Features of domestic dog demography relevant to rabies control planning in tanzania

Dogs and other canines in the wild 33 FEATURES OF DOMESTIC DOG DEMOGRAPHY RELEVANT TO RABIES CONTROL PLANNING IN TANZANIA Alena Gsella,*, Darryn L. Knobelb, Sarah Cleavelandb, Rudovick R. Kazwalac, Penelope Vounatsoud, Jakob Zinsstagd a Centre for Limnology, Netherlands Institute of Ecology, Netherlands b Centre for Tropical Veterinary Medicine, University of Edinburgh, United Kingdom c Veterinary Medicine and Public Health, Sokoine University of Agriculture, United Republic of Tanzania d Swiss Tropical Institute, Switzerland *Corresponding author: [email protected] Since the 1960s, the reported incidence of dog and human rabies has increased in many countries in southern and eastern Africa, resulting in an estimate of 24,500 human deaths per year in Africa. Mass vaccinations of domestic dogs can effectively control canine rabies and thus human exposure to rabies. An understanding of the structure and demography of dog populations is essential for planning effective rabies vaccination programs; however this information is available for very few African dog populations, particularly in urban areas. This study describes the demographic structure and population dynamics of a domestic dog population in an urban subSaharan African setting. We conducted a full household-level census and a cross-sectional dog demography survey in a domestic dog population in 4 urban wards of Iringa Municipality in the Southern Highlands of Tanzania. The survey was followed by a central point and house-to-house dog vaccination campaign, and all vaccinated dogs were marked with collars for further identification in a transect study assessing the feral dog population. The estimated domestic dog population in Iringa was 6 times larger than official town records assumed. Despite reports of a sizeable feral dog population roaming in the town, the transect study showed that the proportion of feral dogs accounted for only 0.7%-1.5% of the whole dog population. About 13% of households owned 1 or more dogs, and the dog-to-human ratio was 1:14, resulting in 334 dogs per square kilometer. Dog female-to-male ratio was 1:1.3. The population was young, with a mean age of 2.2 years, and 72% of juvenile dogs died within their first year. Females matured sexually at the age of 10 months and reportedly remained fertile up to the age of 11 years. Mature females whelped an average of 5.5 pups per litter about every 1.7 years. Despite the high mortality in the juveniles, population growth was estimated at 10% per year. The high birth and death rates result in a rapid replacement of rabies-immunized individuals with rabies-susceptible ones. This loss in herd immunity needs to be taken into account when designing rabies control programs. The very small proportion of truly feral dogs in the population implies that vaccination campaigns aimed at the owned dog population

63 are sufficient to control rabies in urban Iringa. As many of the demographic characteristics of the Iringa dog population are consistent with findings in other urban African dog populations, the presented results are likely to have widespread relevance for the design of dog vaccination campaigns in urban communities throughout sub-Saharan Africa. Key words: domestic dog demography; feral dog population; urban sub-Saharan Africa; rabies control 34 RED FOX POPULATION DECREASE IN HUNGARY: COMPETITION OR CARRYING CAPACITY LIMITATION? Tama´s Ujhelyi*, Miklo´s Heltai Szent Istva´n University, Go¨do¨ll}o, Institute for Wildlife Conservation, Hungary *Corresponding author: [email protected] In the last two decades the Hungarian red fox (Vulpes vulpes) population (POP) has grown significantly. The growing trend was broken in 2002. We tested two hypotheses: (1) the POP falling due to a fox POP size that is above the carrying capacity (CC) that initiates internal control mechanisms (H1); or (2) a fall in the POP due to competition from the expanding golden jackal POP (H2). Data was collected in one of three ways: (1) voluntary questionnaire survey from Game Management Units regarding estimated (EST) fox POP size; (2) country and countywide hunting (HUNT) bag data from the National Wildlife Database; and (3) POP dynamics (DYN) data obtained from 1,352 dissected fox carcasses. For H1, the pop density was calculated from the EST fox POP size, the hunt mortality (MORT) was calculated from the hunt bag data, and the natural mortality was calculated from the difference between the following year’s EST POP size and the average litter size and stock of the current year. For H2 we examined data from three counties (Baranya, Ba´cs-Kiskun, Somogy) where a considerable breeding golden jackal POP exists. The county data have been compared with each other and with data for the whole of Hungary. The average POP DYN parameters have increased significantly from 1998 to 2002. In 2002, density was 9.47 sp/1,000 hectares, HUNT MORT was 8.2 sp/1,000 hectares, litter size was 7.1 sp, the reproductive (REP) rate for bitches was 55.14%, and the overall reproductive rate was 22.04 sp/1,000 hectares (the natural MORT rate was 15.36). In 2002, the natural mortality rate was nearly two times the HUNT bag rate. The Ba´cs-Kiskun county data parallels the average country’s data. Some differences in Baranya county’s data were noticeable when compared to the country’s data POP DYN parameters were of larger magnitude. In 2002 the POP density was 19.23 sp/1,000 hectares, the HUNT MORT was 9.8 sp/1,000 hectares, the REP rate was 44.77 sp/1,000 hectares, and the natural MORT rate was 42.96 in Baranya county. H1 seems to be supported by our results. POP size was above carrying capacity and internal control mechanisms were at work. The rodent POP decline in 2003 may have assisted in