Biodiversity and Conservation最新文献

A contemporary appraisal of the extent to which international conservation law provides for the protection of commonplace biodiversity. It is argued that in light of the current extinction crisis, biodiversity would be better served if the law focused more on protecting common species rather than just the rare and endangered. Particular attention is paid to the rationales behind conservation regulation and how different understandings of the value have influenced the law’s development. Key conservation mechanisms, namely area-based management, species-focused mechanisms and the ecosystem approach, are analysed in relation to how they protect commonplace biodiversity, before a case study on the legal protection of plants is presented. What is suggested is that international conservation law has failed to keep pace with key developments in conservation science, resulting in a regulatory system that appears structurally incapable of halting biodiversity loss. Reforming the law so that it provides greater protection to commonplace biodiversity would be an important first step in responding to this.

Habitat fragmentation is one of the main causes of the global loss of plant biodiversity. It is also one of the major challenges in Ethiopia, where fragmented forest patches of different sizes have been observed. These patches of forest, especially in the highlands of northern Ethiopia, are mainly confined to churches. These remnant forest patches have long been said to have negative impacts (habitat amount hypothesis). Recently, however, there is evidence that these small patches of remnant forest may harbour more species than relatively large patches of the same area. We tested this hypothesis in the remnant church forests of the Ethiopian highlands using different plant growth forms. Ten church forests of different sizes were selected in which transects were established from the forest edges to the interior. A total of 56 20 × 20 m plots were used for plant sampling. All trees, shrubs and herbs within the plots were recorded, collected and identified. We found that the effects of forest fragmentation on plant diversity, abundance and composition varied with plant growth forms. In contrast to the habitat amount hypothesis, small forest fragments were found to support more tree species than relatively large forest fragments, suggesting the role of small forest fragments in maintaining species diversity. We found that soil moisture changes with fragment size but has no significant effect on plant abundance and diversity of plant growth forms. Our results indicate that a shift in conservation priorities may be needed to recognize the value of small fragmented patches of forest for biodiversity conservation, as a lack of protection of small patches of forest can lead to high cumulative impacts on biodiversity loss.

Habitat management is necessary for the conservation of threatened species, yet best practices in fragmented human-dominated landscapes have remained difficult to generalise. We show that multi-scale vegetation management decisions in heathlands can be supported by integrating opportunistic citizen science data and multispectral satellite data. Opportunistic observations were gathered from ten typical, mostly threatened animal species of dry heathlands in Flanders as point records with specified precision. We considered vegetation structure at the local scale, quantified by image texture within 0.25 ha derived from multispectral satellite data, and heathland heterogeneity at the habitat scale, quantified by the diversity in heathland vegetation communities within 50 ha. Additionally, locations inside heathlands were attributed to an open, closed or anthropogenic landscape context. Point process models were used to test the impact of heathland size, vegetation structure and heathland heterogeneity on the habitat suitability of the studied species. We found that (1) heathland vegetation management can benefit habitat suitability in fragmented heathlands, but with a different approach for local management of vegetation structure in small versus large heathlands (e.g. due to micro-fragmentation effects), (2) the landscape induces positive and negative edge effects (e.g. due to a high versus low resource availability), especially in small heathlands and (3) habitat suitability is driven by both vegetation structure and heathland heterogeneity but with different relative importance for birds, butterflies and grasshoppers (e.g. due to differences in mobility).

Abstract

Whilst the importance of foundation species for biodiversity conservation has been largely acknowledged (e.g., coral and bivalve reefs, seagrass, kelp and rhodolith beds), the role of their associated species as secondary habitat engineers has just begun to be appreciated. Here, we evaluated whether secondary engineering of rhodolith beds by the sand tilefish Malacanthus plumieri influences the composition and β-diversity of benthic macroinvertebrates and reef fish assemblages. Our findings indicate that, by selecting, relocating, and rearranging rhodoliths into mounds, M. plumieri creates a distinctive habitat for macroinvertebrates and fishes. M. plumieri mounds increase fish abundance by 57% in rhodolith beds, with an 82% species turnover rate between mounds and non-mounded areas. In contrast, the macroinvertebrates in M. plumieri mounds are largely a subset of the species from non-mounded areas, with an 86% species nestedness rate. Despite decreasing the abundance of macroinvertebrates in the mounds by half, M. plumieri increases the heterogeneity and structural complexity of rhodolith beds, affecting the composition of associated fish assemblage at a larger spatial scale. Our results suggest that, by increasing the structural complexity of rhodolith beds and shaping their associated biodiversity, the abundance of M. plumieri mounds could be a useful proxy to define priority areas for conservation across the South Atlantic rhodolith beds, especially in the light of ongoing impacts related to offshore oil exploitation, overfishing and carbonate mining.

Mozambique has undocumented forest patches that are cultural landscapes and locally protected as heritage sites. Using the case of Inhambane Province, in this paper, we present the status and purposes of forest patches protected by local communities and discuss threats working against local protection. Findings point out that these heritage forests are reservoirs for biodiversity conservation and the local system of conservation is effective, but there are challenges local custodians face to safeguard heritage forests, ranging from illegal logging, misrecognition of customary protection and lack of legislation enforcement. We argue that the existence of heritage forests requires collaboration between entities dealing with forests, heritage and conservation. We suggest strategies to increase protection in the Inhambane Province and the Mozambique context. This will support local institutions in the protection of heritage forests, as biodiversity reservoirs and in keeping heritage practices and the customary protection of heritage forests alive.

Citizen science has become a crucial tool in biodiversity monitoring, often facilitated by the diffusion of mobile devices, such as smartphones and tablets. High costs of professional equipment often limit large-scale monitoring, particularly in bat monitoring programmes based on acoustic surveys. Here we present the potential of using mobile devices for bat monitoring, allowing for large-scale, volunteer-based monitoring programmes. We initially compared mobile devices’ performance with a professional bat detector for recording low-frequency bat calls. We then conducted a citizen science pilot study to test the method’s feasibility in a real-world setting, recording echolocation and social calls of nine European bat species. We found high similarity in spectrogram quality (0.74 ± 0.09 for Samsung, 0.90 ± 0.01 for Huawei, 0.86 ± 0.09 for Xiaomi, 0.69 ± 0.09 for Apple) and average peak frequency (differences of 0.2 ± 0.5 kHz for Samsung, 0.1 ± 0.7 kHz for Huawei, 0.5 ± 1.0 kHz for Xiaomi, 0.1 ± 0.8 kHz for Apple) between calls recorded by mobile devices and professional bat detectors. The number of recorded bat calls per sampling session was also similar. However, differences in sound quality and effectiveness among mobile device brands were found. iOS devices outperformed professional detectors at recording bat calls at increasing distances. The citizen science pilot study tested 35 mobile device models, all of which effectively recorded bats. This study suggests that mobile devices could be an accessible, no-cost tool for large-scale bat monitoring. Incorporating mobile devices into existing monitoring networks or creating new dedicated programmes could not only enhance data collection, but also boost public knowledge and awareness about bats, ultimately promoting informed decision-making and better conservation strategies.

Functional diversity has proven to be more responsive than traditional taxonomic diversity to alterations for a wide set of communities, especially in aquatic ecosystems. Habitat alterations are among the most relevant causes of biodiversity loss in freshwater ecosystems, nevertheless their effect on functional diversity has been scarcely investigated so far. In this study, functional diversity of fish communities in the River Po basin, north Italy, were related to habitat quality at different spatial scales. Land use and riparian vegetation were identified as the most influent factors on freshwater fish functional diversity. On the other hand, habitat descriptors at smaller scale did not influence functional diversity of fish. The evidenced responses were driven by the contribution of exotic species, which maximized ecological niche occupancy, either by exploiting increased habitat heterogeneity or by interaction with native species. Moreover, traits filtering, disadvantaging large predators such as salmonids, was also observed in the studied communities, but likely this effect was related to other factors than habitat alterations. Overall, this study confirms that land use changes can be considered as valid proxies for anthropogenic alterations. Moreover, possible effects at ecosystem level, also related to the spread of exotic species, could be hypothesized, giving that traits mostly influencing the observed patterns of diversity in communities were related to trophic niche, a factor that has been associated with crucial processes like nutrient cycling or energy transfer.

Giraffe (Giraffa spp.) numbers and their habitat have drastically declined throughout Africa over the last century due to various threats linked to anthropogenic impacts including habitat loss and fragmentation, disease, poaching, and climate change. In Kenya, the Nubian giraffe (G. camelopardalis camelopardalis) population decreased significantly up until the late 1980s. As a result of increased conservation efforts, the Nubian giraffe population has rebounded since the early 1990s, however, it remains predominantly extralimital and/or restricted to closed protected areas in central and western Kenya. In this paper, we set out to assess historical and current population numbers and trends of Nubian giraffe in Kenya, and highlight the conservation efforts that are applied to conserve this Critically Endangered taxon. We reviewed published manuscripts and grey literature, wildlife authority records and interviewed landowners with Nubian giraffe populations. We also conducted photographic surveys in three national parks and reserves where anecdotal reports suggested that the largest populations of Nubian giraffe occurred. We found that from a low of (sim) 130 individuals remaining in the wild and near extinction in the mid-1970s, the Nubian giraffe population has rebounded to (sim) 1,042 in 14 populations in Kenya, which represents an increase of more than 700%. This conservation success story is attributed to targeted management efforts, in particular conservation translocations and the increased monitoring of populations. At the same time, various factors including habitat loss and fragmentation, and infrastructure developments, linked with the increasing human population continue to pose a threat to their survival in the country. We place our findings in the broader context of population ecology and present opportunities for conservation research as well as recommendations that inform the management of this critical population of concern.

Invasive alien species (IAS) are widely recognized as a major threat to ecosystems globally. Despite the growing interest and research effort on biological invasions, the impact of IAS on both terrestrial and aquatic subterranean habitats remains considerably under-studied in comparison to other environments. The Convention on Biological Diversity (CBD) has established global targets to mitigate the impacts of IAS, emphasizing the need for countries, organizations, and the scientific community to identify gaps in knowledge, monitoring, and management strategies for IAS. To this end, we mapped knowledge gaps in biological invasions of subterranean habitats that emerged from the first systematic surveys of the available information. We suggest that there are five main gaps restricting our ability to understand and tackle biological invasions in subterranean ecosystems. Given the vulnerability of subterranean ecosystems and the lack of attention they have received in conservation policies, it is crucial to increase research emphasis on IAS. This opinion paper aims to stimulate such efforts and contribute to the preservation of these ecosystems.

Southeast Asia experiences some of the highest deforestation in the world. Loss of tropical forest typically leads to widespread habitat fragmentation, with detrimental effects on dispersal ability and gene flow—particularly for large carnivores. We conducted mtDNA and microsatellite analysis to assess—for the first time—contemporary patterns of genetic diversity in the Malayan tiger. We collected 295 suspected carnivore samples in Peninsular Malaysia, from which we identified 26 as originating from tiger using 16 polymorphic microsatellite loci, comprising 22 individual tigers. Despite limitations of the study, our findings suggest tiger subpopulations in the north of the peninsula maintain some genetic connectivity and migration between two putative geographic subpopulations in the Main Range and Greater Taman Negara, with negligible population segregation due to dispersal barriers such as road infrastructure. We identified consistently lower levels of genetic diversity in tigers in the Greater Taman Negara region compared to tigers in the Main Range and small but emerging differences in nuclear and mitochondrial genetic diversity. Our mtDNA haplotype and nuclear DNA analyses suggest the levels of genetic diversity in Malayan tigers may be amongst some of the lowest of the surviving tiger subspecies, though the study is limited both in scale and genomic loci. Our findings are consistent with an expected lag between the rapid decline of tigers in Peninsular Malaysia by over 95% in the last 70 years and observed differences in their levels of genetic diversity.