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Abstract Recently classified as a unique species by the IUCN, African forest elephants (Loxodonta cyclotis) are critically endangered due to severe poaching. With limited knowledge about their ecological role due to the dense tropical forests they inhabit in central Africa, it is unclear how the Afrotropics are influenced by elephants. Although their role as seed dispersers is well known, they may also drive large‐scale processes that determine forest structure through the creation of elephant trails and browsing the understory, allowing larger, carbon‐dense trees to succeed. Multiple scales of lidar were collected by NASA in Lopé National Park, Gabon from 2015 to 2022. Utilizing two airborne lidar datasets in an African forest elephant stronghold, detailed canopy structural information was used in conjunction with elephant trail data to determine how forest structure varies on and off trails. Forest along elephant trails displayed different structural characteristics than forested areas off trails, with lower canopy height, canopy cover, and different vertical distribution of plant density. Less plant area density was found on trails at 1 m in height, while more vegetation was found at 12 m, compared to off trail locations. Trails in forest areas with previous logging history had lower plant area in the top of the canopy. Forest elephants can be considered as “logging light” ecosystem engineers, affecting canopy structure through browsing and movement. Both airborne lidar scales were able to capture elephant impact along trails, with the high‐resolution discrete return lidar performing higher than waveform lidar.

Abstract Anthropogenic eutrophication of ecosystems is an important driver of biodiversity loss. Even protected areas (PAs) may be impacted by anthropogenic nutrients, for example, from atmospheric deposition or the provision of supplementary feeding. However, the resultant nutrient patterns, and the role of local wildlife in shaping them, remain poorly understood. We investigated anthropogenic influences on the role that red deer (Cervus elaphus) play in the nutrient balance of a PA in Denmark. We used habitat selection modeling and theoretical scenarios where we varied the proportion of energy the deer obtained from supplementary versus natural forage and compared it with the nutrients removed due to hunting. We show that the movement and distribution of the red deer population within the PA are very heterogeneous and likely influenced by the need for shelter. Moreover, depending on their reliance on supplementary feeding, deer can potentially import large amounts of nutrients to the PA, and concentrate them in localized hotspots. However, we also explore the potential for nutrient loss due to hunting activities. Such indirect anthropogenic impacts on nutrient landscapes may counteract restoration and conservation efforts. We therefore recommend incorporating anthropogenic influences on zoogeochemistry and the animal‐mediated connectivity between PAs and anthropogenically dominated landscapes into future management plans.

Supplementary feeding of garden birds and gamebirds is a common practice worldwide. Bird feed is rich in phosphorus (P), which plays a key role in animal health and ecosystem function. However, much of the P in bird feed originates from mined rock deposits, which is then transported thousands of kilometers to feeder stations, where it represents an external source of nutrients for recipient ecosystems. Here, we demonstrate that diffusion of P by birds and other animals from feeder stations to ecosystems can represent a nontrivial contribution to local biogeochemical cycles. Using the UK as a case study, we show that supplementary bird feeding supplies 2.4 (range: 1.9–3.0) gigagrams of P per year across the UK, a flux similar in magnitude to atmospheric deposition. Phosphorus provided to garden birds alone is equal to that supplied through the application of garden fertilizers. In natural and semi‐natural ecosystems, additional feeder‐derived P inputs may exacerbate eutrophication at the local scale and adversely impact biodiversity. [ABSTRACT FROM AUTHOR]

Recently classified as a unique species by the IUCN, African forest elephants (Loxodonta cyclotis) are critically endangered due to severe poaching. With limited knowledge about their ecological role due to the dense tropical forests they inhabit in central Africa, it is unclear how the Afrotropics are influenced by elephants. Although their role as seed dispersers is well known, they may also drive large‐scale processes that determine forest structure through the creation of elephant trails and browsing the understory, allowing larger, carbon‐dense trees to succeed. Multiple scales of lidar were collected by NASA in Lopé National Park, Gabon from 2015 to 2022. Utilizing two airborne lidar datasets in an African forest elephant stronghold, detailed canopy structural information was used in conjunction with elephant trail data to determine how forest structure varies on and off trails. Forest along elephant trails displayed different structural characteristics than forested areas off trails, with lower canopy height, canopy cover, and different vertical distribution of plant density. Less plant area density was found on trails at 1 m in height, while more vegetation was found at 12 m, compared to off trail locations. Trails in forest areas with previous logging history had lower plant area in the top of the canopy. Forest elephants can be considered as "logging light" ecosystem engineers, affecting canopy structure through browsing and movement. Both airborne lidar scales were able to capture elephant impact along trails, with the high‐resolution discrete return lidar performing higher than waveform lidar. [ABSTRACT FROM AUTHOR]

Hyaena faeces and mineral licks represent highly concentrated nutrient resources for leopard tortoises (Stigmochelys pardalis) living in nutrient‐poor environments. Here, we provide direct evidence for the consumption of hyaena faeces and artificial mineral licks by leopard tortoises in the Kalahari Desert. Tortoises aggregated at hyaena latrines and lick sites during the wet season between 10 AM and 6 PM in groups of 1–5 individuals. Where both salt and mineral licks were available, tortoises displayed a preference for salt. We suggest that calcium, phosphorus and sodium deficits are likely driving coprophagy and geophagy behaviours by tortoises in the Kalahari. [ABSTRACT FROM AUTHOR]

Ecological restoration is critical for climate and biodiversity resilience over the coming century. Today, there is strong evidence that wildlife can significantly influence the distribution and stoichiometry of elements across landscapes, with subsequent impacts on the composition and functioning of ecosystems. Consequently, any anthropogenic activity that modifies this important aspect of zoogeochemistry, such as changes to animal community composition, diet, or movement patterns, may support or hinder restoration goals. It is therefore imperative that the zoogeochemical effects of such anthropogenic modifications are quantified and mapped at high spatiotemporal resolutions to help inform restoration strategies. Here, we first discuss pathways through which human activities shape wildlife‐mediated elemental landscapes and outline why current frameworks are inadequate to characterize these processes. We then suggest improvements required to comprehensively model, validate, and monitor element recycling and redistribution by wildlife under differing wildlife management scenarios and discuss how this might be implemented in practice through a specific example in the southern Kalahari Desert. With robust ecological forecasting, zoogeochemical impacts of wildlife can thus be used to support ecological restoration and nature‐based solutions to climate change. If ignored in the restoration process, the effects of wildlife on elemental landscapes may delay, or even prevent, restoration success. [ABSTRACT FROM AUTHOR]

Where hyaenas were absent, osteodystrophy in vulture chicks due to Ca and P deficiency occurred in 17% of chicks, but no chicks suffered from this metabolic bone disease at sites where hyaenas were present (Richardson et al., 1986). In this inorganic white powder form (Figure 1c), hyaena faeces mimic the application of bone meal, a common fertiliser for soils, whereby stable Ca phosphates become increasingly soluble with decreasing soil pH (Jeng et al., 2007). Bones contain significant levels of calcium (Ca) and phosphorus (P), which are important to the functioning of terrestrial ecosystems (Carter et al., 2007). [Extracted from the article]