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Understanding species’ distributions often requires taking into consideration the characterization of the environment at different spatial scales. The habitat characteristics of the endangered fire salamander, S. infraimmaculata, have received little attention. In this study, at this species’ most peripheral and xeric limit (Mt. Carmel, Israel), we examined predictors of the larval distribution of S. infraimmaculata at aquatic-breeding sites at both local and landscape scales. We investigated the predictive power of environmental variables using two methods: generalized linear models and conditional inference trees (CTREE). Both multi-model approaches yielded similar results. At the local site scale, hydroperiod predicted breeding site use. At the landscape scale, Salamandra presence was best predicted by proximity to other breeding sites. In addition, our study indicates that sites selected for breeding are far from roads and agricultural fields. Overall, this study demonstrates that ultimately, both local and landscape scale predictors are necessary to understand properly a species’ habitat requirements and thus can help in planning future management around the breeding sites.  相似文献   

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In this study, we evaluate phylogeographic patterns and predictions of ecological niche modelling (ENM) for Eugenia uniflora (Myrtaceae), a widely distributed taxon in the Atlantic forest domain, to understand the effect of past climatic oscillations on the demographic history of this species. An analysis of phylogeographic population structure and demography was conducted on E. uniflora from 46 localities in natural environments across the distribution range of the species based on three plastid markers. ENM was also performed to predict suitable environments and areas of dramatic decrease in future suitability for the species under distinct representative concentration pathways (RCPs). Eugenia uniflora exhibited higher haplotype and nucleotide diversity in the southern part of its distribution than in the northern part. Two divergent lineages were revealed in the phylogenetic analysis of haplotypes, with an estimated divergence at c. 4.9 Mya. The populations in the northern and central regions of the range probably experienced population growth, whereas populations in the southern region are marked by historical demographic stability. ENM results indicate that the distribution of E. uniflora was fragmented in cool periods and was broader and more connected during warm periods during Pleistocene. The results suggest distinct evolutionary histories in southern to northern populations, indicating region‐specific responses to changes.  相似文献   

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Socially acquired information is widespread in the animal kingdom.Many individuals make behavioral decisions based on such socialinformation. In particular, individuals may decide to leaveor select their habitat based on social information. Few studieshave investigated the role of density-related information, apotential social cue about habitat quality in dispersal. Here,we tested for the possibility that the phenotype of intrudercommon lizards (Lacerta vivipara) may inadvertently carry informationabout their natal population density. We found that such informationuse is likely. The behavior of focal lizard was influenced bythe natal population density of the intruder it was interactingwith. This suggests that individuals may use the behavior ofothers to acquire appropriate information about surroundingsand to base spatial decisions on this information. Density-relatedinformation may then affect individual movement decisions andthus metapopulation dynamics.  相似文献   

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Prochilodus magdalenae is an endemic freshwater fish that occurs in the Magdalena, Sinú and Atrato hydrographic basins. It has an important economic role and is a food resource for the artisanal fishing communities. Its socioeconomic importance contrasts with the current status of its fisheries, where stocks are being depleted. Considering its importance and lack of information on its genetic structure, we used seven microsatellite markers to assess the genetic structure of wild populations of P. magdalenae. The genetic diversity was assessed and the population genetic structure was estimated through Fst, analysis of molecular variance and Bayesian analysis. A total of 290 alleles were found in all loci throughout all population. The high polymorphism contrasts with the levels of observed heterozygosity (Ho = 0.276), which are the lowest values recorded for the family. We found three populations of bocachico coexisting throughout the studied system, contradicting the hypothesis that freshwater migratory fish form panmictic populations. These results on the genetic structure of P. magdalenae constitute tools for a better understanding of the behavior and biology of this species, contributing to fish management and conservation programs.  相似文献   

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The eastern portion of the Camargue in southern France is divided into two parts: a natural wetland area of 2800 ha and an agricultural area of 5045 ha. In 1984 and 1989, a new protected area (1000 ha) was created on two contiguous former hunting estates. Analysis of aerial photographs (1968–1998) in conjunction with a field survey revealed, from 1984 to 1998, an increase of management for waterfowl hunting in natural wetlands located on the periphery of the new reserve, and a similar increase in the agricultural area amongst residual wetlands and former rice fields. Based on monthly aerial censuses, the size of the waterfowl population in the winter increased in this part of the delta by a factor of 3.8 following the creation of the reserve. Our results suggest that the creation of a reserve on former hunting estates resulted in greater attractiveness for ducks but also in the development of commercial hunting activity around the edge. This development increased fragmentation and uniformity of natural areas, including the loss of the unique Cladium mariscus habitat in the Camargue and resulted in the spatial expansion of waterfowl hunting areas in agricultural areas. It is associated with an increase in financial profit from waterfowl hunting. Our study highlights unexpected costs for nature conservation associated with the creation of a reserve. It illustrates the need for new models of wetland conservation where protection goals are not restricted to reserves, but also integrate conservation and economic development outside the protected areas.  相似文献   

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