952 resultados para MPAs, marine conservation, quotas, taxes, penalties, bonds, protected species


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The proposed Endangered Species Act listing of the gopher tortoise has the potential to impact the military mission at installations in the southeastern United States. Candidate Conservation Agreements with the U.S. Fish and Wildlife Service could be a tool to promote conservation and potentially preclude listing. This project identified military activities that could be affected and determined that military natural resources managers are unsure if such an agreement would prevent impacts to the military mission or impose the same restrictions as federal listing. This project found that if a gopher tortoise Candidate Conservation Agreement can be developed such that it benefits the species as well as the military, it should be used as a model for other species.

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The impact of sex-biased fishing and marine reserve protection on the mud crab Scylla serrata was examined by comparing the catch rates (catch-per-unit-effort, CPUE), mean size, sex ratios and movement of crabs in 2 coastal marine reserves (1.9 and 5.7 km(2)) and 4 fished non-reserve sites in subtropical Australia. Five years after closure, both marine reserves supported higher catch rates and a larger mean size of S. serrata than non-reserve sites. Males dominated catches of S. serrata in both marine reserves, where CPUE was at least twice as high within the reserves compared to non-reserve sites. Male crabs were also 10% larger in the reserves compared to adjacent fished areas, and of the total male catch, over 70% were equal to or greater than legal size compared to less than 50% outside the reserves. The sex ratio of S. serrata was skewed towards females in all nonreserve sites, which was most likely a result of the ban on taking female S. serrata in Moreton Bay. As only male crabs of >= 15 cm CW made up the S. serrata fishery in Moreton Bay, sex ratios of mature male and female crabs were examined, revealing a strong skew (2:1) towards mature males in both marine reserves. Of the 472 S. serrata captured in this study, 338 were tagged in the reserves in order to document movement of the crabs between the reserve and non-reserve sites. Of the 37 recaptured crabs, 73% were recorded inside the reserves, with some spillover (i.e. cross-boundary movement) of crabs recorded in fished areas. This study demonstrates the effectiveness of small (< 6 km(2)) marine reserves for sex-biased exploited fisheries species.

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Recent analyses assert that large marine vertebrates such as marine mammals are now 'functionally or entirely extinct in most coastal ecosystems'. Moreton Bay is a large diverse marine ecosystem bordering the fastest growing area in Australia. The human population is over 1.6 million and increasing yearly by between 10% and 13% with resultant impacts upon the adjoining marine environment. Nonetheless, significant populations of three species of marine mammals are resident within Moreton Bay and a further 14 species are seasonal or occasional visitors. This paper reviews the current and historical distributions and abundance of these species in the context of the current management regime and suggests initiatives to increase the resilience of marine mammal populations to the changes wrought by the burgeoning human population in coastal environments. (C) 2004 Elsevier Ltd. All rights reserved.

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A small, isolated population of the threatened western prairie fringed orchid (Platanthera praeclara Sheviak & Bowles) occurs at Pipestone National Monument, Minnesota, in a mesic prairie that is periodically burned to control invasive cool-season grasses. During 1995-2004, monitoring counts of flowering orchids in the monument varied considerably for different years. Similar precipitation amounts in the spring and histories of burning suggest that fire and precipitation in the spring were not the causes of the variation. For the eight non-burn years in the monitoring record, we compared the number of flowering plants and the precipitation amounts during six growth stages of the orchid and found a 2-variab1e model (precipitation during senescence/bud development and precipitation in the dormant period) explained 77% of the annual variation in number of flowering plants. We also conducted a fire experiment in early May 2002, the typical prescribed burn period for the monument, and found that the frequency of flowering, vegetative, and absent plants observed in July did not differ between burned and protected locations of orchids. We used the model and forecasts of precipitation in the spring to develop provisional burn decision scenarios. We discussed management implications of the scenarios.

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Most reef-building corals are known to engage in symbiosis not only with unicellular dinoflagellates from the genus, Symbiodinium, but they also sustain highly complex symbiotic associations with other microscopic organisms such as bacteria, fungi, and viruses. The details of these non-pathogenic interactions remain largely unclear. The impetus of this study is to gain a better understanding of the symbiotic interaction between marine bacteria and a variety of coral species representative of differing morphologies. Studies have shown that certain bacterial orders associate specifically with certain coral species, thus making the symbiotic synergy a non-random consortium. Consequently both corals and bacteria may be capable of emitting chemical cues that enables both parties to find one another and thus creating the symbiosis. One potential chemical cue could be the compound DMSP (Dimethylsulfoniopropionate) and its sulphur derivatives. Reef-building corals are believed to be the major producers of the DMSP and its derivatives during times of stress. As a result corals could potentially attract their bacterial consortium depending on their DMSP production. Corals may be able to adapt to fluctuating environmental conditions by changing their bacterial communities to that which may aid in survival. The cause of this attraction may stem from the capability of a variety of marine bacteria to catabolize DMSP into different metabolically significant pathways, which may be necessary for the survival of these mutualistic interactions. To test the hypothesis that coral-produced DMSP play a role in attracting symbiotic bacteria, this study utilized the advent of high-through sequencing paired with bacterial isolation techniques to properly characterize the microbial community in the stony coral Porites astreoides. We conducted DMSP swarming and chemotaxis assays to determine the response of these coral-associated bacterial isolates towards the DMSP compound at differing concentrations. Preliminary data from this study suggests that six out of the ten bacterial isolates are capable of conducting unidirectional motility; these six isolates are also capable of conducting swarming motility in the direction of an increasing DMSP concentration gradient. This would indicate that there is a form of positive chemotaxis on behalf of the bacteria towards the DMSP compound. By obtaining a better understanding of the dynamics that drive the associations between bacterial communities and corals, we can further aid in the protection and conservation processes for corals. Also this study would further elucidate the significance of the DMSP compound in the survival of corals under times of stress.

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Most reef-building corals are known to engage in symbiosis not only with unicellular dinoflagellates from the genus, Symbiodinium, but they also sustain highly complex symbiotic associations with other microscopic organisms such as bacteria, fungi, and viruses. The details of these non-pathogenic interactions remain largely unclear. The impetus of this study is to gain a better understanding of the symbiotic interaction between marine bacteria and a variety of coral species representative of differing morphologies. Studies have shown that certain bacterial orders associate specifically with certain coral species, thus making the symbiotic synergy a non-random consortium. Consequently both corals and bacteria may be capable of emitting chemical cues that enables both parties to find one another and thus creating the symbiosis. One potential chemical cue could be the compound DMSP (Dimethylsulfoniopropionate) and its sulphur derivatives. Reef-building corals are believed to be the major producers of the DMSP and its derivatives during times of stress. As a result corals could potentially attract their bacterial consortium depending on their DMSP production. Corals may be able to adapt to fluctuating environmental conditions by changing their bacterial communities to that which may aid in survival. The cause of this attraction may stem from the capability of a variety of marine bacteria to catabolize DMSP into different metabolically significant pathways, which may be necessary for the survival of these mutualistic interactions. To test the hypothesis that coral-produced DMSP play a role in attracting symbiotic bacteria, this study utilized the advent of high-through sequencing paired with bacterial isolation techniques to properly characterize the microbial community in the stony coral Porites astreoides. We conducted DMSP swarming and chemotaxis assays to determine the response of these coral-associated bacterial isolates towards the DMSP compound at differing concentrations. Preliminary data from this study suggests that six out of the ten bacterial isolates are capable of conducting unidirectional motility; these six isolates are also capable of conducting swarming motility in the direction of an increasing DMSP concentration gradient. This would indicate that there is a form of positive chemotaxis on behalf of the bacteria towards the DMSP compound. By obtaining a better understanding of the dynamics that drive the associations between bacterial communities and corals, we can further aid in the protection and conservation processes for corals. Also this study would further elucidate the significance of the DMSP compound in the survival of corals under times of stress.

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Social-ecological systems are often highly complex, making effective governance a considerable challenge. In large, heterogeneous systems, hierarchical institutional regimes may be efficient, but effective management outcomes are dependent on stakeholder support. This support is shaped by perceptions of legitimacy, which risks being undermined where resource users are not engaged in decision-making. Although legitimacy is demonstrably critical for effective governance, less is known about the factors contributing to stakeholders’ perceptions of legitimacy or how these perceptions are socially differentiated. We quantitatively assessed stakeholder perceptions of legitimacy (indicated by support for rules) and their contributory factors among 307 commercial fishers and tourism operators in Australia’s Great Barrier Reef Marine Park. Legitimacy was most strongly associated with trust in information from governing bodies, followed by confidence in institutional performance and the equity of management outcomes. Legitimacy differed both within and among resource user groups, which emphasizes the heterogeneous nature of commonly defined stakeholder groups. Overall, tourism operators perceived higher legitimacy than did commercial fishers, which was associated with higher trust in information from management agencies. For fishers, higher levels of trust were associated with: (1) engagement in fisheries that had high subsector cohesion and positive previous experiences of interactions with governing bodies; (2) location in areas with greater proximity to sources of knowledge, resources, and decision-making; and (3) engagement in a Reef Guardian program. These findings highlight the necessity of strategies and processes to build trust among all user groups in large social-ecological systems such as the Great Barrier Reef Marine Park. Furthermore, the social differentiation of perceptions that were observed within user groups underscores the importance of targeted strategies to engage groups that may not be heard through traditional governance channels.

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Density, species composition and antimicrobial resistance in bacteria of the Enterococcus genus were evaluated in seawater and sands from 2 marine recreational beaches with different levels of pollution. The 2 beaches showed predominance of Enterococcus faecalis and Enterococcus faecium, in the water and the sand. Dry sand presented higher densities of Enterococcus sp. and higher frequency of resistant strains than wet sand and seawater. The beach with a higher degree of pollution presented higher percentages of resistant strains (66.7% and 61.5%, in sand and in water, respectively) and resistance to a larger number of antimicrobials compared with the less polluted beach, Ilha Porchat (35.7% and 31.25% of resistant strains in sand and water, respectively). in water samples, the highest frequencies of resistance were obtained against streptomycin (38.5%) and erythromycin (25%), whilst in sand, the highest frequencies were observed in relation to erythromycin and tetracycline (38.1% and 14.3%, respectively). These results show that water and sands from beaches with high indexes of faecal contamination of human origin may be potential sources of contamination by pathogens and contribute to the dissemination of bacterial resistance. (C) 2007 Elsevier Ltd. All rights reserved.

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Benthic marine invertebrates may form metapopulations connected via propagule dispersal. Conservation efforts often target potential source coastlines to indirectly benefit areas depending on allochthonous offspring production. Besides population density, adult size structure, sex ratio, brooding frequency and the proportion of breeding individuals may significantly influence the reproductive output of benthic populations, but these effects have seldom been tested. We used rocky shore crabs to assess the spatial variability of such parameters at relevant scales for conservation purposes and to test their consistency over 2 consecutive years; we then used the data to address whether bottom-up processes or biological interactions might explain the patterns observed. We decomposed egg production rates into their components for the 2 most abundant brachyuran species inhabiting the intertidal rocky habitat. Adult density and brooding frequency varied consistently among shores for both species and largely explained the overall spatial trends of egg production. Temporally consistent patterns also included among-shore differences in the size of ovigerous females of the grapsid Pachygrapsus transversus and between-bay differences in the fecundity of the spider crab Epialtus brasiliensis. Sex ratio was remarkably constant in both. We found no positive or negative correlations between adult density and brooding frequency to support either the existence of a component Allee effect (lack of mate encounters) or an effect of intra-specific competition. Likewise, shore-specific potential growth in P. transversus does not negatively correlate with frequency of ovigerous individuals, as would be expected under a critical balance between these 2 processes. The patterns observed suggest that bottom-up drivers may best explain spatial trends in the reproductive output of these species.

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The potential for conservation of individual species has been greatly advanced by the International Union for Conservation of Nature's (IUCN) development of objective, repeatable, and transparent criteria for assessing extinction risk that explicitly separate risk assessment from priority setting. At the IV World Conservation Congress in 2008, the process began to develop and implement comparable global standards for ecosystems. A working group established by the IUCN has begun formulating a system of quantitative categories and criteria, analogous to those used for species, for assigning levels of threat to ecosystems at local, regional, and global levels. A final system will require definitions of ecosystems; quantification of ecosystem status; identification of the stages of degradation and loss of ecosystems; proxy measures of risk (criteria); classification thresholds for these criteria; and standardized methods for performing assessments. The system will need to reflect the degree and rate of change in an ecosystem's extent, composition, structure, and function, and have its conceptual roots in ecological theory and empirical research. On the basis of these requirements and the hypothesis that ecosystem risk is a function of the risk of its component species, we propose a set of four criteria: recent declines in distribution or ecological function, historical total loss in distribution or ecological function, small distribution combined with decline, or very small distribution. Most work has focused on terrestrial ecosystems, but comparable thresholds and criteria for freshwater and marine ecosystems are also needed. These are the first steps in an international consultation process that will lead to a unified proposal to be presented at the next World Conservation Congress in 2012.

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Conservation Letters published by Wiley Periodicals, Inc. Ecological degradation is accelerating, reducing our ability to detect and reverse declines. Resource user accounts have the potential to provide critical information on past change but their reliability can rarely be tested, hence they are often perceived as less valid than other forms of scientific data. We compared individual fishers' catch records, recorded 1-50 years ago, with their memories of past good, typical and poor catches for the corresponding time period. Good and poor catches were recalled with reasonable accuracy, matching variability in recorded catch with no significant change observed over time. Typical recalled catches were overestimated and became significantly more exaggerated over time, but were more comparable to mean than median recorded values. While accuracy of resource users' memory varied with the type of information recalled, our results suggest that carefully structured interview questions can produce reliable quantitative data to inform resource management, even after several decades have elapsed.

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Umbrella species are rarely selected systematically from a range of candidate species. On sandy beaches, birds that nest on the upper beach or in dunes are threatened globally and hence are prime candidates for conservation intervention and putative umbrella species status. Here we use a maximum-likelihood, multi-species distribution modeling approach to select an appropriate conservation umbrella from a group of candidate species occupying similar habitats. We identify overlap in spatial extent and niche characteristics among four beach-nesting bird species of conservation concern, American oystercatchers (Haematopus palliatus), black skimmers (Rynchops niger), least terns (Sterna antillarum) and piping plovers (Charadrius melodus), across their entire breeding range in New Jersey, USA. We quantify the benefit and efficiency of using each species as a candidate umbrella on the remaining group. Piping plover nesting habitat encompassed 86% of the least tern habitat but only 15% and 13% of the black skimmer and American oystercatcher habitat, respectively. However, plovers co-occur with all three species across 66% of their total nesting habitat extent (~ 649 ha), suggesting their value as an umbrella at the local scale. American oystercatcher nesting habitat covers 100%, 99% and 47% of piping plover, least tern and black skimmer habitat, making this species more appropriate conservation umbrellas at a regional scale. Our results demonstrate that the choice of umbrella species requires explicit consideration of spatial scale and an understanding of the habitat attributes that an umbrella species represents and to which extent it encompasses other species of conservation interest. Notwithstanding the attractiveness of the umbrella species concept, local conservation interventions especially for breeding individuals in small populations may still be needed.

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Conservation of free-ranging cheetah (Acinonyx jubatus) populations is multi faceted and needs to be addressed from an ecological, biological and management perspective. There is a wealth of published research, each focusing on a particular aspect of cheetah conservation. Identifying the most important factors, making sense of various (and sometimes contrasting) findings, and taking decisions when little or no empirical data is available, are everyday challenges facing conservationists. Bayesian networks (BN) provide a statistical modeling framework that enables analysis and integration of information addressing different aspects of conservation. There has been an increased interest in the use of BNs to model conservation issues, however the development of more sophisticated BNs, utilizing object-oriented (OO) features, is still at the frontier of ecological research. We describe an integrated, parallel modeling process followed during a BN modeling workshop held in Namibia to combine expert knowledge and data about free-ranging cheetahs. The aim of the workshop was to obtain a more comprehensive view of the current viability of the free-ranging cheetah population in Namibia, and to predict the effect different scenarios may have on the future viability of this free-ranging cheetah population. Furthermore, a complementary aim was to identify influential parameters of the model to more effectively target those parameters having the greatest impact on population viability. The BN was developed by aggregating diverse perspectives from local and independent scientists, agents from the national ministry, conservation agency members and local fieldworkers. This integrated BN approach facilitates OO modeling in a multi-expert context which lends itself to a series of integrated, yet independent, subnetworks describing different scientific and management components. We created three subnetworks in parallel: a biological, ecological and human factors network, which were then combined to create a complete representation of free-ranging cheetah population viability. Such OOBNs have widespread relevance to the effective and targeted conservation management of vulnerable and endangered species.

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Successful biodiversity conservation requires safeguarding viable populations of species. To work with this challenge Sweden has introduced a concept of Action Plans, which focus on the recovery of one or more species; while keeping in mind the philosophy of addressing ecosystems in a more comprehensive way, following the umbrella concept. In this paper we investigate the implementationprocess of the ActionPlanfor one umbrella species, the White-backed Woodpecker (WBW) Dendrocopos leucotos. We describe the plan's organisation and goals, and investigate its implementation and accomplishment of particular targets, based on interviewing and surveying the key actors. The achievement of the targets in 2005-2008 was on average much lower than planned, explained partially by the lack of knowledge/data, experienced workers, and administrative flexibility. Surprisingly, the perceived importance of particular conservation measures, the investment priority accorded to them, the money available and various practical obstacles all failed to kg? explain the target levels achieved. However qualitative data from both the interviews and the survey highlight possible implementation obstacles: competing interests with other conservation actions and the level of engagement of particular implementing actors. Therefore we suggest that for successful implementation of recovery plans, there is aneed for initial and inclusive scoping prior to embarking on the plan, where not only issues like ecological knowledge and practical resources are considered, but also possible conflicts and synergies with other conservation actions. An adaptive approach with regular review of the conservation process is essential, particularly in the case of such complex action plans as the one for the WBW.