The Association of Urban Greenspace Characteristics with Tick Densities and Borrelia burgdorferi prevalence in Scotland

Ackers Johnson, Simona

Abstract

Ticks are an ecosystem disservice in urban greenspaces, with the potential to transmit diseases. The characteristics of an urban greenspace can impact the hazard of ticks and tick-borne pathogens both within a greenspace and in the surrounding area. This research aimed to understand how the configuration, connectivity, area, and land cover of urban greenspaces can influence the population densities of ticks and the associated hazard of Borrelia burgdorferi, the agent of Lyme disease. Tick densities were estimated at 34 sites across Scotland in 2022 and 2023, and tick samples were analysed to detect the prevalence of B. burgdorferi pathogens. The area and connectivity of each greenspace was calculated, as well as the proportions of four land cover types within a 1 km buffer around each greenspace. An agent-based model was used to explore how the configurations of single large vs several small greenspaces may influence the risk of tick bites and Borrelia infections. Increased connectivity of urban greenspaces was significantly correlated with increased density of nymphs (DON) and the density of infected nymphs (DIN) within greenspaces. Increased greenspace area was associated with increased DIN, but not DON. Land cover was found to have varying effects on DON and DIN; Increased woodland cover was associated with increased DIN but decreased DON. The proportion of built-up area was negatively associated with the DIN. Increased areas of improved grassland were associated with increased DIN, while the proportion of semi-natural grassland had the opposite effect. Modelling outputs suggested that while the risk of tick bites may be significantly higher in a ‘several small’ greenspace configuration, the risk of Borrelia infections is significantly higher in a ‘single large’ greenspace. These results highlight the need for urban planners to recognise these potential disservices when designing greenspaces, and the importance of educating the public about tick awareness.

• Thesis Type: Thesis
• Deposit Date: Jan 6, 2025
• Publicly Available Date: Feb 24, 2025
• Keywords: Urban Greenspace, Ecosystem Disservices, Connectivity, Tick-borne Disease
• Award Date: Jan 23, 2025