Fleming P.J.S.,Australian Department of Primary Industries and Fisheries |
Fleming P.J.S.,University of New South Wales |
Nolan H.,University of New South Wales |
Jackson S.M.,Australian Department of Primary Industries and Fisheries |
And 12 more authors.
Food Webs | Year: 2017
The roles of the 37 species in the family Canidae (the dog family), are of great current interest. The Gray Wolf is the largest canid and their roles in food webs are much researched, as are those of Domestic Dogs, Coyotes and Red Foxes. Much less is known about the other canid species and their ecological roles.Here we describe general food web theory and the potential application of network theory to it; summarise the possible roles of predators in food webs; document the occurrence, diet and presumed functions that canids play in food webs throughout the world; give case studies of four threatened canid species of top, middle and basal trophic positions and six anthropogenically affected species; and identify knowledge limitations and propose research frameworks necessary to establish the roles of canids in food webs.Canids can be top-down drivers of systems or responsive to the availability of resources including suitable prey. They can be affected anthropogenically by habitat change, lethal control and changes to basic resource availability. They can be sustainable yield harvesters of their indigenous prey or passengers in complex ecosystems, and some are prey of larger canids and of other predators. Nevertheless, the roles of most canids are generally poorly studied and described, and some, e.g. Gray Wolves, Coyotes and Australian dingoes, are controversial. We advocate mensurative and experimental research into communities and ecosystems containing canids for a quantitative understanding of their roles in food webs and consequent development of better management strategies for ecosystems. © 2017 The Authors.
Pal S.K.,Katwa Bharati Bhaban
Acta Ethologica | Year: 2014
We investigated the effects of sex, age, season and competitive context on the intergroup agonistic behaviour of free-ranging dogs (Canis familiaris). Data were collected in different places to record competitive cooperative behaviour during intergroup conflicts. Observations of 21 free-ranging dogs belonging to four neighbouring groups were made in Katwa town, India. Throughout the 12-month study period, 85 % of all intergroup agonistic interactions recorded were aggressive and 15 % submissive. Intergroup aggressive interactions were more frequent during the late monsoon months when the females were in oestrus, while submissive interactions reached a peak during the winter months when the females were lactating. Adult dogs, particularly males, displayed a higher rate of aggressive behaviour than other age classes, whereas juvenile dogs, particularly males, displayed the highest rate of submissive behaviour. Male dogs were observed to perform more agonistic behaviours in mating contexts and at the boundaries of their territories, whereas female dogs displayed more agonistic behaviours in feeding contexts and in the vicinity of the den. Both aggressive and submissive patterns displayed by the dogs varied with the competitive contexts. The most frequently observed category of aggressive behaviour was ‘barking, growling and snarling’ and submissive behavioural patterns were displayed frequently by ‘lips retracted in a submissive grin’. The striking feature of this study was that in most cases, more than one dog participated in aggressive conflicts. Such cooperative defense predominantly occurred at the boundaries of territory. Group home range size was largest during the late monsoon months and during the winter months. © 2014 Springer-Verlag Berlin Heidelberg and ISPA
Pal S.K.,Katwa Bharati Bhaban
Applied Animal Behaviour Science | Year: 2010
Twenty-four free-ranging dog puppies belonging to six litters were observed from birth to 13 weeks of age to study the play behaviour in early ontogeny. Only a single annual breeding cycle with synchronized breeding season was recorded in this study. Mean litter size was 6.67 ranging from 5 to 8 with a male-biased sex ratio of 1.22:1. Social investigation was first observed with 3 weeks of age, and then subsequently developed other play behaviours (play-fighting, play-mounting, aggressive play, objects play and pseudo-sexual play). The litters were significantly different from each other in relation to the number of total play bouts (χ2=475.42, d.f.=5, P<0.005). The puppies within the litters as well as among the litters were significantly different from each other in relation to the frequency of play bouts. There was a positive correlation between the frequency of play bouts and the number of the puppies within the litters (r=9970, P<0.005). All the play behaviours showing weekly variations increased with the age of the puppies, but it suddenly decreased in weeks 9 or 10, and continued thereafter. Male puppies initiated playful interactions with a greater frequency than did female puppies. Except in the case of aggressive play, male puppies initiated play more often with female puppies and vice versa showing the evidence of inter-sexual play in free-ranging dogs. Intra-sexual dominance relationships among the littermates developed between 5 and 13 weeks of age. © 2010 Elsevier B.V.
Pal S.K.,Katwa Bharati Bhaban
International Journal of Zoology | Year: 2011
Fourteen females belonging to five groups were selected for the study of mating system in free-ranging domestic dogs (Canis familiaris) All the matings occurred between August and December with a peak in late monsoon months (September to November). Both males and females differed in their degree of attractiveness to the opposite sex. The duration of courting association increased with the number of courting males in an association. The females exhibited selectivity by readily permitting some males to mate and avoiding, or even attacking others, if they attempted to mount. Frequency of mounting in courting association increased with the number of males present. There was a positive correlation between the duration of courting association and the frequency of mounting. The young adult males were more likely to copulate successfully than the old adult males. There was a negative correlation between the number of males present in an association and the number of successful copulations. In this study, six types of mating (monogamy, polygyny, promiscuity, polyandry, opportunity and rape) were recorded. Mean (±S.E.) duration of copulatory ties was 25.65 (±1.43) min. Several natural factors influencing the duration of copulatory ties were identified. © 2011 S. K. Pal.