Intensive Agricultural Landscapes Research Articles

Semi-natural habitats mitigate the impact of food shortage on honey bees in farmlands

Landscape simplification and the loss of semi-natural habitats are identified as important drivers of insect pollinator decline in farmlands, by disrupting the availability of floral resources and facilitating the occurrence of food shortages. Food shortages can lead to accelerated behavioral maturation in honey bees, with potential consequences for colony survival. However, little is known about the magnitude of behavioral maturation mediated by to food shortage under real field conditions, and whether it could be mitigated by the presence of semi-natural habitats. Here, we monitored the lifespan (LSP), age at first exit (AFE), foraging tenure, and foraging intensity of 1035 honey bees along a landscape gradient of semi-natural habitats in farmlands. We found a clear acceleration of behavioral maturation of bees during the food shortage season, with precocity in AFE between 6 and 10 days earlier and reduced LSP by 5 to 9 days, with no effect on foraging tenure or foraging intensity. We also found that higher proportions of semi-natural habitats mitigated behavioral maturation of bees by up to 6 days. Beyond the direct effects on adult bees, we found no delayed effect of larval feeding status on adult life-history traits or foraging behavior. Nevertheless, our results strongly advocate the implementation of policies aimed at increasing the coverage of semi-natural environments (e.g., grasslands, forests, hedgerows) in intensive agricultural landscapes to support honey bee survival and pollinator conservation.

Ecological and functional niches comparison reveals differentiated resource‐use strategies and ecological thresholds in four key floating‐leaved macrophytes

AbstractNiche theory has been widely used in ecology; however, few studies have attempted to combine information on functional and ecological niches (i.e., variation in traits and environmental requirements), especially for freshwater macrophytes. In this study, we aim to describe the functional and ecological niches of four key nymphaeid species (Nuphar lutea, Nymphaea alba, Nelumbo nucifera, and Nymphoides peltata) to investigate their environmental tolerance and functional adaptability. Twelve Italian populations per species were sampled. Functional and ecological niches were determined using hypervolumes based on eight functional traits and environmental variables, related to leaf structure and economics spectrum, and to water and sediment quality. Among the three Italian native species, N. lutea and N. alba showed intermediate niche size and position in the functional and ecological space, although N. alba appears to be less competitive due to a small functional niche and lower trait performance, which could explain its general tendency to decline. N. peltata appeared more specialized in its environmental requirements and characterized by highly acquisitive leaves, while the invasive alien N. nucifera exerted its competitive success by distinguishing its functional niche and expanding its ecological niche, through high investment of resources in leaves. Overall, all four target species share similar ecological niches, colonizing eutrophic ecosystems typical of intensive agricultural landscapes, but show different patterns in their functional niche. We demonstrate the applicability of an approach based on both functional and ecological niches to unravel species' adaptation and strategies.

Impacts of hydrologic management on the eutrophication of shallow lakes in an intensive agricultural landscape (Saskatchewan, Canada)

Abstract Hydrologic management of shallow lakes is often undertaken to prevent fluctuations in lake level, and to ensure sufficient water volume for economic, domestic, and recreational uses, but there is inconsistent evidence of whether lake‐level stabilisation through hydrological management promotes or hinders eutrophication. Here we used multi‐proxy paleolimnological assessments of water quality (sedimentary carbon, nitrogen, total phosphorus, fossil pigments), and zooplankton community ecology (fossil Cladocera assemblages), combined with Landsat‐derived estimates of lake surface area in two shallow eutrophic lakes, in the Prairies of southern Saskatchewan, Canada, to quantify how 8 decades of contrasting hydrological management strategies (continuous or intermittent) affect primary production and phytoplankton composition. Analysis revealed that irregular hydrological management of Pelican Lake led to sharp increases in primary production concomitant with lake‐level decline. In contrast, continuously managed Buffalo Pound Lake, a drinking water reservoir for regional cities, exhibited slow, persistent eutrophication over decades despite active regulation of water levels. In both lakes, strong correlations of δ 15N values with pigments from diazotrophic cyanobacteria (canthaxanthin) showed that N2‐fixation increased during eutrophication irrespective of the timing of change. Finally, variation in fossil cladoceran density and composition reflected changes in pelagic and littoral habitats (e.g., reduced macrophyte cover) due to changes in both lake level and water quality. Basin comparison shows that while hydrologic management can moderate water quality degradation due to lake‐level change, it does not prevent eutrophication when nutrient influx remains high. Given that regional water availability is forecast to decline in coming decades, we anticipate that continued hydrological management will be unavoidable and will be unable to improve water quality unless nutrient influx is also controlled.

Improved Wetland Mapping of a Highly Fragmented Agricultural Landscape Using Land Surface Phenological Features

Wetlands are integral components of agricultural landscapes, providing a wide range of ecological, economic, and social benefits essential for sustainable development and rural livelihoods. Globally, they are vulnerable ecological assets facing several significant threats including water extraction and regulation, land clearing and reclamation, and climate change. Classification and mapping of wetlands in agricultural landscapes is crucial for conserving these ecosystems to maintain their ecological integrity amidst ongoing land-use changes and environmental pressures. This study aims to establish a robust framework for wetland classification and mapping in intensive agricultural landscapes using time series of Sentinel-2 imagery, with a focus on the Gwydir Wetland Complex situated in the northern Murray–Darling Basin—Australia’s largest river system. Using the Google Earth Engine (GEE) platform, we extracted two groups of predictors based on six vegetation indices time series calculated from multi-temporal Sentinel-2 surface reflectance (SR) imagery: the first is statistical features summarizing the time series and the second is phenological features based on harmonic analysis of time series data (HANTS). We developed and evaluated random forest (RF) models for each level of classification with combination of different groups of predictors. Our results show that RF models involving both HANTS and statistical features perform strongly with significantly high overall accuracy and class-weighted F1 scores (p < 0.05) when comparing with models with either statistical or HANTS variables. While the models have excellent performance (F-score greater than 0.9) in distinguishing wetlands from other landcovers (croplands, terrestrial uplands, and open waters), the inter-class discriminating power among wetlands is class-specific: wetlands that are frequently inundated (including river red gum forests and wetlands dominated by common reed, water couch, and marsh club-rush) are generally better identified than the ones that are flooded less frequently, such as sedgelands and woodlands dominated by black box and coolabah. This study demonstrates that HANTS features extracted from time series Sentinel data can significantly improve the accuracy of wetland mapping in highly fragmentated agricultural landscapes. Thus, this framework enables wetland classification and mapping to be updated on a regular basis to better understand the dynamic nature of these complex ecosystems and improve long-term wetland monitoring.

Hirundo rustica (Barn Swallows) and Tachycineta bicolor (Tree Swallows) select wetlands in agriculturally intensive landscapes, as revealed by GPS tracking

Abstract Aerial insectivorous birds breeding in North America have experienced decades of population declines for reasons hypothesized to be related to changes in their insect prey. In agricultural landscapes, land management practices can affect insect communities, leading to concerns that ongoing trends toward more intensive cultivation could affect the ability of farmland-breeding aerial insectivores to forage and provision their offspring with aerial insect prey. To understand how differences in agricultural intensity may affect the foraging behavior of different aerial insectivore species, we used GPS tags to compare the movements and habitat use of 2 species with different foraging ecologies, Hirundo rustica (Barn Swallow) and Tachycineta bicolor (Tree Swallow), breeding at 17 sites in agricultural landscapes in Saskatchewan, Canada. Although we identified differences in foraging behavior consistent with each species’ reported ecological traits, including T. bicolor foraging farther and over larger areas than H. rustica, overall foraging behavior was similar between species. Resource selection function analyses indicated that both species used wetlands disproportionately often relative to local wetland availability, especially when detected farther from their nests. Hirundo rustica and T. bicolor both also avoided cropped foraging habitat, using it proportionally less than it was locally available. In landscapes with greater wetland cover, both species selected for wetland habitat more strongly, and among T. bicolor, higher wetland density decreased maximum foraging distance and home range area. In contrast, we found no effect of crop cover on foraging habitat selection or foraging movements. These findings suggest that H. rustica and T. bicolor breeding in Saskatchewan agroecosystems share similar foraging strategies, with wetland habitats appearing to be highly important despite comprising only a small proportion of landscape area. Overall, these results indicate that protecting wetland habitats should be a priority for aerial insectivore conservation in the intensive agricultural landscapes such as the Canadian prairies.

Lowland forest fragment characteristics and anthropogenic disturbances determine alien plant species richness and composition

Loss of habitat and biological invasion are the main threats to biodiversity. In intensive agricultural or urban landscapes, forest fragments, even if they are small and isolated represent biodiversity refugia. Environmental variables such as landscape structure, abiotic conditions and anthropogenic disturbance affect the biodiversity of the fragments. In this study, we explored plant species richness in 48 forest fragments embedded in predominantly agricultural landscapes on the alluvial plains of the Mura and Drava rivers in NE Slovenia. We determined several forest fragment characteristics such as perimeter, area, shape complexity, length and proportion of edge shared with adjacent land-cover types and anthropogenic disturbance indicated by the presence of footpaths and waste disposed in fragments. The abiotic condition of these fragments was assessed by Ellenberg indicator values. We built generalized linear models and ordination analyses to assess the importance of environmental variables for the richness and composition of alien plant species and other ecologically meaningful plant groups. Shape complexity had a consistent positive effect on the richness of native and alien plants species. Major drivers of alien plant composition in forest fragments included adjacent land-cover and urbanization level. An increasing proportion of arable land along the forest fragment perimeter negatively affected the richness of alien plants, while the effect of urban areas was positive. Our results confirmed that forest fragments in the rural–urban matrix represent biodiversity refugia and support native plant species; however, they are not resistant to invasions; instead invasion depends on the land-cover type in the surroundings of a given forest fragment.

Survival of northern pintail ducklings in grasslands and croplands: implications for fall‐seeded cereals

AbstractSpecies‐specific management strategies have been implemented to address persistently low continental populations of several duck species, including the northern pintail (Anas acuta). In the Canadian Prairie Pothole Region (PPR), addressing threats from spring‐seeded cereals on pintail productivity may provide sufficient gains to recover populations. Research on pintail duckling ecology has revealed that duckling survival may be greater in grassland‐dominated landscapes than in annual cropland‐dominated landscapes, possibly limiting the benefits of fall‐seeded cropping practices. Winter wheat crops increase nest success and may assist nesting pintail populations through provision of nesting refuges from spring tillage operations, earlier hatch, and greater nest densities compared to traditional spring‐seeded cereal crops. Yet inadequate duckling survival may reduce these benefits. Our principal objective was to examine if pintail reproductive success in winter wheat in cropland‐dominated landscapes was comparable to grassland‐dominated landscapes or, alternatively, if duckling survival rates in cropland‐dominated landscapes offset the gains of greater nesting success in winter wheat. We captured and radio‐marked 104 nesting female pintails in grasslands and croplands of southern Saskatchewan, during 2011–2012. We modeled cumulative survival to 30 days post hatch in relation to landscape composition and land cover type, specifically, the influence of nesting in fall‐seeded crops. Predicted 30‐day survival for ducklings hatched in perennial cover (40.8% [85% CI = 40.0–44.6%]) in grassland‐dominated landscapes and winter wheat (38.2% [32.0–44.4%]) in cropland‐dominated landscapes was more than double survival of ducklings hatched in spring‐seeded cropland (16.9% [12.6–21.6%]) in cropland‐dominated landscapes. Ducklings moving through local environments with more perennial cover and seasonal wetlands, but less wetland edge, had increased survival. The benefit of greater nest survival in winter wheat was not completely superseded by reduced duckling survival for broods raised in intensive agricultural landscapes. The retention of grassland landscapes and expansion and promotion of fall‐seeded crops in cropland‐dominated landscapes can benefit northern pintails across broad regions of the PPR.

Use of linear features by red-legged partridges in an intensive agricultural landscape: implications for landscape management in farmland

Use of linear features by red-legged partridges in an intensive agricultural landscape: implications for landscape management in farmland

The reuse of Song Thrush (Turdus philomelos) nests by the Red-backed Shrike (Lanius collurio) in an intensive agricultural landscape: a coincidence or a new solution?

Nest site availability plays an important role in the ecology of the birds inhabiting intensive agricultural landscapes. The removal of trees and snags due to logging is one of the main threats and the cause of the observed decline in many birds living in an agricultural landscape. When nests are lost, nesting passerines typically rebuild them for a new clutch. Additionally, relocating nests after a brood loss is a prevalent strategy used to avoid predators and brood parasites. Such a strategy is common to the Red-backed Shrike, which builds successive nests for each brood. Interestingly, clutch replacement may occur in unusual forms. This study describe three cases of Song Thrush nests reused by Red-backed Shrikes during one breeding season. The time and energy-saving behaviour or possible deterrence of nest parasitism could explain why the nests have been reused. However, due to the limited observations as compared to the total number of nests, further research is necessary to clarify this phenomenon.

Timing of reed management affects habitat use and breeding success in Great Reed Warblers: A field experiment on agricultural drainage canals

Freshwater wetlands and their biodiversity have suffered substantial losses globally, mainly due to the drainage of wetlands for agriculture. Recent studies suggest that small drainage and/or irrigation canals established in lowland areas can function both as partial replacement of wetlands lost and as biodiversity hotspots in agricultural landscapes. However, small canals are usually not protected or managed for biodiversity. We studied whether and how the timing of reed management (removal in winter, in spring, no removal) on small canals affects nest site selection and breeding success in Great Reed Warblers, Acrocephalus arundinaceus, a flagship species of small canals in an intensive agricultural landscape in a five-year quasi-experiment. We found significantly more nests in winter-managed than in non-managed canal sections and hardly any in spring-managed sections. The number of nests also increased with the proportion of reed removed and with reed density. Breeding success measured as the probability of fledging chicks was positively influenced by reed density only and was not affected by management type, nesting height, water depth and water level fluctuation. Reed density had a central role as it mediated the effect of management both on nest site selection and breeding success, likely through better concealment of the nests from predators. Our results suggest that winter management should be favored as much as possible in the conservation of Great Reed Warblers and other reed-nesting passerines, whereas spring management should be avoided as it results in a complete lack of reed or poorly grown reed unsuitable for nest-building by the start of the breeding season. Our study draws attention to the importance of proper management of small canals that can serve as local hotspots of biodiversity in heavily human-modified landscapes, and which thus deserve more conservation attention than they currently have.

The structure of plant–pollinator networks is affected by crop type in a highly intensive agricultural landscape

In agricultural landscapes, bipartite networks formed by pollinators and the flowers they forage on, are characterised by the presence of honeybees (Apis mellifera) or crop plants. These managed species can affect the structural properties of these networks because of spatial and temporal variation in the availability of resources, and competition for these resources; for example, crop plants such as oilseed rape and sunflower produce a large number of flowers during a short blooming period. Here, we examined the structure of plant–pollinator networks in an intensive agricultural landscape, the Zone Atelier Plaine & Val de Sèvre (West of France). We compiled a six-year monitoring dataset of plant–pollinator interactions, sampling by sweep-nets along transects in the main six crop types (811 fields in total). To describe networks, we computed six metrics: connectance, nodes number, modularity, specialisation and a nestedness measure. We found that the degree distribution (number of partners per species in the network) fitted better to Fisher’s log-series rather than Power law. Strong differences between crops were observed in nestedness and specialisation, even when accounting for the effect of sample size: in oilseed rape, networks were much more nested and much less specialised than in sunflower. In addition, the link ‘honeybee–crop flower’ differed between the two mass-flowering crops. Honeybees and sunflowers appeared as specialist species in sunflower crops, interacting strongly and almost exclusively with each other, whereas they are usually considered highly generalist species. Indeed, sunflower pollination may be almost entirely driven by honeybees, conversely to oilseed rape crops, where the presence of wild bees and other insects tended to produce a more diversified network.

Floral resources,energetic value and pesticide residues in provisions collected by Osmia bicornis along a gradient of oilseed rape coverage

Pollinators in agricultural landscapes are facing global decline and the main pressures include food scarcity and pesticide usage. Intensive agricultural landscapes may provide important food resources for wild pollinators via mass flowering crops. However, these are monofloral, short-term, and may contain pesticide residues. We explored how the landscape composition with a different proportion of oilseed rape (6–65%) around Osmia bicornis nests affects floral diversity, contamination with pesticides, and energetic value of provisions collected by this species of wild bees as food for their offspring. Altogether, the bees collected pollen from 28 plant taxa (6–15 per nest) and provisions were dominated by Brassica napus (6.0–54.2%, median 44.4%, 12 nests), Quercus sp. (1.2–19.4%, median 5.2%, 12 nests), Ranunculus sp. (0.4–42.7%, median 4.7%, 12 nests), Poaceae (1.2–59.9%, median 5.8%, 11 nests) and Acer sp. (0.6–42%, median 18.0%, 8 nests). Residues of 12 pesticides were found in provisions, with acetamiprid, azoxystrobin, boscalid, and dimethoate being the most frequently detected at concentrations up to 1.2, 198.4, 16.9 and 17.8 ng/g (median 0.3, 10.6, 11.3, 4.4 ng/g), respectively. Floral diversity and energetic value of provisions, but not the Pesticide Risk Index depended on landscape structure. Moreover, pollen diversity decreased, and energetic value increased with landscape diversity. Thus, even a structurally simple landscape may provide diverse food for O. bicornis if the nest is located close to a single but resource-diverse patch. Both B. napus and non-crop pollen were correlated with pesticide concentrations.

Combining incentives with collective action to provide pollination and a bundle of ecosystem services in farmland

Bee decline and pollination deficit are driven by intensive agriculture and particularly pesticide use. So far policies to halt the decline and reduce pesticides have not unanimously been accepted, because they were not based on win-win solutions for farmers, beekeepers and biodiversity. A co-management of pests and bees is necessary, and in this study we tested if an incentive scheme based on beekeeper-farmer interdependency and collective action can lead to win-win solutions. We built a bioeconomic model to represent the mutual interdependency through pollination in intensive agricultural landscapes and simulate the economic and ecological impacts of introducing two beekeeping subsidies and one pesticide tax for different communication contexts. The model was calibrated using data from a study area in Western France. We showed that incentives affected targeted stakeholders, but also non-targeted stakeholders through a spillover effect, which therefore influenced the magnitude of ecosystem services provided at the landscape scale. We exhibited that communication between farmers and beekeepers amplified this spillover effect. Subsidies on beehives and honey led to win-win solutions for beekeepers and farmers since they had excellent pollination and economic performances, widely improved by communication. However, they were detrimental for other ecosystem services (ES) including pollination by wild pollinators. Conversely, tax on pesticides showed low economic performances, but was beneficial for the environment. Our study illustrates how a collective management of pollination is beneficial but warns against the artificialization of the pollination service that could result.

Passive monitoring of avian habitat on working lands.

Intensive agricultural landscapes are a challenge for wildlife managers, policy makers, and landowners hoping to increase the diversity of desired wildlife species, such as grassland birds, which require urgent conservation action. In intensive agricultural landscapes, like those of the midwestern USA, most land area is privately owned and operated and managed primarily for production. Conducting ecological research in intensive agricultural landscapes thus requires collaborative approaches aimed at farm owners and operators. Recent advances in acoustic data collection and high-resolution habitat mapping, including low-cost acoustic recorders and satellite remote sensing, may be well positioned to address this challenge by enabling expanded assessments and monitoring of wildlife populations and habitats across regions. This study examined fine grain habitat characteristics and their relationship with avian biodiversity in intensive agricultural landscapes at 44 agricultural sites across Iowa, USA. Passive acoustic monitoring and manual identification of bird species allowed for measurement of vocalizing bird richness. High resolution mapping of noncrop vegetation provided detailed information on small noncrop vegetation habitat complexes within row-crop agriculture. Measures of image texture provided characterizations of compositional heterogeneity within noncrop vegetation. General linear Poisson modeling demonstrated robust associations between noncrop vegetation and vocalizing bird richness, yet variation in grassland bird richness was not well predicted by noncrop vegetation. Noncrop vegetation texture demonstrated potential as a predictor of vocalizing bird richness, though not better than or when combined with noncrop vegetated area, indicating it may not be an independent measure of habitat quality. Passive acoustic monitoring resulted in useful data at 44 out of 60 originally selected sites, with some lost to failed recorders and/or collaboration issues. Challenges remain in detecting habitat characteristics that promote grassland birds in row crop landscapes. Working toward probabilistic research design across privately owned working landscapes and incorporating more detailed management practice information would improve the transferability of this approach to farmland management and policy.

Influence of prey availability on habitat selection during the non-breeding period in a resident bird of prey

BackgroundFor resident birds of prey in the temperate zone, the cold non-breeding period can have strong impacts on survival and reproduction with implications for population dynamics. Therefore, the non-breeding period should receive the same attention as other parts of the annual life cycle. Birds of prey in intensively managed agricultural areas are repeatedly confronted with unpredictable, rapid changes in their habitat due to agricultural practices such as mowing, harvesting, and ploughing. Such a dynamic landscape likely affects prey distribution and availability and may even result in changes in habitat selection of the predator throughout the annual cycle.MethodsIn the present study, we (1) quantified barn owl prey availability in different habitats across the annual cycle, (2) quantified the size and location of barn owl breeding and non-breeding home ranges using GPS-data, (3) assessed habitat selection in relation to prey availability during the non-breeding period, and (4) discussed differences in habitat selection during the non-breeding period to habitat selection during the breeding period.ResultsThe patchier prey distribution during the non-breeding period compared to the breeding period led to habitat selection towards grassland during the non-breeding period. The size of barn owl home ranges during breeding and non-breeding were similar, but there was a small shift in home range location which was more pronounced in females than males. The changes in prey availability led to a mainly grassland-oriented habitat selection during the non-breeding period. Further, our results showed the importance of biodiversity promotion areas and undisturbed field margins within the intensively managed agricultural landscape.ConclusionsWe showed that different prey availability in habitat categories can lead to changes in habitat preference between the breeding and the non-breeding period. Given these results we show how important it is to maintain and enhance structural diversity in intensive agricultural landscapes, to effectively protect birds of prey specialised on small mammals.

The Oriental turtle dove (Streptopelia orientalis Latham, 1790) (Aves: Columbidae), a new species for the avifauna of Serbia

On 13 January 2019, an individual Oriental turtle dove (Streptopelia orientalis Latham, 1790) was recorded. The species is shortly observed during tree-perching in an intensive agricultural landscape near Temerin Town, Vojvodina Province, Northern Serbia. The observed dove was a putative juvenile bird belonging to the subspecies meena. This finding represents the first observation of the Oriental turtle dove and the sixth native species from the order of Columbiformes recorded in Serbia.

The role of reed management and habitat quality on brood parasitism and chick survival of the brood parasitic Common Cuckoo.

Despite efforts on ecosystem restoration and management, biodiversity loss remains one of the major environmental concerns of our time. Beyond the focus on threatened species, animals that indicate regional biodiversity hotspots and population trends, such as brood parasites, should also be targeted by conservation actions. We studied how reed habitat quality and management influence brood parasitism rate and offspring survival in Common Cuckoos Cuculus canorus parasitizing nests of Great Reed Warblers Acrocephalus arundinaceus in six reed habitats in an intensive agricultural landscape. Data collected from 45 sites over 13 years showed that the brood parasitism rate was highest on large canals and was positively influenced by the availability of potential perches (Cuckoo vantage points) and the height where host nests were built. Cuckoo chick survival decreased with water depth and was not affected by other factors. Our results suggest that the habitat-dependent detectability of host nests was central in brood parasitism rate and that water level was central in Cuckoo chick survival. Our study shows that a maintenance of intermediate water levels is the most optimal for maintaining Cuckoo populations in intensive agricultural landscapes. Because brood parasites are excellent bioindicators as their presence predicts regional hotspots of taxonomic and functional diversity as well as population trends in bird communities, knowledge on their habitat requirements is relevant in management targeting diverse bird communities.

Citizen support for agri-environmental measures motivated by environmental consciousness

Citizens are indispensable stakeholders in rural social-ecological systems and public policies that affect them. For example, the EU’s Common Agricultural Policy (CAP) promotes agri-environmental measures (AEMs) to reduce agricultural externalities and enhance supply of ecosystem services to benefit society, compensating farmers for incurred costs and income foregone with public money. However, studies on citizen support for AEMs are rather rare. This study assesses citizen preferences for specific AEMs with a discrete choice experiment in a rural area in Flanders, which stands as an example for densely populated, intensive agricultural landscapes. Hybrid choice modelling based on the multidimensional environmental consciousness framework revealed support and significant willingness to pay for all AEMs, although with substantial heterogeneity. Mechanical weeding and increasing nesting opportunities for bees and birds were particularly favored. The affective dimension of environmental consciousness, i.e., environmental attitude, only plays a limited role in shaping the observed preferences. The cognitive dimension is even less relevant for specific preferences. This should be considered if one aims to realize community supported policies. The study presents the applicability of hybrid choice modelling in the field of environmental economics and highlights some methodological issues.

Effects of intensive agricultural landscapes on farmland use by medium and large mammals in Japan

ABSTRACT This study aimed to determine the effects of landscape differences associated with intensive agricultural activities on farmland use by medium and large mammals in Japan. We compared the species diversity of mammals that used farmland within three regions with different agricultural activity levels, and analyzed the relationship between the occurrences and escape responses of mammals in the farmland and surrounding landscape. We used spotlight count in intensive (high agricultural activity), intermediate (moderate agricultural activity), and non-intensive (low agricultural activity) areas. We observed 271 and 199 occurrences of mammals in spring and autumn 2021, respectively. Seasonal changes in mammals occurrence were due to a decrease in the number of raccoon dogs observed. Species richness tended to be lower in intensive agricultural areas than in other areas, suggesting that intensive agricultural landscapes negatively affect the community structure of medium and large mammals. Generalized additive models showed that the effects of the surrounding landscape on the occurrences and escape responses of raccoon dogs, red foxes, and cats differed among species. Only raccoon dogs were negatively affected by the surrounding farmland, suggesting high sensitivity to agricultural activities. Our results have important implications for the management of ecosystems in Japanese agricultural areas.

Vegetation height and structure drive foraging habitat selection of the lesser kestrel (Falco naumanni) in intensive agricultural landscapes.

Habitat selection in animals is a fundamental ecological process with key conservation implications. Assessing habitat selection in endangered species and populations occupying the extreme edges of their distribution range, or living in highly anthropized landscapes, may be of particular interest as it may provide hints to mechanisms promoting potential range expansions. We assessed second- and third-order foraging habitat selection in the northernmost European breeding population of the lesser kestrel (Falco naumanni), a migratory falcon of European conservation interest, by integrating results obtained from 411 direct observations with those gathered from nine GPS-tracked individuals. The study population breeds in the intensively cultivated Po Plain (northern Italy). Direct observations and GPS data coincide in showing that foraging lesser kestrels shifted their habitat preferences through the breeding cycle. They positively selected alfalfa and other non-irrigated crops during the early breeding season, while winter cereals were selected during the nestling-rearing phase. Maize was selected during the early breeding season, after sowing, but significantly avoided later. Overall, vegetation height emerged as the main predictor of foraging habitat selection, with birds preferring short vegetation, which is likely to maximise prey accessibility. Such a flexibility in foraging habitat selection according to spatio-temporal variation in the agricultural landscape determined by local crop management practices may have allowed the species to successfully thrive in one of the most intensively cultivated areas of Europe. In the southeastern Po Plain, the broad extent of hay and non-irrigated crops is possibly functioning as a surrogate habitat for the pseudo-steppe environment where most of the European breeding population is settled, fostering the northward expansion of the species in Europe. In intensive agricultural landscapes, the maintenance of alfalfa and winter cereals crops and an overall high crop heterogeneity (deriving from crop rotation) is fundamental to accommodate the ecological requirements of the species in different phases of its breeding cycle.