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71.
Marshall AJ Salas LA Stephens S;Nardiyono Engström L Meijaard E Stanley SA 《American journal of primatology》2007,69(2):212-219
The Indonesian province of East Kalimantan is home to some of the largest remaining contiguous tracts of lowland Dipterocarp forest on the island of Borneo. Nest surveys recently conducted in these forests indicated the presence of a substantial population of Eastern Bornean orangutans (Pongo pygmaeus morio) in the Berau and East Kutai regencies in the northern half of the province. The Sangkulirang Peninsula contains extensive limestone karst forests in close proximity to the lowland Dipterocarp forests inhabited by orangutans in these regencies. Orangutans have been sighted in these limestone karst forests, but the importance of this forest type for orangutans has been unclear. Therefore, we conducted 49 km of nest surveys in limestone karst forest to obtain the first quantitative estimates of orangutan densities in this habitat, and walked 28 km of surveys in nearby lowland Dipterocarp forests for comparison. We also gathered basic ecological data along our transects in an attempt to identify correlates of orangutan abundance across these habitat types. Undisturbed limestone karst forests showed the lowest orangutan densities (147 nests/km(2), 0.82 indiv/km(2)), disturbed limestone forests had intermediate densities (301 nests/km(2), 1.40 indiv/km(2)), and undisturbed lowland Dipterocarp forests contained the highest density (987 nests/km(2), 5.25 indiv/km(2)), significantly more than the undisturbed limestone karst forests. This difference was not correlated with variation in liana abundance, fig stem density, or stump density (an index of forest disturbance). Therefore, other factors, such as the relatively low tree species diversity of limestone karst forests, may explain why orangutans appear to avoid these areas. We conclude that limestone karst forests are of low relevance for safeguarding the future of orangutans in East Kalimantan. 相似文献
72.
Biological control of agricultural pests relies on knowledge of agroecosystem functionality, particularly when affected by the use of mass‐produced biological agents. Incorporating pre‐ and/or post‐release information such as genetic diversity and structure on these agents using molecular‐based approaches could advance our knowledge of how they perform in agroecosystems. We evaluated the population genetics of Macrolophus pygmaeus, the most widely used predatory mirid against many arthropod pests of greenhouse crops in the Mediterranean region, using the mitochondrial Cytb sequence and microsatellite data, and population genetics and phylogeny approaches. We investigated commercially mass‐produced insects (i.e., commercial insects either mass‐reared in the laboratory for many generations, or purchased by farmers and released in the greenhouses) and “wild” insects (i.e., that occur naturally outside or are collected in nature for release in the greenhouses). The mirids were mainly collected in agroecosystems in which solanaceous plants are grown in northern Spain, southern France and Greece. Both molecular markers and approaches distinguished 2 genetically differentiated populations. The less genetically diverse population, hereafter named the “commercial” strain included all individuals from laboratory mass‐rearings and most releases of commercially bred individuals. The most genetically diverse population mainly comprised individuals originating from noncultivated environments, or from releases of “wild” individuals. Rare examples of hybridization between M. pygmaeus from the 2 populations were observed and asymmetric gene flow was revealed. These findings provide new insights into what happens to M. pygmaeus released in the agroecosystems we studied, and show that it is possible to monitor some commercial strains. 相似文献
73.
【目的】脐腹小蠹Scolytus schevyrewi Semenov是白榆的钻蛀性害虫之一,为找到对脐腹小蠹的高致病力虫生真菌菌株。【方法】通过室内喷雾法研究了5株虫生真菌菌株对脐腹小蠹幼虫的致病力,结合各菌株菌落直径、孢子萌发率、产孢量和菌落生长速率4个培养特征,筛选到Bb773和Pc546 2株优良的菌株,在此基础上,进一步对这2株菌株的几丁质酶、蛋白质酶和荧光素二乙酸酯(FDA)水解酶活性进行了测定。【结果】菌株Bb773和菌株Pc546在浓度为1×107孢子/mL悬浮液处理后,10 d的后脐腹小蠹幼虫的校正死亡率分别达96.67%和90.00%,致死中时分别为3.61 d和4.18 d。菌株Bb773的几丁质酶、FDA水解酶和蛋白质酶活性在接种后第2~10天均高于菌株Pc546,2株菌株蛋白质酶活性差异均达到了显著水平(P<0.05)。【结论】确定了菌株Bb773在脐腹小蠹害虫生物防治中具有潜在的应用价值。 相似文献
74.
75.
S. Robert 《American journal of primatology》1986,10(2):109-117
Mirror image reactions of two infant apes, a female chimpanzee (Pan troglodytes) and a male orangutan (Pongo pygmaeus), born at the Zoo de Vincennes and the Jardin des Plantes of Paris, France, respectively, were studied and compared with those of children. Self-recognition was also tested following 46.5 hours of mirror exposure by application of red marks on parts of the body invisible to the animal without the aid of the mirror. Results indicated that the behavior of the two young apes followed a developmental trend similar to that of human babies. At the end of the study, the female chimpanzee (11 months of age) expressed social behavior, searched for the image behind the mirror, and showed interest in imaged movement. The orangutan (2 years and 5 months old) had begun to test movement synchronism and to display self-directed behaviors. The tests of self-recognition yielded negative results in both animals. 相似文献
76.
Why do orangutans leave the trees? Terrestrial behavior among wild Bornean orangutans (Pongo pygmaeus wurmbii) at Tuanan,Central Kalimantan
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77.
78.
C.‐C. Chen K.J.‐C. Pei C.‐M. Yang M.‐D. Kuo S.‐T. Wong S.‐C. Kuo F.‐G. Lin 《Journal of medical primatology》2011,40(1):2-5
Background Natural infection of hantavirus in orangutans has never been reported. Methods Enzyme‐linked immunosorbent assays (ELISA), Indirect immunofluorescence assay (IFA), and RT‐PCR were used to diagnosis a suspected case in a pet orangutan in southern Taiwan. Results Although the RT‐PCR result was negative, the high IgG titer in the beginning and its dramatic drop after treatments suggested a recent Seoul‐type hantavirus infection. Conclusions Hantavirus transmission and its potential damage to wild orangutans should not be overlooked. 相似文献
79.
Biruté M. F. Galdikas 《International journal of primatology》1988,9(1):1-35
Previously, wild orangutan feeding and ranging behaviors have been described only from populations in hilly or mountainous
regions. The Tanjung Puting study focuses on an orangutan population in a swampy lowland area near sea level. Tanjung Puting
also differs from other areas in the virtual absence of large figs, which are significant orangutan food sources elsewhere.
During a 4-year period and 6804 hr of observation, focal orangutans were recorded in 11,338 foraging bouts accounting for
3805 hr. Composition and phenology of the forest habitat were documented. The orangutans were predominantly frugivorous, with
fruit-eating accounting for 61% of the foraging time. However, the overall variety in their diet was remarkable; 317 different
food types have been identified, including fungus, insects, and honey. Orang-utans were strongly opportunistic foragers, with
the composition of their diet varying markedly from month to month. During most months orangutans fed on a complex mix of
fruit, leaves, bark, insects, and small vines. During some months fruit was not the major component of the diet. All orangutans
foraged in both the dry-ground mixed dipterocarp forest and the peatswamp forest habitats found in their ranges. Adult males
and females utilized different proportions of certain resources in their diets. Prime adult males also ranged further per
day and spent more time on the ground than prime adult females. At Tanjung Puting contact with other orangutans usually increased
a focal orangutan’s day length, day range, and amount of time spent moving. This suggests that foraging alone maximized each
orangutan’s foraging returns by minimizing the day range traveled. Orangutan solitariness is the result of a large body size
and of a predominantly frugivorous and opportunistic diet. 相似文献
80.