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Camacho Carlos - One of the best experts on this subject based on the ideXlab platform.
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Landscape change promotes the emergence of a rare predator-prey interaction
'Elsevier BV', 2020Co-Authors: Sáez-gómez Pedro, Palacios Sebastián, Camacho CarlosAbstract:Diet studies provide basic natural history information to understand food web dynamics. However, measuring the dietary breadth of rare, elusive species is extremely challenging due to their scarcity and/or cryptic behavior. We document, for the first time, an uncommon predatory interaction –nest predation– between two of the most elusive and rare species in Europe, the Iberian lynx (Lynx pardinus) and the red-necked Nightjar (Caprimulgus ruficollis). Data on individually tagged Nightjars and photo-traps were analysed together to investigate the underlying conditions that might have facilitated the fatal encounter. Human-induced changes in the landscape in 2014–2016 forced Nightjars to travel relatively large distances (1–2 km) from the nest to find food, which translated into considerably longer nest absences compared with previous years (2011−2012). This fact, together with a drastic decline in wild rabbit populations (the main prey of lynx), might lead lynxes to search for alternative food resources, such as unconcealed –and easily detectable– bird nests. Our results provide new data about the trophic ecology of this threatened predator and suggest that anthropogenic landscape changes may affect predator-prey relationships in unexpected ways.The Environmental Agency of Andalusia provided us with the license for Nightjar trapping, tagging and photo-trapping (permit numbers: 4358/1064/MDCG, 762/MDCG and 2016107300003028/IRM/MDCG). The authors have no conflict of interest to declare. This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. CC received finantial support from the Spanish Ministry of Economy and Competitiveness (SVP-2013-067686)
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Data on road use by red-necked Nightjars
DIGITAL.CSIC, 2019Co-Authors: Miguel De ,felipe, Sáez-gómez Pedro, Camacho CarlosAbstract:This data set includes 9 years (2009-2017) of data on the number of red-necked Nightjars (Caprimulgus ruficollis) encountered along a 24-km road network crossing a protected area of the Doñana Natural Park (Spain) 37°7′N, 6°33′ W. Nightjar counts were carried out on a weekly basis from the time of arrival from spring migration (early April) until autumn departure to their wintering quarters (late October). These counts began 1–2 h after sunset from fixed starting points by driving a vehicle at a constant speed of 30 km/h until the full 24-km route was completed. Meteorological information from the two nearest meteorological stations, located 17 km and 6 km from the study site, is also included in this data set.Peer reviewe
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Environmental factors influencing road use in a nocturnal insectivorous bird
'Springer Science and Business Media LLC', 2019Co-Authors: M. De ,felipe, Sáez-gómez Pedro, Camacho CarlosAbstract:Many animals avoid roads due to traffic disturbance, but there are also some species that use roads in their everyday life and even obtain resources from them. Understanding the factors that influence the intensity of road use by these species can help understand temporal patterns of road mortality and thereby maximise the cost-effectiveness of mitigation measures. Here, we use road transect counts conducted once a week for 9 consecutive years (2009–2017) to investigate environmental factors influencing road use in the red-necked Nightjar (Caprimulgus ruficollis), a nocturnal insectivorous bird that frequents roads to forage and thermoregulate. We found that the intensity of road use by Nightjars was affected by ambient temperature, amount of moonlight and wind conditions—all factors known to influence their foraging efficiency and thermoregulatory requirements. Specifically, the highest numbers of Nightjars on roads occurred during no-wind conditions and on either dark-cold or bright-warm nights, suggesting that they preferentially use roads for thermoregulation under unfavourable weather conditions or to maximise food intake during periods of increased insect abundance (i.e. warm nights) and improved conditions for visual prey detection (i.e. full moon). Our results illustrate the role of environmental conditions as drivers of rapid changes in the use of roads by animals. Furthermore, this work suggests that analogous studies can be used to inform mitigation measures, so that mitigation efforts to prevent roadkills can be concentrated during periods of expected peaks in animal use of roads.Peer Reviewe
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Environmental factors influencing road use in a nocturnal insectivorous bird
'Springer Science and Business Media LLC', 2019Co-Authors: De Felipe Miguel, Sáez-gómez Pedro, Camacho CarlosAbstract:Many animals avoid roads due to traffic disturbance, but there are also some species that use roads in their everyday life and even obtain resources from them. Understanding the factors that influence the intensity of road use by these species can help understand temporal patterns of road mortality and thereby maximise the cost-effectiveness of mitigation measures. Here, we use road transect counts conducted once a week for 9 consecutive years (2009–2017) to investigate environmental factors influencing road use in the red-necked Nightjar (Caprimulgus ruficollis), a nocturnal insectivorous bird that frequents roads to forage and thermoregulate. We found that the intensity of road use by Nightjars was affected by ambient temperature, amount of moonlight and wind conditions—all factors known to influence their foraging efficiency and thermoregulatory requirements. Specifically, the highest numbers of Nightjars on roads occurred during no-wind conditions and on either dark-cold or bright-warm nights, suggesting that they preferentially use roads for thermoregulation under unfavourable weather conditions or to maximise food intake during periods of increased insect abundance (i.e. warm nights) and improved conditions for visual prey detection (i.e. full moon). Our results illustrate the role of environmental conditions as drivers of rapid changes in the use of roads by animals. Furthermore, this work suggests that analogous studies can be used to inform mitigation measures, so that mitigation efforts to prevent roadkills can be concentrated during periods of expected peaks in animal use of roads.CC was supported by the Spanish Ministry of Economy and Competitiveness through the fellowship SVP–2013–067686
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Nightjars, rabbits, and foxes interact on unpaved roads: spatial use of a secondary prey in a shared-predator system
'Wiley', 2017Co-Authors: Camacho Carlos, Sáez Pedro, Potti Jaime, Fedriani, José M.Abstract:Linear developments, such as roads and firebreaks, can increase encounter rates between predator and prey, which could affect predator–prey interactions and community dynamics. However, the extent to which prey responses at the interface between natural and anthropogenic habitats may be compared to those at the interface between natural habitats is unclear. Here, we used a shared-predator system to investigate the spatial response of red-necked Nightjars (Caprimulgus ruficollis) to changing predation risk on roads, measured as the abundance of red foxes (Vulpes vulpes), and their primary prey (rabbits, Oryctolagus cuniculus). Because all three species coexist closely on unpaved roads in Do~nana National Park (Spain), we predicted that Nightjars would experience increased predation risk during periods of high fox and low rabbit abundances. Birds could then modify their space use at a broad scale by moving away from risky unpaved roads or, at a finer scale, by seeking foraging microsites facilitating escape from attacks. Between 2011 and 2012, mean rabbit abundance on roads increased by 50%, and fox abundance decreased by 80%, indicating a substantial decrease in predation risk for Nightjars. Unexpectedly, Nightjar occurrence on roads did not increase as a consequence of the decrease in fox predation risk. However, Nightjars foraging on roads became less apprehensive in their use of linear strips of roadside cover, which is known to function as a physical barrier against fox attacks. Specifically, under high predation risk, most Nightjars perched on the ground nearby (150 cm) vegetation, whereas when predation risk decreased, they shifted to more exposed microsites near shorter (45 cm). Nightjars’ preference for areas of high predator abundance strongly suggests that flexible microhabitat selection allows them to manage the overall predation risk independently of predator abundance. Our results highlight the importance of linear developments in determining risk exposure and prey use of apparently dangerous habitats and thus may contribute to a better understanding of risky behaviors of prey.Peer reviewe
Roel Evens - One of the best experts on this subject based on the ideXlab platform.
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dna diet profiles with high resolution animal tracking data reveal levels of prey selection relative to habitat choice in a crepuscular insectivorous bird
Ecology and Evolution, 2020Co-Authors: Natalie Beenaerts, Ian G Henderson, Greg J Conway, Roel Evens, Kirsty Franklin, Jennifer E Stockdale, Karen SmeetsAbstract:Given the global decline of many invertebrate food resources, it is fundamental to understand the dietary requirements of insectivores. We give new insights into the functional relationship between the spatial habitat use, food availability, and diet of a crepuscular aerial insectivore, the European Nightjar (Caprimulgus europaeus) by relating spatial use data with high-throughput sequencing (HTS) combined with DNA metabarcoding. Our study supports the predictions that Nightjars collect a substantial part of their daily nourishment from foraging locations, sometimes at considerable distance from nesting sites. Lepidopterans comprise 65% of Nightjars' food source. Nightjars tend to select larger species of Lepidoptera (>19 mm) which suggests that Nightjars optimize the efficiency of foraging trips by selecting the most energetically favorable-larger-prey items. We anticipate that our findings may shed additional light on the interactions between invertebrate communities and higher trophic levels, which is required to understand the repercussions of changing food resources on individual- and population-level processes.
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Proximity of breeding and foraging areas affects foraging effort of a crepuscular, insectivorous bird
Scientific Reports, 2018Co-Authors: Roel Evens, Natalie Beenaerts, Thomas Neyens, Karen Smeets, Nele Witters, Tom ArtoisAbstract:When complementary resources are required for an optimal life cycle, most animals need to move between different habitats. However, the level of connectivity between resources can vary and, hence, influence individuals’ behaviour. We show that landscape composition and configuration affect the connectivity between breeding (heathlands) and foraging habitats (extensively-grazed grasslands) of the European Nightjar (Caprimulgus europaeus), a crepuscular insectivorous bird. On a daily basis, Nightjars connect breeding and foraging sites by rapidly crossing unsuitable habitats in order to exploit a higher prey biomass in foraging sites. However, low availability of foraging habitat near breeding sites and clustered landscapes greatly increase foraging distance. Birds occupying these sub-optimal breeding areas compensate for longer travels by increasing foraging duration, and their physiology shows increased stress levels. All findings suggest that landscape heterogeneity can affect population dynamics of Nightjars. Therefore, we recommend an integrated management approach for this EU-protected bird species.
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Nightjar diversity and microhabitat use in nechisar national park ethiopia
Ostrich, 2017Co-Authors: Roel Evens, Natalie Beenaerts, Nele Witters, Tom ArtoisAbstract:Knowledge of the distribution and ecology of East African Nightjars is, to a large extent, unknown. We collected ecological information on the diversity and microhabitat use of Nightjars in Nechisar National Park in January 2015 by executing field captures and observations. We also attempted to find a live specimen of the Nechisar Nightjar Caprimulgus solala . During the course of 18 nights we observed five Nightjar species, captured 49 individuals and observed that Nightjars were closely associated with protective landscape elements. In spite of the intensity of our survey, we were not able to find a living specimen of the Nechisar Nightjar, which could indicate the species is either migratory or extinct.
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study on the foraging behaviour of the european Nightjar caprimulgus europaeus reveals the need for a change in conservation strategy in belgium
Journal of Avian Biology, 2017Co-Authors: Roel Evens, Natalie Beenaerts, Nele Witters, Tom ArtoisAbstract:Effective nature conservation requires coherent actions based on the best available evidence concerning protected species. Recent studies have suggested that European Nightjars Caprimulgus europaeus forage outside their recognized breeding habitats, yet, for Flanders (northern Belgium) information on Nightjar foraging behaviour and key foraging habitats is lacking. To assess whether the foraging ecology of Nightjars in Flanders is similar to that observed in other parts of Europe, we studied the crepuscular behaviour of this species in Bosland (northeastern Flanders) during a five-year radio telemetry study. Tracking of 48 individuals within a coniferous forest was standardized and home ranges were calculated using a kernel density estimator (fixed kernel). Habitat use was investigated by comparing kernel placement to available habitat. Average maximal foraging distance was 2603 ± 1094 m and home ranges extended up to 691 ha. We identified the key foraging habitats to be extensively-cultivated grasslands and recreational areas, areas that were previously assumed unsuitable for Belgian Nightjars. Our results indicate the importance of foraging sites outside the breeding territory, confirming the findings of previous studies performed elsewhere in Europe. Incorporating our findings into future conservation plans could, therefore, lead to improved efficiency of EU conservation measures, designed for the protection of this bird species in Flanders.
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repeated migration of a juvenile european Nightjar caprimulgus europaeus
Journal of Ornithology, 2017Co-Authors: Roel Evens, Natalie Beenaerts, Nele Witters, Tom ArtoisAbstract:Most of our current knowledge on migration strategies in juvenile light-weight birds originates from laboratory studies, displacement experiments and partial migration tracks. Here we report on the first recording of two consecutive migration cycles of one such light-weight migrant, the European Nightjar Caprimulgus europaeus. This bird visited the same stopover zones and wintering area in both years, but with earlier arrival times and less time spent at stopover zones in the second year. This unique dataset shows that adult Nightjars seem to possess the capability to perform some form of navigation towards areas which are established during the juvenile migration.
Tom Artois - One of the best experts on this subject based on the ideXlab platform.
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Proximity of breeding and foraging areas affects foraging effort of a crepuscular, insectivorous bird
Scientific Reports, 2018Co-Authors: Roel Evens, Natalie Beenaerts, Thomas Neyens, Karen Smeets, Nele Witters, Tom ArtoisAbstract:When complementary resources are required for an optimal life cycle, most animals need to move between different habitats. However, the level of connectivity between resources can vary and, hence, influence individuals’ behaviour. We show that landscape composition and configuration affect the connectivity between breeding (heathlands) and foraging habitats (extensively-grazed grasslands) of the European Nightjar (Caprimulgus europaeus), a crepuscular insectivorous bird. On a daily basis, Nightjars connect breeding and foraging sites by rapidly crossing unsuitable habitats in order to exploit a higher prey biomass in foraging sites. However, low availability of foraging habitat near breeding sites and clustered landscapes greatly increase foraging distance. Birds occupying these sub-optimal breeding areas compensate for longer travels by increasing foraging duration, and their physiology shows increased stress levels. All findings suggest that landscape heterogeneity can affect population dynamics of Nightjars. Therefore, we recommend an integrated management approach for this EU-protected bird species.
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Nightjar diversity and microhabitat use in nechisar national park ethiopia
Ostrich, 2017Co-Authors: Roel Evens, Natalie Beenaerts, Nele Witters, Tom ArtoisAbstract:Knowledge of the distribution and ecology of East African Nightjars is, to a large extent, unknown. We collected ecological information on the diversity and microhabitat use of Nightjars in Nechisar National Park in January 2015 by executing field captures and observations. We also attempted to find a live specimen of the Nechisar Nightjar Caprimulgus solala . During the course of 18 nights we observed five Nightjar species, captured 49 individuals and observed that Nightjars were closely associated with protective landscape elements. In spite of the intensity of our survey, we were not able to find a living specimen of the Nechisar Nightjar, which could indicate the species is either migratory or extinct.
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study on the foraging behaviour of the european Nightjar caprimulgus europaeus reveals the need for a change in conservation strategy in belgium
Journal of Avian Biology, 2017Co-Authors: Roel Evens, Natalie Beenaerts, Nele Witters, Tom ArtoisAbstract:Effective nature conservation requires coherent actions based on the best available evidence concerning protected species. Recent studies have suggested that European Nightjars Caprimulgus europaeus forage outside their recognized breeding habitats, yet, for Flanders (northern Belgium) information on Nightjar foraging behaviour and key foraging habitats is lacking. To assess whether the foraging ecology of Nightjars in Flanders is similar to that observed in other parts of Europe, we studied the crepuscular behaviour of this species in Bosland (northeastern Flanders) during a five-year radio telemetry study. Tracking of 48 individuals within a coniferous forest was standardized and home ranges were calculated using a kernel density estimator (fixed kernel). Habitat use was investigated by comparing kernel placement to available habitat. Average maximal foraging distance was 2603 ± 1094 m and home ranges extended up to 691 ha. We identified the key foraging habitats to be extensively-cultivated grasslands and recreational areas, areas that were previously assumed unsuitable for Belgian Nightjars. Our results indicate the importance of foraging sites outside the breeding territory, confirming the findings of previous studies performed elsewhere in Europe. Incorporating our findings into future conservation plans could, therefore, lead to improved efficiency of EU conservation measures, designed for the protection of this bird species in Flanders.
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repeated migration of a juvenile european Nightjar caprimulgus europaeus
Journal of Ornithology, 2017Co-Authors: Roel Evens, Natalie Beenaerts, Nele Witters, Tom ArtoisAbstract:Most of our current knowledge on migration strategies in juvenile light-weight birds originates from laboratory studies, displacement experiments and partial migration tracks. Here we report on the first recording of two consecutive migration cycles of one such light-weight migrant, the European Nightjar Caprimulgus europaeus. This bird visited the same stopover zones and wintering area in both years, but with earlier arrival times and less time spent at stopover zones in the second year. This unique dataset shows that adult Nightjars seem to possess the capability to perform some form of navigation towards areas which are established during the juvenile migration.
Natalie Beenaerts - One of the best experts on this subject based on the ideXlab platform.
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dna diet profiles with high resolution animal tracking data reveal levels of prey selection relative to habitat choice in a crepuscular insectivorous bird
Ecology and Evolution, 2020Co-Authors: Natalie Beenaerts, Ian G Henderson, Greg J Conway, Roel Evens, Kirsty Franklin, Jennifer E Stockdale, Karen SmeetsAbstract:Given the global decline of many invertebrate food resources, it is fundamental to understand the dietary requirements of insectivores. We give new insights into the functional relationship between the spatial habitat use, food availability, and diet of a crepuscular aerial insectivore, the European Nightjar (Caprimulgus europaeus) by relating spatial use data with high-throughput sequencing (HTS) combined with DNA metabarcoding. Our study supports the predictions that Nightjars collect a substantial part of their daily nourishment from foraging locations, sometimes at considerable distance from nesting sites. Lepidopterans comprise 65% of Nightjars' food source. Nightjars tend to select larger species of Lepidoptera (>19 mm) which suggests that Nightjars optimize the efficiency of foraging trips by selecting the most energetically favorable-larger-prey items. We anticipate that our findings may shed additional light on the interactions between invertebrate communities and higher trophic levels, which is required to understand the repercussions of changing food resources on individual- and population-level processes.
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Proximity of breeding and foraging areas affects foraging effort of a crepuscular, insectivorous bird
Scientific Reports, 2018Co-Authors: Roel Evens, Natalie Beenaerts, Thomas Neyens, Karen Smeets, Nele Witters, Tom ArtoisAbstract:When complementary resources are required for an optimal life cycle, most animals need to move between different habitats. However, the level of connectivity between resources can vary and, hence, influence individuals’ behaviour. We show that landscape composition and configuration affect the connectivity between breeding (heathlands) and foraging habitats (extensively-grazed grasslands) of the European Nightjar (Caprimulgus europaeus), a crepuscular insectivorous bird. On a daily basis, Nightjars connect breeding and foraging sites by rapidly crossing unsuitable habitats in order to exploit a higher prey biomass in foraging sites. However, low availability of foraging habitat near breeding sites and clustered landscapes greatly increase foraging distance. Birds occupying these sub-optimal breeding areas compensate for longer travels by increasing foraging duration, and their physiology shows increased stress levels. All findings suggest that landscape heterogeneity can affect population dynamics of Nightjars. Therefore, we recommend an integrated management approach for this EU-protected bird species.
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Nightjar diversity and microhabitat use in nechisar national park ethiopia
Ostrich, 2017Co-Authors: Roel Evens, Natalie Beenaerts, Nele Witters, Tom ArtoisAbstract:Knowledge of the distribution and ecology of East African Nightjars is, to a large extent, unknown. We collected ecological information on the diversity and microhabitat use of Nightjars in Nechisar National Park in January 2015 by executing field captures and observations. We also attempted to find a live specimen of the Nechisar Nightjar Caprimulgus solala . During the course of 18 nights we observed five Nightjar species, captured 49 individuals and observed that Nightjars were closely associated with protective landscape elements. In spite of the intensity of our survey, we were not able to find a living specimen of the Nechisar Nightjar, which could indicate the species is either migratory or extinct.
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study on the foraging behaviour of the european Nightjar caprimulgus europaeus reveals the need for a change in conservation strategy in belgium
Journal of Avian Biology, 2017Co-Authors: Roel Evens, Natalie Beenaerts, Nele Witters, Tom ArtoisAbstract:Effective nature conservation requires coherent actions based on the best available evidence concerning protected species. Recent studies have suggested that European Nightjars Caprimulgus europaeus forage outside their recognized breeding habitats, yet, for Flanders (northern Belgium) information on Nightjar foraging behaviour and key foraging habitats is lacking. To assess whether the foraging ecology of Nightjars in Flanders is similar to that observed in other parts of Europe, we studied the crepuscular behaviour of this species in Bosland (northeastern Flanders) during a five-year radio telemetry study. Tracking of 48 individuals within a coniferous forest was standardized and home ranges were calculated using a kernel density estimator (fixed kernel). Habitat use was investigated by comparing kernel placement to available habitat. Average maximal foraging distance was 2603 ± 1094 m and home ranges extended up to 691 ha. We identified the key foraging habitats to be extensively-cultivated grasslands and recreational areas, areas that were previously assumed unsuitable for Belgian Nightjars. Our results indicate the importance of foraging sites outside the breeding territory, confirming the findings of previous studies performed elsewhere in Europe. Incorporating our findings into future conservation plans could, therefore, lead to improved efficiency of EU conservation measures, designed for the protection of this bird species in Flanders.
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repeated migration of a juvenile european Nightjar caprimulgus europaeus
Journal of Ornithology, 2017Co-Authors: Roel Evens, Natalie Beenaerts, Nele Witters, Tom ArtoisAbstract:Most of our current knowledge on migration strategies in juvenile light-weight birds originates from laboratory studies, displacement experiments and partial migration tracks. Here we report on the first recording of two consecutive migration cycles of one such light-weight migrant, the European Nightjar Caprimulgus europaeus. This bird visited the same stopover zones and wintering area in both years, but with earlier arrival times and less time spent at stopover zones in the second year. This unique dataset shows that adult Nightjars seem to possess the capability to perform some form of navigation towards areas which are established during the juvenile migration.
R T Clarke - One of the best experts on this subject based on the ideXlab platform.
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what effects do walkers and dogs have on the distribution and productivity of breeding european Nightjar caprimulgus europaeus
Ibis, 2007Co-Authors: Rowena H. W. Langston, D Liley, G Murison, Emma Woodfield, R T ClarkeAbstract:Several successive studies of European Nightjars Caprimulgus europaeus (hereafter, Nightjar) on the Dorset heaths demonstrated negative effects of the proximity of urban development and associated disturbance from access on foot by people and dogs. Surrogate measures of human density and settlement, including the amount of developed land around each heathland patch and the number of houses, were significantly and negatively related to the density of Nightjars (using data from the 1992 national survey) on heathland patches, regardless of patch size. These findings prompted targeted field studies, the subject of this paper, which investigated the mechanisms and effects of recreational disturbance on breeding Nightjars. Fieldwork in 2002 focused on a suite of heathland sites representing a range of access from sites closed to the public to heaths heavily used for recreation, notably by dog walkers. Studies in 2003 concentrated on the heavily used heaths. Nests which failed were significantly closer to paths, tended to be closer to the main points of access to heaths, in areas with higher footpath density, notably of high levels of use, and in more sparsely vegetated locations. The proximate cause of nest failure was most frequently egg predation. Nest cameras, deployed in 2003 in an attempt to identify the predators of eggs or chicks, recorded just one instance of predation, that of an egg by a Carrion Crow Corvus corone , and two instances of the incubating bird being flushed by a dog, once from an egg and once from a chick, neither event preventing fledging. Flushing rate of Nightjars from the nest was associated with the height of vegetation around the nest and the extent of nest cover. The studies indicate that access disturbance interacts with environmental conditions for breeding birds. Birds flush more readily from eggs, which are highly visible when exposed, especially in areas with sparse nest cover, leaving them vulnerable to predation. Although Nightjar flushing rates were observed to be low in 2003, just one event leading to predation is enough to end that nesting attempt. Management measures are recommended to minimize the effects of walkers and their dogs on Nightjars.
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the impact of urban development and human disturbance on the numbers of Nightjar caprimulgus europaeus on heathlands in dorset england
Biological Conservation, 2003Co-Authors: D Liley, R T ClarkeAbstract:Abstract The factors influencing the number of Nightjars on 36 heathland sites (referred to as patches) in Dorset, England were examined using novel spatial integration of existing datasets. Surrogate measures of human density and settlement, including the amount of developed land at different distances from the heath (obtained from aerial photographs) and the actual number of buildings (obtained from Post Code databases) were all found to be highly correlated with each other and to show a strong negative relationship with the density of Nightjars present on a patch, regardless of patch size. The amount of woodland (the preferred foraging habitat) surrounding each patch (within 500 m of the patch boundary) was also a significant predictor of Nightjar numbers. When used together, the extent of woodland and developed land both gave significant improvements to predictions of Nightjar density. The results indicate that the number of Nightjars present on a heathland patch is influenced by the surrounding land-use and that the effect of urban development is more than just habitat loss. We suggest that trends identified are at least partly due to actual human presence on the heathlands and as such, human disturbance is potentially a problem for this species.