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1.
Migratory birds (swallow, Hirundo rustica; sand martin, Riparia riparia; house martin, Delichon urbica) caught in southern Moravia (Czechoslovakia) in 1984-87 were examined for arbovirus infections. Isolation experiments were carried out using blood samples of 183 birds (52 swallows, 107 sand martins, and 24 house martins). The results were negative. Serological examinations of 136 birds (36 swallows, 86 sand martins, and 14 house martins) were made by haemagglutination-inhibition test (HIT) using 6 arboviral antigens of the genera Alphavirus (Sindbis--SIN) and Flavivirus (tick-borne encephalitis--TBE, West Nile--WN) and of the family Bunyaviridae (Tahyna--TAH, Calovo, CVO, and Bhanja--BHA). Antibodies against all of the tested viruses were detected at different rates: SIN 2.9%, TBE 1.5%, WN 1.5%, TAH 4.4%, CVO 1.5%, and BHA 2.2%. The titres ranged from 1.20 to 1.80.  相似文献   

2.
Twelve species of keratin decomposers isolated from 923 samples of feathers, nests and pellets of 90 species of free-living birds were clustered in 4 "econs" (numerical ecological groups): (A) Artroderma tuberculatum, A. ciferrii, A. multifidum, A. cuniculi (associated with the birds nesting in hollows); (B) Ctenomyces serratus, Arthroderma quadrifidum, Chrysosporium evolceanui (moderately alkalophilic species associated with the birds having a frequent contact with the soil); (C) Chrysosporium keratinophilum, Aphanoascus fulvescens, Chrysosporium tropicum (alkalophilic and hygrophilic species); (D) Arthroderma curreyi, Aphanoascus terreus (the species common in water habitats and associated frequently with exoanthropic birds). Two simple numerical procedures were used and compared: (1) Jaccard's association coefficient, and S?rensen's complete linkage clustering; (2) Forbes's association coeficient adjusted with chi-square, and the 3-linkage clustering technique. The method (2) seemed to be more effective.  相似文献   

3.
新疆各类陆栖脊椎动物近 70 0种 ,占中国这一类动物种数的 32 %,其中鸟兽资源尤其丰富 ,计有 42 5种鸟类和 1 5 5种兽类 (哺乳类 ) ,占中国鸟兽种数的 31 %。本文主要以新疆三大山区———阿尔泰山、天山、昆仑 -阿尔金山地区鸟类和哺乳类动物的多样性及区系分布作综合性介绍和分析。根据实地考察和以往文献资料 ,新疆阿尔泰山区记录在 1 2 4种鸟类 ,其中古北界北方型鸟类 5 1种 (占 41 .1 %) ,中亚型鸟类 31种 (占 2 5 .0 %) ,广布种鸟类 2 7种 (占 2 1 .8%) ,其他类型1 5种 (占 1 2 .1 %) ,显出以北方型泰加林鸟类为主的鸟类区系特征 ;分布的 5 0种兽类 ,区系上以古北界北方泰加林为主 ,即北方型兽类占该山区种数的 5 2 %。天山山区记录的鸟类大约2 81种 ,北方型种类占绝对优势 ,即北方型 1 0 6种 (占 37.72 %) ,北方广布型 76种 (占 2 7.0 4 %) ,中亚型 39种 (占 1 3.88%) ,高地型 1 8种 (占 6.41 %) ,广布型 33种 (占 1 1 .74%) ,东北型 9种 (占 3.2 1 %)。兽类分布有 62种 ,北方型兽类区系占优势 ,有 30种 (占 48.40 %) ,广布型 1 2种 (占 1 9.40 %) ,中亚型 1 1种 (占 1 7.70 %) ,特有种 9种 (占 1 4.5 0 %)。昆仑—阿尔金山地区 96种鸟类中 ,中亚类型成份占 2 8.1 %,高地型成分占 2 6%,北方型成?  相似文献   

4.
Weed seeds present an agronomic threat, but are also an important food resource for wildlife in winter. Weed seed densities on the soil surface in winter were examined from 1999 to 2002 in 105 fields on three different farms in UK. The effect of the preceding crop, cultivation, position within the field and the application of seed for birds (bird seed) on surface seed abundance and species composition was tested. Six or fewer species comprised c. 80% of the weed seeds. By January of each study year, the densities of seeds important for farmland birds (key seeds) were 73% or 87% lower compared with early winter on two of the farms, but were stable on the third where seeds were incorporated through cultivation. At the edge and mid‐field, seed densities only exceeded 400 m?2 in 17%, 10% and 12% of fields for total, key and dicotyledonous seeds respectively. The preceding crop only affected seed densities at one site; stubbles of winter barley had fewer seeds compared with winter wheat or spring barley. Seed densities varied between the edge and mid‐field, but trends were inconsistent between sites. The density of the larger seeds (Atriplex patula, Viola arvensis, Polygonum aviculare and Chenopodium album) were reduced in fields receiving bird seed. The objectives of weed control and conservation may not be mutually exclusive because seed return was most reduced where the ground remained uncultivated through the winter, yet this also provided the best foraging opportunities for surface feeding seed predators.  相似文献   

5.
1984~1985年在四川西昌泸山德昌松毛虫严重为害的云南松林区,按每隔40~50米距离,挂放人工巢箱一个。检查400个巢箱的结果:益鸟招引率达70.2~80.7%,招引的鸟种主要有山麻雀、大山雀,绿背山雀和戴胜。挂箱后林内食虫鸟数较对照区增加64.3~75.0%,松毛虫密度下降83.3~96.4%。  相似文献   

6.
Two new species of the syringophilid mites (Acari: Syringophilidae) are described from quills of passeriform birds. Syringophilopsis faini sp. n. is described from Sylvia curruca (L.) (Sylviidae) and Syringophiloidus carpodaci sp. n. is described from Carpodacus erythrinus (Pall.) (Fringillidae). Characters are detailed that differentiate Syringophilopsis faini from three species of a new "turdus" group, and Syringophiloidus carpodaci from S. minor.  相似文献   

7.
A total of 150 nymphal Ixodes ricinus (L., 1758) (Acari: Ixodidae) from the Czech Republic were examined for Anaplasma phagocytophilum (Foggie, 1949) Dumler et al., 2001 by PCR using EHR521/747 primers: 22 of 50 pools were positive (minimum prevalence, 14.7%). However, sequencing of the PCR products did not show complete homology with A. phagocytophilum (91%) while the closest relationship (95%) was found to "Candidatus Ehrlichia walkefii". The results indicate a need for care in interpretation of Anaplasma PCR results and for PCR optimization for detecting A. phagocytophilum in ticks.  相似文献   

8.
We investigated incidences of Fusarium head blight (FHB) and concentrations of six mycotoxins (deoxynivalenol, nivalenol, 3-acetyldeoxynivalenol, T-2 toxin, HT-2 toxin and zearalenone) in wheat from 2010 to 2013. Field trials were conducted at the Experimental Station of Cultivar Testing in Chrz?stowo, Poland (53o11’N, 17o35’E). We examined the effects of four agronomic factors, including pre-crop type (corn, sugar beets and wheat), date of sowing (late autumn: November 8–December 9 or spring: March 29–April 19), fungicidal application (untreated or treated with two applications) and cultivar (Monsun, Cytra), on FHB index (FHBi) and mycotoxin levels in order to minimize the risk of wheat grain contamination by mycotoxins via integrated pest management methods. The dominant Fusarium species observed on wheat heads were F. culmorum, F. avenaceum (Gibberella avenacea) and F. graminearum (Gibberella zeae), at 21.1%, 17.2% and 7.1%, respectively. A monthly rainfall sum of 113.9 mm and a relatively low air temperature (monthly average 15.5 °C) resulted in the highest FHBi in untreated wheat (25.1%). Agronomic factors crucial for the FHB incidence were the pre-crop, fungicidal treatments and cultivar selection. In wheat planted after wheat or corn, the FHBi was higher compared with a pre-crop of sugar beet. A double application of fungicides at BBCH 30–32 with prothioconazole and spiroxamine and at a BBCH 65 with fluoxastrobin and prothioconazole effectively reduced the FHBi and mycotoxin concentrations, respectively, in grain. The cultivar ‘Cytra’ had a greater FHBi (10.4%) than ‘Monsun’ (4.6%), and grain infestations by Fusarium species were also greater in ‘Cytra’, at 16.5%, than in ‘Monsun’, at 11.2%. Untreated cv. Cytra grown after corn in spring produced grains with the highest amounts of the mycotoxins, deoxynivalenol, 3-acetyldeoxynivalenol, zearalenone and HT-2 (605, 103, 17.5 and 5.53 μg/kg, respectively). Total mycotoxin levels in wheat were correlated with five determinants: duration of the period between the end of flowering and the beginning of kernel abscission, FHBi, F. culmorum isolation, G. zeae isolation and Fusarium ratio (FR) as a % of total mould isolations. Although, the mean concentration of mycotoxins in grain did not exceed the maximum permissible values for unprocessed wheat our study suggests necessity to monitor and mitigate FHB risk for susceptible cultivars, when wheat spring sowing follows corn or wheat.  相似文献   

9.
BACKGROUND: Zinc phosphide baits are used for controlling pest rodents but are also highly toxic to other vertebrates. The base for rodent baits containing zinc phosphide is usually wheat kernels which are highly attractive to birds. In this study, wheat-based pellets of different shapes and colours without zinc phosphide were tested for their attractiveness for pigeons (Columba livia Gmelin) and Japanese quails (Coturnix japonica Temm. & Schleg.) in aviaries and for pigeons and corvids (Corvus monedula L., Corvus corone L., Pica pica L.) in the field. RESULTS: In aviaries, wheat was clearly preferred over other bait. In the field, some bait formulations were avoided by birds in certain conditions. However, no formulation was avoided consistently across species to lower the potential uptake of zinc phosphide below the LD(50) for highly susceptible bird species (8 mg kg(-1) body weight). The formulations that were not rapidly eaten by birds (blue granules, red lentil-shaped pellets) were not avoided consistently at low and high vegetative cover.CONCLUSIONS: The bait formulations tested may not considerably enhance the safety of birds when using zinc phosphide for rodent control. Field testing other combinations of bait colour and shape to minimise background contrast may result in bait with higher potential for bird protection.  相似文献   

10.
A total of 2,883 foreign students at the age of 18-30 years were examined for amoebiasis after their arrival to Czechoslovakia. Stool examinations revealed the presence of Entamoeba histolytica in 112 of them (3.9%). Students from 38 countries were found to be infected with this parasite. In a set of 2,064 students from these countries E. histolytica prevalence in stool was 5.4%. There were greater differences in the prevalence between individual countries inside a geographical region than between individual geographical regions. The highest E. histolytica prevalence in stool was found in students from tropical and southern Africa (6.7% of 745 examined) and the lowest in students from South-eastern Asia (3.1% of 321 examined). In a simple cross-section study, antibodies against E. histolytica were detected by enzyme-linked immunosorbent assay (ELISA) in the sera of 1,001 persons. Antibodies were detected in 7.9% of students at the following titres: 1:200 in 4.5%, 1:600 in 1.5%, 1:1,800 in 1.9%. Antibodies occurred more frequently in students carrying E. histolytica cysts (X2 = 14.9). Titre of ELISA antibodies in patients with confirmed liver abscess was higher than 1:1,800. counterimmunoelectrophoresis (CIEP) test was used for serum examinations of patients who had been demonstrated by ELISA to be seropositive and of those carrying E. histolytica cysts. In a set of 170 patients CIEP antibodies were also more frequent in those carrying E. histolytica cysts (X2 = 26.95). A comparison of the results of ELISA and CIEP tests in the same patients revealed that CIEP antibodies were more dependent on the actual parasitization with E. histolytica than ELISA antibodies.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

11.
We present a simulation study of the role of birds and egg pod predators in the population dynamics of the Senegalese grasshopper. The model was an energetics-driven ecosystem model that included a natural Sahelian grass, millet, grasshoppers, the egg pod predators bombyliidae and Tenebrionidae, and 24 species of birds that prey on grasshopper nymphs and adults. The model simulated the rain-dependent dynamics and migration along a five-location south–north transect in Niger and Senegal, and the main outputs were the grasshopper pressure on the transect, measured as accumulated transect grasshopper days, and the density of eggs ready to emerge the following rainy season. The model was calibrated using observations from transects in Niger (2003, 2004) and Senegal (2004).

When input data from Niger 2003 and 2004 were applied, simulated reductions in grasshopper pressure during the rainy season from egg pod predators and birds, respectively, were within a range of 18–25%, but taken together the overall reduction in grasshopper pressure ranged between 35 and 37%. Using input from Senegal (2004) the birds accounted for reductions of around 25%.

When the impact of the natural enemies was measured in terms of reduction in the density of eggs hatching the following year, the simulated impact of the egg pod predators ranged between 45 and 83% and that of the birds between 33 and 39%, and the two groups combined caused reductions between 60 and 75%.

Analyses of the sensitivity to the bird species, added one by one, showed ‘predator saturation’ along the Niger transects (with low grasshopper density) but not along the Senegal transect.

For Niger, the sensitivity analyses revealed Cattle Egret, Grey-headed Sparrow, Chestnut-bellied Starling, Buffalo Weaver, Sudan Golden Sparrow, Grey Hornbill, Red-billed Hornbill and Abyssinian Roller to be the most important individual species. For Senegal the top-five individual bird species were Village Weaver, Buffalo Weaver, Savile's Bustard, Grey-headed Sparrow and Abyssinian Roller.  相似文献   

12.
Pigeons, Bengalese finches, and Japanese quail were dosed with pure pp′DDT, and their tissues were examined for residues immediately after death, or following storage. DDD residues in livers extracted immediately after death were always low (<5% DDT concentration) and sometimes undetectable. Reductive dechlorination of DDT to DDD occurred postmortem, relatively repidly at 20°C (90% after 8 hr), but more slowly at ?10 and ?20°C. The conversion could not be attributed to bacterial action and was evidently due to processes operating within the cell under anaerobic conditions. During storage at ?12 to ?15°C, reductive dechlorination occurred in brain and in embryos, but did not occur to any significant extent in depot fat or in eggs without embryos. These findings raise questions about the importance of DDD as an in vivo metabolite in birds and other vertebrates. The interpretation of DDD residues in tissues from laboratory and field studies is discussed.  相似文献   

13.
本文综述了高效广谱杀虫剂克百威的使用风险及其农业应用价值。分析了它对我国东北地区国家重点保护鸟类可能造成的影响,研究发现,85%以上国家重点保护鸟类有较大可能受到克百威的危害,并分析讨论了拟采取的决策。  相似文献   

14.
Understanding how birds detect and react to deterrent methods which are employed to protect structures is important both for the effective control of property damage, and to ensure that human health and safety are not compromised. One such device is a shock strip that causes slight pain to birds when they use a perch. Our aims were to determine: (1) the efficacy of a shock strip to flocks of Brown-headed Cowbirds (Molothrus ater), and Rock Pigeons (Columba livia); (2) the length of time to extinction of effect; (3) whether members of a flock show a behavioural response to treatment; and (4) whether the birds habituate to the treatment. When activated, shock strips were effective in displacing birds from treated areas. Birds had to experience the treatment; there was no discernible indication of flock members reacting to affected birds. When strips were deactivated after an initial period of activation, birds required more than 2 hours to return to treated areas. No habituation was observed. Because birds had to experience the shock, reduced coverage of a structure or use of sham devices to lower costs is considered inadvisable.  相似文献   

15.
Methiocarb, a broad-spectrum carbamate insecticide, has shown efficacy in repelling birds from a variety of crops, especially fruit. To evaluate the hazards posed to wildlife, we reviewed laboratory studies of methiocarb toxicity and repeilency to birds and mammals and field studies of methiocarb treatments to fruit and sweet corn. Calculations revealed that birds encountering typical maximum residue levels found in treated crops would have to eat extremely large amounts of treated food to die and would in almost all cases be repelled or immobilized long before a lethal dose could be ingested. Results from feeding tests in laboratories support these calculations, as do the findings from 33 field studies in 28 locations. In spite of extensive searches and observations, only 14 dead birds were found in treated fields. Based on estimates from 26 studies, treated plantings averaged 15% loss of fruit to birds compared with 36% for nearby untreated plantings. We conclude that methiocarb, applied to fruit crops at 1–7 kg a.i. ha ?1, will not adversely affect birds.  相似文献   

16.
Chlorinated hydrocarbon pesticide burdens, especially those of DDT and its metabolites, have been determined for 19 species of small terrestrial migratory birds killed chiefly at Florida television towers from 1964 to 1973. All 128 samples were sorted into pools by species. All pooled samples except one contained DDE and often DDT and DDD; dieldrin was present in 60 of the samples; but no PCB's were detected. In small subsamples, sigma DDT (p,p'-DDT, p,p'-DDD, and p,p'-DDE) residues sometimes differed between males and females, adults and immatures, and northbound and southbound migrants but results of these comparisons were inconclusive. Sigma DDT burdens were highest in adipose tissue and much lower in liver and brain samples. Especially among birds taken since 1970 have the pesticide levels in adipose tissue been at low levels, generally less than 3 ppm sigma DDT. These low quantities are comparable to those quoted in other reports on birds of similar trophic levels. The insectivorous and/or partly granivorous birds feeding on or near the ground tended to have higher sigma DDT levels than did the more arboreal species.  相似文献   

17.

BACKGROUND

Birds have been shown to reduce pest effects on various ecosystem types. This study aimed to synthesize the effect of birds on pest abundance, product damage and yield in agricultural and forest systems in different environments. Our hypothesis is that birds are effective pest regulators that contribute to a reduction in pest abundance, enhancement of yield quality and quantity and economic profit, and that pest regulation may depend on moderators such as the type of ecosystem, climate, pest, and indicator (ecological or economic).

RESULTS

We performed a systematic literature review of experimental and observational studies related to biological control in the presence and absence of regulatory birds. We retained 449 observations from 104 primary studies that were evaluated through qualitative and quantitative analyses. Of the 79 studies with known effects of birds on pest regulation, nearly half of the 334 observations showed positive effects (49%), 46% showed neutral effects, and very few (5%) showed negative effects. Overall effect sizes were positive (mean Hedges’ d = 0.38 ± 0.06). A multiple model selection retained only ecosystem and indicator types as significant moderators.

CONCLUSION

Our results support our hypothesis that there is a positive effect of avian control of pests for each analyzed moderator and this effect was significant for both ecological and economic indicators. Avian regulation of pests is a potential effective approach for environmentally friendly pest management that can reduce pesticide use regardless of the context of implementation. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.  相似文献   

18.
Abstract

The common myna Acridotheres tristis Linn., the jungle crow Corvus macrorhynchus Wagner and the house crow Corvus splendens Viellot are the major pests of oil palm in India. Other birds like crow pheasant Centropus sinensis Stresmann, parrot Loriculus sp. and pariah kite Milvus migrans Sykes also feed on oil palm fruits. These birds feed on the fleshy mesocarp of the ripe fruits resulting in heavy fruit loss, significantly reducing oil yield. Gizzard and intestinal content analysis indicated that oil palm fruits are the major source of food for these birds. Observations on 1657 oil palm fruit bunches during 1985–86 revealed that 76% of the ripe bunches and 5.6% of the unripe bunches were damaged by birds. The damage by birds was either ‘partial’ or ‘complete’, where 40–50% and 80–100% respectively, of the individual fruit weight was lost. The partial fruit damage was more common in 130–160 day‐old bunches and the complete fruit damage increased after 150 days of fruit set. Fruit loss due to bird damage was higher in palms in the border area of the plantation (2.3 kg/bunch) than in the interior (1.3 kg/bunch). It is estimated that around 2.8 tonnes of fresh fruits/ha/yr, equivalent to 420 kg of palm oil, are lost due to bird damage.  相似文献   

19.
Brown rice is used as a bait-carrier for the avicide DRC-1339 (3-chloro-4-methylaniline) when baiting blackbirds (Icteridae). In March and April 1996 and 1997, we assessed non-target granivorous bird use of rice-baited plots placed in harvested corn and soybean fields in eastern South Dakota for 168 observation hours. In both years combined, we identified 10 and 14 granivorous species in corn and soybean fields, respectively. In 1996 (X = 0.2, SE = 0.04) and 1997 (X = 1.2, SE = 0.38), total numbers of granivores min(-1) were similar between crops (P > or = 0.322). In 1996, bird numbers were higher (P = 0.069) in rice-baited fields (X = 0.3, SE = 0.07) than in unbaited reference fields (X = 0.1, SE = 0.04). In 1997, bird numbers (X = 1.2, SE = 0.38) did not differ between treatments (P = 0.456). Our data show that small numbers of non-target birds visited the rice-baited plots. However, total number of different individual birds using the plots was unknown.  相似文献   

20.
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