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1.
Despite complete legal protection, improvements in infrastructure, and market conditions that provide easier access to other protein sources, illegal poaching of sea turtles for consumption in Baja California Sur (BCS), Mexico remains a major threat to their recovery. Few studies have focused on understanding the economic and social drivers behind this activity, which is fundamental to determining best practices for discouraging it. From June 2007 to April 2008 we conducted eight in-depth, semi-structured interviews with sea turtle poachers at five coastal communities in BCS to determine the drivers influencing them. The most prevalent reasons for illegal poaching were direct economic benefits, lack of law enforcement and ease of escape from or bribery of authorities, and strong family tradition. Our results suggest that to reduce illegal poaching it will be necessary to better enforce existing environmental laws, reduce social acceptance of sea turtle hunting throughout the region, educate fishers on the ecological importance of sea turtles, and show fishers direct economic benefits from non-consumptive use of sea turtles, such as ecotourism.  相似文献   

2.
Anticoagulant rodenticide (AR) poisoning has emerged as a significant concern for conservation and management of non-target wildlife. The purpose for these toxicants is to suppress pest populations in agricultural or urban settings. The potential of direct and indirect exposures and illicit use of ARs on public and community forest lands have recently raised concern for fishers (Martes pennanti), a candidate for listing under the federal Endangered Species Act in the Pacific states. In an investigation of threats to fisher population persistence in the two isolated California populations, we investigate the magnitude of this previously undocumented threat to fishers, we tested 58 carcasses for the presence and quantification of ARs, conducted spatial analysis of exposed fishers in an effort to identify potential point sources of AR, and identified fishers that died directly due to AR poisoning. We found 46 of 58 (79%) fishers exposed to an AR with 96% of those individuals having been exposed to one or more second-generation AR compounds. No spatial clustering of AR exposure was detected and the spatial distribution of exposure suggests that AR contamination is widespread within the fisher's range in California, which encompasses mostly public forest and park lands Additionally, we diagnosed four fisher deaths, including a lactating female, that were directly attributed to AR toxicosis and documented the first neonatal or milk transfer of an AR to an altricial fisher kit. These ARs, which some are acutely toxic, pose both a direct mortality or fitness risk to fishers, and a significant indirect risk to these isolated populations. Future research should be directed towards investigating risks to prey populations fishers are dependent on, exposure in other rare forest carnivores, and potential AR point sources such as illegal marijuana cultivation in the range of fishers on California public lands.  相似文献   

3.
Understanding the role of disease in population regulation is important to the conservation of wildlife. We evaluated the prevalence of Toxoplasma gondii exposure and Sarcocystis spp. infection in 46 road-killed and accidentally trapper-killed fisher (Martes pennanti) carcasses collected and stored at -20 C by the Pennsylvania Game Commission from February 2002 to October 2008. Blood samples were assayed for T. gondii antibodies using the modified agglutination test (MAT, 1 : 25) and an indirect immunofluorescent antibody test (IFAT, 1 : 128). For genetic analysis, DNA samples were extracted from thoracic and pelvic limb skeletal muscle from each carcass to test for Sarcocystis spp. using 18s-rRNA PCR primers. Antibodies to T. gondii were found in 100% (38 of 38) of the fishers tested by MAT and in 71% (32 of 45) of the fishers tested by IFAT. PCR analysis revealed that 83% (38 of 46) of the fishers were positive for Sarcocystis spp. Sequence analysis of 7 randomly chosen amplicons revealed the fisher sarcocysts had a 98.3% to 99.1% identity to several avian Sarcocystis spp. sequences in GenBank. Data from our study suggest that a high percentage of fishers in Pennsylvania have been exposed to T. gondii and are infected with Sarcocystis spp.  相似文献   

4.
This article explores Arab American "invisibility" as a central theme in the historical narrative of Arab immigrants and their descendants in North America. "Invisibility" is primarily addressed in terms of Arab Americans' paradoxical positioning within the US racial/ethnic classification system. The article argues that four central paradoxes shape Arab American identity. The first paradox is that Arab Americans are a complex, diverse community, but are represented as a monolith in popular North American media images. The second paradox is that Arab Americans are simultaneously racialized as whites and as non-whites. The third paradox is that Arab Americans are racialized according to religion (Islam) rather than biology (phenotype). The fourth paradox involves the intersection between religious forms of identity that Arab immigrants bring to the US and racial forms of identity that structure US society. Overall, the article claims that each paradox of Arab American identity reinforces the difficulties associated in classifying this population.  相似文献   

5.
Wildlife populations of conservation concern are limited in distribution, population size and persistence by various factors, including mortality. The fisher (Pekania pennanti), a North American mid-sized carnivore whose range in the western Pacific United States has retracted considerably in the past century, was proposed for threatened status protection in late 2014 under the United States Endangered Species Act by the United States Fish and Wildlife Service in its West Coast Distinct Population Segment. We investigated mortality in 167 fishers from two genetically and geographically distinct sub-populations in California within this West Coast Distinct Population Segment using a combination of gross necropsy, histology, toxicology and molecular methods. Overall, predation (70%), natural disease (16%), toxicant poisoning (10%) and, less commonly, vehicular strike (2%) and other anthropogenic causes (2%) were causes of mortality observed. We documented both an increase in mortality to (57% increase) and exposure (6%) from pesticides in fishers in just the past three years, highlighting further that toxicants from marijuana cultivation still pose a threat. Additionally, exposure to multiple rodenticides significantly increased the likelihood of mortality from rodenticide poisoning. Poisoning was significantly more common in male than female fishers and was 7 times more likely than disease to kill males. Based on necropsy findings, suspected causes of mortality based on field evidence alone tended to underestimate the frequency of disease-related mortalities. This study is the first comprehensive investigation of mortality causes of fishers and provides essential information to assist in the conservation of this species.  相似文献   

6.
Ecology is a fundamental driving force for the evolutionary transition from solitary living to breeding cooperatively in groups. However, the fact that both benign and harsh, as well as stable and fluctuating, environments can favour the evolution of cooperative breeding behaviour constitutes a paradox of environmental quality and sociality. Here, we propose a new model – the dual benefits framework – for resolving this paradox. Our framework distinguishes between two categories of grouping benefits – resource defence benefits that derive from group‐defended critical resources and collective action benefits that result from social cooperation among group members – and uses insider–outsider conflict theory to simultaneously consider the interests of current group members (insiders) and potential joiners (outsiders) in determining optimal group size. We argue that the different grouping benefits realised from resource defence and collective action profoundly affect insider–outsider conflict resolution, resulting in predictable differences in the per capita productivity, stable group size, kin structure and stability of the social group. We also suggest that different types of environmental variation (spatial vs. temporal) select for societies that form because of the different grouping benefits, thus helping to resolve the paradox of why cooperative breeding evolves in such different types of environments.  相似文献   

7.
Modern social life is sometimes characterized as ‘post‐traditional’, an environment where personal identity is continually reconstructed. Concepts of ethnic identity on the other hand usually evoke some notion of tradition, continuity with the past, and intersubjectivity. This article discusses the personal accounts of Jewishness given by a sample of New Zealanders with ‘mixed’ (Jewish and gentile) backgrounds. It explores and analyses their use of themes that come from both modernity and Jewish tradition and defines the different types of identification implicit in their accounts. Particular attention is paid to how these kinds of identification are transmitted, because the literature (on both Jewishness and ethnicity in general) contains debates about the persistence of different expressions of identity. I conclude that a substantial dispersal of Jewish identity has occurred in New Zealand which apparently contradictory theoretical positions are useful in explaining. This suggests that a more holistic perspective is required to account adequately for the diversity of ethnic identity in contemporary society.  相似文献   

8.
The relationship between fishing, livelihood diversification and poverty was investigated in the lower Mekong basin, in Laos, where fishing forms an important, but usually secondary part of rural livelihoods. Results from a household survey show that participation in fishing is common and positively associated with higher occupational diversity and more agricultural activities. This is likely due to the low opportunity costs associated with many forms of fishing and factors such as tradition, enjoyment of fishing, underutilised labour and low capital requirements. Alternative livelihoods within the rural setting are therefore unlikely to cause fishers to leave the fishery, but instead strengthen the livelihood portfolio as a supplementary activity. Fishing is not an activity only for the very poorest households, but is undertaken by all wealth groups. However, fishing forms a greater proportion of income, employment and food security for the poor and is important in households with poor quality farm land.  相似文献   

9.
Phenotype, whether conventional or extended, is defined as a reflectionof an underlying genotype. Adaptation and the natural selection thatfollows from it depends upon a progressively harmonious fit betweenphenotype and environment. There is in Richard Dawkins' notion ofthe extended phenotype a paradox that seems to undercut conventionalviews of adaptation, natural selection and adaptation. In a nutshell, ifthe phenotype includes an organism's environment, how then can theorganism adapt to itself? The paradox is resolvable through aphysiological, as opposed to a genetic, theory of natural selection andadaptation.  相似文献   

10.
Understanding how fishers make decisions is important for improving management of fisheries. There is debate about the extent to which small-scale fishers follow an ideal free distribution (IFD) – distributing their fishing effort efficiently according to resource availability rather than being influenced by social factors or personal preference. Using detailed data from 1800 fisher catches and from semi-structured interviews with over 700 fishers at Lake Alaotra, the largest inland fishery in Madagascar, we show that fishers generally conform to IFD. However, there were differences in catch: effort relationships between fishers using different gear types as well as other revealing deviations from the predictions of IFD. Fishers report routine as the primary determinant of their choice of fishing location, explaining why they do not quickly respond to changes in catch at a site. Understanding the influences on fishers’ spatial behaviour will allow better estimates of costs of fishing policies on resource users, and help predict their likely responses. This can inform management strategies to minimise the negative impacts of interventions, increasing local support for and compliance with rules.  相似文献   

11.
This paper explores an ongoing dialogue about Christianity in light of the recent influx of HIV and AIDS into the villages of the Gogodala of Western Province, Papua New Guinea. I argue that a suggestion by a woman in late 2004 to ‘build a wall’ around the Gogodala region in Western Province in order to stop or slow the spread of HIV/AIDS reflects a recent concern with the sustainability of this rural Christian community, referred to in English as ‘Christian country’. Understanding AIDS to be a threat posed largely from outsiders, whether Papua New Guinean or European, sections of these primarily village‐based communities aim to create both a physical and metaphorical boundary between themselves and outsiders. At present, local prevention and intervention strategies concerning HIV and AIDS focus on conservative, evangelical narratives about the preservation of the principles and practices of Christian country, through the repudiation of unrestrained sexuality, for example, which is believed to be increasingly prevalent not only in their own area but throughout urban Papua New Guinea. A growing divide between rural and urban Gogodala, then, has become a major part of the local dialogue about AIDS and represents significant contestation over the practices and ideational basis of Christian country.  相似文献   

12.
Abstract

As one of the oldest Asian American groups in the USA, most Japanese Americans are of the third and fourth generations and have become well integrated in mainstream American society. However, they are still racialized as foreigners simply because of their Asian appearance. Their Asian phenotype continues to have a foreigner connotation because of large-scale immigration from Asia and an American national identity that is racially defined as white. This paper analyses how later-generation Japanese Americans are racialized as outsiders in their daily interaction with mainstream Americans, which is often accompanied by essentialized assumptions that they are also culturally foreign. In response, they engage in everyday struggles for racial citizenship by demanding inclusion in the national community as Americans despite their racial differences. It is uncertain whether such attempts to contest their racialization will cause current mono-racial notions of American identity to be reconsidered in more inclusive and multiracial ways.  相似文献   

13.
Spatial management tools, such as marine spatial planning and marine protected areas, are playing an increasingly important role in attempts to improve marine management and accommodate conflicting needs. Robust data are needed to inform decisions among different planning options, and early inclusion of stakeholder involvement is widely regarded as vital for success. One of the biggest stakeholder groups, and the most likely to be adversely impacted by spatial restrictions, is the fishing community. In order to take their priorities into account, planners need to understand spatial variation in their perceived value of the sea. Here a readily accessible, novel method for quantitatively mapping fishers’ spatial access priorities is presented. Spatial access priority mapping, or SAPM, uses only basic functions of standard spreadsheet and GIS software. Unlike the use of remote-sensing data, SAPM actively engages fishers in participatory mapping, documenting rather than inferring their priorities. By so doing, SAPM also facilitates the gathering of other useful data, such as local ecological knowledge. The method was tested and validated in Northern Ireland, where over 100 fishers participated in a semi-structured questionnaire and mapping exercise. The response rate was excellent, 97%, demonstrating fishers’ willingness to be involved. The resultant maps are easily accessible and instantly informative, providing a very clear visual indication of which areas are most important for the fishers. The maps also provide quantitative data, which can be used to analyse the relative impact of different management options on the fishing industry and can be incorporated into planning software, such as MARXAN, to ensure that conservation goals can be met at minimum negative impact to the industry. This research shows how spatial access priority mapping can facilitate the early engagement of fishers and the ready incorporation of their priorities into the decision-making process in a transparent, quantitative way.  相似文献   

14.
Parrondo's paradox, in which losing strategies can be combined to produce winning outcomes, has received much attention in mathematics and the physical sciences; a plethora of exciting applications has also been found in biology at an astounding pace. In this review paper, the authors examine a large range of recent developments of Parrondo's paradox in biology, across ecology and evolution, genetics, social and behavioral systems, cellular processes, and disease. Intriguing connections between numerous works are identified and analyzed, culminating in an emergent pattern of nested recurrent mechanics that appear to span the entire biological gamut, from the smallest of spatial and temporal scales to the largest—from the subcellular to the complete biosphere. In analyzing the macro perspective, the pivotal role that the paradox plays in the shaping of biological life becomes apparent, and its identity as a potential universal principle underlying biological diversity and persistence is uncovered. Directions for future research are also discussed in light of this new perspective.  相似文献   

15.
Overfishing threatens coral reefs worldwide, yet there is no reliable estimate on the number of reef fishers globally. We address this data gap by quantifying the number of reef fishers on a global scale, using two approaches - the first estimates reef fishers as a proportion of the total number of marine fishers in a country, based on the ratio of reef-related to total marine fish landed values. The second estimates reef fishers as a function of coral reef area, rural coastal population, and fishing pressure. In total, we find that there are 6 million reef fishers in 99 reef countries and territories worldwide, of which at least 25% are reef gleaners. Our estimates are an improvement over most existing fisher population statistics, which tend to omit accounting for gleaners and reef fishers. Our results suggest that slightly over a quarter of the world’s small-scale fishers fish on coral reefs, and half of all coral reef fishers are in Southeast Asia. Coral reefs evidently support the socio-economic well-being of numerous coastal communities. By quantifying the number of people who are employed as reef fishers, we provide decision-makers with an important input into planning for sustainable coral reef fisheries at the appropriate scale.  相似文献   

16.
Can the abundance of fish populations be effectively determined by the collection of scientific research with support from recreational fishers? Collecting and analysing fishing data from recreational fishers to aid management are not new; however, engaging fishers in a scientific survey design to produce specific population estimates is rarely undertaken. We engaged recreational fishers to assist with field sampling to provide an estimate Murray Crayfish (Euastacus armatus von Martens, 1866) abundance at three sites on the Edward River which were recently impacted by an extreme blackwater disturbance. Employing mark‐resight models, fishers undertook crayfish surveys and produced research data which estimated adult population sizes of Murray Crayfish in the studied reaches ranging between 94.27 ± 24.72 individuals (Below Stevens) and 450.01 ± 175.30 individuals (Twin Rivers). Both the effective undertaking of the mark‐resight designs in collaboration with fishers and acquiring population abundance estimates for Murray Crayfish in a river reach are concepts which have not previously been published and are important attributes for the management of aquatic species.  相似文献   

17.
This study examines the ways in which perceived socioeconomic threat, perceived threat to national identity, and prejudice (as reflected in negative stereotypes and desire for social distance) prompt objection to allocation of rights to out-groups. The paper presents a simultaneous test of three theoretical explanations and delineates the complex interrelationships among all concepts, using data from a representative sample of Israelis in structural equation models. This study finds that: (1) perception of socioeconomic threat is positively associated with perception of threat to national identity; (2) the two types of threat do not directly affect attitudes toward allocation of rights, but instead tend to increase negative stereotyping of the out-group; (3) negative stereotypes are likely to contribute to a desire for social distance from the out-group; and (4) the attribution of negative characteristics and a sense of social distance tend to increase objection to allocation of social rights to the out-group.  相似文献   

18.
Information on fish trophic levels is important to assess fishing impacts and to better understand the bioaccumulation of pollutants within aquatic food chains. The local ecological knowledge held by small-scale fishers can fill knowledge gaps in fish trophic ecology. We estimated the trophic levels of 69 tropical and subtropical fish species (33 coastal and 36 freshwater species) using data on fish diets from the literature and obtained from interviews with Brazilian fishers. The fish trophic levels estimated from fishers’ knowledge were positively correlated with the trophic levels estimated using data from biological studies for both coastal and freshwater fish. The fishers’ knowledge also indicated bioaccumulation patterns, as the fish trophic levels estimated from fishers’ knowledge were positively related to the mercury (Hg) content in fish muscle (wet weight, from literature data) in 41 fish species (15 coastal and 26 freshwater). These findings reveal the potential for new applications of fishers’ knowledge to ecotoxicology, which could improve management of aquatic ecosystems and strengthen fishers’ political status.  相似文献   

19.
Salinity as a determinant of salt lake fauna: a question of scale   总被引:25,自引:22,他引:3  
High and often variable salinity is an obvious feature of salt lakes. Correspondingly, salinity is usually assumed to be an important ecological determinant in such lakes. An investigation of the macroinvertebrate fauna of 79 lakes (salinities from 0.3 to 343 g 1–1) in the Western District of Victoria, Australia, examined this assumption. Over the total range of salinity, species richness and composition are highly correlated with salinity. However, these relationships become nonsignificant over intermediate ranges of salinity. Furthermore, many taxa have very broad tolerances to salinity at these intermediate ranges, implying that factors other than salinity may determine their distribution. An appreciation of scale (that is, the range of salinity over which observations are considered) resolves the paradox that, despite these broad tolerances by most taxa, species richness and composition strongly reflect salinity over the entire salinity range.  相似文献   

20.
The aboriginal populations of Peninsular Malaysia, also known as Orang Asli (OA), comprise three major groups; Semang, Senoi and Proto-Malays. Here, we analyzed for the first time KIR gene polymorphisms for 167 OA individuals, including those from four smallest OA subgroups (Che Wong, Orang Kanaq, Lanoh and Kensiu) using polymerase chain reaction-sequence specific primer (PCR-SSP) analyses. The observed distribution of KIR profiles of OA is heterogenous; Haplotype B is the most frequent in the Semang subgroups (especially Batek) while Haplotype A is the most common type in the Senoi. The Semang subgroups were clustered together with the Africans, Indians, Papuans and Australian Aborigines in a principal component analysis (PCA) plot and shared many common genotypes (AB6, BB71, BB73 and BB159) observed in these other populations. Given that these populations also display high frequencies of Haplotype B, it is interesting to speculate that Haplotype B may be generally more frequent in ancient populations. In contrast, the two Senoi subgroups, Che Wong and Semai are displaced toward Southeast Asian and African populations in the PCA scatter plot, respectively. Orang Kanaq, the smallest and the most endangered of all OA subgroups, has lost some degree of genetic variation, as shown by their relatively high frequency of the AB2 genotype (0.73) and a total absence of KIR2DL2 and KIR2DS2 genes. Orang Kanaq tradition that strictly prohibits intermarriage with outsiders seems to have posed a serious threat to their survival. This present survey is a demonstration of the value of KIR polymorphisms in elucidating genetic relationships among human populations.  相似文献   

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