Dispersal behaviour of free-ranging dogs (Canis familiaris) in relation toage, sex, season and dispersal distance

The dispersal of free-ranging dogs, Canis familiaris, from the town of Katw a, West Bengal, India, was studied from January 1993 to December 1996. Betw een January 1993 and September 1996, 315 pups were observed from 64 litters . Pups were born between October and March each year, with a peak between N ovember and January. The mortality rate was 68% during the first 4 months, with 102 individuals surviving to the juvenile stage (4 to 12 months). In c ase of juveniles, the rate of dispersal was 39.29%, whereas, in case of adu lts it was 23.33%. Mean (+/-S.D.) home range size for the non-dispersing do gs was 4.8 (+/-1.7) ha and for the dispersing dogs was 8.4 (+/-1.7) ha. Mor eover, there were significant seasonal variations in the home range sizes o f both non-dispersing and dispersing dogs. Juvenile males were the predomin ant dispersers. Dispersal occurred in all seasons and dispersal rates did n ot differ between seasons. However, during late monsoon (September to Novem ber), dispersal was greater (P < 0.05) among males than females. The mean ( +/-S.D.) dispersal distance of 1.702 (+/-0.425) km was relatively small, an d did not differ between males and females. (C) 1998 Elsevier Science B.V. All rights reserved.