Elisabeth Suzanna Bakker

Scavengers play an important role in ecosystems by removing carcasses. Wild boar ( Sus scrofa ) are facultative scavengers and functionally dominant in ecosystems lacking large carnivores and obligate scavengers, yet the behavioural mechanisms underlying variation in carcass exploitation, and thus carcass removal, remain poorly understood. Due to their social nature, the sounder size – i.e. group size - may influence their scavenging behaviour. We investigated how sounder size influences behavioural transition probabilities of wild boar at carcasses with a focus on eating behaviour. Carcasses were placed in the Netherlands between 2012 and 2021, and monitored with camera traps. For each video, we extracted the primary and secondary behaviour at group-level based on cumulative duration. Behavioural transitions of the group, occurring from one video to the subsequent video, were analysed using binomial Big Additive Models (BAMs) to test the effect of sounder size on behaviour transition probabilities. Larger sounders exhibited a higher probability of remaining in a feeding state, indicating greater feeding persistence. In addition, the probability of transitioning from feeding to intraspecific interaction showed a unimodal relationship with sounder size, peaking at intermediate-sized sounders. These findings suggest that social dynamics and social facilitation influence carcass exploitation by wild boar and may contribute to variation in carcass depletion. By applying behavioural transition analysis to scavenging behaviour, this study provides new insight into the behavioural processes underlying carcass use by a socially foraging vertebrate scavenger.

Nutrient availability in many temperate ecosystems is shaped by soil properties and historical land use. Especially in otherwise nutrient-poor landscapes human-induced, local fertilisation can generate fine-scale mosaics of nutrient hotspots. Whether and how large herbivores respond to such heterogeneity remains poorly understood. We tested whether spatial variation in soil-derived nutrient availability structures habitat selection by large herbivores, using full-year GPS tracking data from 7 red deer (Cervus elaphus) in the Veluwe, the Netherlands. We used soil types as a proxy for nutrient availability and assigned nutrient scores based on soil pH, cation exchange capacity and soil structure. We then evaluated habitat selection across multiple components of space use: (i) home range size; (ii) use of relatively nutrient-rich parts within home ranges; (iii) selection among soil types; and (iv) selection of locally enriched former agricultural patches. Red deer used relatively nutrient-rich within their home range more than expected based on availability, including local patches enriched by former agricultural use. However, site selection did not consistently follow nutrient scores among soil types. These results show that nutrient availability does shape habitat selection, but primarily through fine-scale, localised nutrient enrichment rather than broad-scale variation in soil properties. Our findings demonstrate that nutrient-related foraging contributes to habitat selection in a large wild herbivore, while also revealing that this process is scale- and context-dependent. By repeatedly concentrating their foraging in nutrient-rich patches, large herbivores may contribute to nutrient redistribution across the landscape, with the potential to reinforce or modify existing spatial heterogeneity in resource availability and ecosystem functioning.

With climate and biodiversity crises intensifying, integrated solutions are urgently needed. Rewilding offers a promising approach to ecosystem restoration and climate adaptation. However, challenges regarding land-use, societal conflicts and governance can hinder its implementation. This paper discusses the elements of transformative thinking that can support rewilding implementation and establishment as an innovative approach to ecological recovery. We draw on the lessons learned from over 30 years of rewilding in the Gelderse Poort, the Netherlands. The floodplains in this area have been transformed from a predominantly dry, agricultural landscape into a dynamic riverine nature landscape with a broader range of socio-economic services in a peri-urban area and densely populated region. We describe how a readiness to embrace uncertainty, supportive policies, dedicated champions and innovative funding partnerships were crucial for this rewilding project. We explore how these lessons can inform rewilding efforts in Europe to deliver both climate resilience and biodiversity benefits.

Animals play an important role in elemental cycles that underpin ecosystem functioning through their foraging, movement and waste excretion. Yet animals also play a distinct but often overlooked role in the cycling of trace elements by incorporating potentially scarce trace elements into their tissues and returning significant quantities to the local environment when their carcasses decompose. This gap in our understanding of trace element cycling through animal decomposition means we lack a complete picture of the fundamental zoogeochemical processes that integrate animals within landscapes. Here, we present a perspective on the role large animals play in linking trace elemental cycles from local to landscape scales during their lives (via accumulation and excretion) and after their death (via carcass decomposition). We highlight how large vertebrates, and their decomposition, can redistribute trace elements across spatial scales and may serve as tools for managing trace elemental cycling and enhancing landscape heterogeneity.

Multitrophic interactions can strongly influence the structure and functioning of ecosystems, but how plant diversity influences the direction and predictability of multitrophic interactions across agricultural and natural ecosystems remains unclear. Using 149 field studies across five continents, we found that, on average, increasing plant diversity tended to exert differential top-down and bottom-up effects in croplands versus grasslands and forests. Organic and nonorganic croplands exhibited 846 and 148% higher invertebrate natural enemy-to-herbivore abundance ratios under increased plant diversity, consistent with top-down control patterns where predator gains cause herbivore declines, enhancing crop outcomes. In grasslands and forests, increasing plant diversity was associated with bottom-up effects where enhanced productivity increased both herbivore and predator populations, with the enemy-to-herbivore ratio increasing 4.73% for grasslands and 21.2% for forests. Our findings suggest that biodiversity effects on productivity are not solely explained by direct plant-plant interactions and the resulting biodiversity-productivity relationship. Rather, they reveal patterns consistent with the framework of top-down and bottom-up effects, the relative balance of which may vary depending on ecosystem and management type. The magnitude of the effects of diversified farming on crop pests suggests that crop diversification may be an important avenue for managing crop pests preventatively and thereby enhancing agricultural sustainability.

Masting, highly synchronised but temporally variable seed production, is initiated by weather cues and is thus highly sensitive to climate change. Changes in these cues can lead to a masting breakdown, reducing the fitness benefits of masting through decreasing pollination efficiency and increasing predation risk for seeds. Here, we use 50 years of individual tree data on annual seed production of European beech ( Fagus sylvatica ) in the Netherlands to assess temporal changes in masting patterns and their consequences for the selective benefits of masting. Additionally, we use a novel approach to identify which weather cues initiate reproduction, assess their temporal changes, and test whether they account for the observed changes in masting. We show that synchrony and inter‐annual variation in beechnut production have declined, resulting in a masting breakdown in the late‐2000s, since which there has been constant, but low, seed production each year. Consequently, predation risk increased almost three‐fold, while pollination became less efficient, together reducing the fitness benefits of masting. Seed production was driven by precipitation and temperatures in the year of seed fall and the two preceding years, but the periods within the year in which trees respond to each climate variable differ in both timing and duration. Interestingly, only temperature, not precipitation, has changed over time, but this change only partly explained the observed changes in masting patterns. Masting breakdown is shown across the species range, but its fitness consequences remain understudied, because detailed, individual‐level, long‐term data are required but still rare. By using such a dataset, we here provide crucial evidence for the negative consequences of masting breakdown for beeches through reduced pollination efficiency and increasing predation risk. Using a new methodology, we further underline the strong effects of weather cues on reproduction, while showing that changing climate alone cannot be driving the masting breakdown and must interact with currently unidentified factors.

Ongoing biodiversity loss is one of the pressing issues of our time. Between 1970 and 2020, wildlife populations around the world have decreased by an average of 73% (Shaw et al., 2024). Changes in...