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1.
Residues of chlorinated hydrocarbon insectidies and some of their metabolites, including p,p'-DDT, p,p'-DDD, p,p'-DDE, gamma-BHC, aldrin, dieldrin, heptachlor and heptachlor epoxide, were examined in the soils collected from 21 tea-gardens distributed in 15 countries of 6 prefectures in 1977, and from 100 locations distributed in 46 counties of 10 prefectures in 1984 in Taiwan. Although the use of these chlorinated hydrocarbon insecticides has been banned for many years, minor amounts of residues in the soils have still been detected. From 1977 to 1984, average residues of the chlorinated hydrocarbon insecticides and their metabolites in the soils of tea-gardens decreased from 5.64 to 0.06 ppb for gamma-BHC, 97 54 to 1.10 ppb for aldrin, 35.91 to 1.00 ppb for p,p'-DDE, 17.41 to 0.28 ppb for dieldrin, and 30.17 to 3.42 ppb for p,p'-DDT. But the number of positive cases increased for all chlorinated hydrocarbon insecticides tested, the residual levels were not significantly different among soils with different physiochemical properties or among soil layers. No significant amount of these insecticides was found in the processed tea.  相似文献   

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A comparison of digestive efficiency in birds of prey   总被引:3,自引:0,他引:3  
Differences in how raptors hunt and what they catch are correlated with size-independent differences in length of the small intestine, the region of the digestive tract responsible for food absorption. The study examined the functional significance of these differences among ten raptor species. Dry matter apparent digestive efficiency was calculated for each species fed a diet of day-old cockerels. For Falconiformes and Strigiformes, efficiencies varied between 75% and 82%, digestive efficiency being positively correlated with intestine length.
Generalist species, with a wide prey spectrum and feeding on relatively easily caught prey and carrion, had long intestines and high digestive efficiencies. Raptors specializing on fast-moving, avian prey had short intestines and reduced digestive efficiency. The Peregrine Falco peregrinus and the Common Buzzard Buteo buteo were used as examples of specialist and generalist feeders, respectively. Rabbit and pigeon were fed to both. Buzzards digested both diets more efficiently than Peregrines. Body-mass changes were used to examine the nutritional value of the two diets to each species. Buzzards gained body-mass when eating rabbit, Peregrines lost mass. Both species gained mass when feeding on pigeon. It seems that consideration of diet quality, not just quantity, is essential in understanding raptor food requirements. Generalist raptors have high efficiencies on several diets, specialists compensate for their reduced efficiency by eating food of high nutritional quality. Various aspects of prey quality are examined.  相似文献   

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Post-mortem findings in East African birds of prey   总被引:1,自引:0,他引:1  
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Chlorinated hydrocarbon insecticides quench the fluorescence of N-alkyl derivatives of carbazole. We used phospholipids with covalently attached carbazole as probes for the interactions of chlorinated hydrocarbon insecticides with lipid bilayers, the object being to understand better the toxicities of chlorinated hydrocarbons. Fluorescence quenching measurements revealed the lipid-water partition coefficients of the chlorinated hydrocarbons, their diffusion coefficients in the membranes, and the binding capacities of the membranes for the chlorinated hydrocarbons. Active insecticides were compared with inactive analogues to test whether activities correlated with chlorinated hydrocarbon-membrane interactions. Thus DDT and methoxychlor were compared with inactive DDE, and insecticidal γ-lindane was compared with three less active stereoisomers. The partition coefficients, diffusion coefficients and membrane saturation capacities did not correlate with insecticidal potency. The partition coefficients of these chlorinated hydrocarbons were larger in bilayers containing unsaturated fatty acyl chains as compared to bilayers containing saturated fatty acyl chains. Interestingly, neural membranes are known to contain a large percentage of unsaturated lipids. Our results indicate that the activities of chlorinated hydrocarbons are not a result of specific interactions of these compounds with the lipids of membranes. However, the neurotoxicity of chlorinated hydrocarbons may be amplified by selective partitioning in the unsaturated neural membranes.  相似文献   

6.
Packed cell volume, haemoglobin and erythrocyte counts are given for 52 East African birds of prey of 21 species. Whilst the majority of the birds sampled were "normal", some were injured or diseased. The results are discussed and attention is drawn to the possible value of haematology in clinical diagnosis.  相似文献   

7.
A wide-range survey of cross-species microsatellite amplification in birds   总被引:23,自引:1,他引:22  
The possibility to perform cross-species microsatellite amplification in birds was surveyed by analysing sets of primers developed from the swallow and the pied flycatcher genomes on a panel of 48 different bird species. In total, 162 cases (species/marker combinations) of heterologous amplification were recorded. Ten amplification products were sequenced and all were found to be true homologues of the original loci. There was a significant and negative relationship between microsatellite performance and evolutionary distance between the original species and the tested species. As a rough indicator of expected cross-species microsatellite performance we estimate that 50% of markers will reveal polymorphism in a species with a DNA-DNA hybridization δTmH value of 5 separating it from the original species. This corresponds to a divergence time of = 11 million years before present for passerine birds. The established relationship between performance and evolutionary distance agrees very well with data obtained from some mammalian species. The proportion of polymorphic loci among those markers that amplified decreased with increasing genetic distance, suggesting that few long repeats are preserved during evolution. One of the swallow markers, HrU2, amplified a specific product in all species analysed and will thus allow access to nuclear sequence data over a broad range of species. The only predictor of cross-species performance was the amount of non-specific amplification seen in the original species. An analysis of 10 species from within the family Hirundinidae with the swallow primers consistently revealed extensive polymorphism with average probabilities of identical genotypes ranging from 6 times 10-4 to 6 times 10-7. There were distinct allele frequency differences between the Hirundinidae species and we envisage that microsatellite cross-species amplification will be a useful tool in phylogeny construction and in species identification.  相似文献   

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Mycoplasmas are well-known avian pathogens of poultry and some passerines. Although reported in birds of prey, their role as pathogens is still unclear. Healthy, free-ranging raptor nestlings sampled during a routine ringing (banding) program, and birds of prey from rehabilitation centers, tested positive for Mycoplasma spp. by culture and a genus-specific polymerase chain reaction (PCR). Given the lack of clinical signs and disease, we suggest that mycoplasmas in raptors may be commensal rather than pathogenic. Using immunobinding assay and species-specific PCR tests, Mycoplasma buteonis, M. falconis, and M. gypis were identified; M. falconis was only detected in falcons. Additionally, some isolates could not be identified. This is the first report of Mycoplasma spp. isolations from Western Marsh Harriers (Circus aeroginosus), a Eurasian Hobby (Falco subbuteo), and a Barn Owl (Tyto alba).  相似文献   

11.
In field-scale mass balance studies of poplar remediation of carbon tetrachloride (CT), more than 95% of the mass of CT was degraded with all of the CT chlorine accountable as chloride ion accumulation in the soil. Atmospheric loss of CT through leaf transpiration and trunk diffusion was insignificant. These findings are consistent with previously reported uptake and degradation of trichloroethylene (TCE) by poplar. Poplar phytoremediation of CT and TCE results in little decrease in aqueous concentration, since water is taken up at about the same rate as the chlorinated compounds. From this result we predict that phytoirrigation--the application of pumped contaminated groundwater to planted systems--will result in concentrations of the pollutants at the bottom of the root zone that are higher than permitted regulatory levels. Such plantations will be susceptible to loss of contaminants during rainfall events, possibly resulting in pollution of uncontaminated soil. Greenhouse studies of pollutant profiles in the media beneath poplar trees that were surface irrigated with TCE and CT confirmed that regulatory concentrations of these pollutants were not achieved in the root zone of the poplar; rather concentrations fell by less than 50%.  相似文献   

12.
Lateralisation, the different use of one or other side or appendix of the body, is basically determined by brain asymmetry which, in turn, is likely to be due to adaptive reasons. Several studies have been carried out on birds in general. However, birds of prey in particular, although they are very good candidates, have not been investigated from the sensory lateralisation point of view. In fact, many species scan for prey while perched and capture terrestrial prey with the feet, having at the same time the obvious necessity to keep their balance. This paper, therefore, investigates the existence of some sort of lateralisation in several species of both Falconiformes and Strigiformes temporarily in captivity. Attention is given to: (a) the direction of body rotation when perceiving a sound stimulus from behind the body and (b) the use of the feet when grasping a terrestrial prey. Lateralisation was found to be clearly present in both types of tests, although with some difference in its expression. In fact, almost every species tested rotated its body anti-clockwise, i.e. to the left, both in the first test and in repeated tests, with no noticeable difference between Falconiformes and Strigiformes. Also prey grasping showed a preferential use of one foot. Falconiformes preferred clearly to grasp the prey with one foot only in both the first test and in subsequent ones. Strigiformes, on the other hand, preferred using both feet, although a not insignificant proportion of individuals used one foot. Only the little owl seemed to have the tendency to prefer to use the right foot only, in a similar manner to Falconiformes. In fact, this bird is the most "diurnal" owl species among those tested, suggesting that lateralisation in footedness might be affected by adaptive constraints more than by phylogenetic similarities. Lateralisation, therefore, seems to be very widespread among birds of prey. Preferential use of the right foot also appears to be a general habit, and this is probably connected to the use of left hemisphere when manipulating food items.  相似文献   

13.
Cyathostoma lari Blanchard, 1849 is a nematode which parasitizes the orbital and nasal cavities of gulls (Laridae), the crow family (Corvidae) and occasionally other species of birds. It has not, apparently, been reported in birds of prey, although two other species, C. americana and C. brodskii , have been recorded in the air sacs of raptors in North America and the USSR.
This report describes infection by nematodes, provisionally identified as C. lari , in the orbital cavities of two kestrels ( Falco unnunculus ) and a common buzzard ( Buteo buteo ). A single specimen was also recorded in the lower eyelid of a sparrowhawk ( Accipiter nisus ). There was no evidence of pathogenicity in the kestrels and buzzard, but in the sparrowhawk the parasite was possibly associated with damage to the eyelid.  相似文献   

14.
Avian blood parasites have been intensively studied using morphological methods with limited information on their host specificity and species taxonomic status. Now the analysis of gene sequences, especially the mitochondrial cytochrome b gene of the avian haemosporidian species of Haemoproteus, Plasmodium, and Leucocytozoon, offers a new tool to review the parasite specificity and status. By comparing morphological and genetic techniques, we observed nearly the same overall prevalence of haemosporidian parasites by microscopy (19.8%) and polymerase chain reaction (PCR) (21.8%) analyses. However, in contrast to the single valid Leucocytozoon species (L. toddi) in the Falconiformes we detected 4 clearly distinctive strains by PCR screening. In the Strigiformes, where the only valid Leucocytozoon species is L. danilewskyi, we detected 3 genetically different strains of Leucocytozoon spp. Two strains of Haemoproteus spp. were detected in the birds of prey and owls examined, whereas the strain found in the tawny owl belonged to the morphospecies Haemoproteus noctuae. Three Plasmodium spp. strains that had already been found in Passeriformes were also detected in the birds of prey and owls examined here, supporting previous findings indicating a broad and nonspecific host spectrum bridging different bird orders.  相似文献   

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Summary 1. Sandwich terns(Sterna sandvicensis) of a colony in the Dutch Wadden Sea, which were seen dying in tremors and convulsions, were analysed for their contents of chlorinated hydrocarbon insecticides. These proved to be present in considerable concentrations.2. The concentrations found were compared to those present in chickens of hens, poisoned in the laboratory. The amounts present in the dying or dead Sandwich terns were high enough to cause their death.3. Tern eggs from different coastal places in Ireland, Great Britain, The Netherlands and West Germany were sampled and analysed for these compounds. The amounts of dieldrin, telodrin and endrin in the eggs from the first two countries were much lower than those in the eggs from the last two ones. The amounts of DDE were quite the same.4. Tern food fishes(Clupea sprattus, Clupea harengus andAmmodytes lanceolatus) were sampled in the Dutch Wadden Sea and analysed. They contained considerable amounts of chlorinated hydrocarbon insecticides.5. Mussels(Mytilus edulis) were sampled at a series of locations alongside the Dutch coast. The highest concentrations of the insecticides were found on places near the mouth of the river Rhine. Also telodrin, an insecticide not used in Europe, was found.6. A big insecticide producing industry near the mouth of the river Rhine was informed of these facts. Measures taken by this form resulted in a decrease of the amounts of telodrin in the coastal North Sea environment.
Rückstände von chlorierten Kohlenwasserstoff-Insektiziden im Lebensraum der Nordsee
Kurzfassung In einer großen Brutkolonie von Brandseeschwalben(Sterna sandvicensis) auf der Insel Griend im holländischen Wattenmeer war die Anzahl der Brutvögel von > 20 000 Paaren im Jahre 1955 auf etwa 1000 Paare im Jahre 1965 zurückgegangen. Viele Vögel wurden tot oder sterbend mit Krampfsymptomen aufgefunden. Organe und Blut dieser Vögel wurden auf ihren Gehalt an nerventoxischen Stoffen, insbesondere an chlorierten Kohlenwasserstoff-Insektiziden, untersucht. Die Konzentrationen wurden mit denen von Jungvögeln verglichen, die im Laboratorium auf künstliche Weise mit diesen Stoffen versehen worden waren und daran auch starben. Es konnte somit nachgewiesen werden, daß die in den Brandseeschwalben gefundenen Konzentrationen zum Tod der Tiere geführt haben. Die an verschiedenen Orten gesammelten Eier der Brandseeschwalben wurden ebenfalls untersucht. Eier aus den Niederlanden und aus Deutschland enthielten deutlich mehr Endrin, Dieldrin und Telodrin als Eier aus England und Irland. Verschiedene Fischarten(Clupea sprattus, Clupea harengus, Ammodytes lanceolatus), die von den Brandseeschwalben gefressen werden, wurden im holländischen Wattenmeer gesammelt und analysiert; sie enthielten beträchtliche Mengen an chlorierten Kohlenwasserstoff-Insektiziden. Der Herkunft dieser Stoffe wurde durch Untersuchungen von Miesmuscheln(Mytilus edulis) nachgegangen, die an verschiedenen Stellen entlang der holländischen Küsten gesammelt wurden. Die größten Insektizid-Konzentrationen wurden in Miesmuscheln gefunden, die aus dem Gebiet der Rheinmündung stammten. Einem dort gelegenen chemischen Werk, das diese Insektenvertilgungsmittel herstellt, wurden die Untersuchungsergebnisse mitgeteilt. Zugleich wurden geeignete Maßnahmen vorgeschlagen, um das Einleiten von insektizidhaltigen Abwässern zu verhindern. Augenscheinlich hat inzwischen die Konzentration einiger dieser Stoffe inMytilus edulis abgenommen.
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Conservation Genetics - The current and rapid anthropogenic environmental changes could disproportionately impact ecosystems, particularly when they affect species with critical roles in ecosystem...  相似文献   

18.
We studied the effects of removal of breeding nomadic avian predators (the kestrel, Falco tinnunculus and Tengmalm's owl, Aegolius funereus) on small mammals (voles of the genera Microtus and Clethrionomys and the common shrew, Sorex araneus) during 1989–1992 in western Finland to find out if these predators have a regulating or limiting impact on their prey populations. We removed potential breeding sites of raptors from five manipulation areas (c. 3 km2 each), whereas control areas had nest-boxes in addition to natural cavities and stick-nests. Densities of small mammals were monitored by snap-trapping in April, June, and August, and densities of mammalian predators (the least weasel, Mustela nivalis nivalis, the stoat, M. erminea and the red fox, Vulpes vulpes) by snow tracking in early spring and late autumn. The yearly mean number of raptor breeding territories was 0.2–1.0 in reduction areas and 3.0–8.2 in control areas. Breeding raptors alone did not regulate prey populations in the long term, but probably caused short-term changes in the population dynamics of both the main prey, the sibling vole (Microtus rossiaemeridionalis) and an alternative prey (the common shrew). The densities of an alternative prey, the bank vole (Clethrionomys glareolus) decreased in raptor reduction areas, most likely due to increased least weasel predation pressure in the absence of breeding avian predators.  相似文献   

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Sexual selection as a promoter of speciation has received much attention in recent years, but has produced highly equivocal evidence. Here, I test whether sexual conflict is related to species richness among genera in accipitrid birds of prey using phylogenetically controlled comparative analyses. Increased species richness was associated with both 'male-win' as well as 'female-win' situations, i.e. males being able to promote gene flow through mating or females being able to restrict gene flow through female choice. Species richness was higher when plumage differed between males and females and in polygynous breeding systems compared with monogamous ones. To assess the relative importance of sexual conflict and natural selection as correlates of species richness simultaneously, I also performed a multivariate analysis of correlates of species richness. Population density, plumage polymorphism, geographic range size and breeding latitude were predictors of species richness for birds of prey. These results stress the importance of both sexual and natural selection in determining species richness but with a clear overall emphasis on natural selection in birds of prey.  相似文献   

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