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1.
Locomotor behavior and substrate use of cage-reared golden lion tamarins (Leontopithecus rosalia), newly released and free-ranging on the grounds of the National Zoological Park, were studied to determine if locomotion changed following exposure to naturalistic conditions. The animals employed a predominantly quadrupedal locomotor profile, incorporating leaping and vertical climbing to a lesser degree. There was no clear evidence of a change in locomotion due to the high degree of variability in these behaviors. The locomotor repertoire of the free-ranging group differed from that of groups occupying unenriched but relatively large conventional enclosures, indicating that whereas locomotion is plastic with respect to environment, substrate characteristics influence locomotor behavior and may promote stereotypical behavior. However, due to anatomical constraints, the locomotor repertoire tended to be less variable than substrate use. Similar behaviors were used in moving through a variety of habitat features in spite of strong associations between specific locomotor styles and substrate classes. © 1994 Wiley-Liss, Inc.  相似文献   

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Changes in species composition, stem abundance, and basal area of trees taller than or equal to 10 m in a medium altitude tropical rain forest at the Ngogo study area, Kibale National Park, Uganda are described for the period between 1975 and 1998 ( n  = 23 years). Two enumeration episodes were conducted in 263 plots of 5 m by 50 m during 1975–80 and 1997–98. During this period, species richness decreased by 3% (from 92 to 89). Species diversity (H') also declined slightly from 2.97 to 2.86. The number of trees recorded in the sample plots decreased by 8% (from 2545 to 2329), while basal area decreased from 49.48 m2 ha−1 to 48.68 m2 ha−1. However, stem abundance and basal area increased for some species.  相似文献   

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We analyzed mineral lick soils and non-mineral lick soils from the Serengeti National Park, the Konza Praine, and Yellowstone National Park The concentrations of 14 different elements considered important for ungulate nutrition were analyzed to determine the relative importance of Na vs other elements in attracting animals to lick areas Only Na was consistently higher in the mineral lick soils of the three ecosystems Mean Na concentrations were c 20x greater in Serengeti licks, 10x greater in Konza licks and 3x greater in Yellowstone licks compared to the respective non-lick soils Despite the numerous elements analyzed for this survey, our results suggest that Na is the primary element initiates mineral lick use in these widely separated ecosystems The widespread distribution of Na-deficient forage likely explains the importance of Na in most mineral licks  相似文献   

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The Yellowstone National Park bison herd is 1 of only 2 populations known to have continually persisted on their current landscape since pre-Columbian times. Over the last century, the census size of this herd has fluctuated from around 100 individuals to over 3000 animals. Previous studies involving radiotelemetry, tooth wear, and parturition timing provide evidence of at least 2 distinct groups of bison within Yellowstone National Park. To better understand the biology of Yellowstone bison, we investigated the potential for limited gene flow across this population using multilocus Bayesian clustering analysis. Two genetically distinct and clearly defined subpopulations were identified based on both genotypic diversity and allelic distributions. Genetic cluster assignments were highly correlated with sampling locations for a subgroup of live capture individuals. Furthermore, a comparison of the cluster assignments to the 2 principle winter cull sites revealed critical differences in migration patterns across years. The 2 Yellowstone subpopulations display levels of differentiation that are only slightly less than that between populations which have been geographically and reproductively isolated for over 40 years. The identification of cryptic population subdivision and genetic differentiation of this magnitude highlights the importance of this biological phenomenon in the management of wildlife species.  相似文献   

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A total of 15 species of echinoderms (one asteroid, seven ophiuroids, five echinoids and two holothurians) were recorded at the Cahuita National Park reef lagoon, between September and October 2003, using a 1 m2 quadrant. The sites with coral substrate and algae were the most diverse, while those with seagrass and sand were the least. Ophiuroids were the most abundant group with 170 individuals, asteroids were the least abundant. Adding other studies and reports of echinoderms to this study, a total of 23 species have been found at Cahuita National Park, which is the most diverse area on the Caribbean of Costa Rica. We report nine new echinoderm records for Costa Rica's Caribbean.  相似文献   

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Based on research conducted in Senegal in 2004, this field report focuses on the politics of access to land at the northern periphery of the Niokolo-Koba National Park, where a group of villages evicted from the national park were resettled in the 1970s. Conflicts over the allocation of land resurfaced in the 1980s, following the application of laws authorizing rural community councils to allocate use rights in village agricultural lands. The land claims of evicted villages were challenged by the rural council and local state authorities, who sought to define such claims as illegal or ambiguous based on exclusionary discourses of productive use of land, autochthony and citizenship. The politics of access to land at the northern periphery are shaped by land and administrative reforms undertaken since the end of colonial rule in Senegal and the on-going local transformation of authority and property relations under increasing commoditization and insecurity of land use rights.
Melis EceEmail:
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A new species of Penicillium Link ex Fries is described and illustrated. It is represented by twenty six isolates recovered from soil at twenty six different locations at the southern part of the Paul Kruger National Park in South Africa. It clearly differs from all species of the genus described so far among the Biverticillata-Symmetrica Section, and it is therefore described and proposed as a new taxon: Penicillium krugerii sp. nov.  相似文献   

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Geothermal soils near Amphitheater Springs in Yellowstone National Park were characterized by high temperatures (up to 70°C), high heavy metal content, low pH values (down to pH 2.7), sparse vegetation, and limited organic carbon. From these soils we cultured 16 fungal species. Two of these species were thermophilic, and six were thermotolerant. We cultured only three of these species from nearby cool (0 to 22°C) soils. Transect studies revealed that higher numbers of CFUs occurred in and below the root zone of the perennial plant Dichanthelium lanuginosum (hot springs panic grass). The dynamics of fungal CFUs in geothermal soil and nearby nongeothermal soil were investigated for 12 months by examining soil cores and in situ mesocosms. For all of the fungal species studied, the temperature of the soil from which the organisms were cultured corresponded with their optimum axenic growth temperature.  相似文献   

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Terrestrial gastropods at the National Zoological Park's Conservation and Research Center (CRC) near Front Royal, Virginia, were surveyed from June 1985 to May 1986, to assess their role in transmission of the meningeal worm, Parelaphostrongylus tenuis. A total of 670 gastropods representing 9 families and 18 species was collected. The slug Deroceras laeve accounted for 50.4% of the specimens collected. Parelaphostrongylus tenuis infections were found in 15 gastropods (2.2% prevalence) representing 5 species; 5 of the infected gastropods were D. laeve. New host records for this nematode are Ventridens collisella and Philomycus carolinianus. Infected gastropods were recovered from June through October 1985 and in May 1986. All 6 sampling locations yielded infected gastropods, suggesting this parasite is widely distributed at the CRC, and is therefore likely to continue to pose a serious threat to exotic ungulates maintained there for conservation and research purposes.  相似文献   

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Anthropogenic activities including recreation were known to cause disturbances to waterbirds in their natural habitat. The Mole National Park, which is considered the largest and oldest in Ghana, attracted significant number of tourists over the years, and consequently induced pressures and disturbances to waterbirds. Thus, there is a need to study the human-wildlife interactions and conflicts. This study established the species list of waterbirds at Mole between August 2015 and February 2016, assessed the nature and levels of human disturbance to the birds and determined the alert and flight initiation distances of selected species. A total of 29 waterbird species were recorded of which White-faced Whistling Duck was the most abundant. At a flush rate of 2.5 per hour with each flush lasting 34.0 s, waterbirds at the park spend 85.0 s/h as a result of flushing of which only 17.6 s/h was attributed to human disturbance. Majority of the flushes (70.5%) were caused by indeterminate factors but the potential adverse impact of human induced flushing and the need to minimize or prevent increased rates in the park was indicated by birds perceiving disturbance from tourist/staff to be of the same risk as predation. It was recommended that a setback distance based on the longest Alert Distance (120.8 ± 31.9 m) and Flight Initiation Distance (32.7 ± 23.8 m), both of which were recorded for the Grey Heron, should be considered in the management of the park’s wetlands.  相似文献   

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OBJECTIVE--To investigate the effectiveness of computer based and manual district and unit information systems for identifying hospital deaths eligible for reporting to the National Confidential Enquiry into Perioperative Deaths (NCEPOD). DESIGN--Prospective six to 10 week study of hospital (death register, immediate coding of medical records) and district information systems followed by six month assessment after modification to entry of data. SETTING--Acute units within Lewisham and North Southwark Health District. PATIENTS--All 290 patients dying in hospital during the six weeks, for whom the medical records were obtainable in 231. MAIN OUTCOME MEASURES--Sensitivity and specificity of the information systems in ascertaining eligible surgical deaths (patients dying in hospital who had during 30 days previously had a surgical procedure while under the care of a consultant in a surgical specialty) tested against validated list of screened medical records. RESULTS--Of 231 medical records, 30 (12 from Lewisham, 18 from North Southwark) met the national inquiry''s criteria. The computer based systems of both units detected less than 60% of eligible deaths (sensitivity 53%, specificity 83%); the death register detected about 60% (sensitivity 61%, specificity 89%); manual systems detected all eligible deaths. Subsequent modification to ensure immediate coding of records into the computerised systems during follow up failed to show any improvement. IMPLICATIONS--Routine hospital information systems may miss up to half the deaths eligible for NCEPOD.  相似文献   

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Foos KM  Sheehan KB 《Mycologia》2011,103(6):1208-1215
Pilobolus, a widely distributed coprophilous fungus, grows on herbivore dung. Species of Pilobolus traditionally are described with imprecise morphological characteristics potentially leading to misidentification. In this study we used PCR analysis of taxonomically informative sequences to provide more consistent species identification from isolates obtained in Yellowstone National Park. We collected Pilobolus park-wide from six taxa of herbivores over 9 y. Multiple transfers of single sporangium isolates provided pure cultures from which DNA was extracted. Sequence analysis of internal transcribed spacer (ITS) regions of DNA that code for rRNA genes were used to distinguish among similar species. We describe several species of Pilobolus associated with herbivores in various habitats, including two species not previously reported, P. heterosporus and P. sphaerosporus. Our results show that phylogenetic species identification of Pilobolus based on sequence analysis of pure culture isolates provides a more reliable means of identifying species than traditional methods.  相似文献   

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 Roots of 40 taxa of higher plants (Pteridophyta, Spermatophyta) from two alpine study sites in Denali National Park and Preserve in central Alaska were examined for their mycorrhizal colonization. We observed ectomycorrhizae on six species: Betula nana, Salix reticulata, Salix polaris, Salix arctica, Polygonum viviparum, and Dryas octopetala. Seven taxa, Cassiope tetragona, Empetrum nigrum, Ledum palustre subsp. decumbens, Ledum palustre subsp. groenlandicum, Loiseleuria procumbens, Vaccinium uliginosum and Vaccinium vitisidaea (all Ericales), had ericoid mycorrhizae. One species, Arctostaphylos alpina, formed a typical arbutoid mycorrhiza. Two species (Sibbaldia procumbens and Aconitum delphinifolium) showed well-developed VA mycorrhizae, whereas three species of plants (Lycopodium clavatum, Silene acaulis and Oxytropis scammaniana) had vesicles, but no arbuscules. The roots of 11 other plants (Lycopodium clavatum, Lycopodium selago, Silene acaulis, Gentiana algida, Lupinus arcticus, Oxytropis scammaniana, Pedicularis langsdorffii, Pedicularis capitata, Pedicularis verticillata, Artemisia sp. and Carex bigelowii) had a variety of intracellular colonizations which are referred to as dark septate fungi. No mycorrhizae were found on 12 other plants: Equisetum arvense, Equisetum variegatum, Lycopodium alpinum, Polygonum bistorta, Saxifraga hieracifolia, Saxifraga hirculus, Astragalus alpinus, Pedicularis kanei, Petasites frigidus, Carex podocarpa, Carex microchaeta and Poa arctica. A possible ecological role of dark septate fungi is discussed. Accepted: 4 August 1995  相似文献   

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