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1.
The helminth community of the Mediterranean gull (Ichthyaetus melanocephalus) from the Calabria region in southern Italy was examined. Ten species of helminths, including 2 cestodes (Alcataenia larina and Tetrabothrius cylindraceus), 4 digeneans ( Aporchis massiliensis , Brachylaima fuscatum, Cardiocephaloides longicollis, and Ornithobilharzia canaliculata), and 4 nematodes (Eucoleus contortus, Capillaria sp., Cosmocephalus obvelatus, and Paracuaria adunca), were found. The Mediterranean gull represents new host records for A. larina, A. massiliensis, B. fuscatum, and E. contortus; all species, except C. longicollis and O. canaliculata, constitute new locality records. The gastrointestinal helminth community of I. melanocephalus consisted of 9 species but, at the infracommunity level, species richness, diversity, and total helminth abundance are among the lowest reported from any gull species. Two cestode species accounted for 81% of all helminth specimens found.  相似文献   

2.
Helminth communities of 171 fledged white-winged doves (Zenaida asiatica asiatica) from the expanding eastern population in Texas (USA) were examined from hosts collected 11 June to 19 September 1997 within their historical range, new breeding periphery, and an intermediate area. Eleven helminth species, representing 435 individuals, were found. Helminths occurred in three microhabitats, of which the small intestine was the most commonly occupied. Nematodes dominated numerically (76% of total worms), followed by cestodes (17%), and trematodes (7%). Infracommunities were species-poor; the most complex infracommunity consisted of three helminth species, which occurred in three host individuals, followed by two species that occurred in 13 hosts. The remaining 155 doves had one (70) or no (85) species. The overall helminth component community was species-poor and was dominated by Ascaridia columbae which occurred in 26% of the white-winged doves and accounted for 65% of all helminth individuals. Prevalence and abundance of A. columbae varied by geographic region and host age, but not by host sex. Helminth component communities varied by geographic region, host age, and host sex. These differences were primarily attributable to unique occurrences of uncommon species within specific host subpopulations. Results suggest that the white-winged doves' multimodal regional abundance pattern, sympatry with other columbids, and granivorous diet may be more important in shaping helminth community structure than the influences often associated with geographic range expansion.  相似文献   

3.
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   

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Mercury levels in feathers of nestling (162 broods) and fully-grown individuals (n = 48) were studied. Within feather variation was considerable in many individual flight feathers. In juv. ospreys the mercury levels in distal parts of secondary coverts were significantly higher than those in proximal parts (p<0.01). In total feathers, the mercury levels were higher and their variations were larger in ad. than in juv. accipiters. Various irregularities in the mercury levels in different parts of the plumage of a bird seem to support the hypothesis that the mercury in the food eaten during feather growth considerably affects the mercury levels of the feathers, while the regular trends mainly support the hypothesis that the amount of mercury stored in body tissues is a determining factor of plumage levels. The importance of these factors seems to vary depending particularly on the age of the birds. From the result of this study, feathers as indicators of environmental mercury pollution should preferably be from nestlings. Small feathers are preferable to larger ones, and total feathers should be analysed rather than only parts of them.  相似文献   

6.
In this paper the results of a study on the composition and the distribution of the plant communities in three coastal areas of southern Apulia are presented. A total of about 180 vegetation relevés were performed following the Braun-Blanquet phytosociological method. Vegetation data were analysed using both classification (UPGMA, similarity ratio) and ordination methods (including Non-metric Multidimensional Scaling (NMS) and Detrended Correspondence Analysis (DCA). The relevés are distributed in the following classes: Molinio-Arrhenateretea, Phragmito-Magnocaricetea, Juncetea maritimi, Sarcocornietea fruticosae, Saginetea maritimae, Thero-Salicornietea, Helianthemetea guttati. Detailed information about structure and zoning of the detected plant communities are here provided. Two new associations, belonging to the Alkanno-Maresion nanae alliance (microphytic ephemeral plant communities growing on sandy soils, Helianthemetea guttati class) have been described here, both in the “Torre Guaceto” site. The area of “Le Cesine” showed the highest total number of plant communities, while the “Saline di Punta della Contessa” site revealed the largest number of Sarcocornietea fruticosae plant communities.  相似文献   

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The current study presents the ostracod communities recovered from 26 shallow waterbodies in southern Kenya, combined with an ecological assessment of habitat characteristics. A total of 37 waterbodies were sampled in 2001 and 2003, ranging from small ephemeral pools to large permanent lakes along broad gradients in altitude (700–2 800 m) and salinity (37–67 200 µS cm?1). Between 0 and 12 species were recorded per site. Lack of ostracods was associated with either hypersaline waters, or the presence of fish in fresh waters. Three of the 32 recovered ostracod taxa, Physocypria sp., Sarscypridopsis cf. elizabethae and Oncocypris mulleri, combined a wide distribution with frequent local dominance. Canonical correspondence analysis on species–environment relationships indicated that littoral vegetation, altitude, surface water temperature and pH best explain the variation in ostracod communities. Presence of fish and water depth also influence species occurrence, with the larger species being more common in shallow waterbodies lacking fish. Based on Chao’s estimator of total regional species richness, this survey recovered about two-thirds (60–68%) of the regional ostracod species pool. Scanning electron micrographs (SEM) of the valve morphology of 14 ostracod taxa are provided, in order to facilitate their application in biodiversity and water-quality assessments and in palaeoenvironmental reconstruction.  相似文献   

10.
The main goal of this study was to evaluate the relative influence of season, year of study, host body size, and host sex on abundance of helminth species parasitic in the frog Scinax nasicus. A total of 273 frogs was collected between December 2004 and November 2006 over all seasons in Corrientes City, Province of Corrientes, Argentina. Helminth community included 21 taxa, and was dominated particularly by larval trematodes. Infected frogs harboured a maximum of 7 species. Host sex and season played no significant effect in determining infracommunity parasite species abundance. Similarly, species richness was similar for both host sexes, and across time (year and season). However, occurrence of the parasites Opisthogonimus sp. 2 and Travtrema aff. stenocotyle greatly varied over time. Host body size was the main factor for determining infrapopulation structure of Centrorhynchus sp. Species richness was significantly and positively correlated with host body size. Strong associations were observed mainly between metacercariae of some species. The transmission strategies of parasites suggest that this hylid acquires infections by ingestion of infective larvae and through direct contact with larval parasites from aquatic and terrestrial habitats.  相似文献   

11.
The helminth community composition and structure of 6 species of columbids residing in south Texas are reported and compared herein. Sixty individuals of the following species, rock pigeons (Columba livia [RP]), mourning doves (Zenaida macroura [MD]), Eurasian collared-doves (Streptopelia decaocto [ECD]), white-winged doves (Zenaida asiatica [WWD]), and common ground doves (Columbina passerina [CGD]), and 48 Inca doves (Columbina inca [ID]) were collected during the summer of 2006 and examined for helminths. Twelve helminth species were found (9 nematodes and 3 cestodes), representing 486 individuals. Nematodes numerically dominated the component community in all host species. Overall, helminth prevalence was similar among host sex within all dove species. However, prevalence of Skrjabinia bonini and Hymenolepis sp. in RPs was significantly different among host age groups (P = 0.01, P = 0.0002, respectively). Likewise, prevalence of Killigrewia delafondi was higher (P = 0.0001) in adult WWDs. Based on percent similarity and Jaccard's coefficient of community indices, helminth component communities were dissimilar, and the number of shared helminth species varied among host species. Data from this study suggest that the environment surrounding preferred host habitat and foraging strategies of each host species is the driving force behind helminth component communities. This study emphasizes the importance of examining co-occurring hosts at both local and regional scales to elucidate helminth community structure and patterns.  相似文献   

12.
Forty-eight scaled quail (Callipepla squamata) were collected during August 2002 at Elephant Mountain Wildlife Management Area in Brewster County, Texas, and examined for helminths. Eight species of helminths were found (5 nematodes and 3 cestodes), representing 2,811 individuals. Of these species, Gongylonema sp., Procyrnea pileata, and Choanotaenia infundibulum are reported from scaled quail for the first time. Prevalence of Aulonocephalus pennula, Gongylonema sp., Oxyspirura petrowi, Physaloptera sp., P. pileata, C. infundibulum, Fuhrmannetta sp., and Rhabdometra odiosa was 98, 2, 56, 4, 60, 2, 25, and 35%, respectively. Aulonocephalus pennula numerically dominated, accounting for 88% of total worms. Statistical analyses were performed on the 5 species with > or = 25% prevalence using the after-hatch-year host sample (n = 38). Prevalence of P. pileata was higher (P = 0.049) in females than in males and higher (P = 0.037) in the sample collected from the site that had spreader dams (berms 1-2 m high and 4-55 m long constructed in varying sizes to catch and retain rainfall) than the control site (no spreader dams). Higher rank mean abundance of A. pennula and O. petrowi (P = 0.0001 and P = 0.0052, respectively) was found in the host sample collected from the site that had spreader dams than the control site. A host gender-by-collection site interaction (P = 0.0215) was observed for P. pileata. Findings indicate that scaled quail are acquiring indirect life cycle helminths in arid western Texas habitats.  相似文献   

13.
The present study was carried out in a protected wooded area, which is part of the Parco Regionale Gallipoli Cognato Piccole Dolomiti Lucane, one of the most important ecological reserves in southern Italy. From April 2010 to April 2011, 212 birds, comprising 22 species from 12 families, were captured and examined for ticks. A total of 75 (35.4?%) birds were found infested by ticks, with 451 ticks being collected. All ticks were identified as Ixodes ricinus, of which 241 (53.4?%) were larvae and 210 nymphs (46.6?%). The highest intensity of infestation was found in April 2010, when 117 ticks were retrieved on 25 birds. No ticks were found on birds (n?=?5) netted in December 2010. High infestation rates were recorded on blackbirds (Turdus merula) (90 %; 29 birds examined) and on mistle thrushes (Turdus viscivorus) (100?%; 2 birds examined). The highest intensity of infestation by larvae was found on wrens (5.6 larvae/bird) and by nymphs on mistle thrushes (11.5 nymphs/bird). Temperature and number of hours of light showed to influence the activity of larvae and nymphs. These data support the notion that birds may be responsible for the heterogeneous distribution of I. ricinus in Europe, thus playing a role in the epidemiology of certain tick-borne pathogens.  相似文献   

14.
This study was carried out to determine chewing louse species of wild birds in the Ria Formosa Natural Park, located in southern Portugal. In addition, the hypothesis that bird age, avian migration and social behaviour have an impact on the louse prevalence was tested. Between September and December of 2013, 122 birds (belonging to 10 orders, 19 families, 31 genera and 35 species) captured in scientific ringing sessions and admitted to the Wildlife Rehabilitation and Investigation Centre of Ria Formosa were examined for lice. Twenty-six (21.3%) birds were found to be infested with at least one chewing louse species. The chewing lice identified include 18 species. Colonial birds (34.9%) and migratory birds (29.5%) had statistically significant higher prevalence than territorial birds (6.8%) and resident birds (13.1%), respectively. This paper records 17 louse species for the first time in southern Portugal: Laemobothrion maximum, Laemobothrion vulturis, Actornithophilus piceus lari, Actornithophilus umbrinus, Austromenopon lutescens, Colpocephalum heterosoma, Colpocephalum turbinatum, Eidmanniella pustulosa, Nosopon casteli, Pectinopygus bassani, Pseudomenopon pilosum, Trinoton femoratum, Trinoton querquedulae, Craspedorrhynchus platystomus, Degeeriella fulva, Falcolipeurus quadripustulatus, Lunaceps schismatus. Also a nymph of the genus Strigiphilus was collected from a Eurasian eagle-owl. These findings contribute to the knowledge of avian chewing lice from important birds areas in Portugal.  相似文献   

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Synopsis Trophic relationships among marine fishes in a nearshore sand environment off southern California showed that the species were distinguished by specific morphological and behavioral features adapted to capture the prey, and evade the predators, that were characteristic of that habitat. Species that foraged primarily by day included the serranidParalabrax clathratus, the embiotocidEmbiotoca jacksoni, and the labridsHalichoeres semicinctus andSemicossyphus pulcher. Primarily nocturnal foragers included the ophidiidChilara taylori, the sciaenidUmbrina roncador, the embiotocidsCymatogaster aggregata andHyperprosopon argenteum, and the pleuronectidPleuronichthys coenosus. The bothidCitharichthys stigmaeus regularly fed during both day and night. The major predatory threat to these fishes came from the bothidParalichthys californicus, which was primarily diurnal. In combination, these fishes possessed an array of behavioral and morphological feeding adaptations that closely matched the feeding opportunities present in that habitat. Not only did they consume, as a group, every species identified in samples of organisms from the environment (except the holoplankton, as discussed), they exploited these species over virtually the entire size ranges present. We infer from these circumstances that the species composition of fishes in this community was strongly influenced by the presence of specific feeding opportunities.  相似文献   

17.
We investigated the parasite communities of introduced Iberian hares (Lepus granatensis) and native European hares (Lepus europaeus) in southern France, where Iberian hares were introduced locally 20 yr ago as a game animal. Parasite communities of sympatric populations of the two hare species and of allopatric populations of European hares were compared. Iberian hares in France harbored a depauperate community of parasites relative to the population in its native habitat in Spain. European hares in areas of sympatry also were infected by Nematodiroides zembrae, which normally infects Iberian hares on their native range.  相似文献   

18.
Cytotaxonomic study in the order Falconiformes (Aves)   总被引:1,自引:0,他引:1  
Karyotypes of six species of birds of the order Falconiformes are presented. The chromosomes of three of these, Neophron percnopterus, Butastur teesa (family Accipitridae) and Falco chicquera (family Falconidae) are described for the first time. The systematic position of these birds are discussed in relation to the karyological characters of other diurnal birds of prey.  相似文献   

19.
The paper describes an investigation of parasite richness in relation to host life history and ecology using data from an extensive survey of helminth parasites (cestodes, trematodes and nematodes) in Soviet birds. Correlates of parasite richness (number of parasite species per host species) were sought among 13 life-history variables, 13 ecological variables and one non-biological variable (number of host individuals examined) across a sample of 158 species of host. A statistical method to control for the effects of phylogenetic association was adopted throughout. Parasite richness correlates positively with the number of hosts examined (sample size) in all three parasite groups. Positive correlations (after controlling for the effects of sample size) were also found between host body weight and parasite richness for trematodes and nematodes, but not for cestodes.
A number of ecological variables were associated with parasite richness. However, when the effects of sample size and body weight were controlled for, only a single significant correlation (an association between trematode richness and aquatic habitat) remained. Similarly, a number of significant correlates of parasite richness were found among the life-history variables examined. Though several of these were robust to the confounding effects of sample size, all could be explained by the co-variation between life-history traits and body weight among the host species under investigation.  相似文献   

20.
For species that rely on visual cues to detect prey items, increasing the structural complexity of a patch can greatly influence forager behaviour through consequent reductions in prey detectability and accessibility. These effects are likely to manifest themselves in terms of foraging site selection and there is plentiful evidence for preferential site selection for a suite of taxa. However, the underlying effects of habitat structure on foraging behaviour, which are likely to drive these observed site selections, are much less well understood. We present the results of two studies designed to quantify the effects of vegetation structure on prey detectability and accessibility to avian invertebrate feeders and granivores on farmland. There was a significant negative relationship between potential prey detectability and both distance and vegetation height in cereal crops and stubbles for Northern Lapwings Vanellus vanellus . The interscan distance travelled by Lapwings differed significantly between habitats, with longer distances travelled in cereal crops and harrowed compared with ploughed soil and grasses. The peck rate, head-up rate and mean search period of foraging Chaffinches Fringilla coelebs were not affected by increasing vegetation structure but forager mobility was significantly reduced. We hope that by quantifying the effects of vegetation structure on prey detectability and accessibility we can highlight the importance of considering these factors, as well as prey abundance, when developing management strategies for farmland birds.  相似文献   

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