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Analysis of trends and agricultural drivers of farmland bird declines in North America: A review
Abstract
Globally, agriculture has intensified during the past 50 years due to increased mechanization, changes in the timing of farming operations, grassland conversion to cropland, and increased agrochemical inputs. Birds associated with farmlands and grasslands in North America have experienced severe declines over the last several decades, prompting the need for a comprehensive review of the drivers, mechanisms and magnitude of effects on bird populations. Here we evaluated changes in North American farmland bird populations over time and conducted a systematic review and analysis of the published literature to identify the major causes. Based on North American Breeding Bird Survey data, populations of 57 of 77 (74%) farmland-associated species decreased from 1966 to 2013. Multiple species exhibited highly congruent declines during the 1960s-1980s − a period with rapid changes in farming practices to low tillage systems, heavy pesticide use and widespread conversion of grassland habitat to cropland. The most severe declines occurred in aerial insectivorous birds (average change of −39.5% from 1966 to 2013), followed by grassland (‐20.8%) and shrubland (‐16.5%) bird species. Direct agricultural drivers impacting bird abundance, survival, and reproduction include loss of natural habitats, interference from farming equipment, and direct mortality or sublethal effects from pesticide exposure. Subtle interference with behaviour or physiology are reported through indirect drivers such as reduced food supplies, sublethal pesticide toxicity, habitat fragmentation and alteration, and disturbance. Indirect effects are likely significant for many species, particularly aerial insectivores, but detailed mechanistic studies are lacking. Our review of 122 studies found that pesticides (42% of all studies), followed by habitat loss or alterations (27%), were most predominant in negatively affecting farmland birds, with pesticides (93% negative) and mowing/harvesting (81% negative) having the most consistently negative effects. Modifications to farmland management such as reducing pesticide inputs through integrated pest management and maintaining or restoring uncultivated field margins and native habitat could positively influence farmland birds without significantly reducing agricultural crop yields.
... Intenzifikácia poľnohospodárskej výroby bola už mnohokrát identifikovaná ako jedna z hlavných príčin úbytku biodiverzity v európskom (Donald et al. 2006;Lichtenberg et al. 2017;Stoate et al. 2009), aj severoamerickom kontexte (Stanton, Morrissey & Clark 2018). Najnovšia metaanalýza týkajúca sa hmyzu ju dokonca dala na prvé miesto spolu s konverziou prírodných biotopov na agroekosystémy (Sánchez-Bayo & Wyckhuys 2019). ...
... Medzi najdôležitejšie prejavy intenzifikácie poľnohospodárstva patria: strata habitatov a fragmentácia krajiny; mechanizácia, priama mortalita pri poľnohospodárskych činnostiach; intenzívnejšie používanie hnojív; intenzívnejšie používanie pesticídov a ich toxicita; prechod z jarných na ozimné typy plodín -nedostatok oranísk v zimnom období, skoršie práce na poliach, na jar rýchlejší rast plodín a vysoké porasty; odvodňovanie krajiny a intenzifikácia menežmentu lúk a pasienkov (vyššie denzity dobytka, častejšie kosenie); zmeny v pestovaných plodinách a redukcia ich striedania, vypustenie úhorov a zmeny v potravnej ponuke (Chamberlain et al. 2000;Newton 2004;Stanton et al. 2018) . Zmeny v potravnej ponuke súvisia takmer so všetkými vyššie uvedenými javmi (Newton 2004). ...
... Zmeny v potravnej ponuke súvisia takmer so všetkými vyššie uvedenými javmi (Newton 2004). Niektorí autori ich preto nezaraďujú medzi ne, ale uvádzajú ich ako mechanizmus, prostredníctvom ktorého majú tieto zmeny v hospodárení vplyv na vtáky (Stanton et al. 2018). ...
Populations of insectivorous farmland birds recently underwent dramatic declines. Agricultural intensification is the main cause of these population changes, but involves numerous different mechanisms. Changes in food supply are thought to be one of the key factors. Homogenization of diet supplied to insectivorous chicks reduces their growth rate resulting in their smaller size as adults; decreased abundance of prey affects both survival and fitness of chicks and the overall breeding success. The accessibility of food is one of the most important factors limiting the use of food-rich habitats. However, the impact of all these factors on population trends has been shown in a single species – grey partridge. While the effect of changes in food supply on the breeding success has been confirmed in many other species, there is a lack of information on subsequent links to the survival of fledglings and the major causes of mortality outside the breeding period remain unclear. In general, there is insufficient information on population consequences of the changes in food supply for farmland birds, particularly in Central and Eastern Europe – the region with different characteristics from those we find in regions in which most of the findings were collected. Without this information, it is difficult to assess the specific causes of decline of individual species and then propose measures to eliminate the negative impacts of agriculture.
... Land-use change is an ongoing concern for conservation of grassland birds in the northern Great Plains of the United States. Grassland and wetland habitats in the region continue to be lost, primarily due to expansion and increased intensity of tillage agriculture, especially in the eastern portion of the northern Great Plains (Niemuth et al., 2022;Stanton et al., 2018;Wright & Wimberly, 2013). Grasslands are being converted to crop fields because of pressures caused by new cropping technologies, subsidized demand for ethanol, increased prices for agricultural commodities, genetically modified crops, changes in temperature and precipitation that enable planting of more profitable crops, and government crop subsidies (Government Accountability Office (GAO), 2007; Stephens et al., 2008;Claassen et al., 2011;Rashford et al., 2011;Lark et al., 2015;Stanton et al., 2018). ...
... Grassland and wetland habitats in the region continue to be lost, primarily due to expansion and increased intensity of tillage agriculture, especially in the eastern portion of the northern Great Plains (Niemuth et al., 2022;Stanton et al., 2018;Wright & Wimberly, 2013). Grasslands are being converted to crop fields because of pressures caused by new cropping technologies, subsidized demand for ethanol, increased prices for agricultural commodities, genetically modified crops, changes in temperature and precipitation that enable planting of more profitable crops, and government crop subsidies (Government Accountability Office (GAO), 2007; Stephens et al., 2008;Claassen et al., 2011;Rashford et al., 2011;Lark et al., 2015;Stanton et al., 2018). Because of grassland losses and other stressors, populations of grassland birds in North America were shown to have "…steeper, more consistent, and more geographically widespread declines than any other behavioral or ecological guild of North American species, including neotropical migrants" (Knopf, 1994, p. 251). ...
... Conversely, high-density quartiles for most eastern species have relatively high risk of conversion, low amounts of protected land, and high amounts of cropland and development, which might necessitate formal protection of remaining grasslands (Withey et al., 2012). Given limited knowledge of how grassland birds respond to artificial habitats and altered ecological processes created by agriculture in the Great Plains (Askins et al., 2007;Stanton et al., 2018), a cycle of research and conservation (National Ecological Assessment Team, 2006) might be necessary to develop or refine conservation strategies and site-level treatments for species inhabiting agriculture-dominated landscapes. In all landscapes, an adaptive approach to conservation strategies may be particularly important as land use and bird populations are influenced by climate change and associated uncertainties with land use and ecological processes (Grand et al., 2019;Zuckerberg et al., 2018). ...
Spatially explicit models are an important component of systematic conservation planning, enabling the depiction of biodiversity metrics across landscapes and objective evaluation of candidate sites for conservation delivery. However, sites considered “best” for conservation are typically viewed from the standpoint of biological value and may not be the most effective or efficient when risk of habitat loss, cost of conservation, intended conservation treatments, and overall conservation strategy are considered. We evaluated risk of habitat loss, land cost, and landscape context for geographic areas harboring most‐dense to least‐dense population quartiles for 16 species of grassland birds in the US northern Great Plains. Differences in land cost, risk of grassland conversion, and landscape context among quartiles and species indicated that a minimum‐area strategy may be inefficient and even ineffective. Priority zones for western species were generally associated with lower agricultural land cost, more protected land, and landscape characteristics associated with intact grasslands; eastern species were generally associated with higher agricultural land cost, tillage probability, grass loss, cropland, development, forest, Conservation Reserve Program grasslands, and distance to grass. Our results indicate that addressing areas outside of population cores increases conservation options and may provide substantial benefits to portions of populations that are most vulnerable to habitat loss or other stressors.
... In particular, range-restricted species of higher conservation concern are often disproportionately sensitive to habitat conversion and thus absent from working landscapes (Sykes et al. 2020), especially in the tropics . In temperate areas, however, many species of conservation concern are associated with diversified farms but in decline due to the replacement of diverse agroecosystems with vast, conventionallyfarmed monocultures (Donald et al. 2006;Kleijn et al. 2011;Gamero et al. 2017;Stanton et al. 2018). ...
... Species of conservation concern were more consistently present and flocking species absent on farms near more ungrazed habitat. It is unsurprising that species of conservation concern benefit from surrounding ungrazed habitat, as agricultural intensification is a major threat to North American birds (Stanton et al. 2018). In contrast, structurally complex vegetation in ungrazed habitats may deter the movement of flocking species that prefer more open habitats (Harris and Reed 2002), although we did not specifically measure structural complexity or heterogeneity. ...
... Farmland birds are in decline (Stanton et al. 2018;Rosenberg et al. 2019). Our results suggest that maintaining non-crop vegetation on farms and, even more importantly, in surrounding landscapes can result in large conservation gains, especially for species of conservation concern. ...
Context
Conservation in working landscapes is critical for halting biodiversity declines and ensuring farming system sustainability. However, concerns that wildlife may carry foodborne pathogens has created pressure on farmers to remove habitat and reduce biodiversity, undermining farmland conservation. Nonetheless, simplified farming landscapes may host bird communities that carry higher foodborne disease risks.
Objectives
We analyzed the effects of local farming practices and surrounding landscapes on bird communities and food-safety risks across 30 California lettuce farms. Specifically, we sought to determine how farmland diversification affects bird diversity, fecal contamination, and foodborne pathogen incidences, thereby identifying potential tradeoffs between managing farms for bird conservation versus food safety.
Methods
We surveyed birds at 227 point-count locations, quantified fecal contamination along 120 transects, and assayed 601 bird feces for pathogenic E. coli, Campylobacter spp., and Salmonella spp. We then used hierarchical models to quantify effects of farm management and landscape context on bird communities and food-safety risks.
Results
Surrounding ungrazed seminatural areas were associated with higher bird diversity, more species of conservation concern, and fewer flocks that may increase risks from foodborne pathogens. In contrast, on-farm diversification practices and surrounding grazing lands offered weaker bird conservation benefits. Surrounding grazed lands were associated with more potentially pathogenic bird feces in crop fields.
Conclusions
Our results suggest that habitat conservation around produce farms could support bird conservation without increasing foodborne pathogens, especially on farms further from grazing lands. Thus, interventions that diversify farming systems offer potential to simultaneously conserve biodiversity and provide safe food for human consumption.
... Regenerative agriculture can also be applied to advantage in annual crop production. 136,137 If the capacity of soils and landscapes to provide ecological goods and services is respected, smaller beneficial habitat patches are provided by conserved field edges, ponds and their borders, poorly drained areas, and slopes. 136,138 LaForge et al. reiterate that producing "the food that sustains us is one of the most significant human undertakings." ...
... 136,137 If the capacity of soils and landscapes to provide ecological goods and services is respected, smaller beneficial habitat patches are provided by conserved field edges, ponds and their borders, poorly drained areas, and slopes. 136,138 LaForge et al. reiterate that producing "the food that sustains us is one of the most significant human undertakings." 127 So is biodiversity conservation and maintaining ecosystem functions via certification in crop and livestock production, direct producer-consumer participation and many other creative ways to advance sustainability. ...
We use banding, field observations and related data to describe eagle's ecological characteristics, including nesting prey use and trends, migration routes, winter distribution and survival. For a conservation perspective we examine interdisciplinary analyses toward broad based sustainability.
... Regenerative agriculture can also be applied to advantage in annual crop production. 136,137 If the capacity of soils and landscapes to provide ecological goods and services is respected, smaller beneficial habitat patches are provided by conserved field edges, ponds and their borders, poorly drained areas, and slopes. 136,138 LaForge et al. reiterate that producing "the food that sustains us is one of the most significant human undertakings." ...
... 136,137 If the capacity of soils and landscapes to provide ecological goods and services is respected, smaller beneficial habitat patches are provided by conserved field edges, ponds and their borders, poorly drained areas, and slopes. 136,138 LaForge et al. reiterate that producing "the food that sustains us is one of the most significant human undertakings." 127 So is biodiversity conservation and maintaining ecosystem functions via certification in crop and livestock production, direct producer-consumer participation and many other creative ways to advance sustainability. ...
In this manuscript, the authors interpret the long-term trends and provide broad and interdisciplinary interpretations by incorporating new insights from eagles studied in other areas, and by reflecting on the combined local challenges of sustainability, climate change and biodiversity losses in the prairie region. These data are presented for the first time in the biological literature.
... In recent decades, agricultural landscapes worldwide have undergone major changes triggered by agricultural management and mechanisation, which have affected ecosystem functions and led to the decline of wild birds (Green et al. 2005;Inger et al. 2015;Stanton et al. 2018). Several factors, such as the reduction of food resources, the fragmentation and destruction of habitats, and the use of pesticides, are at the root of the progressive decline of farmland birds (Chiron et al. 2014;Stanton et al. 2018;Rigal et al. 2023). ...
... In recent decades, agricultural landscapes worldwide have undergone major changes triggered by agricultural management and mechanisation, which have affected ecosystem functions and led to the decline of wild birds (Green et al. 2005;Inger et al. 2015;Stanton et al. 2018). Several factors, such as the reduction of food resources, the fragmentation and destruction of habitats, and the use of pesticides, are at the root of the progressive decline of farmland birds (Chiron et al. 2014;Stanton et al. 2018;Rigal et al. 2023). The role of pesticides in this decline is undoubtedly the most debated factor. ...
Pesticide contamination is often cited as a key factor in the global decline of farmland birds. However, the majority of studies on pesticide exposure in non-target fauna are not representative of what happens in nature because they are limited to artificial conditions. The aim of this study was to define and compare, for the first time, pesticide contamination in grey partridges (Perdix perdix) from two different contexts, i.e., captivity vs. the wild. Blood samples taken from 35 captive and 54 wild partridges in 2021–2022 were analysed for 94 pesticides most commonly used in French agriculture. Captive partridges had 29 molecules detected in their blood (12 herbicides, 14 fungicides, and three insecticides) compared to wild partridges, which had 50 molecules (13 herbicides, 23 fungicides, and 14 insecticides). Of these pesticide compounds found in individuals, 26 were banned. Captive partridges had significantly fewer pesticide molecules than wild partridges, with one to 14 pesticides per captive individual and 8 to 20 pesticides per wild individual. Nineteen molecules were common to both groups, with concentrations up to three times higher in wild partridges than in captive partridges. Our results thus show multiple exposures for most of our individuals, especially in wild partridges, which can lead to cocktail effects, which are never considered. Furthermore, the difference in contamination between the wild and captive partridges reflects the multiple routes of contamination in nature, in particular, due to the use of a wide range of habitats by wild partridges.
... This suggested that land use change could result in severe species loss of natural enemies, and even diversification of agricultural landscapes couldn't bridge this gap, with ecological niches being filled by fewer species (Sekercioglu, 2012). It also implied that natural enemies may be the most sensitive avian functional group to agricultural intensification (Stanton et al., 2018;Sherry, 2021;Garrett et al., 2022). ...
... Area of agricultural land (A_CA) and mean area of agricultural land (A_AREA_MN) had significant negative effects on bird abundance, but no significant effect on species richness. Previous studies have pointed out that agricultural land expansion, accompanied by heavy use of pesticides and fertilizers, has led to a general decline in bird abundance, consistent with our results (Stanton et al., 2018;Rigal et al., 2023). However, local bird population declines may not be reflected in changes in species richness or community composition, making species richness of limited value for conservation (Hillebrand et al., 2017;Dornelas et al., 2019;Kuipers et al., 2023). ...
Agricultural expansion and intensification pose significant threats to global biodiversity. However, the conservation of agricultural biodiversity is essential for harmonizing agricultural production with ecological sustainability. Agricultural diversification can mitigate the negative impacts of agriculture on ecosystem functioning and biodiversity. Characteristics of the broader landscape may also play an important moderating role in diversified agricultural landscapes, but are not fully solved. To bridge this gap, we conducted a meta-analysis of peer-reviewed studies to compare bird abundance and species richness in diversified agricultural landscapes compared to those in simplified farmlands and natural landscapes. We also explored the moderating role of species functional groups and 11 metrics of landscape composition, configuration and heterogeneity. We found a generally positive effect of perimeter-to-area ratio of farmland patches, connectivity within farmland patches, and connectivity within patches of natural and seminatural habitats on bird abundance and species richness. Responses to other landscape metrics were less consistent. For pollinators, the abundance was higher in diversified agricultural landscapes compared to control groups, and particularly when compared to natural landscapes. For natural enemies, the species richness was significantly lower in diversified agricultural landscapes than in natural landscapes, while their abundance was not. The overall abundance and species richness of granivores and frugivores in diversified agricultural landscapes were comparable to those in control landscapes. These results indicated landscape type of control groups, species functional groups, and their interactions had consistent impacts on the responses of bird diversity. We found a vital role of farmland patch shape and connectivity within farmland and habitat patches for bird conservation in diversified agricultural landscapes, which has been rarely reported in previous studies. These insights underscore the need for policymakers and managers to develop farmland management and planning strategies at multiple scales to fulfill growing human demands while achieving biodiversity conservation objectives.
... An interesting yet expected result is the considerable variability observed among different crop types regarding their ability to maintain biodiversity (Figures 2, 4). The negative impact of agriculture on biodiversity is reinforced by intensified management (Habel et al. 2019;Tsiafouli et al. 2015), including tillage, pesticide, and fertilizer applications (Guinet et al. 2023;Shi et al. 2024;Cozim-Melges et al. 2024;Stanton, Morrissey, and Clark 2018) and eliminating vegetation or reducing plant diversity (Gordon et al. 2007;Danne et al. 2010;Liu et al. 2015). Differences in land-use intensity and farming practices result in varied threats to biodiversity (Jeanneret et al. 2021;Tang et al. 2021), due to a reduced availability of floral and nesting resources (Martins et al. 2018) and deteriorated soil properties (de Graaff et al. 2019;Franco et al. 2019;Smith et al. 2016). ...
The negative impact of agricultural land on biodiversity is widely recognized. However, there remains a knowledge gap regarding the role of different crop types in maintaining biodiversity within the agricultural landscape. By extracting biodiversity data from global datasets and classifying different crop types, we quantified the contribution of different crop types to biodiversity. Our results indicate that biodiversity levels vary widely among crop types. We found a general loss of biodiversity when natural vegetation is converted to agricultural land, and highest losses in fiber crops, cereals and oil crops, and least in other crops (such as coffee or cocoa) and in mixed crops. In general, perennial crops retain more biodiversity than annual crops. Losses of biodiversity can be mitigated through mixed cropping of multiple crop types, especially by combining annual and perennial crops. The negative impact of converting natural vegetation to agriculture is greater in tropical than in nontropical areas, and hence, the import of commodities from these biodiversity‐rich regions may be particularly detrimental. Given the ongoing increase in biodiversity losses from global intensification and expansion of agricultural land, maintaining or restoring natural vegetation, rating the crop‐type‐specific biodiversity, diversifying crops, and preferring perennial over annual crops, particularly in the tropics, need to be better considered and implemented in global agri‐environmental schemes.
... Birds of agricultural systems are one of the most threatened groups of birds in the world mainly due to their sharp population decline in recent decades (Giralt et al. 2008, Stanton et al. 2018. Many shrikes as strictly insectivorous birds are declining, and some frequently inhabit the farmland habitats. ...
... All over the world, a reduction in the biodiversity of organisms is observed in the environment, through a reduction in populations of, for example, insects, earthworms and birds [90][91][92][93]. Such disturbances in ecosystems are the result of stress factors, among which herbicide use is a huge contributor [94]. ...
One of the guiding principles of the sustainable use of herbicides is their targeted action exclusively against weeds, consisting of blocking photosynthesis and synthesis of amino acids and growth regulators. Herbicides are major elements of plant production, indispensable to the functioning of modern agriculture. Nevertheless, their influence on all elements of the natural environment needs to be continuously controlled. This review article summarizes research addressing the effects of herbicides on the natural environment and the changes they trigger therein. Herbicides, applied to protect crops against weed infestation, are usually mixtures of various active substances; hence, it is generally difficult to analyze their impact on the environment and organisms. Nonetheless, an attempt was made in this review to discuss the effects of selected herbicides on individual elements of the natural environment (water, soil, and air) and organisms (humans, animals, plants, and microorganisms). In addition, the article presents examples of the biodegradation of selected herbicides and mechanisms of their degradation by bacteria and fungi. Based on this information, it can be concluded that the uncontrolled use of herbicides has led to adverse effects on non-target organisms, as documented in the scientific literature. However, further research on the environmental effects of these chemicals is needed address the missing knowledge on this subject.
... It can therefore be expected that implementing suitable management inside rights-of-way in the aim of developing their potential functions as habitats, conduits and possibly sources for re-colonizing neighboring degraded landscapes (Burel and Baudry 1999), could yield positive impacts. Such impacts would be felt not only at the local scale but also to a broader extent by limiting and compensating for the general decline of so-called common species, such as weeds and flying insects as well as downstream beneficiaries like birds (Hallmann et al. 2017;Richner et al. 2017;Stanton et al. 2018). ...
For a number of years, the rights-of-way (ROW) of several types of linear transportation infrastructure (LTI), such as roads, railways, waterways and power lines, have been regarded as possible shelter for biodiversity, notably local flora and entomofauna. For developing an informed general management policy of such an opportunity for species conservation and landscape connectivity, a fundamental prerequisite is to be aware of the ecological shelter potential available within LTI rights-of-way on a national scale. By considering the primary operating constraints of LTIs and their geometric characteristics, a GIS-based method was designed to approximate the linear extent and surface area of potential ecological shelter (PES), i.e. where actions could be implemented to provide sustainable shelter focused on local flora and entomofauna. At the scale of Metropolitan France, the minimum total surface area of PES amounts to 2,026 km²; and its network spans over 88,094 km (39% power lines, 34% railways, 18% roads and 9% waterways). The State is the primary landowner of PES along operated networks (particularly railways) however over half of the assets (53.8%) fall under the responsibility of local authorities, concessionary companies and private landowners (notably power lines). These findings highlight the necessary involvement of State together with LTI operators, local stakeholders and landowners through partnerships aiming to implement the ecological shelter function of rights-of-way.
... This has led to homogenized, polluted and poorly diversified farmland habitats, threatening farmland biodiversity (Stoate et al., 2009). Farmlands birds (Stanton et al., 2018), insects (Sánchez-Bayo and Wyckhuys, 2019), earthworms (Blakemore, 2018) and mammals such as the common hamster Cricetus cricetus (Linnaeus, 1758) are severely declining (Surov et al., 2016). This is threatening ecosystemic services, which in turn induces projected yield reductions and is therefore a key issue regarding agricultural production and human food security (Altieri, 1999;Schauberger et al., 2018). ...
Modern production-oriented farming has led to a decline in agricultural biodiversity. In Europe, one example of concern is the common hamster Cricetus cricetus, a hibernating rodent once largely distributed in farmlands and now listed as Critically Endangered. The decline of this species is tied to a significant decrease in hamsters’ body mass at emergence from hibernation and in reproduction rate. Previous work has shown that monocultures of maize and wheat, which induce severe nutrient deficiencies, are a major cause of this phenomenon. To prevent such deficiencies, we tested in controlled conditions the effect of eight nutritive diets on hamsters’ hibernation and reproduction. Diets were selected for their nutritional content and based on farmers’ consultation. We tested three lipid-rich associations (‘oat–sunflower’, ‘potato–sunflower’ and ‘buckwheat–sunflower’), two protein-rich associations (‘maize–bean’ and ‘maize–pea’) and an intermediate association (‘wheat–soybean’), as well as ‘sprouted wheat’ and ‘sugar beet’. Hamsters fed the lipid-rich diets showed a better body condition at the end of hibernation. However, a low reproductive success was recorded in all groups, with only 17% of reproductive trials leading to birth. Nonetheless, the amount of protein ingested by the mothers before reproduction increased birth probability whilst pups’ survival to weaning was positively correlated to mothers’ body condition. Overall, our results show that hamsters need a balanced diet to ensure their ability to reproduce. Indeed, low-protein diets led to lower birth rates and low-lipid diets led to reduced body condition and subsequently low pups’ survival. The ‘wheat–soybean’ association best fulfilled hamsters’ nutritional needs. Overall, these results highlight the need to improve current farming practices to provide a more fulfilling nutritional environment for common hamsters and the farmland fauna.
... Currently it is possible to notice a development of the technologies used for in-store and logistics operations, with the aim of increasing the effectiveness and efficiency of all retail channels. Interestingly, even as the traditional food retail sector becomes more technologically advanced, there has been a parallel resurgence of farmers' markets and street markets [11]. ...
In this paper, we analyse how and to what extent the adoption of digital technologies in the food and retail sector is a driver for the pursuit of sustainability objectives, and therefore for the creation of sustainable value. The in-depth analysis of the literature presents a scenario that scarcely corresponds to the picture drawn by the empirical study. Thanks to a multiple case study on six companies, leaders in the food sector in Italy, it was possible to highlight a general immaturity of the relationship between digital technology decisions and sustainability strategies in this sector. The paper identifies possible reasons for the current state as a basis for future improvements.
... Birds are a critical component of biodiversity in farmlands (Whelan et al., 2015). They provide ecosystem services that benefit both agricultural production and natural ecosystems, are often used as ecological indicators, and include many taxa that are experiencing population decline and range reduction (Donald et al., 2001;Green et al., 2005;Stanton et al., 2018;Wu et al., 2022;Rigal et al., 2023). How farmlands are managed is critical to ensuring habitats are available for a range of avian taxa with diverse needs, and to reverse population declines. ...
Natural capital accounting can help farmers and producers meet global demands to disclose supply chain impacts on biodiversity and to reverse biodiversity declines in farmland. To date, methods have been limited in their ability to reliably represent biodiversity, especially fauna, and are typically prepared at the regional scale, not at the farm scale – the scale at which many decisions that impact habitats for species are made. We surveyed birds at 1155 sites across 50 farms (total area = 135,890 ha) in south-eastern Australia to relate site-level species richness of groups of birds to spatially discrete ecosystem condition states that are based on the structure and composition of vegetation and to develop a framework for farm-scale biodiversity accounting. Site-level species richness of bird groups was strongly related to ecosystem states. Spatially explicit models enabled calculation of the proportion of a farm that provides high-quality habitat for each bird group. This metric represents farm-level diversity and can be used to quantify a farm's impact on biodiversity and contribution to biodiversity conservation. This approach could be applied to agriculture regions within Australia and could be replicated in agricultural landscapes around the world where it is possible to establish applicable state and transition models with a reliable ‘best-on-offer’ or ‘reference’ condition state. Farm-scale accounts that incorporate biodiversity provide a robust tool for strategic farm management, rigorous environmental reporting, greater traceability through supply chains, and improved access to global sustainability markets.
... These migrations support essential ecosystem functions, including energy flow, nutrient cycling, and plant propagule dispersal [3]. However, global bird populations have significantly declined due to habitat loss, human activities, climate change, and invasive species [4][5][6][7][8][9]. Thus, monitoring bird activity is imperative. ...
Communal roosts are essential stopover sites for migratory birds. Monitoring the diurnal activity patterns of birds in communal roosts (DAPBCR) is crucial for understanding their migratory behavior and ecological needs. This information is crucial for guiding habitat conservation and management strategies and assessing the impact of environmental changes on bird populations. Traditional methods for extracting DAPBCR often rely on detecting high reflectivity factor arc features generated by birds collectively leaving or returning to communal roosts using weather radar data and deep learning target detection algorithms. However, many bird echoes do not produce these high reflectivity factor arc features, making pixel-level extraction of DAPBCR challenging. To address this, we propose a method for DAPBCR extraction based on the differences in the probability distribution function (PDF) of differential backscattering phase between birds and insects. This method first removes non-biological echoes from polarimetric weather radar data, retaining only biological echoes. By calculating the differential backscattering phase using the differential phase and system differential phase, we obtain the probability distribution function of the differential backscattering phase for biological echoes. We fit this PDF to a mixed Von-Mises distribution to obtain the PDFs for birds and insects. Using posterior probabilities for birds and insects, we estimate the bird-insect mixing ratio and further estimate the number of birds by combining the reflectivity factor and mean radar cross-section of birds. Applying the proposed method, we extracted DAPBCR data in the midsection of the Huai River Basin near Fuyang City from June to October 2021. We found that bird activity peaked in August and September. Based on normalized cumulative bird activity, we estimated the start, peak, and end times of DAPBCR to be July 6, August 19, and September 30, respectively.
... Additionally, efforts to increase agricultural production for export markets have supported widespread ecological degradation (Kissinger and Rees 2009). For example, comprehensive studies have documented increasing agrochemical inputs (Malaj et al. 2020) as a primary driver of habitat degradation (Bartzen et al. 2010;Howarth 2008;Main et al. 2014) and biodiversity declines among farmland birds (Stanton et al. 2018), insects (Forister et al. 2019;Raven and Wagner 2021), reptiles and amphibians (Lesbarrères et al. 2014). Such biodiversity declines are a part of the global anthropogenic pressures motivating scientists to call for urgent action against human-induced mass extinction (Ceballos and Ehrlich 2023). ...
Narratives inform policymaking by building consensus, stabilizing our shared beliefs, and legitimizing our assumptions (Roe 1992, 1994). This research applies narrative policy analysis to identify and compare the dominant agriculture and food (agri-food) narratives of Canadian federal government and civil society policy over time. It aims to understand and compare what narratives are driving the agri-food policy priorities of each group, with particular attention to how policy narratives address social and environmental goals. This analysis documents and confirms a Neoliberal Techno-optimist Growth Narrative as the dominant narrative in federal Canadian Agriculture and Agri-food Canada (AAFC) policy between 1986 and 2019. Over a similar period, civil society has adopted narratives that prioritize localization and democratization of the food system as well as food security. While the neoliberal priorities of market expansion and competitiveness are the focus within federal narratives, civil society concerns related to the social and environmental costs of economic efficiency, including reduced farmer livelihoods, environmental degradation, and loss of community decision-making capacity, have received marginal attention from federal policy. We discuss how the Neoliberal Techno-optimist Growth Narrative imposes structural barriers on the pursuit of environmental and social goals by establishing a hierarchy of goals whereby environmental/social goals can only be pursued to the extent that they contribute to economic growth and by promoting a techno-optimist approach. As such, the dominant Neoliberal Techno-optimist Growth Narrative stabilizes two contested assumptions: (1) economic growth through liberalized trade is the best approach to achieve societal wellbeing, and (2) that technological innovation will sufficiently address environmental pressures.
... Les pesticides chimiques se sont révélés toxiques pour l'homme et les animaux (Carson, 1962 ;Nicolopoulou-Stamati et al., 2016), et de récentes études rapportent des effets conséquents sur la biodiversité (Köhler et Triebskorn, 2013). Par exemple, une dégradation mondiale de la biodiversité des insectes a été observée, avec une diminution de 75 % de leur biomasse totale en Europe centrale sur une période de vingt-sept ans (Hallmann et al., 2017), conduisant à un nouveau « silent spring » (Inger et al., 2015 ;Stanton et al., 2018). Les pesticides peuvent également se révéler nocifs et causer des dommages sur des organismes non-cibles comme les pollinisateurs (Potts et al., 2021) ou les ennemis naturels, agents de biocontrôle, ce qui a souvent pour conséquence involontaire soit d'exacerber les problèmes de ravageurs existants, soit d'entraîner l'émergence de nouveaux ravageurs (Krishna et al., 2003). ...
... Many factors influence the relative abundance and trends in bird populations, and they act and interact to induce spatial patterns across a range of spatial scales (Morrison et al. 2010). Factors such as habitat change (Stanton et al. 2018, Betts et al. 2022, biotic factors like prey availability (Drever et al. 2018), or broad-scale patterns in abiotic factors like precipitation, temperature, and phenology (Renfrew et al. 2013, Wilson et al. 2018 can induce spatial patterns in trends or relative abundance and can act across different periods in the species' annual cycles (Morrison et al. 2010, Wilson et al. 2011. Likewise, conservation actions occur at many scales, from the broad scales of international conventions to the fine scales of an individual wetland (Prairie Habitat Joint Venture 2020). ...
... Lo antes mencionado y la correlación negativa entre la riqueza de las aves de pastizal con el IPPN sugiere que durante el auge ganadero entre 1965 y 1981, se desencadenó un efecto que favoreció en algunos sitios la presencia de pastos no nativos, mientras que para las aves sucedió lo contrario. Esto coincide con lo observado en los pastizales centrales de EUA, donde la disminución de la diversidad de aves de tierras de cultivo se correlacionó con cambios significativos en las prácticas agrícolas entre 1966 y 1980 (Stanton et al., 2018). Además, por monitoreos estandarizados en gradientes de pastizal nativo en EUA (Wiens, 1973), se sabe que el grupo de aves de pastizal presentó la mayor pérdida poblacional atribuible al incremento de la agricultura y la urbanización en zonas de pastizal desde la década de 1970 (Rosenberg et al., 2019). ...
Evaluamos la diversidad de pastos nativos, pastos no nativos y aves de pastizal en el Desierto Chihuahuense en un contexto histórico-ambiental de presión antropogénica en los periodos de 1930-1964, 1965-1981 y 1982-2019. Analizamos la riqueza regional, la diversidad beta y la composición de 41 especies de aves de pastizal, 149 especies de pastos nativos y 60 especies de pastos no nativos, así como la prevalencia de pastos nativos y su correlación con las aves de pastizal en cada periodo. Los resultados mostraron una reducción de la diversidad beta en los 3 ensambles a lo largo del tiempo, sin relaciones significativas entre el ensamble de aves y la prevalencia de pastos nativos en el último periodo. Esto sugiere que la distribución actual de las aves de pastizal es independiente del tipo de pasto a nivel regional. La expansión de pastos no nativos en el Desierto Chihuahuense, favorecida por políticas públicas a lo largo del tiempo, ha conformado un ensamble de pastizales mixtos, lo que actualmente no afecta la composición de aves de pastizal a escala regional. Sugerimos realizar evaluaciones locales para comprender mejor la relación entre las aves de pastizal y los distintos pastos presentes en la región.
... Their presence suggests that they mainly forage rather than reproduce in these settings. These species contribute to biotic homogenization, potentially impacting ecosystem services [66,67]. Further research is needed to evaluate the extent of biotic homogenization, especially with vineyard expansion [23]. ...
Agricultural landscapes significantly impact biodiversity, particularly within vineyard ecosystems where the configuration of native vegetation and vineyard edges plays a pivotal role. This study investigated the structure of bird communities across vineyards, their edges, and adjacent native vegetation, utilizing generalized linear mixed models to analyze the influence of surrounding land covers at varying scales of 100 m and 1000 m radii across these three landscape types on bird richness and abundance and functional groups. The results highlight that native vegetation is crucial for supporting endemic bird species, with 41% of all observed species found across all three habitat types and a significant 66.7% shared between native vegetation and edge habitats. In particular, insectivores and carnivores, key to biodiversity conservation and ecosystem service provision, showed higher abundances in areas with extensive native vegetation, underscoring its vital role in maintaining ecological functions. Edges not only enhanced the general bird richness and abundance but also served as crucial habitats for granivores and omnivores, influencing ecosystem dynamics through changes in the trophic guild community structure. These findings underscore the importance of conserving native vegetation within vineyard landscapes to foster a diverse avian community that contributes to enhancing ecosystem services. These results provide an opportunity to intensify restoration initiatives on vineyard edges and enhance our understanding of how certain species adapt to agriculture. This can be considered a vital nature-based solution for sustainable agriculture, promoting biodiversity conservation alongside productive agroecological practices in vineyard ecosystems.
... Habitat loss and degradation is also a major cause of bird decline. Urban sprawl, deforestation, intensive agriculture, and other human activities have reduced and fragmented natural bird habitats (Marzluff and Ewing 2008;McKee et al. 2013;Stanton et al. 2018;Virkkala 2016). ...
Species’ declines are caused by a combination of factors that affect survival and/or breeding success. We studied the effects of a set of environmental and anthropogenic variables on the disappearance of Canarian Houbara Bustards Chlamydotis undulata fuertaventurae on Fuerteventura (Canary Islands), once the main stronghold of this endangered bird. Of 83 male display sites detected in 1997–1998, only 29 remained occupied in 2020–2021 (a 65% decrease in only 23 years). We compared habitat quality, density of conspecifics, other steppe birds and crows, presence of human infrastructure, and degree of environmental protection between these 29 extant sites and the 54 extinct sites using univariate analyses and generalised linear models (GLMs). The most influential variable in the abandonment of display sites was the Normalised Difference Vegetation Index (NDVI), an indicator of green vegetation productivity, which suggests a strong effect of habitat aridification due to climate change on the population’s extinction process. Powerline density was the second most important factor. This suggests that houbaras have survived where a greater abundance of food resources has enabled a higher breeding success, and where powerline fatalities have caused lower mortality over the years. Higher densities of houbaras, and other steppe birds and crows at extant display sites confirmed the better habitat quality in these areas. Extant display sites, located generally in protected areas, also had lower densities of human infrastructure (e.g. buildings, roads). We discuss the conservation implications of these results and provide management recommendations for this endangered subspecies.
... One of the most studied taxa in this context is "farmland birds" and recent declines for many species in this group has been linked to intensified agricultural practices (Donald et al. 2001;Gaüzère et al. 2020;Heldbjerg et al. 2018;Jerrentrup et al. 2017;Rigal et al. 2023). Ultimate drivers of these declines seem to involve habitat loss, deteriorating food supply, and increased predation risk (Evans 2004;Stanton et al. 2018). ...
As a result of increasingly intensified agricultural practices in Europe over the last century, agroecosystems have experienced severe biodiversity declines. Among the species experiencing negative population trajectories in agricultural habitats are meadow and farmland birds, which have suffered a loss in both habitat and food availability in cultivated fields. In Denmark, biotope plans (a requirement to establish small agro-environmental habitats on properties with stocking of game birds) have been implemented as a measure to mitigate biodiversity declines in the agricultural landscape and, in this paper, we investigate to what extent these initiatives fulfil the intended purpose with respect to birds in the breeding season. We demonstrate that some initiatives like hedgerows, areas of open vegetation, scrub, and lakes seemed to increase avian diversity locally, but also that other measures such as vegetation strips, grass strips, and bare soil strips had little effect given the current implementation of these initiatives. Benefitting species were mostly scrub- and woodland species that now inhabited previously open landscapes after the establishment of suitable habitats, and the initiatives failed to show clear positive effects on meadow birds and farmland birds for which they were originally intended. The most commonly registered species in our data set was (released) Pheasant Phasianus colchicus , which emphasised that the stocking of game birds can have a clear effect on avian species composition in areas where this practice is exercised. Future studies are needed to clarify how this stocking may affect local biodiversity of different taxonomic groups.
... Farmland birds, and steppe-birds in particular, are declining at alarming rates worldwide [1][2][3]. The Iberian Peninsula represents an important European stronghold for numerous steppe birds [4][5][6], where farming intensification has led to significant population declines (e.g., [6,7]), and the recent expansion of renewable energy production infrastructures poses new threats [8][9][10]. ...
Background
Modern biologging technologies allow researchers to gain a better understanding of animal movements, offering opportunities to measure survival and remotely study the breeding success of wild birds, i.e., by locating nests. This is particularly useful for species whose nests are difficult to find or access, or when disturbances can impact the breeding outcome. We developed and validated, with field data, a framework to detect nesting events by two sandgrouse species, the black-bellied (Pterocles orientalis) and pin-tailed sandgrouse (Pterocles alchata), using GPS and Overall Dynamic Body Acceleration (ODBA) data. Sandgrouses are ground-nesting, cryptic, and elusive birds with biparental incubation efforts. Because both sexes take turns to incubate, a novel framework considering when tagged individuals are on incubation duty or not needs to be designed to detect nests.
Results
We tagged 52 birds with high-resolution GPS devices to monitor their breeding during 2021–24. Using remote tracking and field data from the first 2 years (2021–22), we first determined sex-specific time windows for incubation to maximise differentiation between incubation and non-incubation behaviours. We then used a threshold-based classification to identify incubation days and inferred the minimum number of successive incubation days needed to correctly identify a nesting event. We show how ODBA and GPS data can be used to successfully detect nests incubated for only 2 or 3 days. GPS-only data or combined GPS-ODBA data had a success rate of around 95%, whereas ODBA-only data had a success rate of 100%. Cross-validation using data from 2023 to 2024 confirmed the model’s performance, showing an overall success > 90% for GPS-only and ODBA-only data and of 85% for combined GPS–ODBA data.
Conclusions
By accurately identifying nesting events, our framework offers new opportunities to study the breeding of conservation-dependent species. Besides its applicability to ground-nesting species with biparental care and sex-specific incubation schedules, the framework can be adapted to other bird species sensitive to disturbances or with inaccessible nesting sites. By doing so, it reduces the need for nest visits and associated disturbances, as well as the carbon footprint and expenses associated with fieldwork.
... In agroecosystems, the intensification of agriculture has led to landscape homogenisation and increasing mechanisation and chemical inputs (Matson et al., 1997;Stanton et al., 2018). Among chemical inputs, pesticides are applied to prevent and control pests and weeds that may cause diseases or compete with crop plants, and include herbicides, fungicides, insecticides and rodenticides. ...
Intensive use of synthetic pesticides in conventional agriculture may harm non-target organisms through sublethal effects on life-history traits. Farmland birds are exposed throughout their life cycle, but the fate of non-persistent pesticide mixtures in wild birds remains unknown. In this study, we investigated changes in pesticide contamination levels in Montagu’s harrier (Circus pygargus) nestlings during their growth. In total, 35 chicks were sampled twice during the rearing period, and blood was tested for 116 pesticides to assess pesticide load through two proxies; the number of pesticides detected and the sum of pesticide concentrations. Body mass and tarsus length were also measured to estimate body condition. Across the two sampling times, nine herbicides, five insecticides and four fungicides were detected. Contamination levels decreased significantly with nestling age irrespective of sampling date, and there was no relationship between pesticide load and body condition. Moreover, concentrations of chlorpyrifos-methyl, fenpropidin, metamitron, picloram and S-metolachlor, all detected throughout the rearing period, were unrelated to any of the explanatory variables. However, ethofumesate concentrations decreased significantly with chick age. This study provides the first evidence that non-persistent pesticide mixtures can decrease with age in wild nestlings. This has implications for understanding how chicks are contaminated and provides new insights on pesticide fate within organisms.
... In Europe, there is a trend of declining breeding bird populations, particularly insectivorous species [6], due to various factors [74], including the use of pesticides [52]. Within photovoltaic SPP, higher numbers and species diversity of birds have been recorded compared to control plots in other agricultural lands (pastures, arable lands): 353 detections across 41 species, compared to 271 detections across 40 species. ...
Renewable energy sources, particularly solar power plants, have been increasingly widespread in recent decades. Due to the significant decrease in the cost of solar panels over the past twenty years, a rise in the number of photovoltaic installations is expected. This will lead to the formation and spread of a new type of anthropogenically transformed landscapes. Over the last decade, studies have been published evaluating the impact of solar power plants on soil cover, vegetation, wildlife, and specifically, bird fauna. These studies primarily focus on mortality factors, forecasting bird mortality as the total capacity and area of photovoltaic installations increase. Researchers conclude that the available data is insufficient to fully understand the complex interactions between the abiotic and biotic components of this new habitat. However, it is already well-established that bird mortality at solar energy facilities is the lowest compared to fossil fuel-based plants and other renewable energy sources. Some findings even suggest that photovoltaic installations may have a positive impact on biodiversity compared to other technogenically altered landscapes. Studies have documented various mechanisms through which solar power plants can affect bird populations. The physical presence of solar panels may disrupt flight routes and nesting sites. However, it is also noted that the reflective surfaces of photovoltaic panels can attract insects, which in turn provide new feeding opportunities for certain bird species. This paper aims to summarize the current global experience in assessing the impact of solar power plants on birds.
... Farmland bird populations have declined drastically in many countries due to agricultural intensification and land use changes that cause or exacerbate habitat loss, lack of food resources and high predation rates (Donald et al. 2001;Robinson and Sutherland 2002;Stanton et al. 2018). Ground-nesting farmland birds are particularly severely affected (Kamp et al. 2021). ...
High predation rates threaten many ground-nesting farmland birds and are difficult to address through conventional measures such as lethal predator control or fencing. Landscape-based approaches for conservation measures promise an alternative by reducing predator - bird encounters, but require detailed knowledge of landscape effects on predation risk. Different habitat elements attractive to predators could have opposing effects on neighbouring nesting habitats, with implications for conservation: Increased predation risk due to higher predator activity (A) or reduced predation risk by distracting predators (B). Here we focus on the placement of conservation measures using flower blocks targeted at Grey Partridges in a Central European Farmland. Based on a three-year camera trap dataset, we investigated effects of landscape structure and composition on mammalian predator activity within flower blocks at two scales (100 m and 500 m radius around the camera) with generalized linear mixed models. Length of linear edge structures, i.e., field block borders, was most important, with a greater availability of linear edge structures leading to a decrease in predator activity at both scales (hypothesis B). Conversely, predator captures at both scales increased with increasing extensive vegetation area (i.e., permanent grassland, flower blocks and fallows) and in proximity to roads, indicating that these may attract predators and increase predator densities (hypothesis A). Our results suggest that a landscape-based approach can mitigate predation risk for ground-nesting birds in flower blocks and analogous conservation measures. Highly structured, small-scale agricultural landscapes seem to be particularly important for reducing mammalian predator activity in flower blocks.
... Our results suggest that this must have resulted in a significant decline in availability of arthropod food for farmland birds. At the same time, reduced prey availability has been described as one of the drivers of farmland birds decline, since it may compromise chick survival during the breeding season (Stanton et al., 2018). Moreover, our findings indicate that arthropods are predominantly driven by food availability (living and dead plant biomass), while disturbances caused by management (herbicides, fungicides, fertilizers, cultivation) are less important. ...
The intensification of agriculture has been identified as one of the main causes of arthropod declines. To halt the decline of arthropods, changes in farming practices and management of surrounding habitats may therefore be needed. A key challenge is to identify which changes in management approaches are most effective in restoring biodiversity. Therefore, this study examines arthropod abundance and diversity in different agricultural and semi-natural habitats, and among different management types. Arthropods were sampled three times in spring and summer of 2022 and 2023 with emergence traps in 128 unique sites in an intensively farmed area in Western Netherlands. These sites included a variety of crops as well as semi-natural habitats. Our study showed that on average the abundance and diversity of arthropods of several taxa was lower in crop habitats compared to semi-natural habitats. However, these effects strongly varied among crop species. For instance, alfalfa, spelt, spring and winter wheat fields (that often had a high plant cover) supported similar arthropod diversity and abundance levels as semi-natural habitats. Interestingly, in crop fields most variables related to field management, such as herbicide applications or amount of nitrogen fertilizers, did not show any significant relationship with arthropod abundances or diversity. The number of days after cultivation was an exception, and was positively related to total arthropod abundance, Hymenoptera and Collembola abundances, and Coleoptera family diversity. Within semi-natural habitats, number of days after mowing was positively related to total arthropod abundance, Diptera, Hemiptera and Hymenoptera abundances, and Hemiptera family diversity. Additionally, plant cover was positively related to total arthropod abundance. Overall, our findings suggest that crop species and management practices that increase plant cover in spring and early summer are increasing arthropod abundance and, to a lesser extent, higher-taxa diversity in intensively farmed agricultural landscapes.
... The substantial global environmental impacts of industrial agriculture contribute to the increasing complexity of environmental management (Good and Beatty 2011;Kanter 2018;Stanton et al. 2018;USEPA 2017). As a large majority of the world's freshwater is used for agriculture (FAO 2019), the urgency of degrading environmental conditions and the complexity of management decisions in agricultural watersheds is driving the need for more participatory approaches inclusive of a wide range of stakeholders, including agricultural producers (farmers), to inform management actions Kliskey et al. 2021). ...
The vast majority of the Earth's freshwater is allocated for agricultural purposes, playing a significant role in environmental deterioration observed globally. Environmental policymakers must collaborate with agricultural producers to foster sustainable production while allowing producers to remain profitable to feed the growing world population. This study aimed to identify factors that influenced how those involved in environmental policy including regulatory agency personnel, scientists, industry representatives, and Extension specialists relate to producers about their use of agricultural technology and management practices after competing in a real-life farm management competition grounded in gamification along with adult, experiential, and peer learning. We used exploratory regression analysis to identify significant relationships between variables from the literature that suggest that the program can influence how non-producer participants relate to producers. Social norms, perceived behavioral control, peer interaction, expectations of the program, educational components of the program, risk reduction, and education level of participants were significantly related to how non-producers relate to producers about their use of agriculture technology. Social norms, peer interaction, expectations of the program, educational components of the program, and risk reduction were significantly related to how non-producers relate to producers about agricultural management practices. This study demonstrates that innovative Extension and educational programs framed in farm management competitions grounded in gamification along with adult, experiential, and peer learning are an effective way to help policymakers be more comfortable interacting with producers—a solid starting place for successful collaborations.
... We show how the expansion of intense livestock grazing systems increased the demand for fodder crops, whose early harvest leads to an ecological trap preventing any breeding outputs. The conservation problem evidenced here for the Montagu's harrier is likely transferable to other ground-nesting farmland birds in agricultural landscapes under comparable shifts, not only in Europe (e.g., great and little bustards, red-legged partridge Alectoris rufa, and several species of larks; Faria et al., 2016) but also in other continents (e.g., Stanton et al., 2018). ...
Extensive farmland in Europe hosts high biodiversity levels but is threatened by land use changes associated with market and agricultural policy drivers. We show that a nationwide replacement of rainfed cereals in favor of beef production in Portugal has coincided with a nearly 80% decline in the population of a ground‐nesting raptor, the Montagu's harrier Circus pygargus, since 2002. Reduced cereal crop cover led to nesting attempts occurring mostly in fodder crops, the predominant habitat with suitable sward structure at the onset of breeding. This results in a twofold ecological trap: early hay harvesting destroys first nesting attempts, whereas late cereal harvesting destroys replacement clutches. This double phenological mismatch prevents any breeding success and likely explains the country's observed population decline of Montagu's harriers and other key farmland birds. Reforming current agroenvironmental schemes to promote practices compatible with wild population phenology is paramount to revert these changes.
... Insecticides reduced the number of chick-food insects directly. This reduction in chickfood led to the starvation of partridge chicks as they are heavily dependent on insect availability in a narrow time window, as are many chicks of other farmland birds [14,15,[59][60][61][62]. Various mitigation measures to overcome these direct and indirect effects were developed and evaluated. ...
Background
Biodiversity loss is particularly pronounced in agroecosystems. Agricultural fields cover about one-third of the European Union and are crucial habitats for many species. At the same time, agricultural fields receive the highest pesticide input in European landscapes. Non-target species, including plants and arthropods, closely related to targeted pests, are directly affected by pesticides. Direct effects on these lower trophic levels cascade through the food web, resulting in indirect effects via the loss of food and habitat for subsequent trophic levels. The overarching goals of the European pesticide legislation require governments to sufficiently consider direct and indirect effects on plants and arthropods when authorising pesticides. This publication provides an overview of a workshop's findings in 2023 on whether the current pesticide risk assessment adequately addresses these requirements.
Results
Effects due to in-field exposure to pesticides are currently not assessed for plants and inadequately assessed for arthropods, resulting in an impairment of the food web support and biodiversity. Deficiencies lie within the risk assessment, as defined in the terrestrial guidance document from 2002. To overcome this problem, we introduce a two-step assessment method feasible for risk assessors, that is to determine (i) whether a pesticide product might have severe impacts on plants or arthropods and (ii) whether these effects extend to a broad taxonomic spectrum. When each step is fulfilled, it can be concluded that the in-field exposure of the pesticide use under assessment could lead to unacceptable direct effects on non-target species in-field and thus subsequent indirect effects on the food web. While our primary focus is to improve risk assessment methodologies, it is crucial to note that risk mitigation measures, such as conservation headlands, exist in cases where risks from in-field exposure have been identified.
Conclusions
We advocate that direct and indirect effects caused by in-field exposure to pesticides need to be adequately included in the risk assessment and risk management as soon as possible. To achieve this, we provide recommendations for the authorities including an evaluation method. Implementing this method would address a major deficiency in the current in-field pesticide risk assessment and ensure better protection of biodiversity.
... However, inherent in most agricultural practices in the tropics is a decrease in the diversity and abundance of native species, given that even the most sustainable or regenerative agricultural practices can supplement but not completely replace the resources and conditions that species need and evolved with (Quinn et al., 2014;Kross et al., 2018;Evers et al., 2018). Agriculture also often generates novel, disturbed habitats that are more easily exploited by non-native or generalist species, which can often harm native species (Stanton et al., 2018;Sandoval, 2019;Olimpi et al., 2020). Other impacts of agricultural lands related to human disturbance can also have detrimental effects on species abundance, such as noise pollution from humans or farm equipment (Reijnen et al., 1996;Francis et al., 2012;Sańchez et al., 2022). ...
Agriculture, which is spreading rapidly, is one of the major effectors on biodiversity – generally contributing to its decline. In the past few decades, most research efforts have focused on the impact of industrial agriculture on the environment and biodiversity. However, less attention has been paid on examining the impact of sustainable agricultural management practices on biodiversity. Challenges include the disruptive nature of some practices (e.g., agrochemical application) and the timing of others (e.g., tree pruning). Here, we highlight the value of passive acoustic monitoring in assessing the impact of agricultural management practices on biodiversity, using birds as indicators. We outline key considerations, including bird ecology and behavior, ARU sampling protocols, and data management. To demonstrate our approach, we present a case study from a coffee landscape in Costa Rica, where we analyzed the effects of pruning and pesticide application over two years. By focusing on selected focal species and using a subsample of the total hours recorded in combination with a mobile app for annotations, we found that pruning negatively impacted most species, while pesticide application adversely affected all species studied. Our methodology leverages technology to evaluate the impacts of agricultural management practices, offering insights to guide and assess sustainable agricultural strategies aimed at balancing biodiversity conservation with human well-being.
... This loss of biomass, and resulting loss of biodiversity, may result in reduced ecosystem services (Arnold et al., 2021), including some that benefit crop production, such as pollination (Wratten et al., 2012) and natural pest control (Knapp andŘezáč, 2015;Rusch et al., 2016;Thomson and Hoffmann, 2010). Moreover, terrestrial invertebrates are a critical component in the diet of farmland birds (Wilson et al., 1999), which are experiencing widespread declines in both Europe and North America (Donald et al., 2001b;Stanton et al., 2018). ...
Terrestrial invertebrates provide essential ecosystem services, and there is concern that their contribution could be compromised by population declines due to agricultural intensification, including pesticide use. Identifying alternative and beneficial agricultural land management measures could stem or reverse biodiversity loss. Here we examine morphospecies composition and abundance of terrestrial invertebrates sampled with pitfall traps and sweep nets in fields and field margins in the Prairie Pothole Region, Canada, close to focal wetlands on 43 sites representing four land management types. These were: conventional, minimum tillage, organic, and perennial cover. We estimate diversity at local and regional scales (alpha, beta, gamma) and examine the impacts of land management in interaction with landscape context on these descriptors of local and landscape biodiversity. We found that: 1) alpha morphospecies richness (hereafter 'alpha richness') was greater at conventionally-managed sites when they were surrounded by more grassland; 2) alpha richness differed among land management types for field locations, but not field margin locations (and also tended to be lower in fields than field margins, especially for sweep net samples); 3) species composition differed somewhat between sites managed for perennial cover versus the remaining three land management types; and 4) conventional sites had the lowest gamma evenness. Our results suggest that increasing the amount of grassland in landscapes could lessen the impact of conventional agriculture and that field margins in intensively managed farming systems are important for invertebrate diversity in this region. Maintaining natural and seminatural cover in agroecosystems, in addition to low-intensity farming practices, could sustain invertebrate biodiversity and facilitate important ecosystem services.
... The practices that intensify agriculture at a landscape scale include farming specialization on one or few crops, destruction of edge habitats, reallocation of land to increase field size, among others. At a local scale, shortening crop rotation cycles, increasing pesticide inputs, implementing genetically modified crops and increasing the size of plots are some of the practices that increase agricultural intensification (Gomez et al. 2018;Stanton et al. 2018). Benton et al. (2003) argue that while the factors leading to biodiversity loss are multivariate, landscape simplification in particular (caused by loss of heterogeneity) is a universal consequence of agricultural intensification. ...
Among human activities agriculture is one of the main drivers of biodiversity loss worldwide in recent decades. The effects of agricultural intensification on vertebrate populations may vary depending on their habitat requirements. The effect of environmental and/or genetic stress on populations can be assessed using fluctuating asymmetry and body condition of animals. We implemented both linear and geometric morphometric methods to assess the influence of agricultural intensification on three native rodent species. For this, we evaluated different stress indicators on skulls and mandibles (fluctuating asymmetry, centroid size and scaled mass index) of three species of small mammals at borders of rural roads in agroecosystems in central Argentina. We explored the impact of intensification using variables at different scales: landscape level, assessing complexity through functional and structural heterogeneity; and local level, through vegetal volume of the border. We found species-specific responses, where the most sensitive species was Calomys venustus, which showed individuals with lower developmental stability and body condition in simple landscapes and low-quality habitats. Akodon azarae responded in an intermediate manner to both size and mass index indicators, while the species Calomys musculinus was the least affected, with changes only in body condition observed, with larger individuals in more complex landscapes. Our results suggest that the impact of agricultural intensification on small mammals varies according to their habitat requirements and the landscape heterogeneity. This study shows the importance of considering both local and landscape variables to propose management measures for biodiversity conservation in cropland anthromes.
... Los productores han reconocido otros factores como causantes de cambio en la presencia de las aves de esta zona en el tiempo, los cuales también han sido destacados en otras investigaciones, teniendo en cuenta que aunque muchas especies dependen cada vez más de paisajes agrícolas gestionados por humanos, la expansión agrícola amenaza la biodiversidad a través de la fragmentación del paisaje (Hanski, 2013), la liberación de contaminantes (Bai et al., 2022) y la intensificación de las prácticas agrícolas (Stanton et al., 2018). ...
En el Distrito Regional de Manejo Integrado Cuchilla del San Juan, localizado en el municipio de Belén de Umbría, departamento de Risaralda, se documentó el conocimiento de los productores de café sobre las aves presentes en su territorio; para este propósito se desarrolló un taller con 12 caficultores con el fin de analizar el reconocimiento local de las diferentes especies de aves, su presencia en los últimos años, los beneficios y el valor cultural y biológico de los servicios ecosistémicos asociados. Los productores reconocieron 72 especies diurnas y nocturnas, pertenecientes a 15 órdenes distribuidas en 14 familias las cuales se clasificaron en 8 grupos funcionales, dentro de los cuales se resalta el grupo de las aves (IF) insectívoras/frugívoras como el más numeroso con 25 especies, seguido de las (I) insectívoras que cuenta con 20 especies, posteriormente se definieron los grupos funcionales de las aves (F) frugívoras y (G) granívoras, cada uno con 7 especies, de allí le siguieron las (NI) nectarívoras/insectívoras con 6 especies, las (C) carnívoras 5 especies y por último se encuentran los grupos de las (NE) necrófagas y (P) piscívoras, cada uno con una especie. Adicionalmente se identificaron y priorizaron algunas causas que las han afectado a través del tiempo. Los servicios ecosistémicos más valorados por los productores son los de regulación, siendo el control de insectos plaga percibido como el de mayor importancia. De otro lado, se encontró que el incremento en el uso de agroquímicos ha sido un factor determinante en la afectación sobre la presencia de aves en la zona, especialmente en el período 2000 a 2010. Estos resultados permiten establecer que la avifauna provee información sobre la calidad de los agroecosistemas evaluados e incluso sobre aquellos beneficios de la naturaleza que los productores consideran más prioritarios.
... Although increased local land use intensity resulted in an equal change in species and functional composition, predominantly by reducing species diversity, our results suggested a positive effect of nearby woody vegetation such as single trees and hedgerows, maintaining ecological function. This supports the general call to enhance landscape heterogeneity (Stanton et al., 2018) by incorporating structural landscape elements such as hedges, paddock trees, or live fence to benefit the overall bird diversity (Concepción et al., 2015) and ecosystem service provisioning (e.g., Smith et al., 2022) and to counteract biotic homogenization (Gámez-Virués et al., 2015) within agricultural areas. However, we emphasize that focusing conservation efforts in grasslands only on increasing bird species diversity could neglect ecological requirements of open grassland specialists such as the European lapwing (Vanellus vanellus), the Eurasian skylark (Alauda arvensis), and yellow wagtail (Motacilla flava), which are all exclusive ground-nesting birds that prefer open landscapes (Borges et al., 2017;Püttmanns et al., 2021;Buschmann et al., 2023) and, thus, are directly affected by management applications (e.g., mowing and fertilizing), which often temporally overlap with their breeding times. ...
In modified production landscapes, biodiversity faces unprecedented pressures from human actions, resulting in significant species declines of plant and animal taxa, including birds. Understanding the underlying mechanisms responsible for such declines is essential to counteract further loss and support practitioners in conserving biodiversity and associated ecosystem function. In this study, we used standardized bird monitoring data collected over 6 years in managed forest and grassland areas across different regions in Germany, Central Europe. We combined these data with morphometric, ecological, behavioral, and acoustic trait data and detailed information on local land use management practices to understand how management decisions affect species and functional diversity, as well as ecological processes shaping local species composition. Our results reveal that the ecosystem and regional context must be considered to understand how management practices affect bird diversity aspects and composition. In forests, regional management decisions related to tree species and stand age affected bird diversity, as well as community and functional composition, and indicated environmental sorting due to ecological and behavioral requirements, biotic interactions, and morphometric constraints. In grasslands, independent of local management practices, increased intensity of land use resulted in an overall loss in bird species richness and functional diversity. Predominantly, constraints due to ecological or behavioral requirements affected bird species assemblage composition. In addition, our results indicated the importance of woody vegetation near managed grasslands and of considering environmental conditions beyond the local scale to support bird diversity and associated ecosystem functions. Our results highlighted that local management decisions can support bird diversity and maintain ecological function. However, this needs a view beyond the local scale of management units. It also demands a joint effort of biologists and land managers to integrate targeted conservation actions into regional management practices and create a network of habitats within production landscapes to protect nature, guard against biotic and functional homogenization, and prevent further degradation of ecosystems in production landscapes.
... Biodiversity loss can have many causes and it may take place not only in agricultural landscapes (Bright et al., 2008;Stanton et al., 2018;Sylva et al., 2019;FAO, 2020;Raven and Wagner, 2021), but also inside nature conservation areas (Dirso and Raven, 2003;Hallmann et al., 2017;Goulson, 2019;Lima et al., 2020;Barendregt et al., 2022). Various reasons for this biodiversity loss have been identified, e.g., climate change (Habibullah et al., 2022;Mantyka-Pringle et al., 2012), nitrogen deposition (Bobbink et al., 2010), habitat fragmentation (Mantyka-Pringle et al., 2012), forest destruction, overfishing, invasive species, poaching, armed conflicts (Hanson et al., 2009), corruption and low income of nearby residents, who are forced to use resources of nature reserves . ...
... In the past, Europe was heavily influenced by agriculture, which led to a high level of biodiversity that was essentially a product of various management forms and measures (Billeter et al. 2008). Today, farmland biodiversity is rapidly declining worldwide (Green et al. 2005;Stanton et al. 2018). Agricultural intensification has resulted in a substantial reduction in management techniques and heterogeneity of farmland, with a concomitant loss of farmland birds (Benton et al. 2003;Donald et al. 2001;Šálek et al. 2021), and an even more dramatic decline in insects, which are the main food source for insectivorous birds (Benton et al. 2002;Raven and Wagner 2021). ...
Landscape changes and the intensification of agriculture in recent centuries were largely responsible for the dramatic decline in the biodiversity of farmlands. Rural settlements have also been subject to radical changes due to modernisation, but their impact on bird populations is poorly quantified. The Lesser Grey Shrike Lanius minor is a threatened farmland bird and already extinct in many areas. We monitored a population of this long-distance migrant in a traditional farming area in the Poľana Mountains (central Slovakia) in three breeding seasons (1996, 2016, and 2021). We analysed the impact of the increase in number of modern habitations and the decrease in traditional farmsteads on the population decline. The number of breeding territories decreased from 73 in 1996 to 38 in 2016 and 22 in 2021. As the population has declined, the breeding area has also shrunk significantly. While there were no modern homesteads in the breeding territories in 1996, by 2021 their number had increased to the number of traditional farmsteads. Building a single modern house in a territory reduced the probability of nesting to about 6%, and this effect was also seen when one or two farms were still present (17% and 40%, respectively). An additional modern homestead in the territory reduced the nesting probability to almost zero, even if a farmstead was already present. In this long-term empirical study, we identified these changes as a local threat factor for the species studied. The results presented can help in the design and implementation of conservation measures in traditional farming landscapes.
... One of the biological consequences of these increasing levels of human development is the large-scale decline of numerous birds' population, particularly insectivorous and specialist species (Bowler et al. 2019;Clavel et al. 2011) contributing to a homogenization of bird communities (Devictor et al. 2007;Le Viol et al. 2012). Agricultural intensification has affected farmland bird populations negatively (Donald et al. 2001;Stoate et al. 2001), declining them during the past half century in Europe (European Bird Census Council 2017) and in north America (Stanton et al. 2018). During the twentieth century, wetland habitats experienced also a dramatic reduction and an increased fragmentation, because of the pressure of human activities, such as urbanization and the drainage for agricultural use (Von Behren 2007;Whited et al 2000;Czech and Parsons 2002). ...
Wetland habitats experienced a dramatic reduction and fragmentation of biodiversity, because of human activities such as urbanization and agriculture. Now birds, as indicator of this biodiversity, have to breed, winter or stopover in wetlands embedded in a complex and highly altered human matrix. They may concentrate their activities in the wet remnant (wet reedbed) or suboptimal habitats (dry reedbed) and surroundings such as agricultural fields (maize). In a wide wetland area situated south-west of France in a main migration route, we tested if the abundance of passerine species differs among habitats according to their specialization and ecology (wet reedbed vs dry habitats; aquatics vs generalists; migrant vs local), We attempt to identify the underlying mechanisms of observed variation, looking at: arthropod availability in each habitat, bird diet of five insectivorous species and refuelling capacity of birds. Maize crops hosted more invertebrates and biomass than reedbeds for Coleoptera, Diptera, Araneida and Cicadellidae. This may explain why crops were used by aquatic passerines (Bluethroat, Sedge warblers, Reed warblers), migrant or local generalists (Robin, Blue tit, Great tit, Willow Warblers and Nightingale). Bluethroat’s diet was more focused on Formicidae and used the both habitats. In spite of the available food in maize, specialist birds preferred reedbed: Cetti warbler feeding in mainly Araneida and Cicadellidae; Sedge warbler Aphid and Coleoptera. Dry reedbed were better used by Grasshopper Warblers foraging Formicidae. Sedge and Reed warblers were more abundant in wet reedbed. We also noted for this last species youngs refuelling in maize crop. Therefore, the strategy to use maize crop may be different if resident or migrant. Generalist resident may disperse searching for food or transit area in continuity of vegetation; migrant need refuelling, particularly the aquatic trans-saharans more specialist on reedbed than the others. Finally, maize crop provided food resources and suitable shelter for a large group of species. It may be a supplement habitat of the wet and dry reedbeds, but not a substitute. Our study reaffirms to conserve and extend wet reedbed habitats threatened by clogging bush encroachment and drying.
Breeding mallard ( Anas platyrhynchos ) populations in the Great Lakes region (Michigan, Minnesota, Wisconsin, USA) declined by >40% between 2000–2022 based on abundance data collected during spring aerial surveys. Mallards are an important waterfowl species in this region, where an estimated 60–80% of the mallard harvest is composed of locally banded birds. Extensive population monitoring datasets are available for mallards, presenting an opportunity to address complex questions such as estimating productivity at large spatial and temporal scales, identifying the effects of harvest on mallard demography, quantifying mechanisms for harvest compensation, and integrating multiple datasets to quantify the demographic drivers of population change. Our objective was to simultaneously examine factors affecting demographic parameters and their relative contribution to Great Lakes mallard population dynamics. We used 32 years of banding, band recovery, and aerial survey data collected for mallards from Michigan and Wisconsin to develop an integrated population model (IPM). We used age ratios at banding to estimate productivity, band recoveries from hunter‐harvested birds to estimate annual survival and cause‐specific mortality (i.e., harvest or non‐hunting), and modeled abundance using aerial survey and demographic parameter estimates from 1991–2022. The IPM results indicated the decline in Great Lakes mallard abundance was caused by increased non‐hunting mortality and a decline in productivity. Productivity varied spatially but temporally declined with the loss of Conservation Reserve Program area. Moreover, our productivity assessment provided evidence of density dependence in reproduction. Non‐hunting mortality was 3.5–6.7 times and 1.3–4.2 times greater than harvest mortality for adult and juvenile female mallards, respectively, indicating environmental factors during spring and summer, not harvest, most greatly influenced annual mortality for female mallards. Our IPM reduced uncertainty in the factors affecting Great Lakes mallard population dynamics and indicated management actions that address non‐hunting mortality and productivity would be most effective in increasing Great Lakes mallard abundance.
Diante a preocupação com a contaminação do ambiente devido ao uso intensivo de pesticidas na agricultura brasileira, a exemplo no estado de Mato Grosso, se faz necessário analisar as particularidades que os ingredientes ativos (i.a.) exercem no ambiente para auxiliar na diminuição dos seus impactos, sendo o Índice de Risco Ambiental (IRA) um meio de conhecer esses danos. Assim, o objetivo desse estudo foi realizar o IRA dos herbicidas mais utilizados no Mato Grosso para controle de plantas daninhas nas culturas da soja, milho e algodão. O levantamento foi realizado por i.a., a partir de dados do Instituto de Defesa Agropecuária de Mato Grosso, enquanto que as características físico-químicas dos herbicidas, necessárias para as equações do IRA, foram obtidas de três bancos de dados (PPDB, PPD e IBAMA). Os parâmetros utilizados para a construção do IRA foram: persistência no solo, lixiviação, volatilidade, dose e perfil toxicológico dos herbicidas. A pesquisa apontou 42 herbicidas usados, porém 11 compostos representam 98,2% do volume total comercializado, sendo o glyphosate o primeiro do ranking com massa total de 134.138.025 kg i.a. comercializado nos últimos três anos em Mato Grosso. O resultado do IRA da maior massa comercializada em ordem decrescente foi: atrazine, diuron, trifluralin, glyphosate, 2,4-D, clomazone, S-metolachlor, diquat, haloxifop-methyl, clethodim e glufosinate-amonnium. Os herbicidas atrazine, MSMA, diuron, trifluralin e pendimethalin, foram os i.a. que apresentaram maior IRA. De modo geral, todos os herbicidas apresentaram níveis de toxicidade de médio a muito alto, resultando em um fator preocupante aos ecossistemas, quando atingem organismos não-alvos.
Plant protection products (PPPs) have historically been one of the classes of chemical compounds at the frontline of raising scientific and public awareness of the global nature of environmental pollution and the role of trophic interactions in shaping the impacts of chemicals on ecosystems. Despite increasingly strong regulatory measures since the 1970s designed to avoid unintentional effects of PPPs, their use is now recognised as a driver of biodiversity erosion. The French Ministries for the Environment, Agriculture and Research commissioned a collective scientific assessment to synthesise the current science and knowledge on the impacts of PPPs on biodiversity and ecosystem services. Here we report a literature review of the state of knowledge on the propagation of PPP residues and the effects of PPPs in food webs, including biopesticides, with a focus on current-use PPPs. Currently used PPPs may be stronger drivers of the current biodiversity loss than the banned compounds no longer in use, and there have been far fewer reviews on current-use PPPs than legacy PPPs. We first provide a detailed overview of the transfer and propagation of effects of PPPs through trophic interactions in both terrestrial and aquatic ecosystems. We then review cross-ecosystem trophic paths of PPP propagation, and provide insight on the role of trophic interactions in the impacts of PPPs on ecological functions. We conclude with a summary of the available knowledge and the perspectives for tackling the main gaps, and address areas that warrant further research and pathways to advancing environmental risk assessment.
Graphical abstract
Відновлювані джерела енергії, зокрема, й сонячні електростанції, в останні десятиліття набувають все більшого поширення. У зв’язку із значним зниженням собівартості сонячних панелей за останні два десятиліття, можна очікувати збльшення кількості фотоелектричних установок. Це призведе до формування і поширення нового виду антропогенно-трансформованих ландшафтів. За останнє десятиліття були опубліковані роботи, присвячені оцінці впливу сонячних електростанцій на ґрунтовий покрив, рослинність, тваринний світ, зокрема, орнітофауну. Основний акцент у цих дослідженях робиться на факторі загибелі із прогнозуванням пташиної смертності у міру збільшення сумарної потужності та площі фотоелектричних установок. Дослідники доходять висновку про недостатність наявних даних для розуміння повної картини всіх складних взаємовз’язків між абіотичним та біотичним складовими цього нового середовища існування. Станом на сьогодні вже достеменно відомо, що смертність птахів на об’єктах сонячної енергетики є найнижчою у порівнянні як із об’єктами, що працюють на викопному паливі, так і на інших джерелах відновлюваної енергії. Деякі результати свідчать навіть про позитивний вплив фотоелектричних установок на біорізноманіття, у порівнянні із іншими техногенно-трансформованими ландшафтами. Дослідження задокументували різні механізми, за допомогою яких сонячні електростанції можуть впливати на популяції птахів. Фізична присутність сонячних панелей може порушити маршрути польоту та місця гніздування. Однак також зазначається, що відбиваючі поверхні фотоелектричних панелей можуть приваблювати комах, що, у свою чергу, надає нові можливості для годування деяких видів птахів. Узагальнити наявну на даний час інформацію про світовий досвід оцінки впливу сонячних електростанцій на птахів й покликана дана робота.
Migratory shorebirds are one of the fastest declining groups of North American avifauna. Yet, relatively little is known about how these species select habitat during migration. We explored the habitat selection of Buff-breasted Sandpipers (Calidris subruficollis) during spring and fall migration through the Texas Coastal Plain, a major stopover region for this species. Using tracking data from 118 birds compiled over 4 years, we found Buff-breasted Sandpipers selected intensively managed crops such as sod and short-stature crop fields, but generally avoided rangeland and areas near trees and shrubs. This work supports prior studies that also indicate the importance of short-stature vegetation for this species. Use of sod and corn varied by season, with birds preferring sod in spring, and avoiding corn when it is tall, but selecting for corn in fall after harvest. This dependence on cropland in the Texas Coastal Plain is contrary to habitat use observed in other parts of their non-breeding range, where rangelands are used extensively. The species' almost complete reliance on a highly specialized crop, sod, at this critical stopover site raises concerns about potential exposure to contaminants as well as questions about whether current management practices are providing suitable conditions for migratory grassland birds.
Grasslands are one of the most threatened terrestrial biomes leading to a loss of grassland biodiversity, including birds. Here, we studied the wintering grassland bird diversity and community structure in two private livestock ranches in the Chihuahuan Desert, Mexico. We explored how bird communities are related to vegetation structure, including shrub cover and invasive exotic natal grass (Melinis repens), two drivers of grassland bird habitat degradation. We used Hill’s numbers to estimate taxonomic species richness and diversity and related these metrics to vegetation covariables using linear models. We employed nonmetric dimensional scaling (NMDS) to explore the importance of vegetation covariates in structuring bird communities. We found that bird species diversity was significantly and negatively related to bare ground cover at a plot level. At the ranch level, shrub cover, grass height and natal grass were important in structuring avian communities, negatively affecting the presence and abundance of grassland specialist bird species. Our results indicated that shrub encroachment and invasive exotic natal grass cover may alter grassland bird communities and should, therefore, be considered in grassland bird conservation management.
Context
Promoting heterogeneous agricultural landscapes could help to reduce the negative impacts of habitat conversion on biota. However, the benefits of landscape heterogeneity can vary among spatial scales and taxa.
Objectives
To design biodiversity-friendly landscapes, we use nationwide bird survey data and land use maps to examine the effects of compositional heterogeneity, configurational heterogeneity, and habitat amount at different scales on the species richness of different bird groups.
Methods
We examine the effects of configurational heterogeneity (measured using edge density), compositional heterogeneity (Shannon’s diversity index of habitat types), and habitat amount (proportion of forest and farmland cover) at both transect (local) and landscape (0.5, 1, or 2 km) scales on the species richness of all breeding birds, forest birds, farmland birds, and introduced birds.
Results
Total species richness had a hump-shaped relationship with local forest cover, and with farmland cover at landscape scale. Richness of both forest birds and richness of farmland birds increased with Shannon’s diversity index of habitat types at both local and landscape scales, but only increased with the amount of their preferred habitat at the local scale. Richness of introduced birds was greater in landscapes with higher edge density, suggesting those species are associated with human-dominated landscapes.
Conclusions
High compositional heterogeneity with low configurational heterogeneity at the landscape scale may help maintain native bird richness while minimising the spread of introduced species in Taiwan. These results can help guide land use planning to achieving biodiversity goals in a country with intensive land-use competition.
Birds that travel long distances between their wintering and breeding grounds may be particularly susceptible to neurotoxic insecticides, but the influence of insecticides on migration ability is poorly understood. Following acute exposure to two widely used agricultural insecticides, imidacloprid (neonicotinoid) and chlorpyrifos (organophosphate), we compared effects on body mass, migratory activity and orientation in a seed-eating bird, the white-crowned sparrow (Zonotrichia leucophrys). During spring migration, sparrows were captured, held and dosed by gavage daily for 3 days with either the vehicle control, low (10% LD50) or high (25% LD50) doses of imidacloprid or chlorpyrifos and tested in migratory orientation trials pre-exposure, post-exposure and during recovery. Control birds maintained body mass and a seasonally appropriate northward orientation throughout the experiment. Imidacloprid dosed birds exhibited significant declines in fat stores and body mass (mean loss: −17% low, −25% high dose) and failed to orient correctly. Chlorpyrifos had no overt effects on mass but significantly impaired orientation. These results suggest that wild songbirds consuming the equivalent of just four imidacloprid-treated canola seeds or eight chlorpyrifos granules per day over 3 days could suffer impaired condition, migration delays and improper migratory direction, which could lead to increased risk of mortality or lost breeding opportunity.
Significance
Prairie strips are a new conservation technology designed to alleviate biodiversity loss and environmental damage associated with row-crop agriculture. Results from a multiyear, catchment-scale experiment comparing corn and soybean fields with and without prairie vegetation indicated prairie strips raised pollinator and bird abundance, decreased water runoff, and increased soil and nutrient retention. These benefits accrued at levels disproportionately greater than the land area occupied by prairie strips. Social surveys revealed demand among both farm and nonfarm populations for the outcomes prairie strips produced. We estimated prairie strips could be used to improve biodiversity and ecosystem services across 3.9 million ha of cropland in Iowa and a large portion of the 69 million ha under similar management in the United States.
Throughout North America, many species of aerial insectivorous birds have exhibited steep declines. The timing of these declines coincides with changes in agriculture, perhaps signaling a causal link. Increased agrochemical use, wetland drainage, and cropping intensity may indirectly influence insectivores by reducing the abundance of insect prey. Our objective was to determine whether changes in insect abundance and biomass on agricultural landscapes in the Canadian Prairies influence the foraging behaviour of breeding Tree Swallows (Tachycineta bicolor (Vieillot, 1808)). Swallows were studied at five sites with varying levels of agricultural intensity in Saskatchewan, where insect abundance and biomass were monitored daily with passive aerial samplers. Radio-frequency identification (RFID) technology was employed at Tree Swallow nest boxes to investigate adult foraging behaviour. Foraging rates (number of nest visits/h) were slightly higher on agricultural sites than at grassland sites, and were positively related to daily insect biomass and nestling age. Tree Swallows, especially males, breeding at agricultural sites spent more time away from the nest box, presumably foraging, resulting in reduced nest attentiveness. RFID technology provides an effective technique to measure behaviour in birds and these findings suggest mechanisms by which prey abundance and agricultural land use may affect declining aerial insectivorous bird populations.
Birds populations allied in abundance
Changes in climate can cause populations of species to decline, to increase, or to remain steady. Stephens et al. looked across species of common birds in Europe and the United States. Despite many differences between the two regions, expectations about how a species might respond to climate change did predict actual responses. Species predicted to benefit from increasing temperatures, or their associated effects, tended to increase, whereas those predicted to be negatively affected declined. Thus, even across widely varying ecological conditions and communities, climate change can be expected to alter population sizes.
Science , this issue p. 84
In the northeastern United States, grassland birds regularly use agricultural fields as nesting habitat. However, birds that nest in these fields regularly experience nest failure as a result of agricultural practices, such as mowing and grazing. Therefore, information on both spatial and temporal patterns of habitat use is needed to effectively manage these species. We addressed these complex habitat use patterns by conducting point counts during three time intervals between May 21, 2002 and July 2, 2002 in agricultural fields across the Champlain Valley in Vermont and New York. Early in the breeding season, Bobolinks (Dolichonyx oryzivorus) used fields in which the landscape within 2500 m was dominated by open habitats. As mowing began, suitable habitat within 500 m became more important. Savannah Sparrows (Passerculus sandwichensis) initially used fields that contained a high proportion of suitable habitat within 500 m. After mowing, features of the field (i.e., size and amount of woody edge) became more important. Each species responded differently to mowing: Savannah Sparrows were equally abundant in mowed and uncut fields, whereas Bobolinks were more abundant in uncut fields. In agricultural areas in the Northeast, large areas (2000 ha) that are mostly nonforested and undeveloped should be targeted for conservation. Within large open areas, smaller patches (80 ha) should be maintained as high-quality, late-cut grassland habitat.
Many animal species exhibit spatiotemporal synchrony in population fluctuations, which may provide crucial information about ecological processes driving population change. We examined spatial synchrony and concordance among population trajectories of five aerial insectivorous bird species: Chimney Swift (Chaetura pelagica), Purple Martin (Progne subis), Barn Swallow (Hirundo rustica), Tree Swallow (Tachycineta bicolor), and Northern Rough-winged Swallow (Stelgidopteryx serripennis). Aerial insectivores have undergone severe guild-wide declines that were considered more prevalent in northeastern North America. Here, we addressed four general questions including spatial synchrony within species, spatial concordance among species, frequency of declining trends among species, and geographic location of declining trends. We used dynamic factor analysis to identify large-scale common trends underlying stratum-specific annual indices for each species, representing population trajectories shared by spatially synchronous populations, from 46 years of North American Breeding Bird Survey data. Indices were derived from Bayesian hierarchical models with continuous autoregressive spatial structures. Stratum-level spatial concordance among species was assessed using cross-correlation analysis. Probability of long-term declining trends was compared among species using Bayesian generalized linear models. Chimney Swifts exhibited declining trends throughout North America, with less severe declines through the industrialized Mid-Atlantic and Great Lakes regions. Northern Rough-winged Swallows exhibited declining trends throughout the west. Spatial concordance among species was limited, the proportion of declining trends varied among species, and contrary to previous reports, declining trends were not more prevalent in the northeast. Purple Martins, Barn Swallows, and Tree Swallows exhibited synchrony across smaller spatial scales. The extensive within-species synchrony and limited concordance suggest that population trajectories of these aerial insectivores are responding to large-scale but complex and species- and region-specific environmental conditions (e.g., climate, land use). A single driver of trends for aerial insectivores as a guild appears unlikely.This article is protected by copyright. All rights reserved.
We reviewed cases of raptor mortality resulting from cholinesterase-inhibiting pesticides. We compiled records from the U.S., U.K. and Canada for the period 1985-95 (520 incidents) and surveyed the relevant literature to identify the main routes of exposure and those products that led to the greatest number of poisoning cases. A high proportion of cases in the U.K. resulted from abusive uses of pes- ticides (willful poisoning). The proportion was smaller in North America where problems with labeled uses of pesticides were as frequent as abuse cases. Poisoning resulting from labeled use was possible with a large number of granular pesticides and some seed treatments through secondary poisoning or through the ingestion of contaminated invertebrates, notably earthworms. With the more toxic products, residue levels in freshly-sprayed insects were high enough to cause mortality. The use of organophos- phorus products as avicides and for the topical treatment of livestock appeared to be common routes of intoxication. The use of insecticides in dormant oils also gave rise to exposure that can be lethal or
A B S T R A C T Many studies have established that birds may provide a pest removal service on farms, although few studies have taken place in temperate row crop agriculture. Wildlife-friendly agricultural practices such as organic farming and the use of hedgerows can in turn provide needed habitat for birds in developed landscapes. In this study, we examined how pest removal provided by birds varies within and between " wildlife-friendly " organic row-crop farms in northern California, USA. We used point counts to assess bird diversity on 29 small organic farms and simulated lepidopteran pest outbreaks on each farm using sentinel pest experiments. We measured how the probability of pest removal varied with local habitat characteristics within the farm, and with bird diversity parameters between farms. We also used exclosure experiments to determine whether birds provide a significant pest removal service in organic row-crop agriculture. In the sentinel pest experiments, birds depredated between 0 and 80% of caterpillar presentation stations within 7 h, with a mean of 24% depredation per farm; the probability of pest removal was higher in areas close to uncultivated shrubby field margins (" hedgerows "). There was only weak evidence that the probability of pest removal was higher on farms with higher avian insectivore richness, and no evidence that pest removal varied with species diversity or abundance. Exclosure experiments on kale crops showed no significant effects of bird exclosure treatment on arthropod abundance or crop yield. However, natural caterpillar densities were relatively low during the exclosure experiment (approximately one caterpillar/m 2). These results suggest that birds may be more helpful in responding to pest outbreaks than in controlling pests at non-irruptive densities on organic row crop farms in this study system. The prevention of pest outbreaks is an essential ecosystem service on any farm, and the rapid response of birds to pest outbreak conditions is an indicator of resiliency in the agroecosystem. Therefore, the retention of uncultivated shrubby field margins in this system may benefit both birds and farmers.
Grasslands cover more than 40% of Earth's land surface and are the most converted, yet least protected, biome worldwide (Hoekstra et al. 2005). As a guild, grassland birds have declined more rapidly than birds of any other habitat type in North America (Herkert 1995). These statistics might be expected to generate a lot of attention to conservation in this biome; however, just as ignorance about one of the most strident prairie birds gave rise to its scientific name, Sturnella neglecta (Audubon 1840), knowledge regarding the ecology and conservation of grasslands and grassland birds lags behind that of other ecosystems. For example, a search of ISI Web of Knowledge® research turned up less than one third the number of papers about grassland (1445) as forest (5200) birds. Given that 30% of Earth's surface is forested, but 40% is, or was, grassland, per unit area, almost five times more research has been reported about forest birds compared with grassland birds. Perhaps it is little wonder, then, that attributes of species' natural histories, such as territory size of Vesper Sparrows (Pooecetes gramineus; Jones and Cornelys 2002), remain unknown or uncertain.
Agricultural intensification has been linked to declines in farmland and grassland bird populations in Europe and in North America. One factor thought to be behind these declines is reduced invertebrate food abundance in the breeding season, leading to reduced reproductive success. However, little is known about foraging habitat or diet of farmland birds in North America. We used stable isotopes to study foraging habitat and diet of Song Sparrows (Melospiza melodia (A. Wilson, 1810)), a common hedgerow-breeding bird, by collecting claw clippings of Song Sparrow nestlings from farms in eastern Ontario, Canada. Mean values of δ¹³C and δ¹⁵N were compared between claws and invertebrate food sources from adjacent land-cover types, using a Bayesian mixing model. The portion of nestling diet that came from seminatural and forage habitats was higher than expected, based on the proportion of seminatural and forage cover at the nest. This was particularly evident at nests with low seminatural cover, where hedgerows were the only noncrop habitat. The most important food sources for Song Sparrow nestlings were hoppers (Auchenorrhyncha) and caterpillars (Lepidoptera). Management actions to increase invertebrate abundance in hedgerows may benefit Song Sparrows and other farmland birds with minimal impact on crop yield.
Agriculture today places great strains on biodiversity, soils, water and the atmosphere, and these strains will be exacerbated if current trends in population growth, meat and energy consumption, and food waste continue. Thus, farming systems that are both highly productive and minimize environmental harms are critically needed. How organic agriculture may contribute to world food production has been subject to vigorous debate over the past decade. Here, we revisit this topic comparing organic and conventional yields with a new meta-dataset three times larger than previously used (115 studies containing more than 1000 observations) and a new hierarchical analytical framework that can better account for the heterogeneity and structure in the data. We find organic yields are only 19.2% (±3.7%) lower than conventional yields, a smaller yield gap than previous estimates. More importantly, we find entirely different effects of crop types and management practices on the yield gap compared with previous studies. For example, we found no significant differences in yields for leguminous versus non-leguminous crops, perennials versus annuals or developed versus developing countries. Instead, we found the novel result that two agricultural diversification practices, multi-cropping and crop rotations, substantially reduce the yield gap (to 9 ± 4% and 8 ± 5%, respectively) when the methods were applied in only organic systems. These promising results, based on robust analysis of a larger meta-dataset, suggest that appropriate investment in agroecological research to improve organic management systems could greatly reduce or eliminate the yield gap for some crops or regions.
The Rusty Blackbird (Euphagus carolinus), a formerly common breeding species of boreal wetlands, has exhibited the most marked decline of any North American landbird. North American Breeding Bird Survey (BBS) trends in abundance are estimated to be ‒12.5%/yr. over the last 40 years, which is tantamount to a >95% cumulative decline. Trends in abundance calculated from Christmas Bird Counts (CBC) for a similar period indicate a range-wide decline of ‒5.6%/yr. Qualitative analyses of ornithological accounts suggest the species has been declining for over a century. Several studies document range retraction in the southern boreal forest, whereas limited data suggest that abundance may be more stable in more northerly areas. The major hypotheses for the decline include degradation of boreal habitats from logging and agricultural development, mercury contamination, and wetland desiccation resulting from global warming. Other likely reasons for decline include loss or degradation of wooded wetlands of the southeastern U.S and mortality associated with abatement efforts targeting nuisance blackbirds. In addition, the patchy breeding distribution of this species may inhibit population consolidation, causing local populations to crash when reduced to low levels. Progress in understanding the causes and mechanisms for observed declines has remained limited until recently. Here we present initial attempts to understand the habitat requirements of Rusty Blackbirds and offer specific predictions associated with each of the hypotheses for decline as a way of guiding future research.
It is now well known that biodiversity in agricultural landscapes can be increased by converting production lands (i.e., farmland) into more natural habitat. However, it remains relatively unknown to what extent biodiversity can also be enhanced by changing the composition and configuration of farmland per se. We examined relationships between farmland structure and avian biodiversity in six watersheds representing a gradient in rowcrop intensity in the American Mid-west. We used canonical correspondence analysis
(CCA) to model relationships at the site (0.8 ha), field (21 ha), section (165 ha) and watershed (4000–18,000 ha) extents to explore these questions: (1) At what spatial extent do birds respond most strongly to farmland structure? (2) Which farmland variables are most important? (3) Does avian biodiversity increase with increasing farmland heterogeneity? Most variation in bird assemblages was explained at the field versus the site or section extents. Of the top 20 field-extent variables in CCA, most important were: % woodland, an index of compositional heterogeneity (the modified Simpson’s evenness index, MSIEI), % rowcrop, % core pasture (i.e., away from an edge), and edge density. Eighteen species were associated with woodland; their richness increased with woodland from 0% to 10%. Nine species were associated with rowcrop; their richness decreased two-fold with a change in rowcrop from 80% to 3%. Twelve species were associated with farmland heterogeneity; their richness increased four-fold with more field cover heterogeneity (MSIEI) and decreased three-fold with increasing mean field size from 1.2 to 7 ha. Field-extent a and b species richness were
significantly higher than expected in the null model in the two most heterogeneous watersheds and lower in the two most intensely farmed watersheds. Differences among watersheds were significant and evident in the CCA ordination plot. Our results show empirically that policies to influence farmland heterogeneity could provide a conservation benefit to avian biodiversity.
Many common bird species have declined as a result of agricultural intensification and this could be mitigated by organic farming. We paired sites for habitat and geographical location on organic and nonorganic farms in Ontario, Canada to test a priori predictions of effects on birds overall, 9 guilds and 22 species in relation to candidate models for farming practices (13 variables), local habitat features (12 variables), or habitat features that influence susceptibility to predation. We found that: (1) Overall bird abundance, but not richness, was significantly (p < 0.05) higher on organic sites (mean 43.1 individuals per site) than nonorganic sites (35.8 individuals per site). Significantly more species of birds were observed for five guilds, including primary grassland birds, on organic vs. nonorganic sites. No guild had higher richness or abundance on nonorganic farms; (2) Farming practice models were the best (∆AIC < 4) for abundance of birds overall, primary grassland bird richness, sallier aerial insectivore richness and abundance, and abundance of ground nesters; (3) Habitat models were the best for overall richness, Neotropical migrant abundance, richness and abundance of Ontario-USA-Mexico (short-distance) migrants and resident richness; (4) Predation models were the best for richness of secondary grassland birds and ground feeders; (5) A combination of variables from the model types were best for richness or abundance overall, 13 of 18 guilds (richness and abundance) and 16 of 22 species analyzed. Five of 10 farming practice variables (including herbicide use, organic farm type) and 9 of 13 habitat variables (including hedgerow length, proportion of hay) were significant in best models. Risk modeling indicated that herbicide use could decrease primary grassland birds by one species (35% decline from 3.4 to 2.3 species) per site. Organic farming could benefit species of conservation concern by 49% (an increase from 7.6 to 11.4 grassland birds). An addition of 63 m of hedgerow could increase abundance and richness of short distance migrants by 50% (3.0 to 4.8 and 1.3 to 2.0, respectively). Increasing the proportion of hay on nonorganic farms to 50% could increase abundance of primary grassland bird by 40% (6.7 to 9.4). Our results provide support for alternative farmland designs and agricultural management systems that could enhance select bird species in farmland.
Grassland bird species have experienced substantial declines in North America. These declines have been largely attributed to habitat loss and degradation, especially from agricultural practices and intensification (the habitat-availability hypothesis). A recent analysis of North American Breeding Bird Survey (BBS) "grassland breeding" bird trends reported the surprising conclusion that insecticide acute toxicity was a better correlate of grassland bird declines in North America from 1980-2003 (the insecticide-acute-toxicity hypothesis) than was habitat loss through agricultural intensification. In this paper we reached the opposite conclusion. We used an alternative statistical approach with additional habitat covariates to analyze the same grassland bird trends over the same time frame. Grassland bird trends were positively associated with increases in area of Conservation Reserve Program (CRP) lands and cropland used as pasture, whereas the effect of insecticide acute toxicity on bird trends was uncertain. Our models suggested that acute insecticide risk potentially has a detrimental effect on grassland bird trends, but models representing the habitat-availability hypothesis were 1.3-21.0 times better supported than models representing the insecticide-acute-toxicity hypothesis. Based on point estimates of effect sizes, CRP area and agricultural intensification had approximately 3.6 and 1.6 times more effect on grassland bird trends than lethal insecticide risk, respectively. Our findings suggest that preserving remaining grasslands is crucial to conserving grassland bird populations. The amount of grassland that has been lost in North America since 1980 is well documented, continuing, and staggering whereas insecticide use greatly declined prior to the 1990s. Grassland birds will likely benefit from the de-intensification of agricultural practices and the interspersion of pastures, Conservation Reserve Program lands, rangelands and other grassland habitats into existing agricultural landscapes.
Research on and interest in grassland birds have increased considerably in the past 20 yr. There are several reasons for this heightened interest. Foremost, it is clear that populations of many grassland birds have declined sharply throughout the Western Hemisphere (e.g., Bucher and Nores 1988, Cavalcanti 1988, Fjeldsa 1988, McNicholl 1988, Knopf 1994, Peterjohn and Sauer 1999). In North America, populations of at least 13 species of grassland birds declined significantly between 1966 and 1995 (Peterjohn and Sauer 1999). And as a group, North American grassland birds have experienced “steeper, more consistent, and more geographically widespread declines than any other behavioral or ecological guild,” largely because of habitat loss and degradation (Knopf 1994:251). Similar declines are also occurring in South America, where species such as Pampas Meadowlark (Sturnella defilippii; Tubaro and Gabelli 1999), Saffron-cowled Blackbird (Agelaius flavus; Fraga et al. 1998), and Sporophila seedeaters (Silva 1999) have declined in the past 20 yr. Indeed, Collar et al. (1992:35) describe the “near-total destruction of open grasslands in south-east Brazil…and in the vast central planalto…as one of the great ecological catastrophes in South America.”
Another reason for the increased research interest in grassland birds is changing agricultural practices. For example, the U.S. Department of Agriculture’s Conservation Reserve Program (CRP), which has taken more than 14 million ha of cropland out of production under 10-yr contracts, has made it possible to examine regional, and even continental, effects of changing landscapes on grassland birds (e.g., Lauber 1991, Reynolds et al. 1994, Herkert 1998). Additionally, the CRP has provided excellent opportunities to study bird colonization, habitat use, and nesting success in different regions and under different ecological conditions. Finally, grassland birds are also fascinating from ecological and evolutionary perspectives. Distinctive or unusual adaptations, such as large body size and cursorial habits, have evolved in grassland birds. And the ability to readily observe many behaviors makes these species ideal for research (e.g., Wheelwright and Mauck 1998).
In recent years, neonicotinoid insecticides have been the fastest growing class of insecticides in modern crop protection, with widespread use against a broad spectrum of sucking and certain chewing pests. As potent agonists, they act selectively on insect nicotinic acetylcholine receptors (nAChRs), their molecular target site. The discovery of neonicotinoids can be considered as a milestone in insecticide research and greatly facilitates the understanding of functional properties of the insect nAChRs. In this context, the crystal structure of the acetylcholine-binding proteins provides the theoretical foundation for designing homology models of the corresponding receptor ligand binding domains within the nAChRs, a useful basis for virtual screening of chemical libraries and rational design of novel insecticides acting on these practically relevant channels. Because of the relatively low risk for nontarget organisms and the environment, the high target specificity of neonicotinoid insecticides, and their versatility in application methods, this important class has to be maintained globally for integrated pest management strategies and insect resistance management programs. Innovative concepts for life-cycle management, jointly with the introduction of generic products, have made neonicotinoids the most important chemical class for the insecticide market.
Agriculture is a primary factor underlying world-wide declines in biodiversity. However, different agricultural systems vary in their effects depending on their resemblance to the natural ecosystem, coverage across the landscape, and operational intensity. We combined data from the North American Breeding Bird Survey with remotely sensed measures of crop type and linear woody feature (LWF) density to study how agricultural type, woody structure and crop heterogeneity influenced the avian community at landscape scales across a broad agricultural region of eastern Canada. Specifically, we examined whether 1) avian diversity and abundance differed between arable crop agriculture (e.g., corn, soy) and forage (e.g., hay) and pastoral agriculture, 2) whether increasing the density of LWF enhances avian diversity and abundance, and 3) whether increasing the heterogeneity of arable crop types can reduce negative effects of arable crop amount. Avian diversity was lower in landscapes dominated by arable crop compared to forage agriculture likely due to a stronger negative correlation between arable cropping and the amount of natural land cover. In contrast, total avian abundance did not decline with either agricultural type, suggesting that species tolerant to agriculture are compensating numerically for the loss of non-tolerant species. This indicates that bird diversity may be a more sensitive response than bird abundance to crop cover type in agricultural landscapes. Higher LWF densities had positive effects on the diversity of forest and shrub bird communities as predicted. Higher crop heterogeneity did not reduce the negative effects of high crop amount as expected except for wetland bird abundance. In contrast, greater crop heterogeneity actually strengthened the negative effects of high crop amount on forest bird abundance, shrub-forest edge bird diversity and total bird diversity. We speculate that this was due to negative correlations between crop heterogeneity and the amount of shrub and forest habitat patches in crop-dominated landscapes in our study region. The variable response to crop heterogeneity across guilds suggests that policies aimed at crop diversification may not enhance avian diversity on their own and that management efforts aimed at the retention of natural forest and shrub patches, riparian corridors, and hedge-rows would be more directly beneficial.
Summaries ot toxicological data for wildlife are given for each pesticide in alphabetical order, with information provided on; alternative names for each chemical, chemical name; primary use; sample purity; acute oral toxicity for selected wildlife species; and signs of intoxication.-P.J.Jarvis
Organic farming may be more beneficial to biodiversity than nonorganic farming but the comparison is often confounded by regional within-farm and landscape differences. We compared breeding bird species composition and abundance on 10 farm pairs of each type matched at the site level for land cover in the prairie parklands of Saskatchewan, Canada in 1990. Land cover was measured around bird point counts at two extents; ‘site’ (6.3 ha area) and ‘field’ (16.3 ha area). We pooled species into functional groups; linear mixed models showed no significant differences between farm types for species richness but that all birds, migratory birds using crops and aerial insectivores were more abundant on organic farms. A permutational multivariate analysis of variance demonstrated that farm type did not have a significant overall effect on compositional similarity but that pairwise differences existed between about half of the farm pairs (the direction of differences in beta diversity was not consistent between organic and nonorganic farms according to tests for the homogeneity of multivariate dispersions). Farm-pair differences were more pronounced for all birds and for migratory bird species using crops, migratory birds consuming grains and ground feeders, but not grassland birds. nMDS ordinations suggested that there was more variation in species composition and abundance on organic farms than nonorganic ones but the difference was not significant. Distance-based redundancy analysis (dbRDA) was used to examine the main drivers of bird species composition and abundance and to see which extent was most important; land cover at the field extent was more important than land cover at the site extent or the farming practices measured. The most important field-extent land cover was the amount of native grassland, woodland (including shelterbelts) and wetlands. After controlling for significant field-extent land cover, seed treatment, herbicide use, and number of passes were significant. At the site extent, greater non-crop heterogeneity had a significantly positive effect on abundance and species richness of several groups (e.g., grassland birds, migratory granivores, ground feeders, ground nesters) but a negative effect on richness of woodland birds and abundance of aerial insectivores. Relationships with crop heterogeneity were mostly negative and non-significant. Overall land cover heterogeneity at the site level was positively related to the richness of grassland birds. In contrast at the field extent, non-crop heterogeneity did not have any significant effects on the richness and abundance of any functional group. Crop heterogeneity had a significantly negative effect on aerial insectivore richness and abundance. In the early 1990s, differences in birds between organic and nonorganic farms in Saskatchewan were evident but subtle and variable among farms, and apparently most related to land cover-bird assemblage interactions/relationships.
Conservation payments lead to improvement in environmental quality only if farmers and ranchers who receive them adopt conservation practices that would not have been adopted without the payment. When a voluntary payment causes a change in practice(s) that lead(s) to improved environmental quality, these changes are “additional.” We estimate this “additionality” for a number of common conservation practices that are frequently supported by existing conservation programs. We find that the level of additionality varies by practice and that additionality is high for structural and vegetative practices while the risk of nonadditionality appears to be higher for management practices. While the risk of nonadditionality cannot be completely eliminated, it can be reduced. We discuss a number of approaches to managing nonadditionality in both conservation programs and environmental offset programs.
Vegetation typical of the tallgrass prairie occurs east of the Great Plains in bottomland “openings” and as small “glades” or “balds” within the eastern deciduous forest. West of the Mississippi River, however, coverage by tallgrass prairie expands with the increasingly greater aridity under the deepening rainshadow of the western mountains. Along the Kansas-Missouri border on the western fringe of the deciduous forest, prairie is present across 50–80% of the region (Schroeder 1983). Forested area within this prairie-forest mosaic continues to diminish, decreasing to as little as 7% in the Flint Hills Uplands (Knight et al. 1994). The portion of the Great Plains characterized by the tallgrass prairie community exists in a climate that allows the development of forest as a bordering “gallery” along stream courses. These naturally occurring forest fragments, these island remnants of the continental forest to the east, remain an integral aspect of the tallgrass prairie landscape, contributing a disproportionately greater component, considering the small extent of their coverage, to the regional avian species richness (Faanes 1984, Zimmerman 1993).
Reserving large patches of perennial vegetation has been shown to facilitate biodiversity conservation in industrial agricultural landscapes, but high demand for agricultural products challenges their establishment. Responding to this situation, in 2007, we experimentally integrated diverse native perennial vegetation (i.e., prairie) within annual row crops as a part of the Science-based Trials of Rowcrops Integrated with Prairie Strips (STRIPS) project in Iowa, USA. Four treatments were applied to small (0.47–3.19 ha) watersheds and included: 100% row crops (0% prairie) farmed on a soybean (Glycine max)—maize (Zea mays) rotation, and three treatments with prairie strips comprising 10% or 20% of the watershed area with the remaining area in row crops. This study evaluated bird response to these treatments between 2007 and 2012. We observed a total of 52 species using the experimental sites across six years of study, with 16 species comprising 99% of the observations. Bird abundance, species richness, and diversity positively responded to prairie within row-crop fields: we specifically recorded 1.53–2.88 times more birds, 1.53–2.13 times more bird species, and 1.40-1.98 times greater diversity in treatments with prairie compared to the 0% prairie control. Several generalist species – Eastern kingbird (Tyrannus tyrannus), American robin (Turdus migratorius), and common yellowthroat (Geothlypis trichas) – were statistically more abundant in treatments with prairie, and song sparrow (Melospiza melodia) were more abundant in one specific prairie treatment, whereas no species was statistically more abundant in the 0% prairie control. We found few differences between 10% and 20% prairie treatments, but recorded increases in bird abundance, richness, and diversity from 2007 to post-establishment years. This experiment suggests that incorporating prairie strips into annual row crops has the potential to increase agricultural land sharing by birds.
The present paper deals with the energy content values of certain predatory insects in a pond of Santhal Parganas (Bihar). The calorific value of coleopteran insects was found maximum in JuIy (5.706 ± 0.557 k cal/g dry wt.) and minimum in January (5.007 ± 0.090 k cal/g dry wt.), whereas the hemipteran insects showed maximum calorific value in June (4.958 ± 0.83 k cal/g dry wt.) and minimum in November (4.348 ± 0.159 k cal/g dry wt.). The odonate larvae also exhibited variations and found maximum (5.487 ± 0.003 k cal/g dry wt.) in January. The possible factors for these variations have also been discussed.
Past projections of conservation tillage adoption are briefly reviewed. Also discussed is the definition used by the US Department of Agriculture in its 1975 projection and how the definition has changed. Previous Soil Conservation Service acreage estimates of conservation tillage, beginning in 1968, are discounted in an attempt to better reflect today's definition. The 1968 discounted figure is then used in an S-shaped adoption curve, under given assumptions, to make an upper and lower projection of conservation tillage. This projection indicates that conservation tillage may be adopted on 63% to 82% of the total planted cropland acres by the year 2010. -from Author