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1.
Ecol Lett ; 25(9): 2062-2075, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35870157

RESUMEN

Identifying efficient biodiversity indicators is a key pillar of the global conservation strategy. Top predators have been proposed as reliable biodiversity signposts, but their role is controversial. Here, we verified their performance by a meta-analysis of published studies and found solid support for their efficacy as biodiversity indicators. As to be expected for any indicator species, efficacy was stronger for biodiversity components 'ecologically closer' to the predator (i.e. broad groups that include species providing key resources, such as avian and tree diversity for a bird-eating predator that nests in trees) and declined for the diversity of components more 'ecologically remote' from the predator (e.g. butterfly diversity for a fish-eating predator). This confirmed a link between the top predatory role and biodiversity and set the context for its functionality. These results show that, on average, top predators are justified candidates as biodiversity indicators and that prioritisation of conservation action based on their occurrence is likely to provide broader ecosystem benefits. However, such role should be confirmed on a case-by-case basis, acknowledging that no indicator can portray everything, checking the compatibility of the biodiversity components linked to the predator with the established conservation objectives and ideally integrating predators with other complementary indicator groups.


Asunto(s)
Ecosistema , Cadena Alimentaria , Animales , Biodiversidad , Aves , Conducta Predatoria , Árboles
2.
Ecotoxicol Environ Saf ; 208: 111676, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33396008

RESUMEN

The environmental risk assessment (ERA) for genetically modified plants (GMPs) is a prerequisite for commercial approval of these new varieties according to regulatory systems worldwide. The first country to regulate GM crops was the USA and the issue of possible environmental impacts was based on the principles used in risk assessment of pesticides. Two main pillars of this approach are the use of surrogate species for testing effects on non-target organisms using a tiered assessment with clear thresholds to indicate the need to move between tiers. The latest EFSA guidance document on ERA of Genetically Modified Organisms considers specifically the receiving environment in preparation of ERA for commercial cultivation of GMPs. According to existing guidelines in the EU, the receiving environment is defined by three mutually interacting components: the characteristics of the environmental stressor (i.e. the GM plant), the bio-geographical regions where the commercial release of the crop is expected and the agricultural systems therein. Difference in agronomic and ecological conditions (e.g. use of different varieties, vegetation of adjacent areas, non-target species assemblages, sensitivity of local species to the stressors) suggests that explicit considerations of the receiving environments are necessary. Results from field experiments indicate that differences in cultivation practices, e.g. the herbicide regime used on herbicide-tolerant GM crops, may induce direct and indirect effects on wild plant distribution and abundance, with consequent repercussions on food webs based on these plants. Moreover, ecological literature indicates that the concept of surrogate species has clear limitations if applied broadly to any ERA. Starting from case studies regarding GMPs, this paper discusses some ecological and agronomic characteristics of agro-ecosystems, which have implications in the elaboration of both hazard and exposure analyses during ERA. The species selection approach indicated in the EFSA Guidance Document and the consideration of the area(s) of the expected release of the new variety may provide the basis to an ecologically sound ERA for a range of environmental stressors. The quality of the data that become available for risk managers with this approach may support a more transparent and dependable ERA and risk management for GMPs as well as for other potential environmental stressors in agro-ecosystems.


Asunto(s)
Productos Agrícolas/crecimiento & desarrollo , Monitoreo del Ambiente/métodos , Inocuidad de los Alimentos/métodos , Plantas Modificadas Genéticamente/crecimiento & desarrollo , Productos Agrícolas/genética , Ecosistema , Monitoreo del Ambiente/legislación & jurisprudencia , Publicaciones Gubernamentales como Asunto , Guías como Asunto , Plaguicidas/toxicidad , Medición de Riesgo/métodos
3.
Zoo Biol ; 40(1): 65-75, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33043534

RESUMEN

The vast number of species threatened with extinction, coupled with the limited resources to support them, results in the need to prioritize species for conservation action. Similarly, zoo collection managers must prioritize species for inclusion at their institutions, which are also limited by space and resources. While conservation status is one factor considered by zoos, weight is also given to qualitative features and practical considerations when evaluating the fit of different species. Resultantly, the species prioritized by zoos have limited overlap with those prioritized for conservation. Several recent studies have highlighted that the majority of species maintained in zoos are ranked globally as least concern. Given the centrality of conservation to the modern mission of zoos, there is value in identifying clear connections between non-threatened species in zoos and the roles they can play in conservation. Surrogate species approaches have been used in many instances to facilitate indirect conservation, and several distinctive types of surrogacy have been formally described. The aim of this study is to define a novel form of species surrogacy (i.e., "proxy species") that draws utility from non-threatened species maintained in zoos. A proxy species is here defined as a non-threatened species managed ex situ that can be used as a flagship for a related threatened species that is morphologically similar but not otherwise represented in zoos. The benefits of this approach and opportunities for its application are here reviewed. This concept will provide opportunities to enhance the value of pre-existing zoo collections, and ultimately, support conservation objectives.


Asunto(s)
Animales de Zoológico , Conservación de los Recursos Naturales/métodos , Especies en Peligro de Extinción , Animales
4.
Conserv Biol ; 34(1): 158-167, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31069848

RESUMEN

Flagship species have been used widely as umbrella species (i.e., species with large home range whose protection often provides protection for sympatric species) in the management of China's nature reserves. This conflation of flagship and umbrella species is best represented by the giant panda (Ailuropoda melanoleuca) and other large, endangered mammals designated as conservation targets in site selection and planning of reserves. Few empirical studies have tested the effectiveness of flagship species as surrogates for a broader range of sympatric species. Using extensive camera-trap data, we examined the effectiveness of management zones designated to protect flagship (target) species in conserving sympatric species in 4 wildlife reserves (Gutianshan, Changqing, Laohegou, and Wolong). We tested whether the progression from peripheral to core zones was associated with an increasing habitat association for both target and sympatric species. The distribution patterns of the study species across the zones in each reserve indicated a disparity between management zones and the species' habitat requirements. Management zone was included in the final model for all target species, and most of them had higher occurrence in core zones relative to less-protected zones, but zone was not a predictor for most of the sympatric species. When management zone was associated with the occurrence of sympatric species, threatened species generally had higher detections in core zones, whereas common species had higher detections outside of the core zone. Our results suggested that reserve planning based on flagship species does not adequately protect sympatric species due to their specialized habitat requirements. We recommend re-examining the effectiveness of management zoning and urge a multispecies and reserve-wide monitoring plan to improve protection of China's wildlife.


Efectividad del Manejo de Zonación Diseñada para Especies Bandera en la Protección de Especies Simpátricas Resumen Las especies bandera se han utilizado ampliamente como especies paraguas (es decir, especies con una extensa distribución cuya protección frecuentemente proporciona protección para especies simpátricas) en el manejo de las reservas naturales de China. Esta combinación de especie bandera y especie paraguas tiene su mejor representación en el panda gigante (Ailuropoda melanoleuca) y otros grandes mamíferos en peligro de extinción designados como objetivos de conservación en la selección de sitio y la planeación de reservas. Pocos estudios empíricos han probado la efectividad de las especies bandera como sustitutas de una especie simpátrica con una distribución más amplia. Con datos numerosos de cámaras trampa, examinamos la efectividad de las zonas de manejo designadas para proteger a las especies bandera (objetivo) en la conservación de especies simpátricas dentro de cuatro reservas de fauna (Gutianshan, Changqing, Laohegou y Wolong). Probamos si la progresión de las zonas periféricas hacia las zonas núcleo estaba relacionada con asociaciones crecientes de hábitat tanto para las especies objetivo como para las simpátricas. Los patrones de distribución del estudio de especies a lo largo de las zonas en cada reserva indicaron una disparidad entre las zonas de manejo y los requerimientos de hábitat de las especies. La zona de manejo se incluyó dentro del modelo final para todas las especies objetivo y la mayoría de ellas tuvo una presencia más alta en las zonas núcleo en relación con las zonas de menor protección. Cuando la zona de manejo se asoció a la presencia de especies simpátricas, las especies amenazadas generalmente tuvieron un mayor número de detecciones en la zona núcleo, mientras que las especies comunes tuvieron un número más elevado de detecciones fuera de la zona núcleo. Nuestros resultados sugieren que la planeación de reservas basada en las especies bandera no protege adecuadamente a las especies simpátricas debido a sus requerimientos especializados de hábitat. Recomendamos una reexaminación de la efectividad del manejo de zonación y urgimos que se genere un plan de monitoreo multiespecífico en toda la reserva para mejorar la protección de la fauna en China.


Asunto(s)
Conservación de los Recursos Naturales , Simpatría , Animales , China , Ecosistema , Especies en Peligro de Extinción
5.
Ecol Appl ; 29(3): e01865, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30860659

RESUMEN

Surrogate species are commonly used in conservation science due to the fact that it is not feasible to measure and manage each component of biodiversity independently; yet, there is much debate about their efficacy. We use long-term monitoring data from six national park units in northern California and southern Oregon to test the focal species approach, wherein a suite of species is selected whose habitat requirements collectively encompass those of co-occurring species. Specifically, we examine how well existing Partners in Flight (PIF) habitat-based focal species lists and empirically derived focal species lists represent vegetation and three avian assemblages of interest: the entire assemblage, species of concern, and common species in steep decline. Existing PIF focal species lists were significantly correlated with the three alternative matrices of avian assemblages and vegetation, but not all parks and alternate matrices performed with equal correlative strength and/or significance. For example, existing PIF focal species lists were significantly correlated to the entire assemblage at five of the six parks and had ecologically meaningful correlations (>0.70) at four. However, PIF focal species list correlations with park specific species of concern and common species in steep declined varied widely, with correlations between 0.040-0.943 and 0.210-0.556, respectively. Averaged across park units the empirical focal species lists developed to represent both vegetation metrics and species of concern improved correlation with all alternative matrices of avian assemblages and vegetation metrics. We found that the focal species approach generally represented the entire avian community, but did not adequately represent suites of species of concern or common species in decline. Empirical testing is a critical step in validating or refining suites of focal species at management relevant scales, and in some instances, a more refined focal species list may increase overall utility of the surrogate species approach.


Asunto(s)
Aves , Bosques , Animales , Biodiversidad , California , Ecosistema , Oregon
6.
Ecotoxicology ; 28(1): 62-68, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30594985

RESUMEN

The use of indicator species to test for environmental stability and functioning is a widespread practice. In aquatic systems, several daphniids (Cladocera: Daphniidae) are commonly used as indicator species; registration of new pesticides are mandated by the Environmental Protection Agency to be accompanied by daphniid toxicity data. This reliance upon a few species to infer ecosystem health and function assumes similar responses to toxicants across species with potentially very different life histories and susceptibility. Incorporating lab-derived life-history data into a simple mathematical model, we explore the reliability of three different daphniid species as surrogates for each other by comparing their responses to reductions in survivorship and fecundity after simulated exposure to toxicants. Our results demonstrate that daphniid species' responses to toxicant exposure render them poor surrogates for one another, highlighting that caution should be exercised in using a surrogate approach to the use of indicator species in risk assessment.


Asunto(s)
Cladóceros/efectos de los fármacos , Fertilidad/efectos de los fármacos , Longevidad/efectos de los fármacos , Pruebas de Toxicidad , Animales , Rasgos de la Historia de Vida , Modelos Biológicos , Especificidad de la Especie
7.
Theor Popul Biol ; 119: 15-25, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29195772

RESUMEN

Prolonged exposure to a disturbance such as a toxicant has the potential to result in rapid evolution to toxicant resistance in many short-lived species such as daphniids. This evolution may allow a population to persist at higher levels of the toxicant than is possible without evolution. Here we apply evolutionary game theory to a Leslie matrix model for a daphniid population to obtain a Darwinian model that couples population dynamics with the dynamics of an evolving trait. We use the Darwinian model to consider how the evolution of resistance to the lethal or sublethal effects of a disturbance may change the population dynamics. In particular, we determine the conditions under which a daphniid population can persist by evolving toxicant resistance. We then consider the implications of this evolution in terms of the use of daphniids as surrogate species. We show for three species of daphniids that evolution of toxicant resistance means that one species may persist while another does not. These results suggest that toxicant studies that do not consider the potential of a species (or its surrogate) to develop toxicant resistance may not accurately predict the long term persistence of the species.


Asunto(s)
Evolución Biológica , Daphnia/efectos de los fármacos , Animales , Modelos Biológicos , Dinámica Poblacional
8.
Ecotoxicology ; 27(7): 819-833, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29492806

RESUMEN

Amphibians and reptiles are the two most endangered groups of vertebrates. Environmental pollution by pesticides is recognised as one of the major factors threatening populations of these groups. However, the effects of pesticides on amphibians and reptiles have been studied for few substances, which is partly related to the fact that these animals are not included in the mandatory toxicity testing conducted as part of environmental risk assessments of pesticides. Whether risks of pesticides to amphibians and reptiles are addressed by surrogate taxa used in risk assessment is currently under debate. In order to develop a scientifically sound and robust risk assessment scheme, information needs to be gathered to examine whether fish, birds and mammals are valid surrogates for amphibians and reptiles. We updated a systematic review of scientific literature that was recently published compiling toxicity data on amphibians and reptiles. The outcome of this review was analysed with the purposes to (1) compare endpoints from amphibians and reptiles with the available information from fish, birds and mammals, and (2) develop species sensitivity distributions (SSDs) for those substances tested in at least six amphibian species (no substances were found tested in at least six reptile species) to identify a candidate amphibian model species to be used as surrogate in risk assessment. A positive correlation was found between toxicity recorded on fish and amphibians, the former revealing, in general, to be more sensitive than the latter to waterborne pollutants. In the terrestrial environment, although birds and mammals were more sensitive than amphibians and reptiles to at least 60% of tested substances, just a few weak significant correlations were observed. As a general rule, homoeothermic vertebrates are not good surrogates for reptiles and terrestrial amphibians in pesticide risk assessment. However, some chemical-dependent trends were detected, with pyrethroids and organochlorine insecticides being more toxic to amphibians or reptiles than to birds or mammals. These trends could ultimately help in decisions about protection provided by surrogate taxa for specific groups of substances, and also to determine when risk assessment of pesticides needs to pay special consideration to amphibians and reptiles. The outcome of this review reflects that there is still much information needed to reduce uncertainties and extract relevant conclusions on the overall protection of amphibians and reptiles by surrogate vertebrates.


Asunto(s)
Aves , Peces , Mamíferos , Plaguicidas/toxicidad , Medición de Riesgo/métodos , Pruebas de Toxicidad , Anfibios , Animales , Reptiles
9.
J Wildl Manage ; 82(5): 948-957, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37799270

RESUMEN

The umbrella species concept, wherein multiple species are indirectly protected under the umbrella of a reserve created for one, is intended to enhance conservation efficiency. Although appealing in theory and common in practice, empirical tests of the concept have been scarce. We used a real-world, semi-protected reserve established to protect a high-profile umbrella species (greater sage-grouse [Centrocercus urophasianus]) to investigate 2 potential mechanisms underlying the concept's successful application: reserve size and species similarity. We estimated how much habitat protection the established reserve provided to 52 species of conservation concern associated with vegetation communities where greater sage-grouse occur. To illustrate the importance of reserve size, we compared the effectiveness of the established reserve to alternative greater sage-grouse reserves of various sizes and to simulated reserves of equal size but sited with no regard for greater sage-grouse. We further assessed whether key species' traits were associated with different levels of protection under the umbrella reserve. The established umbrella reserve protected 82% of the state's greater sage-grouse population and 0-63% of the habitat of the background species examined. The reserve outperformed equally sized, simulated reserves for only 12 of 52 background species. As expected, larger alternative reserves served as better umbrellas, but regardless of reserve size, not all species received equal protection. The established reserve was most effective at protecting the habitat of species that were most similar to the umbrella species (i.e., avian species, those highly associated with sagebrush plant communities, and those with widespread habitat). In contrast, the habitat of species with restricted distributions, particularly when combined with vegetation associations not closely matching the umbrella species, was not protected as well by the umbrella reserve. Such species require additional, targeted attention to achieve conservation objectives. Successful application of the umbrella species concept requires careful consideration of the characteristics of the umbrella species, the reserve delineated on its behalf, and the similarity of the umbrella species to its purported background species.

10.
Environ Manage ; 61(3): 398-407, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-28255729

RESUMEN

Environmental water managers must make best use of allocations, and adaptive management is one means of improving effectiveness of environmental water delivery. Adaptive management relies on generation of new knowledge from monitoring and evaluation, but it is often difficult to make clear inferences from available monitoring data. Alternative approaches to assessment of flow benefits may offer an improved pathway to adaptive management. We developed Bayesian statistical models to inform adaptive management of the threatened Australian grayling (Prototroctes maraena) in the coastal Thomson River, South-East Victoria Australia. The models assessed the importance of flows in spring and early summer (migration flows) for upstream dispersal and colonization of juveniles of this diadromous species. However, Australian grayling young-of-year were recorded in low numbers, and models provided no indication of the benefit of migration flows. To overcome this limitation, we applied the same models to young-of-year of a surrogate species (tupong-Pseudaphritis urvilli)-a more common diadromous species expected to respond to flow similarly to Australian grayling-and found strong positive responses to migration flows. Our results suggest two complementary approaches to supporting adaptive management of Australian grayling. First, refine monitoring approaches to allow direct measurement of effects of migration flows, a process currently under way. Second, while waiting for improved data, further investigate the use of tupong as a surrogate species. More generally, alternative approaches to assessment can improve knowledge to inform adaptive management, and this can occur while monitoring is being revised to directly target environmental responses of interest.


Asunto(s)
Teorema de Bayes , Conservación de los Recursos Hídricos , Monitoreo del Ambiente/métodos , Ríos , Salmonidae , Movimientos del Agua , Animales , Estaciones del Año , Victoria
11.
Plant Biotechnol J ; 15(10): 1340-1345, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28278353

RESUMEN

Bt rice can control yield losses caused by lepidopteran pests but may also harm nontarget species and reduce important ecosystem services. A comprehensive data set on herbivores, natural enemies, and their interactions in Chinese rice fields was compiled. This together with an analysis of the Cry protein content in arthropods collected from Bt rice in China indicated which nontarget species are most exposed to the insecticidal protein and should be the focus of regulatory risk assessment.


Asunto(s)
Proteínas Bacterianas/análisis , Endotoxinas/análisis , Cadena Alimentaria , Proteínas Hemolisinas/análisis , Insectos/química , Oryza/química , Animales , Toxinas de Bacillus thuringiensis , Herbivoria , Medición de Riesgo
12.
Parasitology ; 144(5): 629-640, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-27938437

RESUMEN

The population growth of endangered whooping cranes (Grus americana) is not consistent with species recovery goals, and the impact of parasite infection on whooping crane populations is largely unknown. Disease ecology and epidemiology research of endangered species is often hindered by limited ability to conduct invasive sampling on the target taxa. Accordingly, we hypothesized that sandhill cranes (Grus canadensis) would be a useful surrogate species to investigate the health impacts of Haemosporida infection in whooping cranes. Our goal was to compare the prevalence and diversity of Haemosporida infection between whooping cranes and sandhill cranes. We detected an overall infection prevalence of 83·6% (n = 61) in whooping cranes and 59·6% (n = 47) and 63·6 (n = 22) in two sympatric sandhill crane populations captured in Texas. Prevalence was significantly lower in allopatric sandhill cranes captured in New Mexico (12·1%, n = 33). Haemoproteus antigonis was the most abundant haemoparasite in cranes, present in 57·4% of whooping cranes and 39·2% of sandhill cranes; Plasmodium and Leucocytozoon were present at significantly lower levels. The high prevalence of Haemosporida in whooping cranes and sympatric sandhill cranes, with shared parasite lineages between the two species, supports sandhill cranes as a surrogate species for understanding health threats to endangered whooping cranes.


Asunto(s)
Enfermedades de las Aves/epidemiología , Haemosporida/aislamiento & purificación , Infecciones Protozoarias en Animales/epidemiología , Animales , Enfermedades de las Aves/parasitología , Aves , Especies en Peligro de Extinción , Femenino , Geografía , Haemosporida/genética , Masculino , New Mexico/epidemiología , Filogenia , Prevalencia , Infecciones Protozoarias en Animales/parasitología , Simpatría , Texas/epidemiología
13.
Mol Ecol ; 25(17): 4407-19, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27474399

RESUMEN

Plant diversity surely determines arthropod diversity, but only moderate correlations between arthropod and plant species richness had been observed until Basset et al. (Science, 338, 2012 and 1481) finally undertook an unprecedentedly comprehensive sampling of a tropical forest and demonstrated that plant species richness could indeed accurately predict arthropod species richness. We now require a high-throughput pipeline to operationalize this result so that we can (i) test competing explanations for tropical arthropod megadiversity, (ii) improve estimates of global eukaryotic species diversity, and (iii) use plant and arthropod communities as efficient proxies for each other, thus improving the efficiency of conservation planning and of detecting forest degradation and recovery. We therefore applied metabarcoding to Malaise-trap samples across two tropical landscapes in China. We demonstrate that plant species richness can accurately predict arthropod (mostly insect) species richness and that plant and insect community compositions are highly correlated, even in landscapes that are large, heterogeneous and anthropogenically modified. Finally, we review how metabarcoding makes feasible highly replicated tests of the major competing explanations for tropical megadiversity.


Asunto(s)
Biodiversidad , Insectos/clasificación , Plantas/clasificación , Clima Tropical , Animales , China , Código de Barras del ADN Taxonómico
14.
Transgenic Res ; 25(4): 499-505, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-26922585

RESUMEN

Surrogate species have a long history of use in research and regulatory settings to understand the potentially harmful effects of toxic substances including pesticides. More recently, surrogate species have been used to evaluate the potential effects of proteins contained in genetically engineered insect resistant (GEIR) crops. Species commonly used in GEIR crop testing include beneficial organisms such as honeybees, arthropod predators, and parasitoids. The choice of appropriate surrogates is influenced by scientific factors such as the knowledge of the mode of action and the spectrum of activity as well as societal factors such as protection goals that assign value to certain ecosystem services such as pollination or pest control. The primary reasons for using surrogates include the inability to test all possible organisms, the restrictions on using certain organisms in testing (e.g., rare, threatened, or endangered species), and the ability to achieve greater sensitivity and statistical power by using laboratory testing of certain species. The acceptance of surrogate species data can allow results from one region to be applied or "transported" for use in another region. On the basis of over a decade of using surrogate species to evaluate potential effects of GEIR crops, it appears that the current surrogates have worked well to predict effects of GEIR crops that have been developed (Carstens et al. GM Crops Food 5:1-5, 2014), and it is expected that they should work well to predict effects of future GEIR crops based on similar technologies.


Asunto(s)
Ecotoxicología/métodos , Plantas Modificadas Genéticamente/fisiología , Medición de Riesgo/métodos , Animales , Ambiente , Insectos , Plaguicidas/toxicidad
15.
Conserv Biol ; 28(6): 1584-93, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25115148

RESUMEN

Conserving or restoring landscape connectivity between patches of breeding habitat is a common strategy to protect threatened species from habitat fragmentation. By managing connectivity for some species, usually charismatic vertebrates, it is often assumed that these species will serve as conservation umbrellas for other species. We tested this assumption by developing a quantitative method to measure overlap in dispersal habitat of 3 threatened species-a bird (the umbrella), a butterfly, and a frog-inhabiting the same fragmented landscape. Dispersal habitat was determined with Circuitscape, which was parameterized with movement data collected for each species. Despite differences in natural history and breeding habitat, we found substantial overlap in the spatial distributions of areas important for dispersal of this suite of taxa. However, the intuitive umbrella species (the bird) did not have the highest overlap with other species in terms of the areas that supported connectivity. Nevertheless, we contend that when there are no irreconcilable differences between the dispersal habitats of species that cohabitate on the landscape, managing for umbrella species can help conserve or restore connectivity simultaneously for multiple threatened species with different habitat requirements.


Asunto(s)
Distribución Animal , Aves/fisiología , Mariposas Diurnas/fisiología , Conservación de los Recursos Naturales/métodos , Ecosistema , Especies en Peligro de Extinción , Ranidae/fisiología , Animales , Bosques , Modelos Biológicos , North Carolina
16.
Conserv Biol ; 28(2): 414-26, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24372620

RESUMEN

Surrogates, such as umbrella species, are commonly used to reduce the complexity of quantifying biodiversity for conservation purposes. The presence of umbrella species is often indicative of high taxonomic diversity; however, functional diversity is now recognized as an important metric for biodiversity and thus should be considered when choosing umbrella species. We identified umbrella species associated with high taxonomic and functional biodiversity in urban areas in Switzerland. We analyzed 39,752 individuals of 574 animal species from 96 study plots and 1397 presences of 262 plant species from 58 plots. Thirty-one biodiversity measures of 7 taxonomic groups (plants, spiders, bees, ground beetles, lady bugs, weevils and birds) were included in within- and across-taxa analyses. Sixteen measures were taxonomical (species richness and species diversity), whereas 15 were functional (species traits including mobility, resource use, and reproduction). We used indicator value analysis to identify umbrella species associated with single or multiple biodiversity measures. Many umbrella species were indicators of high biodiversity within their own taxonomic group (from 33.3% in weevils to 93.8% in birds), to a lesser extent they were indicators across taxa. Principal component analysis revealed that umbrella species for multiple measures of biodiversity represented different aspects of biodiversity, especially with respect to measures of taxonomic and functional diversity. Thus, even umbrella species for multiple measures of biodiversity were complementary in the biodiversity aspects they represented. Thus, the choice of umbrella species based solely on taxonomic diversity is questionable and may not represent biodiversity comprehensively. Our results suggest that, depending on conservation priorities, managers should choose multiple and complementary umbrella species to assess the state of biodiversity.


Asunto(s)
Artrópodos , Biodiversidad , Aves , Ciudades , Plantas , Animales , Conservación de los Recursos Naturales , Suiza
17.
Anim Conserv ; 27(2): 212-225, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38933688

RESUMEN

Umbrella species and other surrogate-species approaches to conservation provide an appealing framework to extend the reach of conservation efforts beyond single species. For the umbrella species concept to be effective, populations of multiple species of concern must persist in areas protected on behalf of the umbrella species. Most assessments of the concept, however, focus exclusively on geographic overlap among umbrella and background species, and not measures that affect population persistence (e.g., habitat quality or fitness). We quantified the congruence between the habitat preferences and nesting success of a high-profile umbrella species (greater sage-grouse, Centrocercus urophasianus, hereafter "sage-grouse"), and three sympatric species of declining songbirds (Brewer's sparrow Spizella breweri, sage thasher Oreoscoptes montanus, and vesper sparrow Pooecetes gramineus) in central Wyoming, USA during 2012 - 2013. We used machine-learning methods to create data-driven predictions of sage-grouse nest-site selection and nest survival probabilities by modeling field-collected sage-grouse data relative to habitat attributes. We then used field-collected songbird data to assess whether high-quality sites for songbirds aligned with those of sage-grouse. Nest sites selected by songbirds did not coincide with sage-grouse nesting preferences, with the exception that Brewer's sparrows preferred similar nest sites to sage-grouse in 2012. Moreover, the areas that produced higher rates of songbird nest survival were unrelated to those for sage-grouse. Our findings suggest that management actions at local scales that prioritize sage-grouse nesting habitat will not necessarily enhance the reproductive success of sagebrush-associated songbirds. Measures implemented to conserve sage-grouse and other purported umbrella species at broad spatial scales likely overlap the distribution of many species, however, broad-scale overlap may not translate to fine-scale conservation benefit beyond the umbrella species itself. The maintenance of microhabitat heterogeneity important for a diversity of species of concern will be critical for a more-holistic application of the umbrella species concept.

18.
Plants (Basel) ; 12(23)2023 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-38068692

RESUMEN

While transgenic Bacillus thuringiensis (Bt) maize provides pest resistance and a reduced application of chemical pesticides, a comprehensive environmental risk assessment is mandatory before its field release. This research determined the concentrations of Bt protein in plant tissue and in arthropods under field conditions in Gongzhuling City, northeastern China, to provide guidance for the selection of indicator species for non-target risk assessment studies. Bt maize expressing Cry1Ab/2Aj and non-transformed near-isoline were grown under identical environmental and agricultural conditions. Cry1Ab/2Aj was detected in plant tissues and arthropods collected from Bt maize plots during pre-flowering, flowering, and post-flowering. The expression of Cry1Ab/2Aj varied across growth stages and maize tissues, as well as in the collected arthropods at the three growth stages. Therefore, representative species should be chosen to cover the whole growing season and to represent different habitats and ecological functions. Dalbulus maidis (Hemiptera: Cicadellidae), Rhopalosiphum padi (Hemiptera: Aphididae), Heteronychus arator (Coleoptera: Scarabaeidae), and Somaticus angulatus (Coleoptera: Tenebrionidae) are suitable non-target herbivores. Propylea japonica (Coleoptera: Coccinellidae), Paederus fuscipes (Coleoptera: Staphylinidae), Chrysoperla nipponensis (Neuroptera: Chrysopidae), and spiders are suggested predators. Apis cerana and Apis mellifera ligustica (both Hymenoptera: Apidae) represent pollinators and Folsomia candida (Collembola: Isotomidae) decomposers.

19.
Biology (Basel) ; 12(4)2023 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-37106710

RESUMEN

The umbrella-species strategy has been proposed as an attainable tool to achieve multi-species and community conservation with limited investment. There have been many umbrella-related studies since the concept's inception; thus, a summary of global study efforts and recommended umbrella species is important for understanding advances in the field and facilitating conservation applications. Here, we collated 213 recommended umbrella species of terrestrial vertebrates from 242 scientific articles published during 1984-2021 and analyzed their geographic patterns, biological features, and conservation statuses to identify global trends in the selection of umbrella species. We found a considerable geographic bias: most studies and, consequently, recommended umbrella species are from the Northern Hemisphere. There is also a strong taxonomic bias, with grouses (order Galliformes) and large carnivores being the most popular umbrella species and amphibians and reptiles being largely overlooked. In addition, wide-ranging and non-threatened species were frequently recommended as umbrella species. Given the observed biases and trends, we caution that appropriate species need to be chosen for each location, and it is important to confirm that popular, wide-ranging species are effective umbrella species. Moreover, amphibians and reptiles should be investigated for their potential as umbrella species. The umbrella-species strategy has many strengths and, if applied appropriately, may be one of the best options in today's conservation research and funding landscape.

20.
Insect Sci ; 27(2): 375-388, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30260074

RESUMEN

Carabids (Coleoptera: Carabidae) seem to be suitable bioindicators of the environmental impacts of novel agrotechnologies, including deployment of the genetically engineered (GE) crops. In this article, we describe our effort to employ carabids in the environmental risk assessment (ERA). GE maize MON88017, its near-isogenic hybrid nontreated or treated with the soil insecticide chlorpyrifos, and two reference hybrids were used to compare three different ways how to utilize carabids in ERA. The analysis of abundance of all captured carabids or of the most abundant carabid species did not disclose any differences between the treatments. The analysis based on the categories of functional traits revealed distinct features of some treatments and proved suitable for ERA because it permitted field data transportability in spite of different species compositions. Our results indicate that GE maize has no detrimental environmental effect. On the other hand, we found significant trends toward lower abundance and lower species number (including analysis of all carabid species together) in plots treated with the insecticide, and some tendencies to higher abundance and higher species number in plots sown with the reference hybrid PR38N86. Using functional group indicators allows identification of unintended changes in ecological functions of agroecosystem and comparability across geographies. We recommend data evaluation at the level of the categories of functional traits in ERA of GE crops and other agricultural practices.


Asunto(s)
Biodiversidad , Escarabajos , Biomarcadores Ambientales , Animales , Cloropirifos , Insecticidas , Plantas Modificadas Genéticamente , Medición de Riesgo/métodos , Zea mays
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