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.