Prey animals may lack appropriate predator avoidance behaviours to novel predators, which has contributed to the decline of many species worldwide following human introduction of novel predators. ...Excluding novel predators from conservation reserves has been used to attempt to recover naïve species with mixed success. However, in the absence of predators, prey naiveté can be exacerbated. Reintroducing native predators has been suggested as a solution to addressing this problem and may act as a stepping stone to improve behavioural responses to novel predators. We tested the behavioural responses of two prey species, the burrowing bettong, Bettongia lesueur, and spinifex hopping mouse, Notomys alexis, to the reintroduction of a native predator, the western quoll, Dasyurus geoffroii, and determined whether exposure to a native predator improved their antipredator responses to introduced feral cats, Felis catus. Quoll-exposed bettongs spent less time engaged in inattentive foraging behaviours compared to control (nonpredator exposed) bettongs but did not discriminate between predator and nonpredator visual or olfactory cues (native or novel). Quoll-exposed spinifex hopping mice modified their foraging in open habitats and increased wariness in the presence of quoll stimuli, whereas cat-exposed hopping mice only exhibited increased wariness in the presence of cat stimuli. Our results show that reintroductions of native predators improved general antipredator responses in native prey species, but there was only weak evidence that this led to an improved response to introduced predators. However, reintroducing native predators improved general antipredator behaviour in ontogenetically naïve populations which may make them more suitable for releases outside conservation fences where novel predators are present.
•Reintroductions of native predators improve general antipredator responses in prey•Quoll-exposed bettongs spent less time in inattentive foraging than controls•Quoll-exposed hopping mice recognized foraging risk in open habitats•Limited evidence whether this improves discrimination towards novel predators
Large herbivores are considered a natural and important determinant for high biodiversity in woodland habitats and have been increasingly reintroduced to nature areas across Europe with the aim of ...re-establishing natural processes to promote and protect biodiversity. One of the herbivore species playing an increasing role in ecological restoration initiatives is the European bison – the largest extant terrestrial mammal in Europe. However, despite numerous reintroductions of bison for biodiversity purposes, the empirical evidence for their impact is highly limited. Using permanent plots, we investigated the impact of European bison on ground vegetation in forest habitats over a period of eight years. The bison increased the species richness of vascular plants, though mainly to the benefit of graminoids. The effect varied, however, among forest types, with the strongest effect in oak forests with dense and abundant ground vegetation while beech forests characterized by full canopy cover were unaffected. Bison also benefitted bryophytes, which increased in abundance, indicating a generally altered competitive environment with reduced dominance. These results thus provide some of the first empirical evidence, indicating that European bison can promote plant species diversity in forest habitats, by removal of plant biomass, zoochorous seed dispersal, and creation of microhabitat. We thus suggest that introduction of European bison to mixed light woodlands can be a good strategy, benefitting both biodiversity and the conservation of the threatened herbivore species itself.
•European bison increase species richness of vascular plants in forest.•Bison grazing increases abundance of bryophytes.•Effects of bison grazing vary among forest habitat types.•The strongest effect is in habitats with dense and abundant ground vegetation.
“Rewilding” is an increasingly influential concept, though the widespread, if unplanned, rewilding that takes place in “no man’s land” or demilitarized zones has received limited attention from ...environmental historians, and none at all from historians of islands. When former military bases or conflict areas are opened up to development and tourism, the continued presence of the new non-human residents poses both opportunities and challenges. This article will consider two late twentieth-century examples, Quemoy and the Falklands, where the classic traits of insularity—the natural limit of resources and the geographical separation from the mainland—were compounded by the presence of minefields and stringent military control, permitting the emergence of an insular military ecology. The later discovery of the “rewilded” areas by journalists, nature writers, and companies promoting tourism invited reflection on the ability of nature to regenerate and on the larger meanings of post-conflict landscapes. Islands figure here, once again, as sites of the production of knowledge and as opportunities for experimentation, yet in ways which differ from the examples considered by earlier historians of islands.
We have been field observers of tropical insects on four continents and, since 1978, intense observers of caterpillars, their parasites, and their associates in the 1,260 km
of dry, cloud, and rain ...forests of Área de Conservación Guanacaste (ACG) in northwestern Costa Rica. ACG's natural ecosystem restoration began with its national park designation in 1971. As human biomonitors, or "insectometers," we see that ACG's insect species richness and density have gradually declined since the late 1970s, and more intensely since about 2005. The overarching perturbation is climate change. It has caused increasing ambient temperatures for all ecosystems; more erratic seasonal cues; reduced, erratic, and asynchronous rainfall; heated air masses sliding up the volcanoes and burning off the cloud forest; and dwindling biodiversity in all ACG terrestrial ecosystems. What then is the next step as climate change descends on ACG's many small-scale successes in sustainable biodevelopment? Be kind to the survivors by stimulating and facilitating their owner societies to value them as legitimate members of a green sustainable nation. Encourage national bioliteracy, BioAlfa.
According to the biodiversity hypothesis of immune-mediated diseases, lack of microbiological diversity in the everyday living environment is a core reason for dysregulation of immune tolerance and – ...eventually – the epidemic of immune-mediated diseases in western urban populations. Despite years of intense research, the hypothesis was never tested in a double-blinded and placebo-controlled intervention trial.
We aimed to perform the first placebo-controlled double-blinded test that investigates the effect of biodiversity on immune tolerance.
In the intervention group, children aged 3–5 years were exposed to playground sand enriched with microbially diverse soil, or in the placebo group, visually similar, but microbially poor sand colored with peat (13 participants per treatment group). Children played twice a day for 20 min in the sandbox for 14 days. Sand, skin and gut bacterial, and blood samples were taken at baseline and after 14 days. Bacterial changes were followed for 28 days. Sand, skin and gut metagenome was determined by high throughput sequencing of bacterial 16 S rRNA gene. Cytokines were measured from plasma and the frequency of blood regulatory T cells was defined as a percentage of total CD3 +CD4 + T cells.
Bacterial richness (P < 0.001) and diversity (P < 0.05) were higher in the intervention than placebo sand. Skin bacterial community, including Gammaproteobacteria, shifted only in the intervention treatment to resemble the bacterial community in the enriched sand (P < 0.01). Mean change in plasma interleukin-10 (IL-10) concentration and IL-10 to IL-17A ratio supported immunoregulation in the intervention treatment compared to the placebo treatment (P = 0.02). IL-10 levels (P = 0.001) and IL-10 to IL-17A ratio (P = 0.02) were associated with Gammaproteobacterial community on the skin. The change in Treg frequencies was associated with the relative abundance of skin Thermoactinomycetaceae 1 (P = 0.002) and unclassified Alphaproteobacteria (P < 0.001). After 28 days, skin bacterial community still differed in the intervention treatment compared to baseline (P < 0.02).
This is the first double-blinded placebo-controlled study to show that daily exposure to microbial biodiversity is associated with immune modulation in humans. The findings support the biodiversity hypothesis of immune-mediated diseases. We conclude that environmental microbiota may contribute to child health, and that adding microbiological diversity to everyday living environment may support immunoregulation.
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•Homogenized, microbiologically rich soil can be used to rewild urban playgrounds.•Placebo-controlled intervention promotes immunomodulation among urban children.•Shifts in skin microbiota are associated with interleukin-10 and T cell frequencies.•Enhanced immunomodulation is related to microbiota; sensing green is not needed.•The findings support the biodiversity hypothesis of immune-mediated diseases.
Are we ready for back-to-nature crop breeding? Palmgren, Michael G.; Edenbrandt, Anna Kristina; Vedel, Suzanne Elizabeth ...
Trends in plant science,
03/2015, Volume:
20, Issue:
3
Journal Article
Peer reviewed
•Reverse breeding is here defined as introduction of ancestral traits into crops.•Reverse breeding provides a promising future path for sustainable agriculture.•Current legislations may define plants ...obtained by reverse breeding as GMOs.
Sustainable agriculture in response to increasing demands for food depends on development of high-yielding crops with high nutritional value that require minimal intervention during growth. To date, the focus has been on changing plants by introducing genes that impart new properties, which the plants and their ancestors never possessed. By contrast, we suggest another potentially beneficial and perhaps less controversial strategy that modern plant biotechnology may adopt. This approach, which broadens earlier approaches to reverse breeding, aims to furnish crops with lost properties that their ancestors once possessed in order to tolerate adverse environmental conditions. What molecular techniques are available for implementing such rewilding? Are the strategies legally, socially, economically, and ethically feasible? These are the questions addressed in this review.
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Predators shape ecosystem structure and function through their direct and indirect effects on prey, which permeate through ecological communities. Predators are often perceived as competitors or ...threats to human values or well-being. This conflict has persisted for centuries, often resulting in predator removal (i.e. killing) via targeted culling, trapping, poisoning, and/or public hunts. Predator removal persists as a management strategy but requires scientific evaluation to assess the impacts of these actions, and to develop a way forward in a world where human-predator conflict may intensify due to predator reintroduction and rewilding, alongside an expanding human population. We reviewed literature investigating predator removal and focused on identifying instances of successes and failures. We found that predator removal was generally intended to protect domestic animals from depredation, to preserve prey species, or to mitigate risks of direct human conflict, corresponding to being conducted in farmland, wild land, or urban areas. Because of the different motivations for predator removal, there was no consistent definition of what success entailed so we developed one with which to assess studies we reviewed. Research tended to be retrospective and correlative and there were few controlled experimental approaches that evaluated whether predator removal met our definition of success, making formal meta-analysis impossible. Predator removal appeared to only be effective for the short-term, failing in the absence of sustained predator suppression. This means predator removal was typically an ineffective and costly approach to conflicts between humans and predators. Management must consider the role of the predator within the ecosystem and the potential consequences of removal on competitors and prey. Simulations or models can be generated to predict responses prior to removing predators. We also suggest that alternatives to predator removal be further developed and researched. Ultimately, humans must coexist with predators and learning how best to do so may resolve many conflicts.
•Predators are essential components of ecosystems but can threaten humans.•Economics, conservation, or security may inspire culls but success is poorly defined.•Across environments and taxa, we identified infrequent success of predator removal.•Consideration of demographics, sustainable yield, and problem individuals are relevant.•Co-existence is possible but typically requires research to inform co-existence strategies.
There is an increasing recognition that, although the climate change and biodiversity crises are fundamentally connected, they have been primarily addressed independently and a more integrated global ...approach is essential to tackle these two global challenges.
Nature‐based Solutions (NbS) are hailed as a pathway for promoting synergies between the climate change and biodiversity agendas. There are, however, uncertainties and difficulties associated with the implementation of NbS, while the evidence regarding their benefits for biodiversity remains limited.
We identify five key research areas where incomplete or poor information hinders the development of integrated biodiversity and climate solutions. These relate to refining our understanding of how climate change mitigation and adaptation approaches benefit biodiversity conservation; enhancing our ability to track and predict ecosystems on the move and/or facing collapse; improving our capacity to predict the impacts of climate change on the effectiveness of NbS; developing solutions that match the temporal, spatial and functional scale of the challenges; and developing a comprehensive and practical framework for assessing, and mitigating against, the risks posed by the implementation of NbS.
Policy implications. The Conference of the Parties (COP) for the United Nations Framework Convention on Climate Change (COP26) and the Convention on Biological Diversity (COP15) present a clear policy window for developing coherent policy frameworks that align targets across the nexus of biodiversity and climate change. This window should (a) address the substantial and chronic underfunding of global biodiversity conservation, (b) remove financial incentives that negatively impact biodiversity and/or climate change, (c) develop higher levels of integration between the biodiversity and climate change agendas, (d) agree on a monitoring framework that enables the standardised quantification and comparison of biodiversity gains associated with NbS across ecosystems and over time and (e) rethink environmental legislation to better support biodiversity conservation in times of rapid climatic change.
Policy implications. The Conference of the Parties (COP) for the United Nations Framework Convention on Climate Change (COP26) and the Convention on Biological Diversity (COP15) present a clear policy window for developing coherent policy frameworks that align targets across the nexus of biodiversity and climate change. This window should (a) address the substantial and chronic underfunding of global biodiversity conservation; (b) remove financial incentives that negatively impact biodiversity and/or climate change; (c) develop higher levels of integration between the biodiversity and climate change agendas; (d) agree on a monitoring framework that enables the standardised quantification and comparison of biodiversity gains associated with NbS across ecosystems and over time; and (e) rethink environmental legislation to better support biodiversity conservation in times of rapid climatic change.
There is growing interest in aligning the wildlife conservation and restoration agenda with climate change mitigation goals. However, the presence of large herbivores tends to reduce aboveground ...biomass in some open-canopy ecosystems, leading to the possibility that large herbivore restoration may negatively influence ecosystem carbon storage. Furthermore, belowground carbon storage is often ignored in these systems, despite the wide recognition of soils as the largest actively-cycling terrestrial carbon pool. Here, we suggest a shift away from a main focus on vegetation carbon stocks, towards inclusion of whole ecosystem carbon persistence, in future assessments of large herbivore effects on long-term carbon storage. Failure to do so may lead to counterproductive biodiversity and climate impacts of land management actions.
•Forest cover increased up to 80 % in sites between 0 and 30 years after abandonment of agriculture.•Natural tree colonization is faster closer to existing forests or other woody vegetation.•Loamy ...soils increase the speed of colonization and the number of woody species.•Passive restoration is a feasible method to create diverse forests.
Natural colonization of abandoned agricultural soils has been proposed as a cost-effective strategy for simultaneously mitigating the climate crisis, restoring ecological integrity, and promoting the re-establishment of native biodiversity. The success and speed at which forests develop in the presence of land-use legacies are highly variable, and empirical knowledge on the drivers of the initial phase of temperate forest colonization in a range of site conditions is lacking. We analyzed and compared drivers of the initial three decades of natural forest colonization in 33 afforestation sites laid out between 1990 and 2018, in Denmark. We analyzed how the age of colonization, size of the area, soil type, topography, and abundance of neighboring woody vegetation influenced woody vegetation cover, species richness, and variation in vegetation structure of the colonizing woody species. We found that woody vegetation cover, species richness, and structural variation increased significantly with time since abandonment. Woody vegetation cover was significantly higher in sites with abundant neighboring vegetation and on loamy soils compared to sand or clay. Woody vegetation cover tended to be higher in sites with sloping terrain. Species richness increased significantly in sites with loamy or clay soil and sites with sloping terrain. After accounting for the other drivers, none of the elements were influenced by the size of the area. The results suggest that time since abandonment, neighboring mature woody vegetation, soil and topography are key drivers of the different elements of colonization. This knowledge can be used to prioritize areas for natural colonization and to improve active afforestation methods, especially in new forests where the main focus is on nature quality and biodiversity.
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