I studied aspects of the ecology of the Murray River turtle, Emydura macquarii, to determine the impact of the introduced red fox, Vulpes vulpes. The fox is one of Australia's worst vertebrate pests through its predation on livestock and native mammals, but their impact on reptilian communities is not known. I conducted a large-scale mark-recapture study to evaluate population growth of E. macquarii in the Albury region of the upper Murray River by determining growth, reproduction and survival. The study was conducted downstream of the first, and largest, impoundment on the Murray River, Lake Hume. Emydura macquarii predominantly inhabit the lagoons in the upper Murray River, as the mainstream and Lake are possibly too cool to maintain metabolic processes. They are easily captured in hoop traps and the use of live decoys maximises trap success. Over 2000 hatchling turtles were marked and released into two lagoons between January 1997 and January 1998. Growth of these individuals is rapid over the first few years but declines towards maturity, and is indeterminate after maturity. Although growth annuli are not well defined, even on young individuals, the von Bertalanffy model describes the growth of both male and female E. macquarii. Male turtles mature at 5-6 years and females mature at 10-12 years. Female turtles may maximise reproductive potential by delaying maturity and producing one relatively large clutch (mean = 21 eggs) per year, which is positively correlated with body size (PL). Although primarily related to body size, clutch size varies annually because of environmental conditions. If winter and summer rainfalls are below average and temperatures are above average, E. macquarii may reduce clutch size to increase the chance of the eggs surviving. Nesting predominantly occurs during the first major rain-bearing depression in November. Habitat variables, including distance from water, nearest nest, and tree, and soil type were measured for each nest to determine characteristics that attract predators. Nests close to the shoreline and trees are heavily preyed on, and nests constructed in sand are less likely to be destroyed by predators. Foxes detect nests through a combination of chemical cues from eggs and slight soil disturbances, whereas birds only destroy nests observed being constructed during the day. Female turtles alter nesting behaviour and construct nests much further away from water when foxes were removed and as a result, nests are less dense and away from trees. Thus in high predation risk areas, turtles minimise emergence and search times to reduce the risk of direct predation by foxes. Predation is reduced when nests are in lower densities and away from trees, because predators increase search efforts when nests are in higher densities and birds are more likely to destroy nests close to trees. Reproductive success is further reduced in high predation risk areas because more nests are constructed in sandy substrates where clutch success is reduced compared to incubation in more dense substrates. Where predators are a significant source of mortality, prey may use indirect methods, such as chemical recognition, to avoid encounters. Nesting turtles did not avoid areas where fox odour was present, suggesting that they assess predation pressure from foxes by other mechanisms, such as visual recognition. However, an innate response occurs to the odour of a once common predator on the Murray River, the eastern quoll (Dasyurus viverrinus), whereby turtles recognise and avoid nesting in areas where quoll odour is present. Therefore nesting turtles show a similar avoidance response to two different predators, using different mechanisms of detection. Similarly, predation risk may influence hatching times and nest emergence. The rate of embryonic development of E. macquarii may increase or eggs may hatch early so that the clutch hatches synchronously, thereby reducing the risk of predation through group emergence from the nest. Emydura macquarii reach densities of over 100 turtles.ha-1, with the majority of the population consisting of sexually mature individuals. Emydura macquarii has a Type III survival curve where mortality is extremely high in the egg stage (93% nest predation), remaining high over the hatchling stage (minimum survival rate- 10%), but decreasing rapidly throughout the juvenile stage (~70% juvenile survival). Adult survival is extremely high, with greater than 95% of adults surviving each year. Foxes through nest predation cause most mortality but a small proportion (~3%) of nesting adult females are killed by foxes each year. A removal program evaluated the impact of foxes. In 1996, fox numbers were monitored around four lagoons by spotlighting and non-toxic bait uptake. Foxes were removed from around two of the lagoons throughout 1997 and 1998, using spotlight shooting and 1080 bait poisoning. Fox numbers were continually monitored around all four lagoons during the study. Nest predation rates remained around 90% in all sites where foxes were present, but fell to less than 50% when foxes were removed. At the same time, predation on nesting female turtles was eliminated where foxes were removed. Demographic models using staged based survival schedules, together with growth and fecundity values for E. macquarii show a decline of 4% per year in these populations. Elasticity analyses shows that survival of adult female E. macquarii has the major influence on population stability and a reduction of nest predation alone is unlikely to address the population decline. Management options, such as reducing foxes prior to nesting around key lagoons, will stabilise the population decline, and eliminating foxes completely from certain areas with high dispersal potential, will promote recruitment of juvenile E. macquarii.

L'échinococcose alvéolaire, qui peut être fatale si le diagnostic est tardif, est une zoonose émergente. Elle est due à un cestode, Echinococcus multilocularis, dont le cycle fait intervenir le renard roux, Vulpes vulpes, comme hôte définitif et les campagnols prairiaux (Microtus arvalis et Arvicola terrestris) comme hôtes intermédiaires. Relativement peu de données sont actuellement disponibles sur les facteurs écologiques qui peuvent moduler l'intensité de la transmission du parasite entre ses hôtes aux fenêtres d'observation régionales et locales. Dans ce contexte, nous avons conduit une étude du fonctionnement du cycle d'Em à différents niveaux de perception, dans le département français des Ardennes, considéré comme une région de nouvelle endémie. La prévalence vulpine, estimée à 53 % pourrait être expliquée par une densité relativement élevée de renards et une importante consommation de M. arvalis de leur part. A une étendue régionale (900 km²) et un grain local (1 km²), la prévalence vulpine et la distribution des charges parasitaires apparaissent très hétérogènes, avec un gradient croissant nord-sud très marqué. La majorité de la biomasse parasitaire est concentrée sur quelques individus et sur quelques kilomètres carrés. Les caractéristiques du paysage et les densités de rongeurs hôtes intermédiaires semblent influencer les prévalences vulpines. Enfin, à une étendue locale (90 km²) et un grain micro-local (1000 m²), les lisières semblent particulièrement favorables à la transmission parasitaire, puisque c'est dans ce milieu que coïncident des densités élevées de fèces de renards et de rongeurs et, donc, que les contacts entre oeufs et hôtes intermédiaires sont les plus probables.

<p>The genetic basis for behavioural traits is largely unknown. The overall aim of this thesis was to find genes with importance for behavioural traits related to fear and anxiety. Microarray analysis was used to screen expression profiles of brain regions important for emotional behaviour in dogs, wolves, foxes and mice. In a first experiment, dogs and their wild ancestors the wolves were compared. Our results suggested that directed selection for behaviour might have resulted in expression changes in few genes acting on several brain functions, possibly affecting behaviour. However, the observed expressional differences were confounded with environmental effects. This was addressed in a second study on domesticated silver foxes. By correlating behaviour and brain gene expression in foxes selected for tameness to non-selected foxes raised in the same environment, we found large behavioural differences but only few genes with differential expression in the brain. Fifteen of the 40 genes showing evidence of expression difference were related to haem or haemoglobins. Further studies showed an additive genetic effect on brain gene expression, similar to the additive genetic inheritance of behaviour, indicating an involvement in domestication. Transcriptional profiling was also used for finding genes involved with the sleep disorder narcolepsy. Narcoleptic Doberman pinschers homozygous for the canarc-1 mutation were compared to their unaffected heterozygots revealing reduced expression of three genes, TAC1, PENK and SOCS2, with relevance to the narcoleptic phenotype. Finally gene expression was investigated in relation to anxiety-related traits in a mouse model. Surprisingly, as in the fox study, genes coding for haemoglobins indicated differential expression in the brain between animals with different anxiety levels. Our combined results suggest that genes like haemoglobins, best known for their function in oxygen transport in blood, may also participate in brain functions related to decreased anxiety in domestic animals. </p>

The genetic basis for behavioural traits is largely unknown. The overall aim of this thesis was to find genes with importance for behavioural traits related to fear and anxiety. Microarray analysis was used to screen expression profiles of brain regions important for emotional behaviour in dogs, wolves, foxes and mice. In a first experiment, dogs and their wild ancestors the wolves were compared. Our results suggested that directed selection for behaviour might have resulted in expression changes in few genes acting on several brain functions, possibly affecting behaviour. However, the observed expressional differences were confounded with environmental effects. This was addressed in a second study on domesticated silver foxes. By correlating behaviour and brain gene expression in foxes selected for tameness to non-selected foxes raised in the same environment, we found large behavioural differences but only few genes with differential expression in the brain. Fifteen of the 40 genes showing evidence of expression difference were related to haem or haemoglobins. Further studies showed an additive genetic effect on brain gene expression, similar to the additive genetic inheritance of behaviour, indicating an involvement in domestication. Transcriptional profiling was also used for finding genes involved with the sleep disorder narcolepsy. Narcoleptic Doberman pinschers homozygous for the canarc-1 mutation were compared to their unaffected heterozygots revealing reduced expression of three genes, TAC1, PENK and SOCS2, with relevance to the narcoleptic phenotype. Finally gene expression was investigated in relation to anxiety-related traits in a mouse model. Surprisingly, as in the fox study, genes coding for haemoglobins indicated differential expression in the brain between animals with different anxiety levels. Our combined results suggest that genes like haemoglobins, best known for their function in oxygen transport in blood, may also participate in brain functions related to decreased anxiety in domestic animals.

I studied aspects of the ecology of the Murray River turtle, Emydura macquarii, to determine the impact of the introduced red fox, Vulpes vulpes. The fox is one of Australia's worst vertebrate pests through its predation on livestock and native mammals, but their impact on reptilian communities is not known. I conducted a large-scale mark-recapture study to evaluate population growth of E. macquarii in the Albury region of the upper Murray River by determining growth, reproduction and survival. The study was conducted downstream of the first, and largest, impoundment on the Murray River, Lake Hume. Emydura macquarii predominantly inhabit the lagoons in the upper Murray River, as the mainstream and Lake are possibly too cool to maintain metabolic processes. They are easily captured in hoop traps and the use of live decoys maximises trap success. Over 2000 hatchling turtles were marked and released into two lagoons between January 1997 and January 1998. Growth of these individuals is rapid over the first few years but declines towards maturity, and is indeterminate after maturity. Although growth annuli are not well defined, even on young individuals, the von Bertalanffy model describes the growth of both male and female E. macquarii. Male turtles mature at 5-6 years and females mature at 10-12 years. Female turtles may maximise reproductive potential by delaying maturity and producing one relatively large clutch (mean = 21 eggs) per year, which is positively correlated with body size (PL). Although primarily related to body size, clutch size varies annually because of environmental conditions. If winter and summer rainfalls are below average and temperatures are above average, E. macquarii may reduce clutch size to increase the chance of the eggs surviving. Nesting predominantly occurs during the first major rain-bearing depression in November. Habitat variables, including distance from water, nearest nest, and tree, and soil type were measured for each nest to determine characteristics that attract predators. Nests close to the shoreline and trees are heavily preyed on, and nests constructed in sand are less likely to be destroyed by predators. Foxes detect nests through a combination of chemical cues from eggs and slight soil disturbances, whereas birds only destroy nests observed being constructed during the day. Female turtles alter nesting behaviour and construct nests much further away from water when foxes were removed and as a result, nests are less dense and away from trees. Thus in high predation risk areas, turtles minimise emergence and search times to reduce the risk of direct predation by foxes. Predation is reduced when nests are in lower densities and away from trees, because predators increase search efforts when nests are in higher densities and birds are more likely to destroy nests close to trees. Reproductive success is further reduced in high predation risk areas because more nests are constructed in sandy substrates where clutch success is reduced compared to incubation in more dense substrates. Where predators are a significant source of mortality, prey may use indirect methods, such as chemical recognition, to avoid encounters. Nesting turtles did not avoid areas where fox odour was present, suggesting that they assess predation pressure from foxes by other mechanisms, such as visual recognition. However, an innate response occurs to the odour of a once common predator on the Murray River, the eastern quoll (Dasyurus viverrinus), whereby turtles recognise and avoid nesting in areas where quoll odour is present. Therefore nesting turtles show a similar avoidance response to two different predators, using different mechanisms of detection. Similarly, predation risk may influence hatching times and nest emergence. The rate of embryonic development of E. macquarii may increase or eggs may hatch early so that the clutch hatches synchronously, thereby reducing the risk of predation through group emergence from the nest. Emydura macquarii reach densities of over 100 turtles.ha-1, with the majority of the population consisting of sexually mature individuals. Emydura macquarii has a Type III survival curve where mortality is extremely high in the egg stage (93% nest predation), remaining high over the hatchling stage (minimum survival rate- 10%), but decreasing rapidly throughout the juvenile stage (~70% juvenile survival). Adult survival is extremely high, with greater than 95% of adults surviving each year. Foxes through nest predation cause most mortality but a small proportion (~3%) of nesting adult females are killed by foxes each year. A removal program evaluated the impact of foxes. In 1996, fox numbers were monitored around four lagoons by spotlighting and non-toxic bait uptake. Foxes were removed from around two of the lagoons throughout 1997 and 1998, using spotlight shooting and 1080 bait poisoning. Fox numbers were continually monitored around all four lagoons during the study. Nest predation rates remained around 90% in all sites where foxes were present, but fell to less than 50% when foxes were removed. At the same time, predation on nesting female turtles was eliminated where foxes were removed. Demographic models using staged based survival schedules, together with growth and fecundity values for E. macquarii show a decline of 4% per year in these populations. Elasticity analyses shows that survival of adult female E. macquarii has the major influence on population stability and a reduction of nest predation alone is unlikely to address the population decline. Management options, such as reducing foxes prior to nesting around key lagoons, will stabilise the population decline, and eliminating foxes completely from certain areas with high dispersal potential, will promote recruitment of juvenile E. macquarii.

The piping plover (Charadrius melodus) is a federally-listed shorebird that nests on barrier islands along the U.S. Atlantic Coast and is highly vulnerable to habitat change and predation. We have addressed these two threats by 1) developing and implementing a linked model system that predicts future change to piping plover habitat resulting from sea-level rise and beach management efforts by joining dynamic models of sea-level rise, shoreline change, island geomorphology and piping plover nest habitat suitability, and 2) quantifying occupancy and movement of the red fox (Vulpes vulpes), a key shorebird predator at Assateague Island, Maryland and Virginia. We constructed and tested a model that links changes in geomorphological characteristics to piping plover nesting habitat suitability. We then linked this model to larger scale shoreline change resulting from sea level rise and storms. Using this linked model to forecast future sea-level rise and beach management efforts, we found that modest sea-level rise rates (3 mm and 4.1 mm/yr; similar to current rates) may increase suitable piping plover nesting habitat area in 50-100 years and some beach management strategies (beach nourishment and artificial dune modifications) also influence habitat availability. Our development and implementation of this tool to predict change in piping plover habitat suitability provides a vital starting point for predicting how plover nesting habitat will change in a context of planned human modifications intended to address climate change-related threats. Our findings regarding red fox occupancy and movement complement the use of this model for planning future management actions by providing vital information on the effects of certain predator management activities and habitat use of a key mammalian predator, the red fox, for shorebirds along the U.S. Atlantic Coast. Overall, we found that 1) red fox occupancy was strongly tied to eastern cottontail (Sylvilagus floridanus) trap success, increasing sharply with increased eastern cottontail trap success, 2) red fox occupancy did not change in response to an intensive eradication program, and 3) red foxes in our study area generally moved little between camera stations spaced 300 m from each other, but may move large distances (> 6km) at times, likely to occupy new territory available after lethal control efforts. Our findings have important ramifications for the sustainability of long-term predator removal programs and our understanding of future habitat change on the red fox. For example how vegetation changes affect eastern cottontails, how resulting fluctuations in eastern cottontails affect red fox occupancy, and how consequential changes in red fox occupancy affect plover breeding productivity. Our predictive model combined with these predator findings will allow wildlife managers to better plan and implement effective management actions for piping plovers in response to the multiple stressors of SLR-induced habitat change and predation. / Ph. D.

When new populations are first identified in a region there are multiple potential sources: introduction of a non-native species, extra-range expansion of a nearby population, or demographic growth of a previously unnoticed species. Red foxes were absent or rare in the mid-eastern portion United States until the late 1800s. Their origins potentially include natural population increase/expansion, translocations from Europe, and, eventually, 20th century fur farming. In this study I attempt to identify the relative impact of native expansion versus human mediated introductions of both colonial era European foxes and early 20th century fur-farm foxes on the establishment of red foxes in the mid-Atlantic region of the United States. I subsequently address the potential impacts of hybridization and nuclear introgression between previously separate sister taxa. Through analysis of mitochondrial DNA, I identified indigenous haplotypes, two European haplotypes, and fur-farm haplotypes; another set of haplotypes were potentially indigenous or native. In addition, I found European Y-chromosome haplotypes. Most European and fur-farm haplotypes were found near the densely human-populated coastal plain and Hudson River lowlands; most red foxes of the Appalachians and Piedmont had native eastern haplotypes. However, nuclear data does not support this division showing low genetic structure despite the broad geographic scale of our study area, attributable both to range expansion and admixture. Admixture has not had the same impact on the nuclear genome as it has in mitochondrial haplotypes leading to mito-nuclear discordance across the region. I also found evidence for differential patterns of expansion related to habitat. Specifically, the Appalachian Mountains acted as a corridor for gene flow from the northern native source into the southern Mid-Atlantic region

Inflammation in meninges and/or brain is regularly noticed in red foxes and other wild carnivores during rabies control programs. Despite negative rabies virus (RABV) results, the etiologies of these cases remain unknown. Thus, the aim of this study was to provide an overview of the occurrence of pathogens that may cause diseases in the brains of wild carnivores and pose a risk to humans and other animals. In addition to RABV and canine distemper virus (CDV), a variety of pathogens, including members of Flaviviridae, Bornaviridae, Herpesviridae, Circoviridae, as well as bacteria and parasites can also cause brain lesions. In 2016 and 2017, brain samples of 1,124 wild carnivores were examined by direct fluorescent antibody test for RABV as well as (reverse-transcriptase) quantitative polymerase chain reaction (PCR) for the presence of CDV as part of a monitoring program in Saxony-Anhalt, Germany. Here, we applied similar methods to specifically detect suid herpesvirus 1 (SuHV-1), West Nile virus (WNV), Borna disease virus 1 (BoDV-1), canid alphaherpesvirus 1 (CaHV-1), canine parvovirus type 2 (CPV-2), fox circovirus (FoxCV), and Neospora caninum (N. caninum). Further, bacteriogical examination for the existence of Listeria monocytogenes (L. monocytogenes) and immunohistochemistry of selected cases to detect Toxoplasma gondii (T. gondii) antigen were performed. Of all pathogens studied, CDV was found most frequently (31.05%), followed by FoxCV (6.80%), CPV-2 (6.41%), T. gondii (4/15; 26.67%), nematode larvae (1.51%), L. monocytogenes (0.3%), and various other bacterial pathogens (1.42%). In 68 of these cases (6.05%), multiple pathogen combinations were present simultaneously. However, RABV, WNV, BoDV-1, SuHV-1, CaHV-1, and N. caninum were not detected. The majority of the histopathological changes in 440 animals were inflammation (320/440; 72.73%), predominantly non-suppurative in character (280/320; 87.50%), and in many cases in combination with gliosis, satellitosis, neuronophagia, neuronal necrosis, and/or vacuolization/demyelination, or in single cases with malacia. Thus, it could be shown that wild carnivores in Saxony-Anhalt are carriers mainly for CDV and sometimes also for other, partly zoonotic pathogens. Therefore, the existing monitoring program should be expanded to assess the spill-over risk from wild carnivores to humans and other animals and to demonstrate the role of wild carnivores in the epidemiology of these zoonotic pathogens.

Landscape change affects the distribution of wildlife and represents a conservation concern, especially in Asia, which is experiencing rapid development. In Mongolia, mining, livestock grazing, infrastructure development and climate change represent major drivers of change that will impact habitats and few tools exist to predict how wildlife will respond. I examined the impacts of landscape change on the corsac fox (Vulpes corsac) in a steppe region of Mongolia. The corsac fox occurs widely throughout northern Asia, but has experienced declines in many regions and remains one the least studied canids. I addressed two questions: 1) how do common features of a landscape, such as habitats, topography, herder camps, and roads, shape the distribution of the species? and 2) how will changes in those features affect distribution in the future? I collected locations of foxes from radio-collared animals, scat surveys, and opportunistic sightings in Ikh Nart Nature Reserve, then used maximum likelihood methods and model selection techniques to develop a model that predicts occupancy probability. I then applied the model to simulations of landscape change. I collected 1,965 locations and examined 19 candidate models. The model with the most support indicated that occupancy is best described by the additive combination of shrublands, open plains, tall grasslands, and rocky habitat. Models with other covariates (camps, roads, and ruggedness) had little support. A Receiver-Operator-Characteristic plot of model performance had an Area Under the Curve of 77%, indicating that the model predicted occupancy better than expected by chance. Average occupancy across the reserve was 22% under current conditions. Incremental reductions in shrubland, open plains, and tall vegetation resulted in occupancy declines with average occupancy being 7%, 13%, and 14%, respectively, when these habitats were completely absent. The loss of all three habitats due to the desertification of the landscape through climate change resulted in an average occupancy of 7%. The results provide the first model of corsac fox occupancy, which can be used to quantitatively examine distribution and impacts of change in other parts of the species' range. In Ikh Nart, results suggest that climate change poses the greatest threat to the species as it is expected to reduce high quality habitats and confine corsac foxes to areas with high competition from red foxes.

Seit mehreren Jahrzehnten nehmen die Bestandszahlen von Bodenbrütern europaweit ab, ein Prozess, der hauptsächlich auf die Intensivierung der Landwirtschaft zurückzuführen ist. In diesem Zusammenhang könnte aber auch die zunehmende Prädation von Raubsäugern (Carnivora, Mammalia) eine wichtige Rolle spielen. Ziel dieser Studie war die Bewertung und Einschätzung des Prädationspotentials ausgewählter Raubsäugerarten auf Bodenbrüter im brandenburgischen Vogelschutzgebiet "Mittlere Havelniederung". Von Mai 2015 bis Juni 2017 wurde die Raumnutzung verschiedener Raubsäugerarten mittels Kamerafallen und einer Telemetriestudie untersucht und anschließend mit den Ergebnissen einer Vogelkartierung verglichen. Ergänzt wurden die Untersuchungen mit einer Losungsanalyse der am häufigsten beobachteten Raubsäugerarten Waschbär (Procyon lotor) und Rotfuchs (Vulpes vulpes). Waschbären wiesen eine hohe Standorttreue sowie eine hohe Präferenz für Gewässer und Feuchtgebiete auf, während Rotfüchse eine hohe intraspezifische Variabilität in Bezug auf ihre Habitatnutzung sowie ein hohes Abwanderungsverhalten zeigten. Die Ergebnisse lassen außerdem ein hohes Prädationspotential des Waschbären auf Wasservögel vermuten, während der Einfluss auf Wiesenbrüter geringer zu sein scheint. Diese scheinen den höchsten Prädationsdruck durch den Rotfuchs zu erfahren. Die Nahrungsanalysen bestätigen diese Ergebnisse und spiegeln auch räumliche Bewegungsmuster beider Arten wieder. Diese Studie liefert als eine der europaweit ersten Studien empirische Belege für ein starkes indirektes und direktes Prädationspotential des Waschbären insbesondere auf Wasservögel. Zudem hebt diese Studie die Notwendigkeit einer differenzierten Betrachtung potenzieller Auswirkungen von Raubsäugern auf Bodenbrüter hervor und gibt einen Hinweis darauf, dass das Prädationspotential einer Raubsäugerart eng mit der Strukturvielfalt eines Lebensraums und somit mit der Intensität der landwirtschaftlichen Bewirtschaftung zusammenhängt. / Over recent decades, a general decline in ground-nesting bird species has been recorded all over Europe and this trend is mainly a result of agricultural intensification. However, increasing predation pressure by carnivores (Carnivora, Mammalia) might also play an important role in this context. The aim of this study was to assess and evaluate the predatory potential of selected carnivore species on ground-nesting birds in the Special Protection Area `Mittlere Havelniederung’ in Brandenburg, Germany. Between May 2015 and June 2017, camera- trapping and a telemetry study were carried out to investigate the spatial behavior of mesocarnivore species. Subsequently, spatial data were compared with results of a bird mapping and complemented by an analysis of scat contents of the most abundant carnivore species raccoon (Procyon lotor) and red fox (Vulpes vulpes). Camera trapping revealed a high diversity of carnivores. In addition, spatial distribution patterns showed high site fidelity and an exclusive preference for waters and swamplands in raccoons, while red foxes showed a high level of intraspecific variance in habitat use and a pronounced level of migratory activity. Predator-prey spatial overlap assumes a high potential impact of raccoons on water-associated bird species, while their impact on grassland birds appears not as important. Grassland birds seem to experience highest predatory pressure by red foxes. Dietary analysis support these results and confirm species-specific spatial patterns. As one of the first studies in Europe, this study provides empirical evidence of raccoons’ strong indirect and direct predatory potential in particular on water-associated bird species. Besides, this study highlights the need for a differentiated view on the potential impact of carnivore species on ground-nesting birds and suggests, that the predatory potential of a carnivore species is linked with landscape diversity and thus with intensity of agricultural land use practices.