Dataset: An invasive commensal and a native marsupial maintain disease vector populations at the urban fringe

Abstract

The dataset contains numbers of larval, nymphal, and adult ticks collected from small mammals in Sydney's Northern Beaches as part of the project focused on identifying the important hosts of urban ticks. The dataset includes unique animal ID numbers, date of sampling, season, transect (1, 2, or 3), animal sex (M = male, F = female), weight, and species.

Study abstract: Vertebrate communities change in response to urbanisation with important flow-on effects for the arthropod disease vectors that use them as hosts. Ticks are major vectors of disease globally making it increasingly important to understand how altered vertebrate communities in urban areas shape tick dynamics and disease risk. Despite looming public health crises in Australian urban landscapes, little is known about which native and introduced small mammals maintain tick populations preventing host-targeted management and leading to human-wildlife conflict. To address this, we determined 1) larval, nymphal, and adult tick abundances on host species and effects of season, host sex and size, 2) the number of ticks supported by the different host populations (tick abundance on each species multiplied by their abundance) and 3) the proportion of medically significant tick species feeding on the different host species in Northern Sydney, Australia. We counted 3551 ticks on 241 individual mammals at 15 sites and found that long-nosed bandicoots hosted more ticks of all life stages than other small mammals but introduced black rats were more abundant at most sites (33-100%) and therefore important in supporting larval and nymphal ticks in our study areas. Black rats and long-nosed bandicoots hosted a greater proportion of medically significant tick species including Ixodes holocyclus and Ixodes tasmani compared to other hosts. Our results show clearly that an introduced commensal contributes to the maintenance of urban tick populations and suggests that ticks could possibly be managed by controlling rat populations on urban fringes.