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1.
Reproductive evaluations were conducted on 185 male cats representing eight endemic Latin American species that were maintained in 44 zoos and private facilities in 12 Latin American countries. Reproductive assessments (testicular measures, ejaculate quality, and blood testosterone/cortisol concentration) were used to establish normative values for large‐ and small‐sized cats in Latin American collections. Data also were analyzed using multiple regression to study the impact of proven breeder status, diet, and various animal housing combinations. Most felids (>95%) in the survey were of wild‐born origin, and <20% had produced offspring in captivity. Larger felids had bigger testes and produced more semen, but tended to produce low‐sperm‐density ejaculates. The ejaculates of small felids were more sperm‐concentrated, but contained fewer total spermatozoa. Sperm motility was unrelated to species size, and certain species (puma, margay, tigrina, and jaguarundi) consistently produced few (<40%) normal sperm forms. Across species, >50% of males had low sperm counts (<1 million total sperm per ejaculate). Among large cats (jaguars and pumas), proven breeders had larger (P<0.05) testes, greater semen volume, and more normal sperm than nonbreeders. Males on adequate diets had higher (P<0.05) circulating cortisol. Among small‐sized felids, proven breeders had higher (P<0.05) testosterone, and males housed alone or paired with a conspecific female had more (P<0.05) total sperm per ejaculate and greater (P<0.05) seminal and testicular volumes. Fifty‐nine ejaculates (potentially representing ~100 artificial insemination (AI) or 26,000 in vitro fertilization (IVF) procedures) were cryopreserved for a felid genome resource bank. In conclusion, breeding success and reproductive traits for many endemic felids in Latin American zoos appear to be suboptimal, and likely would benefit from improvements in diet and exhibitry. Technology transfer and continued training of zoo staff and scientists in Latin American countries are essential if these zoos are to achieve their tremendous conservation potential for felids and other threatened endemic species. Zoo Biol 22:421–441, 2003. © 2003 Wiley‐Liss, Inc.  相似文献   

2.
This paper investigates how different prioritizations of species for conservation can affect both the number of breeding individuals that receive protection and the distribution of conservation attention among different types of habitat. I use as a study example three red lists of the avifauna of Kanton Zürich in northern Switzerland. Species are weighted based on their placement in different red list categories to represent differences in species' relative conservation value. I examine how these weightings affect the number of breeding pairs benefiting from increasing conservation effort. Conservation effort is defined as the number of ranked land parcels that receive conservation attention, be it through habitat enhancement, protection, or other measures. I rank parcels' conservation value based on the number of weighted breeding pairs estimated for each parcel. Not surprisingly, the number of category-1, -2 and -3 breeding pairs that receive benefits varies greatly when different red lists are used. Changes in the relative conservation value of species in different categories influences both the number of breeding pairs and the number of parcels to receive conservation attention. The effect of increasing conservation effort on the number of breeding pairs and the proportion of each landscape type receiving attention also vary when different red lists and relative conservation values are used to determine conservation priorities. Use of the official red list published by a governmental body (Bundesamt für Umwelt, Wald und Landschaft, Bern, Switzerland) results in more emphasis on conservation in agricultural landscape than did use of either of the other two lists. The process of prioritization of sites for conservation should evaluate the effects of variation in both the relative conservation value of species and species categorization that may arise due to incomplete data and variation in opinion.  相似文献   

3.
The global decline of biodiversity makes it important to find affordable ways to conserve and restore habitats. Restoration is useful for conserving native grasslands, with passive restoration defined as either natural colonization or unassisted recovery. Grasslands in southeastern South America have been transformed into croplands and impacted by other human activities. We describe the first assessment of passive restoration as a management tool to conserve birds in the Pampa grasslands of Brazil. We compared bird species richness using coverage‐based rarefaction and extrapolation, applying PERMANOVA for composition, and the abundance of bird communities between sites undergoing passive restoration (PR) and sites with native grasslands (NG). We employed fitted generalized linear mixed models (GLMM) to quantify relationships between bird occurrence and vegetation structure and cover. We recorded 61 species of birds during our study (45 in PR and 46 in NG) and 762 individuals (333 in PR and 429 in NG). Of these species, 15 were restricted to PR and 16 to NG. Grassland specialists and threatened species were found in both PR and NG, and only vegetation height differed between PR and NG. We detected eight species of conservation concern, including three recorded only in PR, three only in NG, and two in both PR and NG. The absence of marked differences in species richness and composition of bird communities between passive‐restoration and native grasslands in our study suggests that grasslands in the process of passive restoration can provide habitat for many species of grassland birds and that passive restoration is an appropriate management tool for biodiversity conservation in Brazilian grasslands.  相似文献   

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Seed-borne pathogens are a daily issue for ex situ collection managers who try to solve it using various chemicals more or less harmful to the staff and the plant material stored. The most common physical method for seed sterilisation is moist heat, in contrast to dry heat which is used much less frequently. Consequently, the efficiency of dry heat as disinfection method and the behaviour of seeds undergoing this treatment are currently poorly known, especially for wild species. In this study, seed viability was estimated by performing germination tests according to standard procedures. Germination tests were conducted on 13,200 seeds from 66 wild species of temperate regions belonging to 22 different families. Results indicate that dry seeds exposed to 60°C during 1hour were less infected by seed-borne pathogens in 14% of the cases, whereas no change has been registered in the other cases. For all 66 studied species, no decrease in germination percentage was detected after the heat treatment. Given its positive effect on infection control without affecting seed viability, dry heat treatment as proposed here opens opportunities for seed bank managers, but also for the disinfection of herbarium collections.  相似文献   

7.
Plant conservation urgently needs a concept that would unify different aspects of population viability as parts of conservation methodology. Such unification is especially lacking for ex situ conservation. We introduce a novel conservation approach in which ex situ collections maintained in natural or semi-natural environment and preserving both neutral and adaptive genetic diversity are a part of a complementary ex situ–in situ conservation strategy. Our approach is the first that explicitly takes into account ecologically significant (i.e. adaptive) variation of plants in both ex situ and in situ conservation actions. Using this approach we provide detailed guidelines for (1) representative sampling of the populations; (2) collection maintenance; and (3) utilization for in situ actions.  相似文献   

8.
This paper discusses the role of microbial resource collections in the ex situ conservation of microbial diversity and, in particular, the activities of a recently completed Darwin Initiative project to facilitate collection, identification and exploitation of Indonesian microbial diversity. This helped revitalize the collection of the Lembaga Ilmu Pengetahuea Indonesia (Indonesian Institute of Sciences), LIPI, Research and Development Centre for Biology, Bogor, Indonesia. It is suggested that a focus on microorganisms beneficial to man is essential to enable ex situ collections to be a useful tool in the conservation and sustainable utilization of microbial diversity. This task is enormous and far beyond the capabilities of one collection and its achievement will necessitate a network of collections.  相似文献   

9.
Aim To examine the taxonomic uniqueness, range sizes, endemism and conservation status of southern temperate zone mammals and how factors impacting their conservation differ across hemispheres. Location Land surfaces of all continents (with the exception of Antarctica) and continental islands with an emphasis on the southern temperate hemisphere (land south of the Tropic of Capricorn). Methods We used data from the 2008 IUCN Red List of Threatened Species to characterize conservation status, threats and range sizes to compare northern and southern temperate zone mammals. We assessed the taxonomic uniqueness of the two regions as derived from the EDGE programme. We also conducted a gap analysis by overlapping mammal ranges with protected area coverages for temperate regions. Results Southern temperate species are phylogenetically more unique than in the Northern Hemisphere. The endemics have significantly smaller range sizes and are at a significantly greater risk of extinction (about 50% greater, with 24.7% of species being threatened versus 15.6% in the Northern Hemisphere). Finally, southern temperate endemics are significantly more likely to exist outside protected areas (13.38% versus 3.65%). Main conclusions The southern temperate zone harbours a unique fauna, attributed to the long isolation from the northern temperate zone. Temperate regions are heavily exploited for human activities, especially grazing and agriculture. The Southern Hemisphere is particularly susceptible to disturbance, given the small range sizes of its species and the low degree of protected area coverage. The scenario now is one of regions with numerous endemics under high threat from human activities.  相似文献   

10.
Using molecular genetic information to guide population management can improve the sustainability of species in captivity. However, empirical population genetics has not been commonly applied to species management programs in zoos. One limitation may be the availability of genetic resources (e.g., markers, primers, etc.) for species held in zoos. To assess the extent to which species held in zoos have been studied using population genetics in the wild, we conducted a systematic literature review of close to 8,000 papers. We synthesized information on the availability and scale of population genetics studies across amphibian, bird, mammal, and reptile species held in zoos, and discussed their potential for informing ex situ management. We found that more than half of the species in zoos (52%) already have some genetic markers described in the literature specific for them, or a congeneric species, that could be further developed to aid the management of zoo populations, and the accumulation of these resources has been steady over the past decades. Furthermore, the proportion of species with genetic resources is even higher (62%) for species that are being managed through a formal breeding program in zoos. Our study provides encouraging results for captive program managers interested in integrating population genetics into ex situ management strategies.  相似文献   

11.
Mcve.  JA 《生物多样性》1999,7(1):38-51
"Their strength, lightness, smoothness, straightness, roundness, and hollowness, the facility and regularity with which they can be split, their many different sizes, the varying length of their joints, the ease with which they can be cut and with which holes can be made through them, their hardness outside, their freedom from any pronounced taste or smell,their great abundance, and the rapidity of their growth and increase, are all qualities which render them useful for a hundred different purposes, to serve with other materials which require much more labour and preparation. The bamboo is one of the most wonderful and most beautiful productions of the tropics." (Alfred Russel Wallace, 1869).  相似文献   

12.
Tulipa cypria, a Cyprus endemic plant, is protected under local and international legislations and categorised as “Endangered” by IUCN. Detailed habitat and distribution information was previously limited, particularly for northern Cyprus. Our objective was to accurately map the distribution and to collect habitat, subpopulation and threat data to enable a conservation status reassessment at global and regional levels. We gathered all available data and conducted extensive surveys focusing on northern Cyprus in 2014–2015, identifying 17 extant subpopulations amounting to 7765 individuals and the loss of 2 historical subpopulations amounting to 3500 individuals. We infer a continuous decline in population size and identify the major cause to be habitat loss through agriculture, with 75% of global habitats and 100% of northern Cyprus habitats being affected by it. We update the global assessment to Endangered B1ab(iii, iv, v) + B2ab(iii, iv, v) and suggest regional assessments for northern Cyprus (Endangered B1ab(iii, iv, v) + B2ab(iii, iv, v)), UN Buffer Zone (Endangered D1) and southern Cyprus (Endangered B2ab(iii)). Conservation priorities identified include initiation of gene transfer and life history studies, population trend monitoring and exsitu conservation actions.  相似文献   

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14.
Sun P  Yu HH  Zhao XQ  Wang DH 《动物学研究》2011,32(5):561-565
行为是反映动物应对环境变化的最直接形式。动物可以根据周围环境条件的变化以及自身的生理状况来调整行为,异地放养是保护珍稀动物的有效方法,但必然会对其行为产生影响。为了探讨藏羚(Pantholops hodgsonii)对异地环境的行为学适应,对异地圈养藏羚的警戒行为进行了不同季节间的比较研究,采用全事件记录法和焦点动物取样法,记录和统计了异地圈养藏羚在冷季和暖季的警戒行为,进而推测其对人类干扰的行为适应性。研究结果表明,雌性和雄性藏羚的警戒时间及警戒比例(警戒时间占全天活动时间的比例)在暖季存在显著差异(警戒时间:Z=4.36,P<0.05;警戒比例:Z=4.559,P<0.05),而在冷季则无差异(警戒时间:Z=0.001,P>0.05;警戒比例:Z=0.0014,P>0.05);而季节差异对雌、雄性藏羚的警戒时间、警戒比例均具有极显著的影响(雄性-警戒时间:F=31.758,P<0.01;警戒比例:F=21.768,P<0.01;雌性-警戒时间:F=14.98,P<0.01;警戒比例:F=11.05,P<0.01);但是季节和性别对藏羚警戒行为的影响没有交互作用(Z=?0.576,P>0.05)。这些结果提示异地圈养藏羚警戒行为的变化可能是对陌生环境适应的结果。  相似文献   

15.
The only cost-effective way to control inbreeding in ex situ forest tree plantations is often to allocate trees in such a way that the possibility of close relatives mating is small and, consequently, inbreeding does not increase too much over time. The classical permutated neighbourhood methods look for the configuration in which no ramets of the same genet are planted in the surroundings (neighbourhoods) of a particular tree but deny the influence of more distant trees. Another limitation of these methods is that they cannot incorporate any other genetic (e.g. kinship) or ecological (e.g. phenology) information. We have developed a new method based on the minimisation of the global probability of generating inbred offspring for the whole population. Improvements of this method from the classical ones are: (i) it takes into account all the trees (whether near or far) and not only the neighbours; (ii) different pollen dispersal functions can be implemented, fitting the particularities of each species and population; (iii) it allows for the integration of all available information about the genetic relationship between trees; and (iv) it is flexible allowing for particular crosses to be banned or encouraged. The novel method showed a better performance than classical ones both for simulated data and a case study under a broad range of scenarios. Magnitude of the benefit depends on the actual and assumed parameters for the pollen dispersal function and the relationship between trees, but even in the simple case where only clone identity is considered some advantage can be obtained by implementing the new algorithm.  相似文献   

16.
滇南热带植物物种多样性的迁地保护   总被引:1,自引:0,他引:1  
本文论述了滇南热带植物多样性迁地保护区的建设与稀有濒危植物的保护。进行了种子贮藏与萌发、幼苗生长条件和不同栽培条件等试验以及生物学特性观察等。雨季成熟的大粒型种子一般不耐贮藏,中、小粒型种子较耐贮藏,细小种子耐贮藏。育苗中幼苗除强阳性树种不需遮荫外,大多数热带雨林树种幼苗和幼树期都需要一定的荫蔽条件才能生长良好。西双版纳热带植物的发芽、抽梢、开花高峰期都集中在日平均温达20℃左右的3月。大量开始落叶是在1~2月,3月为多数植物的落叶盛期。果实在干凉季(11~2月)成熟的占23.9%,干热季(3~5月)成熟的占36.4%,湿热季(6~10月)成熟的占40%。  相似文献   

17.
The wild potato germplasm of the series Acaulia maintained at the Centre for Genetic Resources, The Netherlands, currently consists of 314 accessions. This collection comprises seed samples of the species Solanum acaule (ssp. acaule, ssp. aemulans, ssp. palmirense and ssp. punae) and Solanum albicans collected from South America. In order to validate taxonomic classification, to investigate the extent of redundancy and to study the distribution of genetic diversity across the collection area, the entire collection was analysed with two AFLP primer pairs on two plants per accession. Within the entire sample a total number of 130 polymorphic bands were scored for the two primer pairs. An UPGMA cluster analysis grouped the majority of plants according to the species and subspecies. A total number of 16 misclassifications were identified, including four cases that did not seem to belong to the series Acaulia. Two accessions were found to consist of plants of different AFLP clusters. AFLP data also allowed the taxonomic classification of the subspecies of 97 accessions that previously were described as S. acaule only. For 126 accessions the two individuals studied displayed identical AFLP profiles. Forty six of these 126 accessions shared their profiles with both or single plants of other accessions. These were all tested for identical profiles for a third primer pair, resulting in 15 duplication groups consisting of a total number of 22 accessions and 14 single plants. Analyses of molecular variance (AMOVA) were performed to examine the distribution of genetic variation. Comparison of geographic distances between the collection site of plants and the number of AFLP polymorphisms revealed no consistent relationship between geographic distance and genetic diversity. AFLP analysis appeared to be an efficient method to verify taxonomic classification and to identify redundancies in the wild germplasm of the series Acaulia. Implications of the results for the ex situ conservation of wild potato germplasm are discussed. Received: 6 November 2000 / Accepted: 20 April 2001  相似文献   

18.
Species extinctions caused by the destruction and degradation of tropical primary forest may be at least partially mitigated by the expansion of regenerating secondary forest. However, the conservation value of secondary forest remains controversial, and potentially underestimated, since most previous studies have focused on young, single‐aged, or isolated stands. Here, we use point‐count surveys to compare tropical forest bird communities in 20–120‐year‐old secondary forest with primary forest stands in central Panama, with varying connectivity between secondary forest sites and extensive primary forest. We found that species richness and other metrics of ecological diversity, as well as the combined population density of all birds, reached a peak in younger (20‐year‐old) secondary forests and appeared to decline in older secondary forest stands. This counter‐intuitive result can be explained by the greater connectivity between younger secondary forests and extensive primary forests at our study site, compared with older secondary forests that are either (a) more isolated or (b) connected to primary forests that are themselves small and isolated. Our results suggest that connectivity with extensive primary forest is a more important determinant of avian species richness and community structure than forest age, and highlight the vital contribution secondary forests can make in conserving tropical bird diversity, so long as extensive primary habitats are adjacent and spatially connected.Abstract in Spanish is available with online material.  相似文献   

19.
We estimate the extinction probability of a large and decreasing population, the southern bluefin tuna. This tuna was listed as critically endangered by the World Conservation Union (IUCN) in 1996. However, the absolute population size is still large and the extinction probability within the next half century is negligible if the recent population decline rate does not increase in the future. IUCN’s criterion with respect to the population decline rate should be linked to the absolute population size, if this is estimated. Several methods estimating the probability of extinction conclude that the southern bluefin tuna population will be below 500 mature individuals within the next 100 years and may be listed as vulnerable. These analyses suggest that extinction risk assessment is useful for management action for taxa that still have large population and are rapidly decreasing.  相似文献   

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