Ground-nesting Bird Species Research Articles

Brood protection is essential but not sufficient for population survival of lapwings Vanellus vanellus in central Switzerland

Lapwing are among those ground nesting bird species that suffered strong population declines following agricultural intensification in many parts of Europe. The key problem appears to be a low breeding success which, depending on the situation, may be due to predation of eggs and chicks, starvation of chicks especially during dry conditions, agricultural activities leading to direct killings, and suboptimal breeding habitat. Here, we report on a population of 40–60 lapwing breeding pairs in an intensively cultivated arable landscape in central Switzerland, where protection from farming activities, implementation of special lapwing habitat and nest fencing to exclude terrestrial predators (mainly red fox) started in 2005 and is still ongoing. Chicks were ringed and families subsequently observed every 2–3 days. Hatching success for fenced nests built before May was high. Low hatching success was observed in unfenced nests due to high predation rates and in late nests due to abandonment by the female when the vegetation was growing too tall (e.g. maize). Regularly, chicks disappeared during the night shortly after hatching. Most likely many of them first left the fence and were predated outside. Our observations from a fenced field with wet soils and puddles suggest that lapwing may produce sufficient offspring if predation can be reduced and if large enough areas with suitable habitat are available.

Facets of the nesting ecology of a ground-nesting bird, the Spotted Thick-knee, in an urban mosaic landscape

Ground-nesting bird species are typically threatened when their natural habitats are removed or altered through urbanisation. Despite this, some species, like the Spotted Thick-knee (Burhinus capensis), persist in urban mosaic landscapes. Our study was undertaken to collect novel information on Spotted Thick-knee persistence in an urban mosaic landscape by investigating facets of its nesting ecology in Pietermaritzburg, South Africa. We collected Spotted Thick-knee nesting and nest site data between July 2019 and December 2020. We conducted direct observations at 33 nest sites, and additional remote monitoring with camera traps at eight nest sites. Spotted Thick-knee breeding pairs showed select habitat and nest-site preferences (greater use of shrub-like species for nest-site placement, more grass cover, shorter grass, and flatter slopes at nest sites) compared with random sites. Successful nesting outcomes were significantly greater than failed nesting outcomes. Incubation activity was significantly longer during the day, and incubation activity had a significant adverse relationship with disturbance in human-modified habitats. Land use and human activity influenced nest-site selection and survival of nests. Spotted Thick-knee used residential gardens and recreational areas as nest sites in the urban mosaic, although nests were more successful in residential gardens. They used shrub-like vegetation as nest-cover structures, possibly because of added protection from extreme weather or less visual detection. Risks associated with nesting in human-modified habitats included increased threats from domestic animals and incubation activity costs because of disturbance around nest sites. There are relatively few studies on ground-nesting birds in urban areas, so further research is needed to determine how our results compare with other species.

Population trends of ground-nesting birds indicate increasing environmental impacts from Eastern to Western Europe: different patterns for open-habitat and woodland species

Introduction: Bird populations reflect the influence of major environmental changes, and the analysis of their long-term population trends concerning species-specific ecological traits can provide insight into biologically relevant impacts of such changes. In this respect, nest site is a particularly informative trait because ground-nesting bird species are more prone, in contrast to species nesting above the ground, to the impacts of nest predation which can be linked to various environmental drivers including the intensification of agriculture or woodland management. Here we hypothesize that a) ground-nesting species present negative trends due to environmental pressures mentioned above, b) such declining trends should be more pronounced in Western than in Eastern Europe because, in Western countries, the environmental threats are likely greater, and c) the interaction between nest site and habitat association will point at the habitat types where the presumed drivers most likely operate.Methods: We used population trends from 1980 to 2016 of 332 bird species in 16 European countries to test this hypothesis.Results: We found that the long-term population trends of ground-nesting birds are more negative than the trends of species nesting above the ground indicating the effect of nest predation, and this difference increased from Eastern to Western European countries, probably due to steeply increasing populations of nest predators in the West. However, the effect of longitude interacted with the habitat association being strong in woodland species and weak in open-habitat species.Discussion: This pattern suggests that the increased nest predation pressure in the West is linked to woodlands, probably due to higher abundances of mammalian herbivores that destroy forest ground and shrub layer, and thus leave the nests exposed to predators. In contrast, only a weak longitudinal pattern in open-habitat species indicates that the negative impacts of agricultural intensification are no longer confined to the Western part of the continent. Although nature conservation activities are generally successful in Europe, as indicated by benefits provided by the Natura 2000 network, our results uncovered substantial gaps in delivering such benefits.

Varying response of breeding waders to experimental manipulation of their habitat and predators

Many ground-nesting bird species including waders are of conservation concern across Europe. Population declines of Eurasian Curlew Numenius arquata (hereafter Curlew), a globally Near-threatened wader, exemplify this and are driven by low breeding success due to predation, and loss and degradation of breeding habitat. We tested whether the combined delivery of vegetation management and lethal control of Red Foxes Vulpes vulpes and Carrion Crows Corvus corone and Hooded Crows C. cornix improved Curlew nesting success and breeding abundance across UK study sites over five years. On trial sites, vegetation management improved habitat condition and Curlew distributions shifted towards managed areas. However, changes in predator abundances, Curlew nesting success and Curlew breeding abundance did not differ between trial and reference sites. Northern Lapwing Vanellus vanellus numbers increased on trial sites and decreased on reference sites, whilst Common Snipe Gallinago gallinago numbers showed no treatment response. Some of these outcomes were associated with additional environmental variables added to Treatment:Year terms in three-way interactions (changes in fox abundance associated with abundance of non-native gamebirds; changes in Crow abundance associated with gamebirds and woodland area; changes in Curlew nesting success associated with crow abundance), highlighting that outcomes depend on site-specific contexts, and consistent responses to interventions cannot be assumed. The difficulty in increasing Curlew nesting success likely relates to underlying mesopredator densities in the UK, which are known to be high in a European context. Our results suggest that a model of delivery like this study, including management of predators using lethal control, at comparable intensities, is highly unlikely to be effective for Curlew or Snipe within agri-environment schemes, but could be for Northern Lapwing. To make progress on wader recovery it is imperative to understand the underlying drivers of high mesopredator densities and address these through landscape-scale intervention and policy changes.

Accounting for predator species identity reveals variable relationships between nest predation rate and habitat in a temperate forest songbird.

Nest predation is the primary cause of nest failure in most ground‐nesting bird species. Investigations of relationships between nest predation rate and habitat usually pool different predator species. However, such relationships likely depend on the specific predator involved, partly because habitat requirements vary among predator species. Pooling may therefore impair our ability to identify conservation‐relevant relationships between nest predation rate and habitat. We investigated predator‐specific nest predation rates in the forest‐dependent, ground‐nesting wood warbler Phylloscopus sibilatrix in relation to forest area and forest edge complexity at two spatial scales and to the composition of the adjacent habitat matrix. We used camera traps at 559 nests to identify nest predators in five study regions across Europe. When analyzing predation data pooled across predator species, nest predation rate was positively related to forest area at the local scale (1000 m around nest), and higher where proportion of grassland in the adjacent habitat matrix was high but arable land low. Analyses by each predator species revealed variable relationships between nest predation rates and habitat. At the local scale, nest predation by most predators was higher where forest area was large. At the landscape scale (10,000 m around nest), nest predation by buzzards Buteo buteo was high where forest area was small. Predation by pine martens Martes martes was high where edge complexity at the landscape scale was high. Predation by badgers Meles meles was high where the matrix had much grassland but little arable land. Our results suggest that relationships between nest predation rates and habitat can depend on the predator species involved and may differ from analyses disregarding predator identity. Predator‐specific nest predation rates, and their relationships to habitat at different spatial scales, should be considered when assessing the impact of habitat change on avian nesting success.

Recent changes in the reproductive success of farmland birds: conservation and management implications. The declining grey partridge Perdix perdix as a case study

Several ground-nesting bird species living in European farmlands are experiencing a persistent decline. Poorer reproductive success is suspected to be the main demographic driver. We developed a model to quantify to what extent such recent change may impact the viability of their populations. We took the grey partridge Perdix perdix, a typical farmland species, as a well-documented case study, but the model can be adapted to other species. We built a model based on our in-depth demographic knowledge of this species and the large database compiled from our long-term population monitoring programme. We took into account environmental and demographic stochasticity as well as density-dependence processes. We investigated the impact of recent changes in reproductive success on the viability of (unharvested) populations. For this purpose, we considered two periods: 1979–2004 as ‘Past’ and 2005–2014 as ‘Present’ (we used data of subsequent years to test the model’s goodness of fit). During the ‘Past’ period, the simulated population was increasing with a mean stochastic growth rate λmean = 1.01 (25% of decreasing trajectories), whereas λmean = 0.89 during the ‘Present’ period (74% of decreasing trajectories). We provide detailed results and discuss the possible environmental causes, with a focus on extreme weather events. In a further step, we used our model as a tool to investigate the impact of four hunting bag management strategies on exploited populations. The hunting bag was assumed to be an additive cause of mortality. Hunting leads to a decrease in λmean but the amplitude (from minor to substantial) depends upon the strategy and the setting-up of parameters. We deliver our model as a tool to support decision-making for sustainable population management and provide the script (ULM software) as Supplementary information.

Reducing nest predation of ground-nesting birds through conditioned food aversion

Populations of many ground-nesting bird species have declined substantially due to several factors, and predation can be a leading contributor to these declines. As a method for reducing the nest predation on ground-nesting birds, we tested whether conditioned food aversion (CFA) can reduce red-legged partridge (Alectoris rufa) nest predation by red foxes (Vulpes vulpes). With a before-after control-impact design we deployed 1329 artificial nests in two different habitats in Central Spain using thiram as an aversive. Artificial nests were monitored by camera traps to identify the red fox individuals during the predation events. 26 foxes were GPS-tagged to monitor their spatial movements and feeding behavior. Partridge density and productivity were monitored to assess the thiram treatment effect on partridge population. Thiram treatment decreased artificial nest predation by foxes in both study sites by 26.8–50.1%, but this was compensated by an increased predation by other predators, possibly enhanced by the availability of our artificial nests. 78% of identified foxes that ingested thiram-treated eggs, stopped nest predation after treatment. Foxes maintained stable territories during the whole study period. Partridge productivity was 132–677% higher in thiram-treatment areas than in control areas, and partridge density after treatment increased more in thiram-treated areas (193–292%) than in control areas (1.8–99%). Our study shows that CFA reduced ground nest predation by foxes, and had a positive effect on the partridge population despite the compensatory predation. This method could be used as a non-lethal tool for conservation of endangered ground-nesting bird species.

Age-dependent survival rate of the colonial Little Tern (Sternula albifrons).

Many ground-nesting bird species are suffering from habitat loss and population decline. Data on population ecology and demography in colonies of threatened species are thus essential for designing effective conservation protocols. Here, we used extensive ringing and observation data to estimate directly, for the first time, the survival rate of juvenile and adult Little Tern (Sternula albifrons), as well as testing for a possible effect of age on probability of survival. We estimated adult annual survival rate to be 0.77, and juvenile (first year) survival to be 0.49 with a possible linear decrease in the survival rate of the juveniles that ranged from 0.681 to 0.327. We found no evidence that survival was age-dependent among the early age classes after the first year. We discuss these findings in light of survival estimates for other species, and their implications for the Little Tern conservation.

Opportunistic Predation of Wild Turkey Nests by Wild Pigs

ABSTRACTWild pigs (Sus scrofa; i.e., feral hogs, feral swine) are considered an invasive species in the United States. Where they occur, they damage agricultural crops and wildlife habitat. Wild pigs also depredate native wildlife, particularly ground‐nesting bird species during nesting season. In areas inhabited by wild turkeys (Meleagris gallopavo), nest destruction caused by wild pigs may affect recruitment. There is debate whether wild pigs actively seek ground‐nesting bird nests or depredate them opportunistically. To address this debate, in 2016 we examined the movements of wild pigs relative to artificial wild turkey nests (i.e., control [no artificial nests], moderate density [12.5–25 nests/km2], and high density [25–50 nests/km2]) throughout the nesting season (i.e., early, peak, and late) in south‐central Texas, USA. We found no evidence that wild pigs learned to seek and depredate wild turkey nests relative to nest density or nesting periods. Despite wild pigs being important nest predators, depredation was not a functional response to a pulsed food resource and can only be associated with overlapping densities of wild pigs and nests. Protecting reproductive success of wild turkeys will require reducing wild pig densities in nesting habitat prior to nesting season. © 2019 The Wildlife Society.

Meadow Birds at the Waning Traditional Pasture Animal Husbandry

Журнал принимает на русском и английском языках статьи, представляющие результаты научных исследований в различных областях теоретической и прикладной экологии. Приоритет отдается научным статьям, основанным на явно сформулированных гипотезах.

Common Terns Sterna hirundo incubating Common Garden Snail shells Helix aspersa on Rockabill Island

Many ground-nesting bird species have been observed incubating foreign objects in their nests (Mellink 2002). Pine cones, golf balls, guano, hermit crabs, mammalian bones and many more objects have all been recorded in bird nests (Knight & Erickson 1977; Mellink 2002; Langlois et al. 2012). A study by Conover (1985) showed that 10% of Ring-billed Gull Larus delawarensis and 6% of California Gull L. californicus nests contained a foreign object. These foreign objects were more similar in size and shape to the gull eggs than to randomly selected pebbles. Little Terns Sterna albifrons have been observed incubating egg-like pebbles for several weeks on two separate occasions at a breeding colony in Kilcoole, Co. Wicklow, Ireland (Farrelly 1990). Several hypotheses have been put forward to explain this behaviour. Coulter (1980) suggested that foreign objects may act as an incubation stimulus. Many tern and gull species, unlike other birds, have three brood patches not one (Gochfeld 1976; Reid 1987). Coulter (1980) conducted incubation studies of several species of gulls suggesting that birds incubating three eggs sat for longer periods of time, resettled less frequently, have a shorter incubation period and a higher hatching success than birds on either fewer eggs or more. He speculated that gulls are highly adapted for three-egg clutches whereby the foreign objects provide an important stimulus for incubation behaviour when there are less than three eggs (Beer 1961; Beer 1965; Baerends et al. 1970; Coulter 1980). Alternatively, the mistaken-food hypothesis suggests that a predatory bird brings a foreign object back to the nest, regurgitates the object and then proceeds to incubate it, mistaking it for one of its own eggs (Sugden 1947; Twomey 1948). A third hypothesis is that the foreign object is mistaken by the bird for one of its own eggs and rolled into the nest, in this scenario the foreign object is likely to have originated from close to the nest (Conover 1985).

Importance of Old Forest Stands for Diversity of Birds in Managed Pine Forests – A Case Study from Augustów Forest (NE Poland)

We assessed the assemblages of birds inhabiting pine-dominated managed forest, aged between 1–5 years and above 140 years. Birds were counted on study plots representing eight different phases to the forest's development, with nesting, foraging and migratory guild categories recognised. Numbers of bird species and population densities, both increased markedly with stand age (respectively r = 0.988 and r = 0.936, P < 0.001). While numbers of ground-nesting bird species failed to correlate with stand age, successively older stands did support ever-greater proportions of species in the assemblage that nested in tree crowns (r = 0.976, P < 0.005) or tree holes (r = 0.833, P < 0.005). Raptors were most abundant in forest at the oldest stages of growth, and there was an age-gradient-related increase in the shares of both plant-eating species (r = 0.952, P < 0.005) and raptors (r = 0.764, P < 0.005). Resident birds were most numerous in the oldest forest. PCA for ten selected variables (relating to guild type) showed that the two principal components explained almost 98% of the variation among groups of bird guilds in relation to forest age. On the basis of their suitability for birds it was possible to distinguish three categories of stand by age group, of which the first encompasses the initial stage, the second a broad interval involving middle-aged stands of between 16 and 140 years, and the third forest more than 140 years old. The presence of the oldest stands of all can thus be seen to play a very important role in maintaining high-diversity populations of birds in managed forest.

Reproductive plasticity and landscape heterogeneity benefit a ground-nesting bird in a fire-prone ecosystem.

Disturbance is critical for the conservation of rangeland ecosystems worldwide and many of these systems are fire dependent. Although it is well established that restoring fire as an ecological process can lead to increased biodiversity in grasslands and shrublands, the underlying mechanisms driving community patterns are poorly understood for fauna in fire-prone landscapes. Much of this uncertainty stems from the paucity of studies that examine the effects of fire at scales relevant to organism life histories. We assessed the response of a non-migratory ground-dwelling bird to disturbance (i.e., prescribed fire) and environmental stochasticity over the course of a 4-yr period, which spanned years of historic drought and record rainfall. Specifically, we investigated the nesting ecology of Northern Bobwhite (Colinus virginianus; hereafter Bobwhite) to illuminate possible avenues by which individuals respond to dynamic landscape patterns during a critical reproductive stage (i.e., nesting) in a mixed-grass shrubland in western Oklahoma, USA. We found that Bobwhites exhibited extreme plasticity in nest substrate use among time since fire categories (TSF) and subsequently maintained high nest survival (e.g., 57-70%). Bobwhites were opportunistic in nest substrate use among TSF categories (i.e., 72% of nest sites in shrubs in 0-12months post fire compared to 71% in herbaceous vegetation in >36months post fire), yet nesting decisions were first filtered by similar structural components (i.e., vertical and horizontal cover) within the vicinity of nest sites regardless of TSF category. Despite being a non-migratory and comparatively less mobile ground-nesting bird species, Bobwhites adjusted to dynamic vegetation mosaics on a fire-prone landscape under stochastic climatic conditions that culminated in stable and high nest survival. Broadly, our findings provide a unique depiction of organism response strategies to fire at scales relevant to a critical life-stage, a topic that has been previously understudied and poorly understood. We also demonstrate how doing so can better inform conservation practices aimed at restoring fire regimes on grassland and shrubland landscapes.

What Does the Eggshell Cuticle Do? A Functional Comparison of Avian Eggshell Cuticles.

The avian eggshell is a highly ordered structure with several layers (mammillae, palisades, and vertical crystal layer) composed of calcium carbonate (∼96%) and minerals within an organic matrix. The cuticle is a noncalcified layer that covers the eggshells of most bird species. Eggshells are multifunctional structures that have evolved in response to diverse embryonic requirements and challenges, including protection from microbial infection, nest flooding, and exposure to solar radiation. However, experimental evidence for these functions across diverse taxa is currently limited. Here we investigated the effects of nanosphere cuticles on (1) bacterial attachment and transshell penetration, (2) eggshell wettability, (3) water vapor conductance, and (4) regulation of ultraviolet (UV) reflectance in seven ground-nesting bird species. We found considerable interspecific variation in ultrastructure and chemical composition of cuticles. Experimental removal of the cuticle confirmed that all nanospheres were highly effective at decreasing attachment of bacteria to shell surfaces and at preventing bacterial penetration. Cuticles also greatly decreased the amount of UV reflected by eggshells. In species with particularly small nanospheres, gas exchange was reduced by the presence of cuticle. Our results support the hypothesis that microbes and solar UV radiation can cause strong selection on bird eggs but also show that we need a greater understanding about the effects of specific nesting conditions (e.g., hydric and gaseous milieu) on embryo well-being and eggshell structure variation.

Improvement of individual camouflage through background choice in ground-nesting birds.

Animal camouflage is a longstanding example of adaptation. Much research has tested how camouflage prevents detection and recognition, largely focusing on changes to an animal's own appearance over evolution. However, animals could also substantially alter their camouflage by behaviourally choosing appropriate substrates. Recent studies suggest that individuals from several animal taxa could select backgrounds or positions to improve concealment. Here, we test whether individual wild animals choose backgrounds in complex environments, and whether this improves camouflage against predator vision. We studied nest site selection by nine species of ground-nesting birds (nightjars, plovers and coursers) in Zambia, and used image analysis and vision modeling to quantify egg and plumage camouflage to predator vision. Individual birds chose backgrounds that enhanced their camouflage, being better matched to their chosen backgrounds than to other potential backgrounds with respect to multiple aspects of camouflage. This occurred at all three spatial scales tested (a few cm and five meters from the nest, and compared to other sites chosen by conspecifics), and was the case for the eggs of all bird groups studied, and for adult nightjar plumage. Thus, individual wild animals improve their camouflage through active background choice, with choices highly refined across multiple spatial scales.

The role of nest‐site selection and cereal production in differential nest predation in Common Quail Coturnix coturnix and hybrid quail C. coturnix × C. japonica

In Europe, farm‐reared quail used for restocking purposes are often hybrids between the Common Quail Coturnix coturnix and the Japanese Quail Coturnix japonica. These hybrids interbreed with wild Common Quail populations and suffer higher rates of nest predation, which would suggest that the two quail types have different nest‐site selection patterns. We monitored 103 radiotagged nesting females (77 wild Common Quail over 18 breeding seasons and 26 hybrid quail over six breeding seasons) and analysed their nest placement behaviour. Our results did not provide any evidence that the quail types showed different nest‐site selection trends, as they all preferred to nest near cereal field margins. The higher nest predation rate experienced by hybrids might therefore be explained by less effective anti‐predator behaviour among hybrid females during incubation. As no edge effect on nest predation was observed, the preference for nesting close to cereal margins could be due to the greater food resources of field margins. Moreover, Common Quail nest predation decreased with a rise in barley straw production, supporting evidence that nest cover plays an important role in the prevention of nest predation in this species. No such relationship was found for hybrid quail, but this result is not conclusive, as the data on barley straw production for hybrid quail covered a much smaller range of interannual variability. Barley straw production in Catalonia decreased significantly between 1992 and 2012, possibly as a result of a change in the barley varieties used. This practice could entail a conservation threat for ground‐nesting bird species.

A Ground-Nesting Galliform's Response to Thermal Heterogeneity: Implications for Ground-Dwelling Birds.

The habitat selection choices that individuals make in response to thermal environments influence both survival and reproduction. Importantly, the way that organisms behaviorally respond to thermal environments depends on the availability and juxtaposition of sites affording tolerable or preferred microclimates. Although, ground nesting birds are especially susceptible to heat extremes across many reproductive stages (i.e., breeding, nesting, brood rearing), the mechanistic drivers of nest site selection for these species are not well established from a thermal perspective. Our goal was to assess nest site selection relative to the configuration of the thermal landscape by quantifying thermal environments available to a ground-nesting bird species inhabiting a climatically stressful environment. Using northern bobwhite (Colinus virginanus) as a model species, we measured black bulb temperature (Tbb) and vegetation parameters at 87 nests, 87 paired sites and 205 random landscape sites in Western Oklahoma during spring and summer 2013 and 2014. We found that thermal space within the study area exhibited differences in Tbb of up to 40°C during peak diurnal heating, resulting in a diverse thermal landscape available to ground-nesting birds. Within this thermally heterogeneous landscape, nest sites moderated Tbb by more than 12°C compared to random landscape sites. Furthermore, successful nests remained on average 6°C cooler than unsuccessful nests on days experiencing ambient temperatures ≥ 39°C. Models of future Tbb associated with 2080 climate change projections indicate that nesting bobwhites will face substantially greater Tbb throughout the landscape for longer durations, placing an even greater importance on thermal choices for nest sites in the future. These results highlight the capacity of landscape features to act as moderators of thermal extremes and demonstrate how thermal complexity at organism-specific scales can dictate habitat selection.

Local habitat and landscape influence predation of bird nests on afforested Mediterranean cropland

Afforestation programs such as the one promoted by the EU Common Agrarian Policy have contributed to spread tree plantations on former cropland. Nevertheless these afforestations may cause severe damage to open habitat species, especially birds of high conservation value. We investigated predation of artificial bird nests at young tree plantations and at the open farmland habitat adjacent to the tree plantations in central Spain. Predation rates were very high at both tree plantations (95.6%) and open farmland habitat (94.2%) after two and three week exposure. Plantation edge/area ratio and development of the tree canopy decreased predation rates and plantation area and magpie (Pica pica) abundance increased predation rates within tree plantations, which were also affected by land use types around plantations. The area of nearby tree plantations (positive effect), distance to the tree plantation edge (negative effect), and habitat type (mainly attributable to the location of nests in vineyards) explained predation rates at open farmland habitat. We conclude that predation rates on artificial nests were particularly high and rapid at or nearby large plantations, with high numbers of magpies and low tree development, and located in homogenous landscapes dominated by herbaceous crops and pastures with no remnants of semi-natural woody vegetation. Landscape planning should not favour tree plantations as the ones studied here in Mediterranean agricultural areas that are highly valuable for ground-nesting bird species.

Predation on the eggs of ground-nesting birds by Dasypeltis scabra (Linnaeus, 1758) in the moist highland grasslands of South Africa

We provide evidence for predation by the Common Egg-eater (Dasypeltis scabra) on the eggs of three species of ground-nesting birds, namely African Pipit (Anthus cinnamomeus), Cape Longclaw (Macronyx capensis) and Common Quail (Coturnix coturnix). Although egg-eaters have been recorded as egg predators of several bird species in the wild – including a few other ground-nesters such as lapwings, francolins, sandgrouse, gulls and terns – we present the first evidence of such predation in the Mesic Highveld Grassland Bioregion of South Africa.

Automatic Detection of Animals in Mowing Operations Using Thermal Cameras

During the last decades, high-efficiency farming equipment has been developed in the agricultural sector. This has also included efficiency improvement of moving techniques, which include increased working speeds and widths. Therefore, the risk of wild animals being accidentally injured or killed during routine farming operations has increased dramatically over the years. In particular, the nests of ground nesting bird species like grey partridge (Perdix perdix) or pheasant (Phasianus colchicus) are vulnerable to farming operations in their breeding habitat, whereas in mammals, the natural instinct of e.g., leverets of brown hare (Lepus europaeus) and fawns of roe deer (Capreolus capreolus) to lay low and still in the vegetation to avoid predators increase their risk of being killed or injured in farming operations. Various methods and approaches have been used to reduce wildlife mortality resulting from farming operations. However, since wildlife-friendly farming often results in lower efficiency, attempts have been made to develop automatic systems capable of detecting wild animals in the crop. Here we assessed the suitability of thermal imaging in combination with digital image processing to automatically detect a chicken (Gallus domesticus) and a rabbit (Oryctolagus cuniculus) in a grassland habitat. Throughout the different test scenarios, our study animals were detected with a high precision, although the most dense grass cover reduced the detection rate. We conclude that thermal imaging and digital imaging processing may be an important tool for the improvement of wildlife-friendly farming practices in the future.