Sixty years of climate impact on Ixodes ricinus (Ixodidae)
摘要
Understanding how long-term climatic changes shape the distribution of disease vectors is essential to anticipate future health and ecological risks. Using long term climatic data (1960–2019) across Europe, we analysed temporal trends, abrupt shifts, and the velocity of climate change in maximum and minimum temperature and vapor pressure deficit (VPD) and evaluated their influence on the climatic niche of the tick Ixodes ricinus. Our results reveal a widespread warming and drying trend, with strong regional heterogeneity. A major regime shift occurred during the 1980s, leading to an abrupt increase of the slope of growth of minimum temperature in northern Europe, or VPD, particularly in the Mediterranean Basin. The length of growing season and accumulated degree days increased markedly after this decade, consistent with a climate tipping point. Despite these shifts, climate velocity remained relatively low (< 5 km year⁻1), indicating that local adaptation of tick populations may buffer spatial displacement. Habitat suitability models show that I. ricinus expanded eastwards and northwards after 1990, with maximum increases of ~ 48% in climatic suitability, yet overall climate niche stability remained high (90–93%) supporting a high niche conservatism. Generalized linear models identified minimum temperature and VPD trends as the main drivers of these changes. Collectively, these findings suggest that recent climate dynamics, particularly after the 1980s, have subtly enhanced the potential range of I. ricinus without major shifts in its core environmental niche. The methods applied in this study could be of particular interest for human health authorities mapping long term resilience of tick populations under the current climate trends.