Reintroduction Of Native Species Research Articles

Reintroduction of native species in an ecological restoration program from a quartzite area of campos rupestres

Reintroduction of native species in an ecological restoration program from a quartzite area of campos rupestres

Morphometry, Growth, and Condition of Hatchery-Reared Cisco (<i>Coregonus artedi</i>) and Bloater (<i>Coregonus hoyi</i>)

The re-introduction of native species that have been extirpated or in low abundance in the Great Lakes has been a binational initiative between the United States and Canadian governments. Recently, new management programs have been underway that use current hatchery facilities for the restoration of native forage fishes in Lake Ontario. These species include Bloater (<i>Coregonus hoyi</i>), which has been extirpated from Lake Ontario for approximately four decades, and Cisco (<i>C. artedi</i>), which exists at a fraction of its former abundance. We assessed morphometrics, length-weight relationships, and condition factors during early life development for eight cohorts of Cisco and Bloater reared from 2012-2019. Weekly samples for Cisco and Bloater were measured from hatch until release (29-45 weeks, 133-1,002 samples annually). Head width, gape, mandible length, and mouth height metrics were all larger for Cisco than Bloater at any given size but increased at similar rates for both species. Average condition factors for Cisco and Bloater were 0.54317 and 0.55892, respectively. This information may also improve field identification of these species, helping managers evaluate the relative success of different release strategies for rehabilitation of populations of these native species.

The benefits of publishing in society‐owned scientific journals

The benefits of publishing in society‐owned scientific journals

Using stable isotopes to analyse extinction risks and reintroduction opportunities of native species in invaded ecosystems

Invasive non-native species have pervasive impacts on native biodiversity, including population extirpations and species extinctions. Identifying reasons why a population of a native species is extirpated following an invasion often relies on literature-based results of anecdotal observations. The well-established schemes of existing risk assessments for invasive species assume that a species’ information (e.g. impacts or behavioural and biological traits) can be projected from one area to another to estimate the potential impact of a species in another environment. We used stable isotope data (δ13C, δ15N) from both invaded and uninvaded communities to predict such invasion impacts by reconstructing trophic relationships. This approach was tested on a community within a protected lake in Northern Spain where, following the introductions of non-native species, the last resident native species (the common tench Tinca tinca, the European eel Anguilla anguilla, and the whirligig beetle Gyrinus sp.) had been extirpated. Through the application of this novel approach, we found evidence that native species’ declines were related to direct predation by and resource overlap with non-native species, which occurred in conjunction with habitat modification. Using this approach, we outlined the mechanisms involved in the extirpation of native species in the post-invasion period. To compensate for losses of native species induced by invasions of non-native species, native species reintroductions might be an appropriate tool. For this, we further suggested and discussed a novel approach that predicts the outcome of arising interactions by superimposing stable isotope data from alternative sources to better estimate the success of native species´ reintroductions.

Using multiple palaeoecological indicators to guide biodiversity conservation in tropical dry islands: The case of São Nicolau, Cabo Verde

Tropical dry islands are currently facing major challenges derived from anthropogenic and climatic pressures. However, their trajectories of environmental change, which could provide relevant information applicable to biodiversity conservation, remain understudied. This is mainly due to poor micro-fossil preservation and irregular sediment deposition. Multi-proxy palaeoecological analyses spanning decades to 1000s of years can add perspective as to how vegetation, fungal communities, and the fauna responded to previous natural and anthropogenic disturbances. In São Nicolau, Cabo Verde, we used palaeoecological methods to analyse a highland soil profile (1000 m asl) dated to 5900 cal yr BP. We analysed how vegetation (abundances in pollen of native and introduced species, and leaf wax n-alkanes), ferns and fungal communities (abundance of non-pollen palynomorphs) varied over time in relation to fire (charcoal concentration) and erosion regimes (grain sizes and elemental composition). Between 5000 and 400 cal yr BP the highlands held native woody taxa such as Euphorbia tuckeyana, Dracaena draco subsp. caboverdeana, and Ficus, taxa that can be used for future reforestation programmes. From 400 cal yr BP to the present day, replacement of native taxa by introduced and cultivated taxa (Pinus, Eucalyptus, Asystasia, Opuntia) has occurred. Vegetation burning and grazing caused loss of vegetation and erosion, acting as conjoined drivers of scrubland degradation. This dataset helps to set historically contextualised restoration goals such as the re-introduction of native species, monitoring of recently introduced species and control of free grazing. This can serve as a model system for the conservation of tropical dry islands' biodiversity.

Animal reintroductions in peopled landscapes: moving towards urban-based species restorations in New Zealand

Urban areas are highly modified landscapes that can support significant biodiversity, including threatened species, although native species are usually present at low densities and several native species will be absent. The most powerful tool for increasing urban biodiversity is supporting existing biodiversity through appropriately designed and managed public and private greenspaces, and improving habitat quality. However, if a more proactive strategy is required to overcome recolonisation barriers, then reintroduction is another powerful tool to enhance biodiversity across urban landscapes. The health of cities, in terms of biodiversity, ecosystem services, and the quality of the nature experiences accessed by adults and children largely depends on how much human communities value and know about nature. While community-driven habitat restorations can improve biodiversity and increase human–nature connection, reintroduction of appropriate species could fill ecological gaps that would otherwise remain empty, and further enrich biodiversity in residents’ nearby neighbourhoods. New Zealand is currently a hotspot of reintroduction activity, but these take place in relatively unmodified terrestrial sites, such as national parks, restored offshore islands, and fenced eco-sanctuaries. We review global examples of animal reintroductions taking place within areas modified by human activity, and, using information elicited from 18 experts, consider potential reintroduction candidates, and consider the benefits, opportunities, challenges, and requirements for the reintroduction of native species into New Zealand’s urban areas.

Leafy spurge (Euphorbia esula) Control and Soil Seedbank Composition Fifteen Years after Release of Aphthona Biological Control Agents

Aphthona spp. flea beetles were released in two ecological sites of the Little Missouri National Grasslands in southwestern North Dakota in 1999 to control leafy spurge. The change in leafy spurge density and soil seedbank composition was monitored to evaluate the effectiveness of the biological weed control agent and the associated change in plant communities 5, 10, and 15 yr after release in loamy overflow (valleys) and loamy sites (ridges). In 2014, 15 yr after release, leafy spurge stem density had decreased 94% from 110 to 7 stems m−2 in the loamy overflow sites and 88% from 78 to 9 stems m−2 in the loamy sites. Leafy spurge represented only 2% and 6% of the loamy overflow and loamy seedbanks in 2004, respectively, compared with nearly 67% and 70%, respectively, in 1999. There was a slow shift to reintroduction of native species into the seedbank over the last 15 yr. The number of desirable species increased to 21 by 2014 (more than three times the number of species in 1999) in the loamy overflow sites, and doubled to 14 species in the loamy sites, while less desirable forb species doubled in both sites. Desirable grass species doubled in the loamy overflow sites by 2014 but remained unchanged in loamy sites. Aphthona spp. successfully controlled leafy spurge for more than 15 yr without any additional control methods or costs to land managers and resulted in the slow return of a subset of native species.

The effect of soil inoculants on seed germination of native and invasive species

Successful reintroduction of native species through ecological restoration requires understanding the complex process of seed germination. Soil microbes play an important role in promoting native establishment and are often added to restoration sites during seed sowing. We tested the role of soil- and lab-grown bacterial inoculants on germination timing and percent germination for 19 species of plants commonly found in coastal California. Each species exhibited a different response to the inoculant treatments, but overall time-to-germination was longer and percent germination was lower with the soil inoculant compared with the control or other treatments. The invasive species in our study had the highest percent germination of all species and germinated faster than all native shrubs. Germination timing was negatively correlated with percent germination and with seed mass. Our results suggest that lab-grown inoculant and chemical treatment are effective at increasing germination in some native species, whereas soil inoculant is not. Given differences in germination timing between native and invasive species, restoration practitioners could consider using herbicide to treat areas seeded with native shrubs immediately following germination of invasive species without harming most natives, although germination timing and herbicides need further study in relation to microbial effects on seed germination.

Drivers of biodiversity patterns in parks of a growing South American megacity

How urban habitats contribute to biodiversity conservation is a key challenge in a rapidly urbanising world. Urban parks can provide important habitats for native species, but previous studies are geographically biased; fast growing megacities, in particular in South America, are clearly understudied. To assess habitat functions and underlying drivers in parks of Santiago de Chile, we analysed the assemblages of wild growing plant species in two ubiquitous park habitat types (grasslands, wooded areas) in 15 parks (150 plots) along an urban-rural gradient. We first used linear contrasts to compare species richness, beta diversity and the proportion of introduced species. We then tested for the explanatory value of environmental variables operating at different spatial scales (plot, park, urban matrix). Unlike in most previous studies, biodiversity patterns were not related to the position of the parks on the urban-rural gradient. Introduced species, mostly from Europe, generally dominated both habitat types (>90 %). Socio-economic (population growth or density), but not spatial, variables were retained in most models. Maintenance intensity was most influential in predicting species assemblages, complemented by park age in wooded areas. A high proportion of European grassland species indicates a trend of homogenisation in park grassland at a cross-continental scale. We conclude that habitat functions of urban parks for native species that have been mainly demonstrated for Europe cannot be generalised to South American megacities. This highlights the need for innovative and locally appropriate conservation approaches (e.g., re-introduction of native species) to foster biodiversity functions in urban parks of South American megacities.

Restoring forests: What constitutes success in the twenty-first century?

Forest loss and degradation is occurring at high rates but humankind is experiencing historical momentum that favors forest restoration. Approaches to restoration may follow various paradigms depending on stakeholder objectives, regional climate, or the degree of site degradation. The vast amount of land requiring restoration implies the need for spatial prioritization of restoration efforts according to cost-benefit analyses that include ecological risks. To design resistant and resilient ecosystems that can adapt to emerging circumstances, an adaptive management approach is needed. Global change, in particular, imparts a high degree of uncertainty about the future ecological and societal conditions of forest ecosystems to be restored, as well as their desired goods and services. We must also reconsider the suite of species incorporated into restoration with the aim of moving toward more stress resistant and competitive combinations in the longer term. Non-native species may serve an important role under some circumstances, e.g., to facilitate reintroduction of native species. Propagation and field establishment techniques must promote survival through seedling stress resistance and site preparation. An improved ability to generalize among plant functional groups in ecological niche adaptations will help to overcome site-limiting factors. The magnitude and velocity of ongoing global change necessitates rapid responses in genetics that cannot be naturally induced at valid temporal and spatial scales. The capacity for new concepts and technologies to be adopted by managers and accepted by society will depend on effective technology transfer and a community-based approach to forest restoration. The many benefits human society gains from forests requires that forest restoration considers multiple objectives and approaches to minimize trade-offs in achieving these objectives.

A priori assessment of reintroduction strategies for a native ungulate: using HexSim to guide release site selection

Reintroduction of native species to unoccupied portions of their historical range is a common management strategy to enhance the future viability of animal populations. This approach has met with mixed success, due to unforeseen impacts caused by human or other factors. Some of these impacts could potentially be mitigated through the use of anticipatory modeling coupled with appropriate management strategies prior to release. As part of an ongoing restoration program, we evaluated a portion of the former range of the tule elk (Cervus elaphus nannodes) in the Central Valley of California for potential reintroduction of a free-ranging herd. We used a new spatially explicit population model (HexSim) to analyze four different elk release scenarios. Each scenario corresponded to a different release location, and the model was used to compare simulated elk movement and population dynamics 25 years into the future. We also used HexSim to identify likely locations of human–elk conflict. Population forecasts after the 25-year period were highest (mean female population size of 169.6 per iteration) and potentially harmful barrier interactions were lowest (mean 8.6 per iteration) at the East Bear Creek site. These results indicate the East Bear Creek site release scenario as the most likely to result in a successful elk reintroduction, producing the most elk and generating the fewest human conflicts. We found HexSim to be a useful tool for this type of reintroduction planning and believe that other reintroduction efforts could benefit from this type of anticipatory modeling.

Seed longevity of 12 native herbaceous species in a fire-maintained pine savanna after 8 years of burial

Restoring the fire-maintained longleaf pine (Pinus palustris Mill.) ecosystem in the southeastern United States has become a regional conservation priority in recent years and development of cost-effective approaches to restoration is a major objective. An improved understanding of the potential role of persistent seed banks in the longleaf pine ecosystem and reliance on the seed bank for restoration efforts could contribute to reduced costs associated with restoration. We used a buried seed bag method to determine seed banking potential of species within three common families (Poaceae, Fabaceae, and Asteraceae) and a rare, endangered member of the Orobanchaceae family native to the longleaf pine ecosystem. Seeds were exhumed 1, 2, 4, and 8years after burial and tested for viability. Species within the Fabaceae showed the greatest potential for forming long-term persistent seed banks with seed viability 50% or greater after 8years of burial. Some species in the Poaceae, Asteraceae, and Orobanchaceae form transient or short-term persistent seeds banks. The ability of some species to form short- or long-term persistent seed banks may in some cases make it possible to rely on the seed bank for native species re-introductions on sites scheduled for restoration.

Diseases of poultry and endemic birds in Galapagos: implications for the reintroduction of native species

Reintroductions are increasingly utilized for the conservation of endangered avian species. To avert disease-related failures, studies to determine disease risks should be performed prior to the implementation of any avian reintroduction program. The presence, and prevalence, of disease-causing agents in both the source population and in birds at the site of reintroduction may help better direct reintroduction programs. In this study, we determined the prevalence of parasitic and pathogenic agents in chickens and wild birds on Floreana Island prior to the reintroduction of the critically endangered Floreana mockingbird Mimus trifasciatus. We investigated avian diseases on Floreana in 175 chickens and 274 wild birds. In addition to a number of clinical abnormalities, chickens tested positive for antibodies to paramyxovirus-1 (30%), adenovirus (11.3%) and seven other pathogens of concern for both domestic and wild birds. Wild birds on Floreana had antibodies to paramyxovirus-1 (3.0%) and adenovirus (2.4%). This is the first report of possible spillover of disease from domestic to wild birds in the archipelago. Based on these findings, and the lack of disease exposure documented in the source mockingbird population, we recommend improved poultry biosecurity measures on Floreana, and that mockingbirds only be reintroduced in areas on the island far from poultry and human presence and following further prerelease analyses. This study provides valuable data for the reintroduction of this iconic bird species and serves as a template for other avian reintroduction programs.

Rewilding – A New Paradigm for Nature Conservation in Scotland?

Rewilding is a strategy for the conservation of complete, self-sustaining ecosystems, primarily involving the protection and, where necessary, reintroduction, of populations of keystone species in large, connected reserve networks. A potential method of preserving ecosystem functions and biodiversity, it is now receiving a great deal of practical and political attention, particularly in North America. In Scotland, where many native species have been extirpated in the relatively recent past, rewilding has clear relevance and may provide an overarching set of objectives for current programmes of native woodland restoration and species reintroductions. Nevertheless, rewilding is not widely used as a term or strategy in Scottish conservation. This review considers the development of the concept and its possible application in Scotland, and identifies substantial scope for rewilding, in terms of the restoration and protection of large areas of wild land, and of the reintroduction of native species which have been driven to extinction by human activity. As the environmental, social and economic benefits which are likely to result from a programme of rewilding in Scotland outweigh the potential drawbacks, the adoption of rewilding is recommended as one aim of environmental policy.

Effects of Native Grass Restoration Management on Above- and Belowground Pasture Production and Forage Quality

Multifunctional agricultural landscapes and the ecosystem services they provide are gaining more attention. One example of this is the reintroduction of native species to cool-season grassland agroecosystems managed for livestock production. While such projects have potential ecological and agronomic benefits, there is little information on how restoration management affects pasture production and quality. The objective of this study was to determine how management to establish native warm-season grasses into temperate pastures affects forage production and quality. We tested this over three years (2004 through 2006) using a field experiment with combinations of disturbance (burning and grazing), soil amendments (ambient, nitrogen, and carbon), and native grass seeding times (fall and spring). We measured aboveground net primary production (ANPP), belowground net primary production (BNPP), and two forage quality parameters—neutral detergent fiber and in vitro neutral detergent fiber digestibility. For ANPP, there was a significant disturbance × soil amendment interaction effect in each year, but the nature of the interaction varied by year. In 2005, plots where nitrogen was applied had lower BNPP than carbon and ambient plots. In 2006, burned plots had greater BNPP than grazed plots. For each level of disturbance, over 50% of the variability in the forage quality parameters was attributed to non-management variables, such as season. Our results showed no consistent effect of restoration management on pasture production or quality. They highlight the complexity of grassland agroecosystems and demonstrate the importance of evaluating the variability of treatment effects over time.

Temperature Effects on Interspecific Interference among Two Native Wetland Grasses and Tall Fescue

Successful reintroduction of native species into landscapes requires an understanding of how introduced species invaded and became established. This study was conducted to determine the effect of temperature on interspecific seedling interference of two wetland grasses [sloughgrass (Beckmannia syzigachne Steud.) and tufted hairgrass (Deschampsia caespitosa L.)] native to the Pacific Northwest and tall fescue (Festuca arundinaceae Schreb. cv. Titan), a non‐native grass species. The relationships of species interference to the thermal response of Photosystem II (PS II) fluorescence reappearance ratio (FRR) and glutathione reductase (GR) thermal stability were also investigated using the Mantel product moment correlation (rm). Three combinations of two‐species replacement series experiments (sloughgrass–hairgrass mixture, sloughgrass–tall fescue mixture, and hairgrass–tall fescue mixture) were conduced in growth chambers, planted in five proportions (0.0:1.0, 0.25:0.75, 0.5:0.5, 0.75:0.25, and 1.0:0.0), and grown at four temperatures (5, 10, 20, and 30°C). The FRR and GR were measured at eight temperatures ranging from 5 to 40°C. Tall fescue aggressiveness, relative to sloughgrass and hairgrass, increased with increasing temperature. Sloughgrass and hairgrass ranked second and third, respectively, and were only more aggressive than tall fescue at 5°C. Peak FRR occurred at 15, 20, and 22.5°C for sloughgrass, hairgrass, and tall fescue, respectively. Seedling dry mass of species was correlated with the stability of GR and the average efficiency of the PS II apparatus over the range of growing temperatures (rm = −1.00 and 0.96, respectively). Tall fescue had greater PS II efficiency and GR stability under elevated temperatures than sloughgrass and hairgrass, which may explain why tall fescue has been able to dominate some wetland landscapes of the temperate Pacific Northwest.