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Medical examiner (Philadelphia, Pa.)
2023 Band 2, Heft 17, Seite(n) 289
| Sprache | Englisch |
|---|---|
| Erscheinungsdatum | 2023-12-20 |
| Erscheinungsland | United States |
| Dokumenttyp | Journal Article |
| Datenquelle | MEDical Literature Analysis and Retrieval System OnLINE |
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Ecology and evolution, 6(4): 974-986
2016
Abstract: Reducing resource competition is a crucial requirement for colonial seabirds to ensure adequate self‐ and chick‐provisioning during breeding season. Spatial segregation is a common avoidance strategy among and within species from neighboring breeding ... ...
| Körperschaft | Leibniz-Institut für Zoo- und Wildtierforschung (Berlin) |
|---|---|
| Abstract | Reducing resource competition is a crucial requirement for colonial seabirds to ensure adequate self‐ and chick‐provisioning during breeding season. Spatial segregation is a common avoidance strategy among and within species from neighboring breeding colonies. We determined whether the foraging behaviors of incubating lesser black‐backed gulls (Larus fuscus) differed between six colonies varying in size and distance to mainland, and whether any differences could be related to the foraging habitats visited. Seventy‐nine incubating individuals from six study colonies along the German North Sea coast were equipped with GPS data loggers in multiple years. Dietary information was gained by sampling food pellets, and blood samples were taken for stable isotope analyses. Foraging patterns clearly differed among and within colonies. Foraging range increased with increasing colony size and decreased with increasing colony distance from the mainland, although the latter might be due to the inclusion of the only offshore colony. Gulls from larger colonies with consequently greater density‐dependent competition were more likely to forage at land instead of at sea. The diets of the gulls from the colonies furthest from each other differed, while the diets from the other colonies overlapped with each other. The spatial segregation and dietary similarities suggest that lesser black‐backed gulls foraged at different sites and utilized two main habitat types, although these were similar across foraging areas for all colonies except the single offshore island. The avoidance of intraspecific competition results in colony‐specific foraging patterns, potentially causing more intensive utilization of terrestrial foraging sites, which may offer more predictable and easily available foraging compared with the marine environment. |
| Schlagwörter | GPS tracking ; Foraging strategy ; Larus fuscus ; intraspecific competition ; stable isotope analyses ; utilization distribution |
| Sprache | Englisch |
| Dokumenttyp | Artikel |
| Datenquelle | Fachrepositorium Lebenswissenschaften |
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Journal of applied ecology, 54: 1110-1119
2016
Abstract: 1. Competition among sympatric wild herbivores is reduced by different physiological, morphological and behavioural traits resulting in different dietary niches. Wild equids are a rather uniform group of large herbivores which have dramatically declined ... ...
| Körperschaft | Leibniz-Institut für Zoo- und Wildtierforschung (Berlin) |
|---|---|
| Abstract | 1. Competition among sympatric wild herbivores is reduced by different physiological, morphological and behavioural traits resulting in different dietary niches. Wild equids are a rather uniform group of large herbivores which have dramatically declined in numbers and range. Correlative evidence suggests that pasture competition with livestock is one of the key factors for this decline, and the situation may be aggravated in areas where different equid species overlap. 2. The Dzungarian Gobi is currently the only place where two wild equid species coexist and share the range with the domesticated form of a third equid species. In the winter‐cold Gobi desert pasture productivity is low, highly seasonal, and wild equids additionally face increasing livestock densities. 3. We used stable isotope chronologies of tail hairs to draw inferences about multi‐year diet seasonality, isotopic dietary niches and physiological adaptations in the Asiatic wild ass (khulan), re‐introduced Przewalski's horse, and domestic horse in the Mongolian part of the Dzungarian Gobi. 4. Our results showed that even in the arid Gobi, both horse species are predominantly grazers, whereas khulan are highly seasonal, switching from being grazers in summer to mixed feeders in winter. The isotopic dietary niches of the two horse species were almost identical, did not vary with season as in khulan and were narrower than in the latter. Higher δ15N values point towards higher water use efficiency in khulan, which may be one reason why they can exploit pastures further away from water. 5. Synthesis and applications. The high degree of isotopic dietary niche overlap in the two horse species in the Mongolian Gobi points towards a high potential for pasture competition during the critical nutritional bottleneck in winter and highlights the need to severely restrict grazing of domestic horses on the range of the Przewalski's horses. The evolutionary more distant khulan are less constrained by water and seem more flexible in their choice of diet or less successful in exploiting grass‐dominated habitats in winter due to human presence. Providing additional water sources could increase the competition between khulan and livestock and should, therefore, only be done following careful consideration. |
| Schlagwörter | Asiatic wild ass ; Dzungarian Gobi ; Equus ferus przewalskii ; Equus hemionus ; Przewalski’s horse ; feeding ecology ; isotope analysis ; isotopic dietary niche ; pasture competition |
| Sprache | Englisch |
| Dokumenttyp | Artikel |
| Datenquelle | Fachrepositorium Lebenswissenschaften |
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Movement Ecology, 4:16
2016
Abstract: BACKGROUND: Knowledge of immigration and emigration rates is crucial for understanding of population dynamics, yet little is known about these vital rates, especially for arctic songbirds. We estimated immigration in an Arctic population of northern ... ...
| Körperschaft | Leibniz-Institut für Zoo- und Wildtierforschung (Berlin) |
|---|---|
| Abstract | BACKGROUND: Knowledge of immigration and emigration rates is crucial for understanding of population dynamics, yet little is known about these vital rates, especially for arctic songbirds. We estimated immigration in an Arctic population of northern wheatears on Baffin Island, Canada, by the use of stable hydrogen isotopes in tail feathers (δ2HK). We assumed that δ2HK values of juvenile (hatch-year) feathers grown at the breeding grounds were representative of the local population, while those of breeding adults were indicative of where they grew their feathers during their post-breeding molt the previous year. The extent to which adult isotope values differ from those of juveniles provides an estimate of the minimum level of immigration into the breeding population. RESULTS: Mean δ2HK values did not differ in juvenile birds between years. Breeding adult birds did not differ significantly in mean δ2HK values compared to juveniles but did differ in their respective standard deviations, reflecting a significantly wider range of isotopic signatures in adults than in juveniles. Thirty-eight percent of the δ2HK values in adults were greater ± 2 SD of the mean δ2HK values of juveniles, suggesting that at least 38 % of the breeding adults were of non-local origin, thus immigrants from elsewhere. CONCLUSIONS: Although the use of stable isotopes has limitations, the use of stable-hydrogen isotopic markers has the potential to contribute valuable information towards understanding immigration rates in bird populations. In our study, hydrogen isotope measurements of the feathers of northern wheatears indicated a high rate of immigration into the breeding population, which is consistent with low return rates of banded breeding adults as well as implying high emigration rates of local breeders. |
| Schlagwörter | Dispersal ; Immigration ; Oenanthe oenanthe ; Northern wheatear ; Stable isotopes |
| Sprache | Englisch |
| Dokumenttyp | Artikel |
| Datenquelle | Fachrepositorium Lebenswissenschaften |
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PLOS ONE, 11(6):e0157394
2016
Abstract: Individuals within populations often differ substantially in habitat use, the ecological consequences of which can be far reaching. Stable isotope analysis provides a convenient and often cost effective means of indirectly assessing the habitat use of ... ...
| Körperschaft | Leibniz-Institut für Zoo- und Wildtierforschung (Berlin) |
|---|---|
| Abstract | Individuals within populations often differ substantially in habitat use, the ecological consequences of which can be far reaching. Stable isotope analysis provides a convenient and often cost effective means of indirectly assessing the habitat use of individuals that can yield valuable insights into the spatiotemporal distribution of foraging specialisations within a population. Here we use the stable isotope ratios of southern sea lion (Otaria flavescens) pup vibrissae at the Falkland Islands, in the South Atlantic, as a proxy for adult female habitat use during gestation. A previous study found that adult females from one breeding colony (Big Shag Island) foraged in two discrete habitats, inshore (coastal) or offshore (outer Patagonian Shelf). However, as this species breeds at over 70 sites around the Falkland Islands, it is unclear if this pattern is representative of the Falkland Islands as a whole. In order to characterize habitat use, we therefore assayed carbon (δ13C) and nitrogen (δ15N) ratios from 65 southern sea lion pup vibrissae, sampled across 19 breeding colonies at the Falkland Islands. Model-based clustering of pup isotope ratios identified three distinct clusters, representing adult females that foraged inshore, offshore, and a cluster best described as intermediate. A significant difference was found in the use of inshore and offshore habitats between West and East Falkland and between the two colonies with the largest sample sizes, both of which are located in East Falkland. However, habitat use was unrelated to the proximity of breeding colonies to the Patagonian Shelf, a region associated with enhanced biological productivity. Our study thus points towards other factors, such as local oceanography and its influence on resource distribution, playing a prominent role in inshore and offshore habitat use. |
| Schlagwörter | Animal sexual behaviour ; Animal sociality ; Foraging ; Habitats ; Islands ; Sea lions ; Stable isotopes ; Vibrissae |
| Sprache | Englisch |
| Dokumenttyp | Artikel |
| Datenquelle | Fachrepositorium Lebenswissenschaften |
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der Zugang zum Gesundheitssystem für Unionsbürger und ihre Familienangehörigen
2014
| Verfasserangabe | [Autor: Claudius Voigt. Red.: Jenny Bonin]. Deutscher Paritätischer Wohlfahrstverband Gesamtverband e.V |
|---|---|
| Sprache | Deutsch |
| Umfang | 36 S. : Ill. |
| Ausgabenhinweis | 1. Aufl. |
| Verlag | Der Paritätische Gesamtverb |
| Erscheinungsort | Berlin |
| Erscheinungsland | Deutschland |
| Dokumenttyp | Buch ; Online |
| HBZ-ID | HT018732933 |
| Datenquelle | ZB MED Katalog Medizin, Gesundheit, Ernährung, Umwelt, Agrar |
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der Zugang zum Gesundheitssystem für Unionsbürger und ihre Familienangehörigen
2014
| Verfasserangabe | [Autor: Claudius Voigt. Red.: Jenny Bonin]. Deutscher Paritätischer Wohlfahrstverband Gesamtverband e.V |
|---|---|
| Sprache | Deutsch |
| Umfang | 36 S. : Ill., 30 cm |
| Ausgabenhinweis | 1. Aufl. |
| Verlag | Der Paritätische Gesamtverb |
| Erscheinungsort | Berlin |
| Erscheinungsland | Deutschland |
| Dokumenttyp | Buch |
| HBZ-ID | HT018738278 |
| Datenquelle | Katalog ZB MED Medizin, Gesundheit |
| Signatur | Leihstatus | Standort |
|---|---|---|
| 2015 A 3121 | ausleihbar (Lesesaal) | Lesesaal EG |
Dieser Service ist kostenpflichtig (siehe Lieferbedingungen von subito). Bestellungen, die einen Artikel nebst Supplementary Material umfassen, werden grundsätzlich wie mehrfache Bestellungen bearbeitet. Gebühren fallen in diesen Fällen für jede einzelne Bestellung an.
2014
| Verfasserangabe | vorgelegt von Christian Voigt |
|---|---|
| Sprache | Deutsch |
| Umfang | VIII, 85 Bl., Bl. IX - XXIX : graph. Darst. |
| Erscheinungsland | Deutschland |
| Dokumenttyp | Buch ; Dissertation / Habilitation |
| Dissertation / Habilitation | Magdeburg, Univ., Diss., 2013 |
| HBZ-ID | HT018292164 |
| Datenquelle | Katalog ZB MED Medizin, Gesundheit |
| Signatur | Leihstatus | Standort |
|---|---|---|
| 2014 E 776 | bestellbar zur Ausleihe | Magazin |
Dieser Service ist kostenpflichtig (siehe Lieferbedingungen von subito). Bestellungen, die einen Artikel nebst Supplementary Material umfassen, werden grundsätzlich wie mehrfache Bestellungen bearbeitet. Gebühren fallen in diesen Fällen für jede einzelne Bestellung an.
Global ecology and conservation, 21:e00808
2019
Abstract: Artificial light at night has large impacts on nocturnal wildlife such as bats, yet its effect varies with wavelength of light, context, and across species involved. Here, we studied in two experiments how wild bats of cave-roosting species (Rhinolophus ... ...
| Körperschaft | Leibniz-Institut für Zoo- und Wildtierforschung (Berlin) |
|---|---|
| Abstract | Artificial light at night has large impacts on nocturnal wildlife such as bats, yet its effect varies with wavelength of light, context, and across species involved. Here, we studied in two experiments how wild bats of cave-roosting species (Rhinolophus mehelyi, R. euryale, Myotis capaccinii and Miniopterus schreibersii) respond to LED lights of different colours. In dual choice experiments, we measured the acoustic activity of bats in response to neutral-white, red or amber LED at a cave entrance and in a flight room – mimicking a cave interior. In the flight room, M. capaccinii and M. schreibersii preferred red to white light, but showed no preference for red over amber, or amber over white light. In the cave entrance experiment, all light colours reduced the activity of all emerging species, yet red LED had the least negative effect. Rhinolophus species reacted most strongly, matching their refusal to fly at all under any light treatment in the flight room. We conclude that the placement and light colour of LED light should be considered carefully in lighting concepts for caves both in the interior and at the entrance. In a cave interior, red LED light could be chosen – if needed at all – for careful temporary illumination of areas, yet areas important for bats should be avoided based on the precautionary principle. At cave entrances, the high sensitivity of most bat species, particularly of Rhinolophus spp., towards light sources almost irrespective of colour, calls for utmost caution when illuminating cave entrances. |
| Schlagwörter | Chiroptera ; ALAN ; LED ; Light colour ; Roost ; Urbanisation |
| Sprache | Englisch |
| Dokumenttyp | Artikel |
| Datenquelle | Fachrepositorium Lebenswissenschaften |
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Frontiers in Ecology and Evolution, 7:91
2019
Abstract: With urban areas growing worldwide, so does artificial light at night (ALAN) which negatively affects many nocturnal animals, including bats. The response of bats to ALAN ranges from some opportunistic species taking advantage of insect aggregations ... ...
| Körperschaft | Leibniz-Institut für Zoo- und Wildtierforschung (Berlin) |
|---|---|
| Abstract | With urban areas growing worldwide, so does artificial light at night (ALAN) which negatively affects many nocturnal animals, including bats. The response of bats to ALAN ranges from some opportunistic species taking advantage of insect aggregations around street lamps, particularly those emitting ultraviolet (UV) light, to others avoiding lit areas at all. Tree cover has been suggested to mitigate the negative effects of ALAN on bats by shielding areas against light scatter. Here, we investigated the effect of tree cover on the relationship between ALAN and bats in Berlin, Germany. In particular, we asked if this interaction varies with the UV light spectrum of street lamps and also across urban bat species. We expected trees next to street lamps to block ALAN, making the adjacent habitat more suitable for all species, irrespective of the wavelength spectrum of the light source. Additionally, we expected UV emitting lights next to trees to attract insects and thus, opportunistic bats. In summer 2017, we recorded bat activity at 22 green open spaces in Berlin using automated ultrasonic detectors. We analyzed bat activity patterns and landscape variables (number of street lamps with and without UV light emission, an estimate of light pollution, and tree cover density around each recording site within different spatial scales) using generalized linear mixed-effects models with a negative binomial distribution. We found a species-specific response of bats to street lamps with and without UV light, providing a more detailed picture of ALAN impacts than simply total light radiance. Moreover, we found that dense tree cover dampened the negative effect of street lamps without UV for open-space foraging bats of the genera Nyctalus, Eptesicus, and Vespertilio, yet it amplified the already existing negative or positive effect of street lamps with or without UV on Pipistrellus pipistrellus, P. pygmaeus, and Myotis spp. Our study underpins the importance of minimizing artificial light at night close to vegetation, particularly for bats adapted to spatial complexity in the environment (i.e., clutter-adapted species), and to increase dense vegetation in urban landscape to provide, besides roosting opportunities, protection against ALAN for open-space foraging bats in city landscapes. |
| Schlagwörter | ALAN ; canopy cover ; chiroptera ; bats ; light-emitting diodes ; trees ; ultraviolet light ; urban |
| Sprache | Englisch |
| Dokumenttyp | Artikel |
| Datenquelle | Fachrepositorium Lebenswissenschaften |
Sie können sich den gewünschten Titel als lokale Nutzerin oder lokaler Nutzer von ZB MED direkt an den Standort Köln schicken lassen.