European mistletoe shares a similar demographic strategy with non‐parasitic plants

Abstract The demographic strategies of parasites are fundamental to their population dynamics, impacts, responses to environmental change and management. Parasitic plants are an economically important group of parasites that differ from non‐parasitic plants in their unique resource acquisition mechanisms and various morphological and ecological adaptations. Though they are well‐suited to demographic study, structured population models have rarely been applied to parasitic plants. Thus, whether or not parasitic plants also differ from non‐parasitic plants in their demographic strategies remains poorly understood. Using a 10‐year dataset on European mistletoe ( Viscum album ) parasites, we quantified the relationship between mistletoe traits and vital rates. We used vital rate regressions to parameterise an integral projection model (IPM), from which we extracted time‐based life history traits to quantify mistletoe's demographic strategy. To compare the demographic strategies of parasitic plants and non‐parasitic plants, we performed a principal component analysis (PCA) of life‐history traits for mistletoe, two other parasitic plants and 498 non‐parasitic plant species. We found that individual mistletoe growth rate and fruiting probability depend on mistletoe size, a proxy for mistletoe age. Fruiting probability also depends on the mistletoe's vertical position on the host, whereas mistletoe survival was independent of size and position. Mistletoe life‐history traits were most sensitive to changes in individual mistletoe growth rate and then to survival, though generation time was also sensitive to changes in reproduction. Contrary to our expectation, V. album and other parasitic plants placed centrally in our PCA of demographic strategies, near the centre of both the fast–slow continuum and reproductive strategy axis. This suggests that parasitic plants and non‐parasitic plants share a similar demographic strategy, at least as summarised by our chosen life‐history traits. Synthesis . Our results suggest that the unique adaptations of parasitic plants do not prevent them from experiencing similar demographic constraints to non‐parasitic species. If parasitic plants exhibit unique responses to global change compared to non‐parasites, there is insufficient evidence to suggest that this is driven by differences in life history. Our conclusions support a general view that population‐level behaviour is similar between parasitic and non‐parasitic plants.