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1.
The role of zoos in conservation has evolved. Additional roles that zoos can play in conservation include monitoring live wildlife use (one of the main threats for many species). Zoos in many parts of the world are offered animals by the public and are required to receive animals confiscated by the authorities. By quantifying these animals, zoos can monitor live wildlife use rates and trends and obtain relevant information on the environment of a region which can assist in situ conservation management. Zoos are sometimes forced to receive unwanted animals from the public or the authorities. Receiving these animals is a burden for zoos. Agreements between zoos and governments are important to take care of these animals and to optimize the use of conservation resources. It is not possible or desirable to maintain all donated and seized animals. The International Union for Conservation of Nature and Natural Resources provides useful guidelines on what to do with them. In all cases, species conservation should take precedence over individual animal welfare. These issues are illustrated with data collected at Zoológico Regional Miguel Alvarez del Toro (ZOOMAT) in Chiapas, southern Mexico. Zoo Biol 24:115–124, 2005. © 2005 Wiley‐Liss, Inc.  相似文献   

2.
This paper reviews a way of investigating health and welfare problems in captive wild animals (e.g., those in zoos, aviaries, aquaria, or aquaculture systems) that has great potential, but to date has been little used: systematically comparing species with few or no health and welfare issues to those more prone to problems. Doing so empirically pinpoints species‐typical welfare risk and protective factors (such as aspects of their natural behavioral biology): information which can then be used to help prevent or remedy problems by suggesting new ways to improve housing and husbandry, and by identifying species intrinsically best suited to captivity. We provide a detailed, step‐by‐step “how to” guide for researchers interested in using these techniques, including guidance on how to statistically control for the inherent similarities shared by related species: an important concern because simple, cross‐species comparisons that do not do this may well fail to meet statistical assumptions of non‐independence. The few relevant studies that have investigated captive wild animals’ welfare problems using this method are described. Overall, such approaches reap value from the great number and diversity of species held in captivity (e.g., the many thousands of species held in zoos); can yield new insights from existing data and published results; render previously intractable welfare questions (such as “do birds need to fly?” or “do Carnivora need to hunt?”) amenable to study; and generate evidence‐based principles for integrating animal welfare into collection planning.  相似文献   

3.
The health aspects and benefits of conception control as a justification for U.S. government support of family planning are reviewed. The Family Planning Services Act of 1970 set a goal of serving 5 million indigent women by 1975. It is predicted that the program will far surpass that goal. 340 million dollars were asked for contraceptive research by the federal government in fiscal year 1973, which is an example of the commitment to family planning by the government. Theoretical and sociopolitical reasons for family planning do not justify expenditure of public tax spending on population control assistance, but public health does justify those expenditures. Health and population control issues include the mental, physical, and social health of the parent and child, and broad demographic effects of age group population differentials, food supply, pollution, and health care services. The personal effects of an unwanted child are the most serious consequences of a lack of population control including economic and psychological hardship and damage. Maternal and infant mortality is related to age, economic status, and parity; e.g., toxemic pregnancy is more frequently found in young nulliparas. A correlation has been found between rapid parity and prematurity, though the research is not yet completely conclusive. Family planning through contraception and abortion can prevent unwanted pregnancies and unnecessary health risks from pregnancy by enabling parents to space and limit their families with safety. This is a highly desirable public health service goal and is emerging as a major concern of the federal government.  相似文献   

4.
Ticks are parasites of serious concern for humans, domesticated animals and wild animals. Despite scientific advances, in South America the principal control method for ticks is the use of chemical acaricides. Indiscriminate use of these products causes environmental pollution, food contamination and development of tick resistance to acaricides. In vitro studies and field trials have demonstrated that pathogenic fungal isolates not only cause mortality of many tick species, but also reduce subsequent generations due to effects on their reproductive efficacy. Accordingly, this review presents results of several studies which were conducted in South America. Furthermore, it outlines current information on fungal pathogens of ticks and discusses the need to develop and implement effective strategies for use of entomopathogenic fungi to control ticks in the near future.  相似文献   

5.
The issue of human reproductive cloning has recently received a great deal attention in public discourse. Bioethicists, policy makers, and the media have been quick to identify the key ethical issues involved in human reproductive cloning and to argue, almost unanimously, for an international ban on such attempts. Meanwhile, scientists have proceeded with extensive research agendas in the cloning of animals. Despite this research, there has been little public discussion of the ethical issues raised by animal cloning projects. Polling data show that the public is decidedly against the cloning of animals. To understand the public's reaction and fill the void of reasoned debate about the issue, we need to review the possible objections to animal cloning and assess the merits of the anti-animal cloning stance. Some objections to animal cloning (e.g., the impact of cloning on the population of unwanted animals) can be easily addressed, while others (e.g., the health of cloned animals) require more serious attention by the public and policy makers.  相似文献   

6.
Summary Australia’s temperate woodlands are environments of cultural and ecological importance and significant repositories of Australia’s biodiversity. Despite this, they have been heavily cleared, much remaining vegetation is in poor condition and many species of plants and animals are threatened. Here, we provide a brief overview of key issues relating to the ecology, management and policy directions for temperate woodlands, by identifying and discussing ten themes. When addressing issues relating to the conservation and management of temperate woodlands, spatial scale is very important, as are the needs for a temporal perspective and a complementary understanding of pattern and process. The extent of landscape change in many woodland environments means that woodland patches, linear networks and paddock trees are critical elements, and that there can be pervasive effects from ‘problem’ native species such as the Noisy Miner (Manorina melanocephala). These consequences of landscape change highlight the challenge to undertake active management and restoration as well as effective monitoring and long‐term data collection. In developing approaches for conservation and management of temperate woodlands, it is essential to move our thinking beyond reserves to woodland conservation and management on private land, and recognise the criticality of cross‐disciplinary linkages. We conclude by identifying some emerging issues in woodland conservation and management. These include the need to further develop non‐traditional approaches to conservation particularly off‐reserve management; the value of documenting approaches and programmes that demonstrably lead to effective change; new lessons that can be learned from intact examples of temperate woodlands; and the need to recognise how climate change and human population growth will interact with conservation and management of temperate woodlands in future decades.  相似文献   

7.
The concern about the preservation of biodiversity is due, in part, to a great level of media coverage granted in the last few years to global warming and consequential climatic changes. However, there are still considerably large gaps in scientific knowledge regarding the ecological status of many species, which results in an absence of conservation strategy for most of Earth’s biodiversity in need of it. The extinction of many animal and plant species can have catastrophic consequences on the ecosystems’ balance and also in human well-being, resultant from the break of ecological services. To exemplify how a specific group of microscopic animals can be endangered, I have analyzed the case of the phylum Tardigrada. Tardigrades are microscopic animals that inhabit most environments: terrestrial, freshwater and marine. Even though many species are widespread and the terrestrial ones granted with cryptobiotic skills, they are adapted to each habitat type and, additionally, to local environmental patterns. This means that these tiny metazoans can be under significant environmental pressure in the various habitat types they are found in. The potential need of protective and compensatory measures aiming for appropriate conservation of these life forms is discussed, as is the need of studying for their objective elaboration.  相似文献   

8.
There is an increasing demand for management of feral and wild carnivores; since many of them have become "pest species" by adapting successfully to changing environments, having substantial impacts on their prey species, and serving as reservoirs for infectious diseases. Also in captivity, a low adult mortality and an increase in longevity, especially in large carnivores, cause an urgent need for population management. This paper presents an overview on contraceptive strategies to control reproduction in carnivores. Factors that have to be considered before applying a certain method for fertility suppression are discussed. For birth control, several methods of hormonal chemosterilization, immunocontraception and pregnancy termination have been developed in domestic and captive exotic carnivores, but none of them are yet suitable for free-ranging animals. GnRH agonists, which suppress pituitary function very efficiently, are recommended in captive and domestic animals for reversible contraception. Immunological contraception, causing prolonged infertility after single application, is a promising approach for feral animals. However, a specific gamete or hormone-derived "self" antigen must be identified for each particular species.  相似文献   

9.
With billions of individuals and possibly hundreds of thousands of genera, invertebrates represent the largest number and greatest diversity of all animals used in research. Although the capacity for nociception is recognized in many invertebrate taxa, researchers and IACUC members are challenged by a lack of clear understanding of invertebrate welfare and by differing standards of moral concern for these taxa. In practice this has led IACUCs to consider invertebrates in two major groups: species worthy of increased moral concern approximating that shown to vertebrate species (this group includes cephalopods and to some extent decapod crustaceans) and all others. This dichotomy has led to differences in how invertebrate research is regulated and documented. This article presents two case studies illustrating specific concerns in invertebrate research protocols and then provides relevant information to address practical IACUC matters related to regulatory and ethical issues, sourcing and record keeping, risk management, assessment of pain and nociception in invertebrates, housing and husbandry, invasive procedures, veterinary care, and humane endpoints.  相似文献   

10.
Many bird species of lowland farmland have declined substantially in the United Kingdom over the past 30 years. Declines among farmland specialists are steeper than for generalists and were most rapid for these specialists in the 1970s and 1980s. These changes have been linked to increased agricultural intensification and are reflected in Red or Amber conservation concern status for many common farmland species, as well as for rarer ones. We review long- and short-term population trends and the conservation status of lowland farmland birds in the UK using the latest available information from bird surveys, and examine patterns among species. Analyses of demographic parameters suggest broadly that the key factor driving population changes of seed-eating and migrant birds is overwinter survival, whereas for many non-passerine species population growth appears to be limited by productivity. Population trends for a suite of lowland farmland species were first combined in the UK Government's headline wild bird indicator published in 1998. This 'Skylark index' as it is sometimes known was intended to reflect the health of the wider countryside and struck a chord with the public and decision-makers. We look at the behaviour of the composite indicator and explore the population dynamics of the increasing and declining species separately. Simple models of population growth in these groups are then used to explore plausible scenarios for delivering the Government's Public Service Agreement target to reverse the long-term decline in the number of farmland birds by 2020.  相似文献   

11.
A professional approach to conservation of biodiversity requires good knowledge, but we do not even know anywhere near how many species do occur on earth. We even know less on the conservation status of the living world. Factors threatening biodiversity are many and diverse. In addition to key problems such as human population growth, or ever increasing and unsustainable use of resources, effective biodiversity conservation is also hampered by massive lack of knowledge, a growing gap of trained taxonomists and ecologists, bureaucracy, politics and serious misinterpretation of important issues affecting biodiversity. In order to reduce the knowledge gap, the need to catalogue and conserve the diversity of live on earth must be seen as an important global challenge and must be funded with appropriate resources accordingly.  相似文献   

12.
Recent global warming and other anthropogenic changes have caused well‐documented range shifts and population declines in many species over a large spatial extent. Most large‐scale studies focus on birds, large mammals, and threatened species, whereas large‐scale population trends of small to medium‐sized mammals and species that are currently of least concern remain poorly studied. Large‐scale studies are needed because on a smaller scale, important patterns may be masked by local variation and stochastic processes. Here, we utilized snow track census data from Finland and NW Russia to estimate population growth rates of the Eurasian red squirrel Sciurus vulgaris for a period of 17 yr in an area of over 1 000 000 km2. We also studied the effects of changes in summer and winter temperatures, winter precipitation, predator abundance, and canopy cover on estimated red squirrel population growth rates. Our results suggest that red squirrel populations have declined in most parts of the study area, the only remarkable exception being SW Russia. These results are in concordance with previous studies suggesting that species that are still common and of least concern may be declining. However, our findings are in contrast to the common pattern of northern populations of boreal species increasing due to global warming. The estimated population growth rates are in synchrony over vast areas, suggesting that the underlying reasons also operate on a large scale. We indeed find that the population growth rate was lower in regions where winters warmed faster during the study period, suggesting that changes in the environment (or biotic changes associated with it) are linked with the decline of red squirrels.  相似文献   

13.
Internal and external parasites remain a significant concern in laboratory rodent facilities, and many research facilities harbor some parasitized animals. Before embarking on an examination of animals for parasites, two things should be considered. One: what use will be made of the information collected, and two: which test is the most appropriate. Knowing that animals are parasitized may be something that the facility accepts, but there is often a need to treat animals and then to determine the efficacy of treatment. Parasites may be detected in animals through various techniques, including samples taken from live or euthanized animals. Historically, the tests with the greatest diagnostic sensitivity required euthanasia of the animal, although PCR has allowed high-sensitivity testing for several types of parasite. This article demonstrates procedures for the detection of endo- and ectoparasites in mice and rats. The same procedures are applicable to other rodents, although the species of parasites found will differ.  相似文献   

14.
The native fauna of isolated island systems is generally unique with acute conservation issues. For spiders in Hawaii, the first impediment to effective conservation is lack of taxonomic knowledge. The primary conservation concerns are related to the highly localized areas of endemicity of many species, with associated small population sizes. Species on insular systems tend to occur naturally in small populations, and small population size itself may not be a cause for conservation concern. However, for spiders and other arthropods, which tend to have shorter generation times compared to vertebrates, population fluctuations will tend to be more frequent, rendering them more vulnerable to extinction through demographic accidents at small population size. The knowledge we have to date suggests that habitat disturbance and alien species invasion are probably the major factors affecting native spiders in the islands. For a given natural community, the ability of species to accommodate habitat perturbation may be related more to the novelty of the perturbation than to its apparent severity. Although native spiders appear to tolerate disruption of the species composition of the native vegetation, evidence suggests that they are severely impacted by alien arthropod predators, in particular social hymenoptera, a group not represented among native Hawaiian arthropods.  相似文献   

15.

Background

Climate change is affecting many physical and biological processes worldwide. Anticipating its effects at the level of populations and species is imperative, especially for organisms of conservation or management concern. Previous studies have focused on estimating future species distributions and extinction probabilities directly from current climatic conditions within their geographical ranges. However, relationships between climate and population parameters may be so complex that to make these high-level predictions we need first to understand the underlying biological processes driving population size, as well as their individual response to climatic alterations. Therefore, the objective of this study is to investigate the influence that climate change may have on species population dynamics through altering breeding season.

Methodology/Principal Findings

We used a mechanistic model based on drivers of rabbit reproductive physiology together with demographic simulations to show how future climate-driven changes in breeding season result in contrasting rabbit population trends across Europe. In the Iberian Peninsula, where rabbits are a native species of high ecological and economic value, breeding seasons will shorten and become more variable leading to population declines, higher extinction risk, and lower resilience to perturbations. Whereas towards north-eastern countries, rabbit numbers are expected to increase through longer and more stable reproductive periods, which augment the probability of new rabbit invasions in those areas.

Conclusions/Significance

Our study reveals the type of mechanisms through which climate will cause alterations at the species level and emphasizes the need to focus on them in order to better foresee large-scale complex population trends. This is especially important in species like the European rabbit whose future responses may aggravate even further its dual keystone/pest problematic. Moreover, this approach allows us to predict not only distribution shifts but also future population status and growth, and to identify the demographic parameters on which to focus to mitigate global change effects.  相似文献   

16.
In spite of the existence of a vast body of information on the plant diversity of the Amazon, there remain significant obstacles to informed decision-making and management for conservation. Species distributions are poorly understood and the relationships between diversity and composition of vegetation, ecosystem services and resilience to climatic fluctuations are insufficiently clear. The geographic distribution of phylogenetic diversity in relation to current protected areas is unexplored and very little is known about intraspecific genetic variability and its practical significance. Interpretation of vegetation differentiation and distribution remains relatively simplistic; there are still large parts of the basin for which few or no botanical data exist, and many rare and sparsely distributed species remain undiscovered. Improved understanding of the ecological roles, dynamics and associations of the species of greatest importance for the maintenance of sustainable livelihoods and ecosystem services, habitat restoration and adaptation to climate change is a high priority. In many cases these are common and widespread species. Some of these issues are explored by looking at the Cristalino region in northern Mato Grosso as a case-study. Effective integration, quality assessment, synthesis and application of existing data on the plant diversity of the Amazon will help to address these issues. However, more targeted information is needed from the ground. Future prioritisation of research effort will require a careful and pragmatic balance between the ‘traditional’ focus on rare and endemic species and species-rich communities, and the growing need to understand the key ‘framework’ elements that will determine the future of the Amazon environment. Similar situations are faced elsewhere in the tropics: for botanical research institutes in the 21st century this demands an urgent re-evaluation of core activities and concerted engagement with the issues and challenges facing conservation in a context of rampant population growth, climate change and environmental destruction.  相似文献   

17.
This paper presents the results of an investigation to determine perceptions, awareness, and knowledge of the unwanted horse population in Illinois from the viewpoint of horse owners, non-horse owners, and equine industry stakeholders. A questionnaire included items that pertained to knowledge of current legislation, equine background, current methods of controlling the unwanted horse population, and methods that respondents believe would reduce the unwanted horse population in Illinois. Results indicated that 58% of horse owners viewed horses as companion animals. Respondents perceived financial hardship to be the major reason why horses become unwanted. Current methods of managing unwanted horse populations were found to be ineffective. Reducing the costs of euthanasia and carcass disposal, allowing processing facilities to reopen in Illinois, and increasing the availability of gelding programs emerged as the most effective ways to manage the unwanted horse population. Results of this survey may lead to greater awareness of the unwanted horse population in Illinois. Furthermore, these results may lead to discussions about future legislation in the State designed to support and manage unwanted horses.  相似文献   

18.
The seasonally determined demographic structure of two semi-arid rodents, both agricultural pest species (the leaf-eared mouse (Phyllotis darwini) in Chile and the multimammate mouse (Mastomys natalensis) in Tanzania), is analysed using capture-mark-recapture (CMR) statistical models and measures for elasticity (the relative change in the growth rate due to a relative unit change in the parameter of concern) derived from projection linear matrix models. We demonstrate that reproduction and survival during the breeding season contribute approximately equally to population growth in the leaf-eared mouse, whereas the multimammate mouse is characterized by a more clearly defined seasonal structure into breeding and non-breeding seasons and that reproduction contributes far more than survival during the breeding season. On this basis, we discuss evolutionary and applied (pest control) issues. Regarding the evolution of life histories (leading to a maximization of the overall net annual growth rate), we suggest that for the leaf-eared mouse, features favouring survival throughout the year will provide selective value, but that during the main breeding season, features favouring reproduction and survival are about equally favourable. For the multimammate mouse, features favouring survival are particularly important outside the breeding season, whereas during the breeding season features favouring reproduction are more important. Regarding pest control (aiming at reducing the overall net annual growth rate), we suggest that (ignoring economic considerations) affecting survival outside the main breeding season is particularly effective for the leaf-eared mouse, a feature that is even more the case for the multimammate mouse. In sum, we demonstrate through this comparative study that much is to be learnt from studying the dynamics of fluctuating small rodents-a focal issue within much of population ecology.  相似文献   

19.
In reproduction, many animal species migrate to local habitats that are appropriate for reproduction and for growth of newly born offspring. The examples are ubiquitous among crabs, freshwater fishes, amphibians, migratory birds, and sea animals. We propose a basic equation for population dynamics of such animals, assuming that the number of offspring is proportional to the area of the local breeding habitats as a first approximation. This equation is very simple to be solved analytically, and useful for representing environmental issues of habitat destruction and degradation. According to the equation, the adult density in breeding habitats increases temporarily during habitat destruction and returns to the original density afterwards. The temporal peak value is higher for a larger proportion of area with destruction, a higher temporal rate of destruction, and a higher survival probability of the adults. In contrast, habitat degradation results simply in a decrease of the adult density in breeding habitats. Using this equation, we will discuss the vulnerability of populations to epidemic diseases due to temporal local high densities with decreasing breeding habitats by human activities, exemplifying an outbreak of cyprinid herpesvirus 3 for wild carps in Lake Biwa.  相似文献   

20.
Children are increasingly viewed as important recipients of educational interventions to improve animal welfare, yet research examining their perspectives is lacking, particularly within the UK. Helping children to care appropriately for animals depends, not least, on an ability to understand the needs of different species and correctly identify cues given by the animal that indicate its welfare state. This study began to explore: (a) children’s perceptions of welfare needs, focusing on four common pet animals; (b) influences on the development of knowledge; (c) beliefs about whether or not (all) animals are sentient, and (d) their confidence in identifying when their own pets are in need. Fourteen focus groups were carried out with 53 children aged 7 to 13 years. Findings highlighted an affirmative response that animals have feelings (dogs especially), albeit with doubts about this applying universally. There was wide variation in children’s knowledge of welfare needs, even among owners of the animal in question. Conversely, some children lacked confidence in spite of the extensive knowledge they had developed through direct experience. An important finding was a perceived difficulty in identifying the needs of particular species or specific types of need in their own pets. Fitting well with a recent emphasis on “positive welfare,” children felt that many animals need demonstrative love and attention, especially cats and dogs. While there is clearly scope for educating children about common needs and cues that indicate animals’ welfare state, other areas pose a greater challenge. Emotional connection seems important in the development of extensive knowledge and concern for welfare. Accordingly, animals that do not possess the kind of behavioral repertoire that is easy to interpret or allows for a perceived sense of reciprocity are possibly at risk of negative welfare experiences.  相似文献   

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