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Animals representing a wide range of taxonomic groups are known to select specific food combinations to achieve a nutritionally balanced diet. The nutrient balancing hypothesis suggests that, when given the opportunity, animals select foods to achieve a particular target nutrient balance, and that balancing occurs between meals and between days. For wild ruminants who inhabit landscapes dominated by human land use, nutritionally imbalanced diets can result from ingesting agricultural crops rich in starch and sugar (nonstructural carbohydrates [NCs]), which can be provided to them by people as supplementary feeds. Here, we test the nutrient balancing hypothesis by assessing potential effects that the ingestion of such crops by Alces alces (moose) may have on forage intake. We predicted that moose compensate for an imbalanced intake of excess NC by selecting tree forage with macro-nutritional content better suited for their rumen microbiome during wintertime. We applied DNA metabarcoding to identify plants in fecal and rumen content from the same moose during winter in Sweden. We found that the concentration of NC-rich crops in feces predicted the presence of Picea abies (Norway spruce) in rumen samples. The finding is consistent with the prediction that moose use tree forage as a nutritionally complementary resource to balance their intake of NC-rich foods, and that they ingested P. abies in particular (normally a forage rarely eaten by moose) because it was the most readily available tree. Our finding sheds new light on the foraging behavior of a model species in herbivore ecology, and on how habitat alterations by humans may change the behavior of wildlife., Funding agencies:Swedish Research Council for Sustainable Development 2016‐01140Swedish Environmental Protection Agency 13/274Södra Research Fund 2020‐00108Swedish Hunting Association 5909/2021

Foraging on crops by wild ungulates may create human–wildlife conflicts through reducing crop production. Ungulates interact with and within complex socio-ecological systems, making the reduction of crop damage a challenging task. Aside from ungulate densities, crop damage is influenced by different drivers affecting ungulate foraging behaviour: food availability and food quality in the landscape (i.e. the foodscape) as well as fear from hunting and scaring actions (i.e. the landscape of fear) may together affect the degree of damage via both direct and indirect effects. A better understanding of the individual effects of these potential drivers behind crop damage is needed, as is an appreciation of whether the effects are dependent on ungulate density. We investigated this by applying path analysis to test indirect and direct links between ungulate density, foodscape, landscape of fear and human management goals on crop damage of oats and grass, respectively. Our results suggest that crop type is the major driver behind crop damage, with more damage to oats than to leys, implying that human decisions (i.e. changing crop type) influence the level of crop damage. We found that management goals and actions influenced the foodscape and the landscape of fear, by affecting the amount of forage produced in the agricultural landscape and the amount of scaring actions. Additionally, we found that supplementary feeding influenced the local ungulate densities in the area. Our results highlight the importance of including human actions on multiple levels when assessing drivers behind damage by ungulates in managed landscapes. We suggest that more studies using path analysis on multiple scales are needed in order to tackle complex issues, such as crop damage and other human–wildlife conflicts.

Foraging on crops by wild ungulates may create human-wildlife conflicts through reducing crop production. Ungulates interact with and within complex socio-ecological systems, making the reduction of crop damage a challenging task. Aside from ungulate densities, crop damage is influenced by different drivers affecting ungulate foraging behavior: food availability and food quality in the landscape (i.e. the foodscape) as well as fear from hunting and scaring actions (i.e. the landscape of fear) may together affect the degree of damage via both direct and indirect effects. A better understanding of the individual effects of these potential drivers behind crop damage is needed, as is an appreciation of whether the effects are dependent on ungulate density. We investigated this by applying path analysis to test indirect and direct links between ungulate density, foodscape, landscape of fear and, human management goals on crop damage of oats and grass, respectively. Our results suggest that crop type is the major driver behind crop damage, with more damage to oats than to leys, implying that human decisions (i.e changing crop type) influence the level of crop damage. We found that management goals and actions influenced the foodscape and the landscape of fear, by affecting the amount of forage produced in the agricultural landscape and the amount of scaring actions. Additionally, we found that supplementary feeding influenced the local ungulate densities in the area. Our results highlight the importance of including human actions on multiple levels when assessing drivers behind damage by ungulates in managed landscapes. We suggest that more studies using path analysis on multiple scales are needed in order to tackle complex issues such as crop damage and other human-wildlife conflicts., Foraging on crops by wild ungulates may create human-wildlife conflicts through reducing crop production. Ungulates interact with and within complex socio-ecological systems, making the reduction of crop damage a challenging task. Aside from ungulate densities, crop damage is influenced by different drivers affecting ungulate foraging behavior: food availability and food quality in the landscape (i.e. the foodscape) as well as fear from hunting and scaring actions (i.e. the landscape of fear) may together affect the degree of damage via both direct and indirect effects. A better understanding of the individual effects of these potential drivers behind crop damage is needed, as is an appreciation of whether the effects are dependent on ungulate density. We investigated this by applying path analysis to test indirect and direct links between ungulate density, foodscape, landscape of fear and, human management goals on crop damage of oats and grass, respectively. Our results suggest that crop type is the major driver behind crop damage, with more damage to oats than to leys, implying that human decisions (i.e changing crop type) influence the level of crop damage. We found that management goals and actions influenced the foodscape and the landscape of fear, by affecting the amount of forage produced in the agricultural landscape and the amount of scaring actions. Additionally, we found that supplementary feeding influenced the local ungulate densities in the area. Our results highlight the importance of including human actions on multiple levels when assessing drivers behind damage by ungulates in managed landscapes. We suggest that more studies using path analysis on multiple scales are needed in order to tackle complex issues such as crop damage and other human-wildlife conflicts.

The distribution and population density of red deer (Cervus elaphus) are increasing in several regions of Europe. The deer may cause severe damage in commercial forestry and agriculture. Bark stripping is the main problem in forests, especially on Norway spruce (Picea abies), and is thought to mostly occur during winter when other forage is scarce. It has been suggested that an imbalance in the nutrient intake, and especially a diet including high amounts of easily-digestible macronutrients, such as agricultural crops, can lead to an increased urge to consume bark. Feeding on brassicas, for example rapeseed (Brassica napus) might have this effect. The aim with this study was to investigate the relationship between intake of rapeseed and bark stripping on Norway spruce by red deer during early spring. We did this by a controlled feeding experiment with four groups of captive red deer in southern Sweden. All groups were given spruce logs every week, while only two groups had access to freshly harvested rapeseed plants. In addition, influence of air temperature and forage nutritional composition was taken into account. Our results show that red deer bark stripping can be considerable not only during winter but also during spring green-up. We found no significant influence of rapeseed on bark stripping performed by the deer. However, at a threshold temperature, deer suddenly started to ingest large amounts of bark biomass, coinciding with a significant change in the bark's concentration of starch. We suggest that the lack of effect of rapeseed feeding can partly be explained by overshadowing effects caused by such seasonal changes of bark character-istics, and partly by the fact that the rapeseed plants in our study contained lower than expected concentrations of easily-digestible macronutrients (apart from protein). We conclude that the risk of damage on spruce can be especially high during certain periods, something that is important to consider when mitigating bark s

Populations of large herbivores, including members of the deer family Cervidae, are expanding across and within many regions of the northern hemisphere. Because their browsing on trees can result in economic losses to forestry and strongly affect ecosystems, it is becoming increasingly important to understand how best to mitigate resultant damage. Previous research has highlighted the importance of regulating deer density and the availability of alternative forage to reduce browsing damage levels in conifer production stands. However, often only one or two proxies of forage availability have been used instead of applying a broad foodscape approach and more knowledge is needed to understand which types of alternative forage best mitigate damage. We conducted field inventories of damage that occurred during the previous fall/winter in 112 production stands in southern Sweden, while also measuring forage availability and cervid faecal pellets in the surrounding landscape (16 ha). Local landowners provided data on supplementary feeding. We found that variation in cervid (Alces alces, Capreolus capreolus, Cervus elaphus and Dama dama) browsing damage to top shoots or stems of young Scots pine trees (Pinus sylvestris, hereon pine), was better explained by the availability of alternative natural forage (using several indices and species of trees and shrubs) than by supplementary feeding. The proportion of damaged pine trees was higher in stands with a lower density of pine stems; in landscapes with a lower density of key broadleaf tree species (genera Sorbus, Salix, Populus and Quercus); and in landscapes with more open land (agricultural fields and paddocks). Damage was also higher in stands where relatively large amounts of moose faeces was found, while not related to the amount of faeces from other cervid species. The amount of supplementary feed (silage or other types such as root vegetables) did not explain variation in pine damage, but the result was possibly affecte

Deer can show transitional use between agricultural fields and forests for foraging and shelter. Such transitional use may affect forest damage as nutrient balancing theory suggests that if deer ingest large amounts of nutrient-rich food, complementary browse, such as bark, may be required to balance the diet. We investigated the relationship between the level of red deer Cervus elaphus bark-stripping damage in 68 Norway spruce Picea abies stands and the presence of rapeseed Brassica napus fields – an energy-rich crop preferred by red deer – in the surroundings, hypothesizing that damage increases with decreasing distance to rapeseed fields. We also considered other potentially influencing factors, such as supplemental feeding, alternative forage availability, and deer use of spruce stands as indexed by a pellet group count. Spruce stands closer to rapeseed had a significantly higher proportion of damaged stems. The increased level of bark-stripping damage was not explained by a higher stand use of deer closer to rapeseed fields, indicating that deer increase their consumption of bark in order to balance their diet. Similarly, spruce stands closer to supplemental feeding stations had significantly higher damage levels. In line with earlier findings, damage levels were negatively related to the amount of available browse in the forest. This emphasizes the importance of alternative forage for reducing the damage risk in forest plantations. Our study shows that the availability of fields with nutrient-rich food, such as rapeseed, as well as supplemental feeding needs to be considered when predicting the level of forest damage. With a high availability of nutrient-rich food in the vicinity of forest stands, a higher damage level can be expected and counteractions could be taken such as increased disturbance, harvest or changed choice of both crop and supplemental feed types. These actions may also be combined with a push–pull strategy where the deer are steered to distu

There is increasing empirical support for the biodiversity and ecosystem service (ES) benefits of mixed-species production forests. However, few studies control for the spatial arrangement of the trees within mixtures to determine the influence that clustering the tree species (patch scale mixtures), versus evenly dispersing them (intimate scale mixtures), may have for biodiversity and ES outcomes. To highlight the potential implications of altering tree spatial arrangement in mixtures, and the need to fill related knowledge gaps, here we provide a qualitative multi-disciplinary overview of ecological and socio-economic drivers with the potential to alter biodiversity, ecosystem services, and management-related outcomes from patch versus intimate scale mixtures. We focused our overview on even-aged mixtures of Norway spruce (Picea abies) and birch (Betula pendula or B. pubescens) in Sweden, which enabled us to contrast findings within a biogeographical and silvicultural setting. Specifically, we targeted implications for biodiversity (understory vascular plants, epiphytic lichens, saproxylic beetles, birds), biomass production, harvesting costs, management ease, recreation and aesthetics, cervid game, as well as abiotic and biotic risks (wind, fire, pathogens, pests, browsing damage). In the absence of direct empirical evidence, we primarily relied on expert inference from theory and relevant empirical studies sourced from the Fennoscandian region, and further afield if needed. Collectively these efforts allowed us to develop a number of informed hypotheses indicating that for spruce-birch mixtures in this region, patch scale mixtures may have the potential to favour the diversity of several forest dependant taxonomic groups, cervid game and reduce harvesting costs, whereas intimate mixtures may have the potential to reduce pathogen and pest damage, and likewise, potentially benefit production outcomes. Current knowledge was too limited, inconsistent or context depe

Crop raiding ungulates can cause costly yield losses and conflicts between agriculture, game management, and conservation. It is therefore crucial to know how, where, and when ungulates use different habitats and crops. In this study we used resource selection functions and GPS-tagged red deer Cervus elaphus (n = 38) in two different study areas (North – mainly forested land and South – mainly arable land), to investigate how red deer use arable land and different crop types in relation to availability and distance to forest cover in Sweden. Our study shows a transitional use of arable land and forests by red deer. Red deer spend on average 45% and 21% of their time in arable land in South and North respectively. In the North, arable land was selected while forest and wetlands were selected in the South. The selection of different crops also differed between the two study areas, for example rapeseed was highly selected during both seasons in South while it was used to a lower degree in relation to its availability in the North. In both study areas the probability of red deer presence on the agricultural fields decreased with distance to forest. The significant use of arable land and unharvested crops by the increasing red deer population in Sweden highlights a risk for crop damage that may need further consideration for farming practices as well as for damage and wildlife management. In our case damage mitigation should focus on rapeseed in the South, whereas there is a less clear pattern of selection among growing crops in the North. The differences in habitat and crop selection between the two areas also highlights the need of knowledge about red deer habitat selection at a regional level to be able to adapt damage mitigation and wildlife management strategies accordingly. Moreover, the transitional use of arable land and forests by red deer in mixed landscapes may imply that consumption of certain crops can affect browsing patterns and damage levels within forest, Funding: Swedish University of Agricultural Sciences, Swedish Association for Hunting and Wildlife Management, Holmen Skog AB, Ittur AB, Vira Bruk AB, Karl-Erik Önnesjös stiftelse for vetenskaplig forskning och utveckling, Högestad & Christinehofs Förvaltnings AB, Region Skåne/Stiftelsen Skånska Landskap, Stiftelsen Oscar och Lili Lamms Minne & Kolmårdens insamlingsstiftelse/Täby Allmänning