Spatiotemporal variability in activity patterns of urban street cattle as function of environmental factors

Effects of high and low temperatures on the rhythmic patterns in pit-building behavior of antlion larvae

Temperature influences the survival, growth, and development of insects including the antlion. In the present study, we examined the 24-h rhythm in the pit-building behavior of the antlion larvae at three different temperature conditions, high (37°C), low (17°C), and room temperature (Control: 25.9 ± 0.2°C). We recorded pit-building activities by monitoring two variables: the Time Lag for the Initiation of Pit Reconstruction (TLIPR) after the demolition of the pit, and the Total Time for Pit Construction (TTPC). We monitored TLIPR and TTPC at four different time points with equidistant intervals (i.e. 08:00-10:00 h, 14:00-16:00 h, 20:00-22:00 h, and 02:00-04:00 h) each day over three consecutive days. We employed single Cosinor rhythmometry to evaluate the characteristics of 24-h rhythm in TLIPR and TTPC. We used one-way ANOVA to find out the effects of the temperature on TLIPR and TTPC. We detected a statistically significant 24-h rhythm in TLIPR at the group level, irrespective of the temperature conditions. 24-h rhythm in TTPC was abolished at high and low temperatures. Temperature significantly affected TLIPR and TTPC in general. It also significantly affected the mesor of the rhythms in both variables as well as the amplitude of TTPC. Finally, we noted that although high and low temperatures affected the pit-building behavior in general, the thermal conditions did not lead to a complete cessation of pit-building activities. The 24-h rhythmic pattern associated with TTPC is more susceptible to the effects of thermal regimes (17°C or 37°C) unlike that associated with TLIPR.

A population estimation study reveals a staggeringly high number of cattle on the streets of urban Raipur in India

Cattle are cosmopolitan in distribution. They are economically and ecologically significant. The cattle menace on the urban streets of developing and underdeveloped countries is challenging. The number of road accidents is increasing rapidly over time, in the urban areas of most of the developing countries, like India. In the present study, we estimated the population of cattle wandering on the streets/roads/highways of Raipur city of India using the direct headcount method and advanced Photographic Capture-Recapture Method (PCRCM). We compared these two methods of population estimation to check their suitability and adequacy. We superimposed 163 grids (1.0 x 1.0 km each) on the map of Raipur city using Quantum Geographic Information System (QGIS) software. We randomly selected 20 grids for the estimation of the street cattle population. We used both line transect and block count sampling techniques under the direct headcount method. The estimates of visibly roaming cattle on the Raipur city streets were 11808.45 and 11198.30 using the former and the latter sampling techniques, respectively. Further, advanced PCRCM indicated an estimated 35149.61 and 34623.20 cattle using the line transect and block counting sampling techniques, respectively. We observed a female-biased sex ratio in both mature and immature cattle. The frequency of mature cattle was significantly higher than that of naive cattle, followed by the calf. Further, we noticed the frequency of cattle in a grid in the following order: cow > bull > heifer > immature male > female calf > male calf. We concluded that the estimated population of street cattle in Raipur city is about 35 thousand. The results of both the techniques, i.e., direct headcount method and PCRCM, are consistent for population estimation. The direct headcount method yields the number of cattle visibly roaming on the street at a particular time. In contrast, advanced PCRCM gives the total population of street cattle in the city. Active surveillance of the urban cattle population might be of critical importance for municipal and city planners. A better understanding of the urban cattle population might help mitigate the cattle menace on the street, eventually preventing cattle-human conflict and minimizing road accidents. The techniques adopted in this study will also help estimate the population of free-ranging dogs and other wildlife animals in any target location.

Circadian rhythm in behavioral activities and diurnal abundance of stray street dogs in the city of Sambalpur, Odisha, India

This is the first research article that documents circadian variability in behavioral variables, namely resting (Rt) and standing (St) in stray street dogs of Sambalpur city, India. We also estimated the abundance as a function of time of the day and gender in a population of stray dog inhabiting streets of the city. In addition, we determined the association between the behavioral variables and the environmental variables, such as light intensity, sound intensity, temperature and humidity. We determined the abundance of street dogs at 10 hotspots using the photographic capture-recapture technique and Lincoln index equation. In another study, we determined dogs' density along the three randomly selected routes that connect the beginning (Dhanupali) and end (P.C. Bridge) of the city precincts. We recorded the resting and standing activities of the stray street dogs using still and video cameras at four times of the day continuously over a longitudinal timescale of 72 hours. This study was conducted at four randomly selected dog hotspots. Subjecting the log-transformed time series data to the Cosinor rhythmometry we obtained three different rhythm parameters, such as mesor (M), amplitude (A) and acrophase (Ø) of the rhythm in resting and standing behavior of stray street dogs. We found out both spatial and temporal variability in the behavior of street dogs. The sightings of dogs were always more during the evening and nighttime irrespective of the investigated routes and hotspots. Further, we also observed that the abundance of male dogs was always significantly more as compared with the bitches. A lack of association between two attributes the time of the day and gender apropos the number of sightings of the street dogs was validated by the Fisher's exact test. Using Pearson's correlation analysis technique we found a negative relationship between light intensity and resting activity. In addition, we also found a negative association between standing activity and ambient environmental temperature. These findings were complimentary to the observed circadian variability in the resting and standing behavior of the stray street dogs. In conclusion, despite a few limitations, this study documents a statistically significant circadian rhythm in activities of stray street dogs. It also highlights spatial variability in the abundance of dogs on the streets and hotspot localities of the urban Sambalpur. We do have a hunch. It is likely that similar phenomenamight be of common occurrence in many urban areas of the world. These data might also help in addressing street dog menace - one of the major problems the people and administrative authorities of most of the Indian cities and elsewhere worldwide are experiencing since quite long.