Estimation of roaming dog populations in Timor Leste

The continued spread of rabies through the eastern islands of Indonesia poses a risk of rabies introduction to Timor Leste. To prepare for such an incursion and to undertake surveillance activities, the size and distribution of the roaming dog population needs to be estimated. We present the results of the first such surveys ever undertaken in Timor Leste. Roaming dog surveys were undertaken in each capital of the 13 districts of Timor Leste, including the national capital, Dili. Within these locations, local urban areas (aldeias) were targeted and sight-re-sight counts were undertaken on consecutive days. Estimated dog populations were adjusted for the sampling fraction. Overall, counts were performed in a total of 53 of 131 (40.5%) sucos and in 192 of 797 (24.1%) aldeias in these selected sucos. Within the surveyed urban areas, there were an estimated 21.2 people per roaming dog, a ratio substantially higher than the World Health Organization's average global estimate of 10 people per dog. The highest populations of dogs were estimated in the cities of Dili (4919), Baucau vila (3449) and Lospalos (2536). The latter two are important because of their location in the northeast of Timor Leste, where the risk of rabies incursion from recently infected islands in eastern Indonesia, is likely greatest. The sight-resight method of estimating roaming dog populations is practical in developing countries; more use of photography to aid resighting of dogs could increase the accuracy of this method.