1) ◽  
pp. 86-91 ◽  
Author(s):  
V. P. J. Gannon ◽  
D. M. Secoy

The seasonal and daily activity patterns of a Saskatchewan population of Crotalus viridus viridis is presented. Snakes emerged from hibernation in late April and migrated into the surrounding river valley and upland regions in early May. Adult migration preceded that of immature age-classes. Several gravid females occupied a rookery near the hibernaculum during the summer months and remained there until parturition. Females did not occupy this site in successive years and may have a biennial or greater reproductive cycle. Snakes returned to the hibernaculum in early September and remained active until early October. The behaviour of snakes in a field enclosure in response to time of day and body temperature (Tb) was recorded during the spring, summer, and fall. Significant differences in the Tb values of sunning, movement, and shading behaviours were noted. Gravid females were significantly more active in all seasons. However, no significant difference in mean Tb was found between males and females in the field, enclosure study, or laboratory thermal gradient. The observed greater level of activity may reflect the high energy demands of gravid females.


2021 ◽  
Vol 8 ◽  
Author(s):  
Elizabeth M. Morris ◽  
Susanna E. Kitts-Morgan ◽  
Dawn M. Spangler ◽  
Jessica Gebert ◽  
Eric S. Vanzant ◽  
...  

Growing public interest in the use of cannabidiol (CBD) for companion animals has amplified the need to elucidate potential impacts. The purpose of this investigation was to determine the influence of CBD on the daily activity of adult dogs. Twenty-four dogs (18.0 ± 3.4 kg, 9 months−4 years old) of various mixed breeds were utilized in a randomized complete block design with treatments targeted at 0 and 2.5 mg (LOW) and at 5.0 mg (HIGH) CBD/kg body weight (BW) per day split between two treats administered after twice-daily exercise (0700–0900 and 1,700–1,900 h). Four hours each day [1,000–1,200 h (a.m.) and 1,330–1,530 h (p.m.)] were designated as times when no people entered the kennels, with 2 h designated as Quiet time and the other 2 h as Music time, when calming music played over speakers. Quiet and Music sessions were randomly allotted to daily a.m. or p.m. times. Activity monitors were fitted to dogs' collars for continuous collection of activity data. Data were collected over a 14-day baseline period to establish the activity patterns and block dogs by activity level (high or low) before randomly assigning dogs within each block to treatments. After 7 days of treatment acclimation, activity data were collected for 14 days. Data were examined for differences using the MIXED procedure in SAS including effects of treatment, day, session (Quiet or Music), time of day (a.m. or p.m.), and accompanying interactions. CBD (LOW and HIGH) did not alter the total daily activity points (P = 0.985) or activity duration (P = 0.882). CBD tended (P = 0.071) to reduce total daily scratching compared with the control. Dogs were more active in p.m. sessions than in a.m. sessions (P < 0.001). During the p.m. session, dogs receiving HIGH tended (P = 0.091) to be less active than the control (CON). During the a.m. and p.m. sessions, CBD reduced scratching compared with CON (P = 0.030). CBD did not affect the activity duration during exercise periods (P = 0.143). These results indicate that, when supplemented with up to 4.5 mg CBD/kg BW/day, CBD does not impact the daily activity of adult dogs, but may exert an antipruritic effect.


2005 ◽  
Vol 32 (2) ◽  
pp. 157 ◽  
Author(s):  
H. Butler ◽  
B. Malone ◽  
N. Clemann

Translocation of snakes is a common practice for managing human–snake conflict in many parts of Australia. The impact of this management on individual snakes is not known. Differences between translocated and non-translocated snakes in terms of their activity patterns and habitat use are likely to indicate an impact on individual snakes from this procedure. We investigated these issues in a suburban parkland close to Melbourne for one of the most familiar of these snakes, the tiger snake (Notechis scutatus). This parkland is frequently used by licenced snake controllers to release snakes that have been removed from nearby private properties at the owner’s request. We used two techniques to assess activity patterns and habitat preferences of resident and translocated snakes: direct observations of tiger snakes that were resident in the park, and radiotelemetry to compare a subset of resident snakes with translocated conspecifics. The size of our transmitters dictated that we only use telemetry for large snakes (≥750 mm snout–vent length), even though the resident population consisted mainly of intermediate-sized females (560–760 mm snout–vent length). Non-telemetred resident snakes were readily observed during spring, but rarely observed in summer and early autumn. Translocated snakes travelled greater distances than resident telemetred snakes, although there was no difference in the frequency of movements. For both groups the degree of cloud cover and maximum daily temperature had a significant influence on daily activity, with snakes being more likely to be active on relatively cool, sunny days. Relative humidity, wind speed and rainfall did not exert a significant influence on activity. Snakes exhibited bimodal peaks in daily activity, avoiding the hottest part of the day. Both resident and translocated snakes showed a preference for grassy woodlands associated with hills, but avoided escarpment woodlands and open plains. Floodplain riparian woodland was avoided by resident snakes, but used in proportion to its availability by translocated snakes. Because translocated snakes released at the study site moved larger distances and showed different habitat preferences to resident snakes we conclude that this practice influences individual snakes. Until the implications of translocation for both snakes and humans are fully understood, we recommend caution in the use of this management practice.


2020 ◽  
Vol 3 (1) ◽  
pp. 1-11
Author(s):  
Sampedro AC

To determine the use of the habitat and the patterns of daily activity of two species of psittacids, present in a tropical dry forest in a town in the Montes de María, we make direct observations through point counts, advantageous points and intensive search, in 24 samplings between March and July 2017, between 05:30 and 18:30 hrs. We recorded 421 individuals of Pionus menstruus in 148 sightings and 517 of farmed Amazona in 235 sightings. The largest number of individuals of Pionus menstruus appears in April and May, while the largest number of individuals of Amazona farinosa was observed in July (X = 48.26, p <0.001, 4 df ). The proportion of sightings of these species in zones I and II was similar, but in zone III the number of individuals sighted by A. farinos a was much higher than that of P.menstruus (X2 = 44.718, p <0.001, 2 df ). Both species showed greater activity between 0600 and 0700 and between 1600 and 1800, corresponding to lower values of temperature, wind speed and light intensity than those registered at noon. Most of the sightings occurred during flight for both species. To feed, perch, groom and converse, the parrots used 13 species of trees; among them, Amazona farinosa used 11 to perform three or four activities and Pionus menstruus only used six species to perform three of the activities we observed. The frequency of sighted parrots is related to the availability of ecosystem resources, without any evidence of competition between species.


2020 ◽  
Vol 98 (Supplement_4) ◽  
pp. 60-61
Author(s):  
Elizabeth M Morris ◽  
Susanna E Kitts-Morgan ◽  
Dawn M Spangler ◽  
Kyle R McLeod ◽  
David L Harmon

Abstract Growing public interest in and use of Cannabidiol (CBD) in companion animals has amplified the need to elucidate potential impacts. The purpose of this investigation was to determine the impact of CBD on daily activity of adult dogs. Twenty-four dogs (18.0 ± 3.4 kg) were utilized in a randomized complete block design with treatments consisting of control, 2 mg CBD/kg BW/d, and 4 mg CBD/kg BW/d split between two treats administered after twice-daily exercise (7:00-9:00 and 17:00-19:00). Four hours each day (10:00-12:00, AM and 13:30-15:30, PM), were designated as time when no persons entered the kennels, with 2 h designated as Quiet Time and the other 2 h as Music Time, where calming music played over speakers. Quiet and Music sessions were randomly allotted to daily AM or PM times. Activity monitors were fitted to dogs’ collars for continuous collection of activity parameters. Data were collected over a 2-wk baseline period to block dogs by activity level (high or low) before randomly assigning dogs within each block to treatments. After 1 wk of treatment adaptation, activity parameters were collected for 2 wk. Data were tested for normality using the UNIVARIATE procedure in SAS before examining differences using the MIXED procedure in SAS, including effects of treatment, day, session (Quiet or Music), time of day (AM or PM), and accompanying interactions. CBD did not alter total activity points (P = 0.9971) or activity duration (P = 0.8776). CBD tended (P = 0.0692) to reduce scratching compared to control. Irrespective of treatment, dogs were more active in PM than AM (P &lt; 0.0001). Regardless of session, dogs receiving 4 mg/kg/d tended (P = 0.0914) to be less active in the PM than control. CBD did not affect activity duration during exercise periods (P = 0.1425), but dogs receiving CBD ran more than control (P = 0.0339). These results indicate that when supplemented up to 4 mg/kg/d, CBD does not negatively impact daily activity levels of dogs.


Forests ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 290
Author(s):  
Giacomo Cremonesi ◽  
Francesco Bisi ◽  
Lorenzo Gaffi ◽  
Thet Zaw ◽  
Hla Naing ◽  
...  

The effects of human disturbance represent one of the major threats for wildlife conservation. Many studies have shown that wildlife avoids or reduces direct contact with human activities through changes in activity patterns, and by minimizing spatiotemporal overlap. In this study, we investigated the possible effects of human presence on the temporal activity of medium-to-large mammals using two areas in Myanmar that differ in the intensity of human disturbance. We monitored temporal segregation mechanisms using camera trapping data and with two statistical approaches: daily activity overlaps between humans and wildlife and circular statistics. We did not find a significant difference in overlapping activity between areas but, thanks to circular statistics, we found that some species show changes in activity patterns, suggesting temporal avoidance. We observed that the daily activity of five species differed between areas of Myanmar, likely adopting mechanisms to reduce overlap in areas highly frequented by humans. Interestingly, these species are all threatened by hunting or poaching activities, four of which have been described in literature as “cathemeral”, or species that are active through day and night. This study suggests that some species adapt their behavior, at least partially, to avoid human presence in habitats with higher anthropic occurrence and increase our knowledge on the status of medium–large mammals in a poorly studied country as Myanmar.


2003 ◽  
Vol 285 (5) ◽  
pp. R939-R949 ◽  
Author(s):  
Christopher S. Colwell ◽  
Stephan Michel ◽  
Jason Itri ◽  
Williams Rodriguez ◽  
J. Tam ◽  
...  

The related neuropeptides vasoactive intestinal peptide (VIP) and peptide histidine isoleucine (PHI) are expressed at high levels in the neurons of the suprachiasmatic nucleus (SCN), but their function in the regulation of circadian rhythms is unknown. To study the role of these peptides on the circadian system in vivo, a new mouse model was developed in which both VIP and PHI genes were disrupted by homologous recombination. In a light-dark cycle, these mice exhibited diurnal rhythms in activity which were largely indistinguishable from wild-type controls. In constant darkness, the VIP/PHI-deficient mice exhibited pronounced abnormalities in their circadian system. The activity patterns started ∼8 h earlier than predicted by the previous light cycle. In addition, lack of VIP/PHI led to a shortened free-running period and a loss of the coherence and precision of the circadian locomotor activity rhythm. In about one-quarter of VIP/PHI mice examined, the wheel-running rhythm became arrhythmic after several weeks in constant darkness. Another striking example of these deficits is seen in the split-activity patterns expressed by the mutant mice when they were exposed to a skeleton photoperiod. In addition, the VIP/PHI-deficient mice exhibited deficits in the response of their circadian system to light. Electrophysiological analysis indicates that VIP enhances inhibitory synaptic transmission within the SCN of wild-type and VIP/PHI-deficient mice. Together, the observations suggest that VIP/PHI peptides are critically involved in both the generation of circadian oscillations as well as the normal synchronization of these rhythms to light.


Mammalia ◽  
2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Mauro N. Tammone ◽  
Ulyses F.J. Pardiñas

Abstract Subterranean rodents Ctenomys are iconic representatives of the mammalian fauna from southern South America. Based on molecular data, eight lineages have been identified within the genus, although species-level identifications and relationships are still debated. Until now, the “magellanicus” clade has been the only lineage mentioned from arid, extra-Andean portions of Patagonia. Here, we report the presence of a Ctenomys population from northern Patagonia that is unambiguously associated with the Central Argentinean “mendocinus” lineage. Most of the 160,000 km2 comprising the northern portion of Patagonia – an area consisting primarily of Monte Desert shrub-land – are inhabited by Ctenomys populations of unknown taxonomy.


Sign in / Sign up

Export Citation Format

Share Document