Feral cats overlap with prey and competitors in primary and altered habitats

Bogdan, V., Jůnek, T., & Vymyslická, P. J. (2016). Temporal overlaps of feral cats with prey and competitors in primary and human-altered habitats on Bohol Island, Philippines. PeerJ, 4, e2288.

The vertebrate fauna of the Philippines, known for its diversity and high proportion of endemic species, comprises mainly small- to medium-sized forms with a few large exceptions. As with other tropical ecosystems, the major threats to wildlife are habitat loss, hunting and invasive species, of which the feral cat (Felis catus) is considered the most damaging. Our camera-trapping study focused on a terrestrial vertebrate species inventory on Bohol Island and tempo-spatial co-occurrences of feral cats with their prey and competitors. The survey took place in the Rajah Sikatuna Protected Landscape, and we examined the primary rainforest, its border with agricultural land, and rural areas in the vicinity of villages. Altogether, over 2,885 trap days we captured 30 species of vertebrates–10 mammals (including Sus philippensis), 19 birds and one reptile, Varanus cumingi. We trapped 81.8% of expected vertebrates. Based on the number of events, the most frequent native species was the barred rail (Gallirallus torquatus). The highest overlap in diel activity between cats and potential prey was recorded with rodents in rural areas (Δ = 0.62); the lowest was in the same habitat with ground-dwelling birds (Δ = 0.40). Cat activity was not recorded inside the rainforest; in other habitats their diel activity pattern differed. The cats’ activity declined in daylight in the proximity of humans, while it peaked at the transition zone between rainforest and fields. Both rodents and ground-dwelling birds exhibited a shift in activity levels between sites where cats were present or absent. Rodents tend to become active by day in cat-free habitats. No cats’ temporal response to co-occurrences of civets (Paradoxurus hermaphroditus and Viverra tangalunga) was found but cats in diel activity avoided domestic dogs (Canis lupus familiaris). Our first insight into the ecology of this invasive predator in the Philippines revealed an avoidance of homogeneous primary rainforest and a tendency to forage close to human settlements in heterogeneous habitats. A detailed further investigation of the composition of the cat’s diet, as well as ranging pattern, is still needed.

Dogs in Lombok Island, Indonesia

Mustiana A, Toribio J-A, Abdurrahman M, Suadnya IW, Hernandez-Jover M, Putra AAG, et al. (2015) Owned and Unowned Dog Population Estimation, Dog Management and Dog Bites to Inform Rabies Prevention and Response on Lombok Island, Indonesia. PLoS ONE 10(5): e0124092. doi:10.1371/journal.pone.0124092

Although Indonesia has been rabies-infected since at least the 1880s, some islands remain rabies-free, such as Lombok. However, due to its adjacency to rabies-infected islands such as Bali and Flores, there is considerable risk of a rabies incursion. As part of a rabies risk assessment project, surveys were conducted to estimate the size of the dog population and to describe dog management practices of households belonging to different ethnic groups. A photographic-recapture method was employed and the number of unowned dogs was estimated. A total of 400 dog owning households were interviewed, 300 at an urban site and 100 at a rural site. The majority of the interviewed households belonged to the Balinese ethnic group. Owned dogs were more likely male, and non-pedigree or local breed. These households kept their dogs either fully restricted, semi-free roaming or free-roaming but full restriction was reported only at the urban site. Dog bite cases were reported to be higher at the urban site, and commonly affected children/young adults to 20 years old and males. A higher number of unowned dogs was observed at the urban site than at the rural site. Data generated within these surveys can inform rabies risk assessment models to quantify the probability of rabies being released into Lombok and resulting in the infection of the local dog population. The information gained is critical for efforts to educate dog owners about rabies, as a component of preparedness to prevent the establishment of rabies should an incursion occur.

The demography of free-roaming dog populations and applications to disease and population control

Morters, M. K., McKinley, T. J., Restif, O., Conlan, A. J. K., Cleaveland, S., Hampson, K.,
Whay, H. R , Damriyasa, I M.  & Wood, J. L. N. (2014). The demography of free‐roaming dog populations and applications to disease and population control. Journal of Applied Ecology.


Understanding the demography of domestic dog populations is essential for effective disease control, particularly of canine-mediated rabies. Demographic data are also needed to plan effective population management. However, no study has comprehensively evaluated the contribution of demographic processes (i.e. births, deaths and movement) to variations in dog population size or density, or determined the factors that regulate these processes, including human factors.

We report the results of a three-year cohort study of domestic dogs, which is the first to generate detailed data on the temporal variation of these demographic characteristics. Two communities were monitored at each study site in rabies-endemic areas and where the majority of dogs were free-roaming: Bali, Indonesia and Johannesburg, South Africa. None of the four communities had been engaged in any dog population management interventions by local authorities or animal welfare organizations. All identified dogs in the four communities were monitored individually throughout the study.

We observed either no population growth or a progressive decline in population size during the study period. There was no clear evidence that population size was regulated through environmental resource constraints. Rather, almost all of the identified dogs were owned and fed regularly by their owners, consistent with population size regulated by human demand. Finally, a substantial fraction of the dogs originated from outside the population, entirely through the translocation of dogs by people, rather than from local births. These findings demonstrate that previously reported growth of dog populations is not a general phenomenon, and challenge the widely held view that free-roaming dogs are unowned and form closed populations.

Synthesis and applications. These observations have broad implications for disease and population control. The accessibility of dogs for vaccination and evaluation through owners and the movement of dogs (some of them infected) by people will determine the viable options for disease control strategies. The impact of human factors on population dynamics will also influence the feasibility of annual vaccination campaigns to control rabies and population control through culling or sterilisation. The complex relationship between dogs and people is critically important in the transmission and control of canine-mediated rabies. For effective management, human factors must be considered in the development of disease and population control programmes.