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1.
Noninvasive methods using genetic markers have been suggested as ways to overcome difficulties associated with documenting the presence of elusive species. We present and assess a novel, reliable and effective molecular genetic technique for the unequivocal genetic identification of faeces from the endangered Iberian lynx (Lynx pardinus). From mitochondrial DNA (mtDNA) cytochrome b and D-loop region sequences, we designed four species-specific primers (for products 130-161 bp long) that were considered to be likely to amplify degraded DNA. We compared two DNA extraction methods, various DNA amplification conditions and the robustness and specificity of the primer pairs with 87 lynx samples from 5 potentially different lynx populations and with 328 samples of other carnivore species. The utility of the identification technique was tested with faeces of different ages, with faeces from controlled field experiments, and with faeces collected from locales with possible lynx populations from throughout the state of Andalusia, Spain (8052 km2). Faecal mtDNA extraction was more efficient using PBS wash of the faeces instead of a faeces homogenate. Our assay increased from 92.6 to 99% efficiency with a second amplification and a reduction in template concentration to overcome polymerase chain reaction (PCR) inhibition. Our assay never produced false positives, and correctly identified all lynx faeces. Of 252 faeces samples of unknown species collected throughout Andalusia, 26.6% (from three different areas) were classified as Iberian lynx, 1.4% showed evidence of PCR inhibition and 1.2% were of uncertain origin. This method has proven to be a reliable technique that can be incorporated into large-scale surveys of Iberian lynx populations and exemplifies an approach that can easily be extended to other species.  相似文献   

2.
1985~2009年,在长白山自然保护区及其周边地区采用野外样线调查和社会访问调查的方法,对猫科动物种群数量变化及影响因素进行了研究.结果表明,长白山自然保护区记载的东北虎(Pantheratigris)、远东豹(P.pardus)、猞猁(Felis lynx)和豹猫(F.bengalensis)4种猫科动物中,野外调...  相似文献   

3.
Summary The coenecium of Rhabdopleura is a tube that surrounds the zooid. It is secreted by the cephalic shield of the zooid and contains three sorts of fibres in an electron lucent matrix. One of the fibre types contains a double helix of fine fibrils. Preliminary histochemical investigations suggest that the fibres may be keratinous.I wish to thank Professor J. Z. Young F.R.S. for enthusiastic advice and encouragement. Dr. R. Bellairs generously provided the facilities for electron microscopy. Dr. A. J. Southward and Dr. A. Stebbing of the Plymouth Marine Biological Laboratory generously gave of their time and expertise, and helped me to obtain and identify the specimens. Dr. R. Willis and Miss Marion Dennison assisted with the preliminary stereoscopic electron microscopy. Mr. R. Moss gave excellent technical and photographic assistance.  相似文献   

4.
Winter recreation is a widely popular activity and is expected to increase due to changes in recreation technology and human population growth. Wildlife are frequently negatively impacted by winter recreation, however, through displacement from habitat, alteration of activity patterns, or changes in movement behavior. We studied impacts of dispersed and developed winter recreation on Canada lynx (Lynx canadensis) at their southwestern range periphery in Colorado, USA. We used GPS collars to track movements of 18 adult lynx over 4 years, coupled with GPS devices that logged 2,839 unique recreation tracks to provide a detailed spatial estimate of recreation intensity. We assessed changes in lynx spatial and temporal patterns in response to motorized and nonmotorized recreation, as well as differences in movement rate and path tortuosity. We found that lynx decreased their movement rate in areas with high‐intensity back‐country skiing and snowmobiling, and adjusted their temporal patterns so that they were more active at night in areas with high‐intensity recreation. We did not find consistent evidence of spatial avoidance of recreation: lynx exhibited some avoidance of areas with motorized recreation, but selected areas in close proximity to nonmotorized recreation trails. Lynx appeared to avoid high‐intensity developed ski resorts, however, especially when recreation was most intense. We conclude that lynx in our study areas did not exhibit strong negative responses to dispersed recreation, but instead altered their behavior and temporal patterns in a nuanced response to recreation, perhaps to decrease direct interactions with recreationists. However, based on observed avoidance of developed recreation, there may be a threshold of human disturbance above which lynx cannot coexist with winter recreation.  相似文献   

5.
A study is made of the dune system at Tentsmuir Point National Nature Reserve, Scotland, using transects crossing the vegetation zonation. Principal Components Analysis and tabular ordination are used to analyse the data, and an attempt is made to relate the results obtained to the dynamics of the system. The effects of different management regimes are considered, and it is concluded that the establishment of pine on the area has the largest effect on the development of the vegetation. Reduction in grazing pressure by rabbits is found to increase species diversity slightly, but has no major influence as yet on vegetation development. While some information on the dynamics of the vegetation can be inferred, the problems involved in this are considered to be large, and the study raises a number of questions to be studied in greater detail. It is concluded that permanent plots would be the most effective method to employ.Nomenclature follows Clapham, Tutin & Warburg (1962) for vascular plants, Watson (1968) for bryophytes, and Duncan (1970) for lichens.We should like to thank Dr. R. A. H. Smith of the Nature Conservancy Council for her assistance and permission to work on Tentsmuir Point N. N. R., and Mr. J. G. Young, then warden at Tentsmuir for his help at the start of the project. We are grateful to Dr. R. Meutzelfeldt for computational advice. In addition, one of us (R.J.H.) would like to thank Dr. E. van der Maarel and Dr. R. S. Clymo for their tuition during the Nordic Council for Ecology course Numerical Methods in Vegetation Analysis' in Lund, September, 1979.  相似文献   

6.
R. J. Hobbs 《Plant Ecology》1984,57(2-3):129-136
Studies on a long-term experiment on Calluna-Eriophorum bog indicate that the length of time between management fires affects the post-fire development. A short rotation (every 10 years) results in increased dominance by Eriophorum spp. while a long rotation (every 20 years) results in greater abundance of Calluna vulgaris after fire. Variations in post-fires species abundances are related to pre-fire stand composition coupled with the patchy distribution of regeneration centers of rhizomatous species. The usefulness of burning this vegetation type in management for herbivore grazing is questioned.Nomenclature follows Tutin et al. (1964 80) for vascular plants. Smith (1978) for mosses, Watson (1981) for liverworts and Hawksworth, James & Coppins (1980) for lichens. Following common practice. Calluna vulgaris is referred to simply as Calluna. Acknowledgements. I thank M. Raves and the Nature Conservancy Council for permission to work on Moor House National Nature Reserve and for the use of data from Reserve Records, V. J. Hobbs for field assistance, and Prof. C. H. Gimingham for help and advice during the study. I also thank all who worked at Moor House for creating a pleasant working environment. The long-term experiment was planned by Dr R. J. Elliot and analyzed initially by Dr G. I. Forrest.  相似文献   

7.
D. G. Hewett 《Plant Ecology》1985,62(1-3):441-447
A brief review of mowing and grazing of sand dune vegetation introduces the first results of the use of these management techniques at Newborough Warren National Nature Reserve, Anglesey, north Wales. In the mowing experiments, plots are mown one (May), twice (May and July), three times (May, July and September) and five times (May, June, July, August and September).The grazing experiment has the equivalent of one or two animals to three-quarter acre paddocks (0.3 ha) which are grazed for one third, two thirds or for the whole year.Mean numbers of species per plot, and Lotus corniculatus have increased in both sets of experiments whereas Arrhenatherum elatius has declined. Other species do not show clear-cut changes. Both methods provide practical means of maintaining a short turf, but the long-term effects of mowing may not be beneficial to the vascular plant flora. Grazing can however provide a crop as well as a desirable flora although manpower and capital costs may limit its use by conservationists.Nomenclature follows Clapham, A. R., Tutin, T. F. & Warburg, E. G. (1962), Flora of the British Isles, 2nd ed. Cambridge University Press, London.A large grazing experiment can not proceed without the help and advice of many people. The Nature Conservancy Council has allowed the establishment of the grazing and mowing experiments at Newborough Warren National Nature Reserve. The staff of the North Wales region of NCC have encouraged and aided the work in many ways. Mr W. D. Martin, Mr R. A. Bennett, Mr L. C. Colley and the Estate Workers merit special thanks. Dr J. Hodgson, late of the Grasslands Research Institute, now with the Hill Farming Research Organisation and Mr P. Rothery (ITE) gave useful, practical and statistical advice at the planning stages of the grazing experiment. Mr R. J. C. MacMullen assisted with the field survey in 1982 and preparation of the data for computer analysis. Dr D. Moss (ITE) has provided statistical advice and computations. Professor F. T. Last and Dr C. Milner, my senior officers in ITE, have been especially helpful with advice and encouragement.  相似文献   

8.
In the fossil deposits of the Late Pleistocene ( c . 115 000–11 500 years ago), five felid species are recorded in Europe: the wildcat Felis silvestris , Eurasian lynx Lynx lynx , Iberian lynx Lynx pardinus , leopard Panthera pardus and cave lion Panthera leo spelaea . In the Holocene, Europe was colonized by F. silvestris , L. lynx and L. pardinus as well as the lion Panthera leo . The status of P. pardus in post-glacial Europe is unknown. So far, only sparse records indicate that P. pardus survived into the early Holocene. During the Late Glacial, both L. lynx and L. pardinus occurred on the Iberian Peninsula. However, from the Holocene, only the Iberian lynx is recorded in this region. There are subfossil records that indicate that L. pardinus also occurred in central and western France until c . 3000 years ago. Surprisingly, with reservations on the determination of the bones (by J. Altuna), both lions and cave lions seem to be recorded in the Iberian Peninsula in the Late Glacial. There are published records of the lion P. leo in the northern Iberian Peninsula from the early Holocene. However, its presence in Europe on the basis of subfossil records was proven initially from the Atlantic period. In Ponto-Mediterranean regions of Europe, the lion is recorded from the Atlantic to the younger sub-Atlantic.  相似文献   

9.
Even though the Eurasian lynx is a less controversial species than the wolf or brown bear, poaching remains a major cause of lynx mortality in Europe, potentially threatening population expansion in key areas. Our study was designed to explore the attitude of hunters and other stakeholders (students of secondary forestry schools and University forestry faculties) towards lynx and their experience with illegal killing of lynx in the Czech Republic. Self-administered questionnaires were addressed to local hunters and to students in 2001 and again in 2015. The survey in 2001 was conducted in two separate hunting regions of Bohemia, one where lynx have been artificially reintroduced and another in which lynx have become established through natural colonisation. In 2015 the survey was extended to two further areas where lynx have re-established themselves through natural colonisation, in the east of the Czech Republic. Altogether 415 and 922 questionnaires were completed in 2001 and 2015, respectively. The attitude of hunters towards lynx was not affected by hunting region, lynx population density or nature of the population (human re-introductions vs natural recolonisation), but attitudes became more negative in 2015 than they had been in 2001. The majority of hunters still believed that lynx had negative effects on other wildlife and 27% stated that they do not wish to co-exist with lynx. Half of secondary school students and a third of tertiary students still believe that lynx threaten roe deer stocks, even though roe and red deer are present at high density and cause extensive damage in commercial forestry. Hunters as well as forestry students had first-hand knowledge about illegal hunting of lynx. The proportion of hunters admitting to having poached lynx themselves was 10% with the proportion of repeated illegal kills made by the same person increasing between 2001 and 2015. Population modelling suggested that at least 25% of the population might be poached annually, sufficient to restrict population growth and further expansion of lynx distribution.  相似文献   

10.
11.
The epidemiology of Ancylostoma spp. was studied in the endangered Iberian lynx (Lynx pardinus) in the Do?ana National Park, south-west Spain. Faecal samples were collected throughout a complete annual cycle (August 1997 to September 1998). The overall egg prevalence of Ancylostoma spp. was 57.8%. The pattern of abundance of Ancylostoma spp. eggs in faeces was overdispersed. Juvenile lynx demonstrated a statistically higher prevalence and abundance of Ancylostoma spp. than in adults. These levels of egg output (maximum 21195 epg), as previously reported in free ranging large felid cubs, could be close to disease involvement. The potential pathogenicity of hookworms and the influence of individual and ecological factors on hookworm transmission in the Iberian lynx from the Do?ana National Park population are discussed.  相似文献   

12.
Toxothrix trichogenes (Chol.) Beger et Bringmann was found in iron-containing spring water, in tap water, and in a small forest pond of lower Michigan.The use of a partially submerged microscope for continuous observation of undisturbed underwater Aufwuchs on glass slides resulted in the rediscovery of the actualToxothrix organisms: long, often U-shaped and highly flexible bacterial filaments. Direct observation of their growth and movements on immersed glass slides revealed the production byToxothrix trichomes of several slime strands which were typically twisted. Fan-shaped slime structures and parallel tracks were directly seen to be formed by U-shaped organisms as a result of the forward gliding and rolling of their center portion. Chemical iron deposition onto the individual slime strands of such tracks rendered these rigid and brittle; the iron deposition also proceeded in the absence of living trichomes.The trichomes disintegrated rapidly and completely during laboratory observations, althoughToxothrix trichomes were kept viable for several months in refrigerated state. Disintegration under the normal light microscope explains their absence from most stranded sheaths studied by previous investigators.Agricultural Experiment Station Article No. 4935.The investigations were supported by an NSF Institutional Grant for Science to J. T. Staley and by the Michigan State University, Agricultural Experiment Station. J. M. Krul acknowledges gratefully a travel grant from the Ministerie van Landbouw en Visserij. We are thankful for the interest in and help with this work by Dr. G. Lauff, Kellogg Biological Station (Hickory Corners, Mich.) and Mr. W. A. Lemmien, MSU Experimental Forest, Augusta, Mich. Dr. G. A. Zavarzin, Moscow, contributedToxothrix samples and helped with his interest and discussions.MSU Kellogg Biological Station Contribution No. 189  相似文献   

13.
Olfactory signals constitute an important mechanism in interspecific interactions, but little is known regarding their role in communication between predator species. We analyzed the behavioral responses of a mesopredator, the red fox (Vulpes vulpes), to an olfactory cue (scat) of an apex predator, the lynx (Lynx lynx) in Bia?owie?a Primeval Forest, Poland, using video camera traps. Red fox visited sites with scats more often than expected and the duration of their visits was longer at scat sites than at control sites (no scat added). Vigilant behavior, sniffing and scent marking (including over-marking) occurred more often at scat sites compared to control sites, where foxes mainly passed by. Vigilance was most pronounced during the first days of the recordings. Red fox behavior was also influenced by foxes previously visiting scat sites. They sniffed and scent marked (multiple over-marking) more frequently when the lynx scat had been over-marked previously by red fox. Fox visits to lynx scats may be seen as a trade-off between obtaining information on a potential food source (prey killed by lynx) and the potential risk of predation by an apex predator.  相似文献   

14.
This study aimed to test how the sex and reproductive status of Eurasian lynx influenced their use of 'attractive sinks'– habitats with high prey density and high mortality risks. Locations of 24 Eurasian lynx Lynx lynx were obtained by radio-telemetry in a mixed forest and agricultural habitat in south-eastern Norway. Roe deer, the major food source of lynx in the study area, occurred at higher densities closer to areas of human activity and infrastructure. Proximity of lynx locations to human activity and infrastructure was used as a risk index because the most common causes of death among Scandinavian lynx were of anthropogenic origin. This study shows that distances from lynx locations to human activity were significantly greater for females with newborn kittens than for males, but this decreased with kitten age. The data suggest that this response to human activity is influenced by the reproductive strategies of males and females, and might explain male-biased human-induced mortality in this study and in carnivores more generally.  相似文献   

15.
Looking for the Iberian lynx in central Spain: a needle in a haystack?   总被引:1,自引:0,他引:1  
The Iberian lynx Lynx pardinus has suffered a dramatic reduction in its range throughout the Iberian Peninsula and at present is one of the most endangered mammals in the world. The latest studies report that, out of the 48 breeding areas that existed in 1990, only two populations are left in southern Spain. As a consequence, some of the formerly largest populations, such as Montes de Toledo (central Spain), are to all intents and purposes regarded as extinct. To determine the current distribution of Iberian lynx outside the two recognized populations, we surveyed five different areas where the species is considered extinct and collected 581 faeces for the genetic identification of the species. We identified 18 samples as belonging to Iberian lynx in four out of the five areas studied, providing clear evidence for the presence of lynx in central Spain. In some areas the species was detected repeatedly at different localities and on different dates, indicating a regular occurrence of an unknown number of individuals. The conservation implications of these results are discussed in terms of the genetic importance of the individuals found and future reintroductions of the species from an ongoing captive-breeding programme.  相似文献   

16.
Abstract: Coyotes (Canis latrans) and Canada lynx (Lynx canadensis) are sympatric throughout much of the lynx's southern range. Researchers and managers have suggested that the presence of compacted snowmobile trails may allow coyotes to access lynx habitat from which they were previously excluded by deep, unconsolidated snow. This could then allow coyotes to more effectively compete with lynx for snowshoe hares (Lepus americanus), the lynx's primary prey. We investigated how coyotes interacted with compacted snowmobile trails by conducting carnivore track surveys and by snow tracking adult coyotes (4 M, 8 F) in areas of western Montana, USA, with both documented lynx presence and recreational snowmobile use. Coyotes remained in lynx habitat having deep snow throughout the winter months. They used compacted snowmobile trails for 7.69% of their travel distance and traveled on them for a median distance of 124 m. Coyotes used compacted forest roads (5.66% of total travel) and uncompacted forest roads (4.62% of total travel) similarly. Coyotes did not travel closer to compacted snowmobile trails than random expectation (coyote x̄ distance from compacted trails = 368 m, random expectation = 339 m) and the distance they traveled from these trails did not vary with daily, monthly, or yearly changes in snow supportiveness or depth. However, they strongly selected for naturally shallower and more supportive snow surfaces when traveling off compacted snowmobile trails. Coyotes were primarily scavengers in winter (snowshoe hare kills composed 3% of coyote feed sites) and did not forage closer to compacted snowmobile trails than random expectation. The overall influence of snowmobile trails on coyote movements and foraging success during winter appeared to be minimal on our study area. The results of this study will allow land managers to better assess the effects of snow-compacting activities on coyotes and lynx.  相似文献   

17.
The classic fur trade records on Canadian lynx (Lynx canadensis) have rarely been analysed in direct conjunction with data on its principal prey, the snowshoe hare (Lepus americanus). Comparable long-term data for hare exist only for a region south of Hudson Bay. We fitted a bivariate log-linear time-series model to this hare and lynx data to disentangle the within- and between-population interactions of these species. To reduce problems with fur returns being non-normal and non-linearly related to abundance, we transformed the fur returns to a normal distribution based on sample quantiles. The estimated effect on next year’s lynx abundance of a 1% increase in current hare abundance was a 0.23% (SE = 0.05) increase in lynx. Conversely, a 1% increase in current lynx abundance corresponded to a 0.46% (SE = 0.12) decrease in next year’s hare abundance. This contrasts with some earlier studies. However, these studies mixed hare data from south of Hudson Bay with lynx totals for all of Canada. Despite this asymmetry of interaction strengths, coefficients of determination were similar for hare versus lynx and lynx versus hare, because hare abundance varies more than lynx. Both species showed clear intraspecific density-dependence of about equal strength. A 1% increase in current abundance increased next year’s abundance by about 0.75%. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

18.
Book Reviews     
《Journal of Phytopathology》1987,120(4):376-376
book reviewed in this article
Herzog, H.: Source and Sink during the reproductive period of wheat. Development and its Regulation with Special Reference to Cytokinins.
Hoffmann, W., A. Mudra, W. Plarre , Lehrbuch der Züchtung landwirtschaftlicher Kulturpflanzen. Band 2: Spezieller Teil. 2. neubearbeitete Auflage, Hrsg. Fischbeck, G., W. Plarre und W. Schuster.
Sorauer, P. , Handbuch der Pflanzenkrankheiten. 7., völlig neugestaltete Aufl. Bd. I. Die nichtparasitären Krankheiten, 5. Teil: Meteorologische Pflanzenpathologie; Witterung und Klima als Umweltfaktoren; Kälte und Frost. Bearb. von Prof. Dr. W. Larcher, Dr. H. Häckel unter Mitwirkung von Prof. Dr. A. Sakai.
Plumb, R. T., and J. M. Thresh (Eds.) , Plant Virus Epidemiology:
Frederiksen, R. A. (ed.) , Compendium of sorghum diseases.
Azzi, A., U. Brodbeck and P. Zahler (eds.) , Enzymes, Receptors and Carriers of Biological Membranes.
Schubert, R. (Hrsg.), Lehrbuch der Ökologie.
Harborne, J. B. , Introduction to Ecological Biochemistry.  相似文献   

19.
ABSTRACT We investigated seasonal patterns in resource selection of Canada lynx (Lynx canadensis) in the northern Rockies (western MT, USA) from 1998 to 2002 based on backtracking in winter (577 km; 10 M, 7 F) and radiotelemetry (630 locations; 16 M, 11 F) in summer. During winter, lynx preferentially foraged in mature, multilayer forests with Engelmann spruce (Picea engelmannii) and subalpine fir (Abies lasiocarpa) in the overstory and midstory. Forests used during winter were composed of larger diameter trees with higher horizontal cover, more abundant snowshoe hares (Lepus americanus), and deeper snow compared to random availability; multilayer, spruce-fir forests provided high horizontal cover with tree branching that touched the snow surface. During winter, lynx killed prey at sites with higher horizontal cover than that along foraging paths. Lynx were insensitive to snow depth or penetrability in determining where they killed prey. During summer, lynx broadened their resource use to select younger forests with high horizontal cover, abundant total shrubs, abundant small-diameter trees, and dense saplings, especially spruce-fir saplings. Based on multivariate logistic-regression models, resource selection occurred primarily at a fine spatial scale as was consistent with a sight-hunting predator in dense forests. However, univariate comparisons of patch-level metrics indicated that lynx selected homogenous spruce-fir patches, and avoided recent clear-cuts or other open patches. Given that lynx in Montana exhibit seasonal differences in resource selection, we encourage managers to maintain habitat mosaics. Because winter habitat may be most limiting for lynx, these mosaics should include abundant multistory, mature spruce-fir forests with high horizontal cover that are spatially well-distributed.  相似文献   

20.
Summary Freeze-fracture of the distal accessory flexor muscle reveals the presence of randomly distributed arrays of P- and E-face particles. The particles are arranged in regularly spaced rows which parallel one another and, in general, the long axis of the muscle fiber. P- and E-face arrays differ in their structure and are apparently complementary. A model explaining the apparent interrelationship of the P- and E-face arrays is presented. The functional significance of the arrays is not known.We thank J. Pearce for technical assistance and Dr. R.R. Shivers, Department of Zoology, University of Western Ontario for his provision of freeze-fracture facilities. This work was supported by grants from the Natural Sciences and Engineering Council of Canada and the Muscular Dystrophy Association of Canada to C.K.G.  相似文献   

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