Planning Conservation Strategies Research Articles

Habitat Selection by Alpine Rock PtarmiganLagopus muta helveticain the Italian Alps

We analysed space use strategies in two populations of Alpine Rock Ptarmigan Lagopus muta helvetica considering three topographical variables (elevation, slope and aspect) to investigate whether populations living at range margins can adapt to suboptimal conditions by exploiting the available habitat differently. Selection for topographic features differed between populations, suggesting that Rock Ptarmigan adapt their habitat selection to local availability. Therefore, we suggest considering a wide range of habitat parameters when planning conservation strategies for species living at the margins of their range.

Simplified large African carnivore density estimators from track indices.

BackgroundThe range, population size and trend of large carnivores are important parameters to assess their status globally and to plan conservation strategies. One can use linear models to assess population size and trends of large carnivores from track-based surveys on suitable substrates. The conventional approach of a linear model with intercept may not intercept at zero, but may fit the data better than linear model through the origin. We assess whether a linear regression through the origin is more appropriate than a linear regression with intercept to model large African carnivore densities and track indices.MethodsWe did simple linear regression with intercept analysis and simple linear regression through the origin and used the confidence interval for ß in the linear model y = αx + ß, Standard Error of Estimate, Mean Squares Residual and Akaike Information Criteria to evaluate the models.ResultsThe Lion on Clay and Low Density on Sand models with intercept were not significant (P > 0.05). The other four models with intercept and the six models thorough origin were all significant (P < 0.05). The models using linear regression with intercept all included zero in the confidence interval for ß and the null hypothesis that ß = 0 could not be rejected. All models showed that the linear model through the origin provided a better fit than the linear model with intercept, as indicated by the Standard Error of Estimate and Mean Square Residuals. Akaike Information Criteria showed that linear models through the origin were better and that none of the linear models with intercept had substantial support.DiscussionOur results showed that linear regression through the origin is justified over the more typical linear regression with intercept for all models we tested. A general model can be used to estimate large carnivore densities from track densities across species and study areas. The formula observed track density = 3.26 × carnivore density can be used to estimate densities of large African carnivores using track counts on sandy substrates in areas where carnivore densities are 0.27 carnivores/100 km2 or higher. To improve the current models, we need independent data to validate the models and data to test for non-linear relationship between track indices and true density at low densities.

Forest mammal roadkills as related to habitat connectivity in protected areas

Fragmentation of wildlife habitat by road development is a major threat to biodiversity. Hence, conservation and enhancement of habitat connectivity in roaded landscapes are crucial for effectively maintaining long-term persistence of ecological processes, such as gene flow and migration. Using multivariate statistical techniques combined with graph theoretical methods, we investigated the influence of road-crossing habitat connectivity and road-related features on roadkill abundance of forest mammals in protected areas of South Korea. Because species have different dispersal abilities and thus connectivity would differ between them, we explored three different groups of road-killed mammals, categorized as small, intermediate, and large ones. We found that in all three mammal groups, roadkills are increased on roads that intersect high-connectivity routes. Furthermore, the effect of habitat connectivity on roadkill abundance was scale-dependent. The roadkill abundances of small, intermediate, and large mammals were related with connectivity measured at scales ranging between 100 and 300 m, between 5 and 7 km, and between 10 and 25 km, respectively. Our finding with regard to scale-dependency highlights the importance of maintaining movement and connectivity across roads at multiple scales based on the dispersal potential of different species when planning conservation strategies for forest mammalian roadkill mitigation.

Butterflies of the Rice Research Station and adjoining locality in Chinsurah, West Bengal, India

Chinsurah is a small town on the western bank of the Hugli River, a distributary of the river Ganges. A survey from November 2006 to June 2014 with photographic documentation on the butterfly community in Chinsurah revealed the presence of a total of 70 species representing 53 genera in five families; most dominant family was the Nymphalidae having 34.3% of the total species. Six species are legally protected; one species under Schedule I; three species under Schedule II; and two species under Schedule IV of the Indian Wildlife (Protection) Act, 1972. Rare species like Pareronia avator (Moore), Mahathala ameria (Hewitson) and Melanitis zitenius (Herbst) were recorded in this rapidly degrading habitat. This study may help in planning conservation strategies in urban areas and sustainable development as well.

Geospatial approaches to support pelagic conservation planning and adaptive management

Place-based management in the open ocean faces unique challenges in delineating boundaries around temporally and spatially dynamic systems that span broad geographic scales and multiple management jurisdictions, especially in the ‘high seas’. Geospatial technologies are critical for the successful design of pelagic conservation areas, because they provide information on the spatially and temporally dynamic oceanographic features responsible for driving species distribution and abundance in the open ocean, the movements of protected species, and the spatial patterns of distribution of potential threats. Nevertheless, there are major challenges to implementing these geospatial approaches in the open ocean. This Theme Section seeks to bridge the gap between geospatial science and marine conservation by discussing the use of innovative approaches to support effective marine conservation planning strategies for pelagic ecosystems. We highlight the results of this collection of contributions in 3 main sections: (1) conceptual advances in pelagic conservation; (2) novel information technologies and methodologies; and (3) case studies in the California Current and Pacific Ocean.

The Challenge of Planning Conservation Strategies in Threatened Seascapes: Understanding the Role of Fine Scale Assessments of Community Response to Cumulative Human Pressures.

Assessing the distribution and intensity of human threats to biodiversity is a prerequisite for effective spatial planning, harmonizing conservation purposes with sustainable development. In the Mediterranean Sea, the management of Marine Protected Areas (MPAs) is rarely based on explicit consideration of the distribution of multiple stressors, with direct assessment of their effects on ecosystems. This gap limits the effectiveness of protection and is conducive to conflicts among stakeholders. Here, a fine scale assessment of the potential effects of different combinations of stressors (both land- and marine-based) on vulnerable rocky habitats (i.e. lower midlittoral and shallow infralittoral) along 40 km of coast in the western Mediterranean (Ionian Sea) has been carried out. The study area is a paradigmatic example of socio-ecological interactions, where several human uses and conservation measures collide. Significant differences in the structure of assemblages according to different combinations of threats were observed, indicating distinct responses of marine habitats to different sets of human pressures. A more complex three-dimensional structure, higher taxon richness and β-diversity characterized assemblages subject to low versus high levels of human pressure, consistently across habitats. In addition, the main drivers of change were: closeness to the harbour, water quality, and the relative extension of beaches. Our findings suggest that, although efforts to assess cumulative impacts at large scale may help in individuating priority areas for conservation purposes, the fact that such evaluations are often based on expert opinions and not on actual studies limits their ability to represent real environmental conditions at local scale. Systematic evaluations of local scale effects of anthropogenic drivers of change on biological communities should complement broad scale management strategies to achieve effective sustainability of human exploitation of marine resources.

Limited prospecting behaviour of juvenile Eagle Owls Bubo bubo during natal dispersal: implications for conservation

Capsule Features of the breeding population and temporary settlement area influence the behaviour of Eagle Owls Bubo bubo prospecting for breeding sites during natal dispersal.Aims To understand how prospecting behaviour during natal dispersal is affected by (i) the main characteristics of the breeding and dispersing portions of the population and (ii) main prey availability.Methods We explored the ten-year dynamics and characteristics of radio-tagged breeders and dispersers of an Eagle Owl population.Results During the first years following natal dispersal there was little prospecting behaviour of nesting sites and birds remained mainly within non-breeding settlement areas, bordering the sector occupied by the breeding population. Settlement areas had an abundant food supply, and low intraspecific competition and mortality. We suggest that these features of the settlement areas may reduce the willingness of individuals to search for breeding sites and may have the potential to impact on the viability of breeding populations.Conclusion From a conservation perspective, the lengthy use of the temporary settlement areas by juvenile Eagle Owls suggests that the sites should be considered as important as the breeding areas when planning conservation strategies. Reducing juvenile mortality in settlement areas may represent an overlooked conservation strategy for long-lived species and may have a crucial effect on the viability some animal populations.

Multilocus coalescent species delimitation reveals widespread cryptic differentiation among Drakensberg mountain-living freshwater crabs (Decapoda : Potamonautes)

Cryptic lineages present major challenges for evolutionary and conservation studies, particularly where these lineages remain undiscovered. Freshwater crabs are known to harbour cryptic diversity, in most cases with limited morphological differences. During the present study, we used a multilocus (12S rRNA, 16S rRNA, COI, 28S rRNA, DecapANT and PEPCK) Bayesian species delimitation to examine cryptic diversity within a freshwater crab species complex (Potamonautes clarus/P. depressus). We sampled 25 highland rivers in the Tugela and uMkomazi River drainage systems of the Drakensberg Mountain range, in the KwaZulu–Natal province of South Africa. Our results showed there to be at least eight lineages: six novel potamonautid freshwater crabs, and two described taxa P. clarus and P. depressus. Divergence from the most recent common ancestor occurred between the mid- and late Miocene (12.1 Mya), while divergence within the species complex occurred ~10.3 Mya up until the Holocene (0.11 Mya). The discovery of six novel lineages of freshwater crabs from a seemingly restricted distribution range has conservation implications, but to date most conservation planning strategies have focussed on freshwater vertebrates. By conducting a fine-scale phylogenetic survey using invertebrates, this study provides a platform for the inclusion of freshwater invertebrates in future conservation assessments.

Responses of Vegetation to Temperature Gradients around Geothermal Features: A Review on Wairakei -Tauhara Geothermal Field, Taupo, New Zealand

Geothermal ecosystems experience extreme conditions but can support unique communities of organisms. This study uses historical thermal infrared images and aerial photographs to review the vegetation responses to temperature gradients around geothermal surface features in the Wairakei-Tauhara geothermal field. Here, the spatial distribution of ‘‘geothermal kanuka’’, Kunzea tenuicaulis and related species and hybrids is mapped in relation to ground temperatures measured from the thermal infrared images. Optimal growing conditions for these plant communities in the geothermal area were at ground temperatures higher than ambient. Areas of moderate to high surface heat continued to support plant communities but as ground surface temperature reduced, vegetation growth and establishment increased. The results presented here demonstrate the impact of surface temperature on vegetation and suggest that long-term temperature intensification or reduction over an area does not wipe out vegetation completely. In this case, geothermal kanuka was able to adapt to changes in the temperature and increase its distributing. Understanding how these plants survive in high-temperature ecosystems may provide insight into how they cope with changes in temperature in these and other extreme habitats and how other species may respond to future climate change. An awareness of the interactions between temperature and plant community structure can help plan conservation strategies for the future.

Interacting Social and Environmental Predictors for the Spatial Distribution of Conservation Lands.

Conservation decisions should be evaluated for how they meet conservation goals at multiple spatial extents. Conservation easements are land use decisions resulting from a combination of social and environmental conditions. An emerging area of research is the evaluation of spatial distribution of easements and their spatial correlates. We tested the relative influence of interacting social and environmental variables on the spatial distribution of conservation easements by ownership category and conservation status. For the Appalachian region of the United States, an area with a long history of human occupation and complex land uses including public-private conservation, we found that settlement, economic, topographic, and environmental data associated with spatial distribution of easements (N = 4813). Compared to random locations, easements were more likely to be found in lower elevations, in areas of greater agricultural productivity, farther from public protected areas, and nearer other human features. Analysis of ownership and conservation status revealed sources of variation, with important differences between local and state government ownerships relative to non-governmental organizations (NGOs), and among U.S. Geological Survey (USGS) GAP program status levels. NGOs were more likely to have easements nearer protected areas, and higher conservation status, while local governments held easements closer to settlement, and on lands of greater agricultural potential. Logistic interactions revealed environmental variables having effects modified by social correlates, and the strongest predictors overall were social (distance to urban area, median household income, housing density, distance to land trust office). Spatial distribution of conservation lands may be affected by geographic area of influence of conservation groups, suggesting that multi-scale conservation planning strategies may be necessary to satisfy local and regional needs for reserve networks. Our results support previous findings and provide an ecoregion-scale view that conservation easements may provide, at local scales, conservation functions on productive, more developable lands. Conservation easements may complement functions of public protected areas but more research should examine relative landscape-level ecological functions of both forms of protection.

Estimating and mapping forest structural diversity using airborne laser scanning data

Abstract Among the wide array of terrestrial habitats, forest and wooded lands are the richest from both biological and genetic points of view because of their inherent structural and compositional complexity and diversity. Although species composition is an important biodiversity feature, forest structure may be even more relevant for biodiversity assessments because a diversified structure is likely to have more niches, which in turn, host more species and contribute to a more efficient use of available resources. Structure plays a major role as a diversity indicator for management purposes where maps of forest structural diversity are of great utility when planning conservation strategies. Airborne laser scanning (ALS) data have been demonstrated to be a reliable and valid source of information for describing the three-dimensional structure of forests. Using ALS metrics as predictor variables, we developed regression models for predicting indices of forest structural diversity for a study area in Molise, Italy. The study had two primary objectives: (i) to estimate indices of structural diversity for the entire study area, and (ii) to construct maps depicting the spatial pattern of the structural diversity indices. Our results demonstrate the utility of simple linear models using ALS data for improving areal estimates of mean structural diversity, and the resulting maps capture the patterns of structural diversity in the study area.

Testing projected wild bee distributions in agricultural habitats: predictive power depends on species traits and habitat type.

Species distribution models (SDM) are increasingly used to understand the factors that regulate variation in biodiversity patterns and to help plan conservation strategies. However, these models are rarely validated with independently collected data and it is unclear whether SDM performance is maintained across distinct habitats and for species with different functional traits. Highly mobile species, such as bees, can be particularly challenging to model. Here, we use independent sets of occurrence data collected systematically in several agricultural habitats to test how the predictive performance of SDMs for wild bee species depends on species traits, habitat type, and sampling technique. We used a species distribution modeling approach parametrized for the Netherlands, with presence records from 1990 to 2010 for 193 Dutch wild bees. For each species, we built a Maxent model based on 13 climate and landscape variables. We tested the predictive performance of the SDMs with independent datasets collected from orchards and arable fields across the Netherlands from 2010 to 2013, using transect surveys or pan traps. Model predictive performance depended on species traits and habitat type. Occurrence of bee species specialized in habitat and diet was better predicted than generalist bees. Predictions of habitat suitability were also more precise for habitats that are temporally more stable (orchards) than for habitats that suffer regular alterations (arable), particularly for small, solitary bees. As a conservation tool, SDMs are best suited to modeling rarer, specialist species than more generalist and will work best in long-term stable habitats. The variability of complex, short-term habitats is difficult to capture in such models and historical land use generally has low thematic resolution. To improve SDMs' usefulness, models require explanatory variables and collection data that include detailed landscape characteristics, for example, variability of crops and flower availability. Additionally, testing SDMs with field surveys should involve multiple collection techniques.

Strategies for conservation planning and management of terrestrial ecosystems in small islands (exemplified for the Macaronesian islands)

The present paper addresses the conservation planning and management issues of terrestrial ecosystems with particular insight to small islands (with examples of application in the Macaronesian archipelagos of Cape Verde, Canaries, Madeira and Azores). It analyses specific conservation planning and management approaches and proposes concrete characterization and evaluation frameworks able to support decision and management processes ensuring an active and participative involvement of all concerned stakeholders. These methodological perspectives involve not only new paradigmatic approaches to the process of characterization and evaluation of environmental elements and processes as well as their use and disturbance through land use, but also regarding the individual and collective perspectives regarding benefice and supporting management behaviours. Some examples from islands of the Macaronesian archipelagos, in particular Pico in the archipelago of Azores and Santiago in the Cape Verde archipelago, are used to illustrate some possible management approaches, involving the consideration of the entire island as a conservation object and mobilizing their actors (individuals, groups, administrations or other organizations) as conscious, participative stakeholders. These examples involve possible land use and management changes and trade-off processes specific to each island that are listed and explained.

Highlighting the effects of land‐use change on a threatened amphibian in a human‐dominated landscape

AbstractIn Western Europe, habitat loss and landscape fragmentation has led to significant population decline in various animal groups, including amphibians. The extinction of the last natural populations of the yellow‐bellied toad in Belgium, Luxembourg and several regions of southern and western France suggests a widespread decline. By using site‐occupancy models and adding covariates corresponding to the human‐influenced features of the landscape, we tried to identify the relative effects of different land‐use types on the species’ distribution pattern in a man‐made environment (the Alsatian Rhine floodplain in France). We recorded presence–absence data in 150 forest sample plots (300 × 300 m) and then modeled species distribution while taking into account detection errors in the field. Land‐use was recorded on two spatial scales: within the forest sample plots and in a 1500 m radius buffer area around the forest plots. In the forest plots, toad occurrence was negatively correlated with loss of forest cover to agricultural land. In contrast, occurrence is positively correlated with the density of human‐made rutted dirt paths and tracks, which provide semi‐natural breeding sites. In the 1500 m radius buffer zones around forest plots, toad occurrence was negatively correlated with the density of urbanization and road networks. These results can be used to plan conservation strategies for amphibians in human‐dominated landscapes.

Impacts of anthropogenic land-use change on populations of the Endangered Patagonian cypress Fitzroya cupressoides in southern Chile: implications for its conservation

AbstractLand-use change can have negative effects on threatened species by modifying their habitat and population dynamics. The habitat of the Endangered Patagonian cypress Fitzroya cupressoides (Mol.) Johnst. (Cupressaceae), a conifer endemic to the temperate forests of southern Chile and Argentina, has been transformed by land-use change and overexploitation. The impact of land-use change on the spatial pattern of F. cupressoides habitat from 1999 to 2011 was evaluated at the landscape level, using satellite images. Additionally, eight 20 × 25 m plots were established in four populations to assess their status. In each plot the density of F. cupressoides and the species richness of the associated plant communities were recorded and analysed, together with spatial patterns at the population and community levels. The loss of potential F. cupressoides habitat was 46% from 1999 to 2011 (38–100% for the four populations). The density of F. cupressoides was lowest in smaller habitat patches, where the number of plant species was higher and the matrix dominated by anthropogenic land-use. Land-use change was associated with a loss of potential habitat for F. cupressoides, and differences in the spatial patterns of habitat influenced the composition of remaining populations and communities. A landscape approach is recommended as a conservation planning strategy for F. cupressoides.

Morphological analysis of green infrastructure in the Seoul metropolitan area, South Korea

The purpose of this study is to understand changes in green infrastructure (GI) in the Seoul metropolitan area, South Korea, focusing on the critical GI components of hubs and links. We applied a morphological analysis tool, morphological spatial pattern analysis (MSPA), to explore GI in the Seoul metropolitan area. For input data to run MSPA, we used 30-m pixel-sized land cover data of 2000 and 2009 provided by the Ministry of Environment of Korea. Land cover data are used as foundational information for GI network mapping. Using MSPA, we examined morphological changes in hubs and links from 2000 to 2009 in the metropolitan area as well as in 32 municipalities in Gyeonggi-do, a major part of the metropolitan area. Our analysis showed that the area of hubs in the Seoul metropolis has decreased, while the number of links has dramatically increased, over this 10-year period. This implies that hubs have largely been fragmented into smaller ones with a rapid increase in links in a way that does not conserve and enhance GI. We also compared analysis of network area changes in the Seoul metropolitan area with the environmental conservation value assessment map (ECVAM) currently in use by the government to assess conservation value, and found that the network areas of 2009 mapped by MSPA corresponded to a 87.8 % level to the Grade I areas of the ECVAM, with variation by municipality. From these analyses, we conclude that MSPA is helpful in establishing conservation planning strategies optimized for local and regional contexts. The MSPA also provides a useful tool to complement the ECVAM for improving GI functions.

Simulating urbanization scenarios reveals tradeoffs between conservation planning strategies

Land that is of great value for conservation can also be highly suitable for human use, resulting in competition between urban development and the protection of natural resources. To assess the effectiveness of proposed regional land conservation strategies in the context of rapid urbanization, we measured the impacts of simulated development patterns on two distinct conservation goals: protecting priority natural resources and limiting landscape fragmentation. Using a stochastic, patch-based land change model (FUTURES) we projected urbanization in the North Carolina Piedmont according to status quo trends and several conservation-planning strategies, including constraints on the spatial distribution of development, encouraging infill, and increasing development density. This approach allows simulation of population-driven land consumption without excluding the possibility of development, even in areas of high conservation value. We found that if current trends continue, new development will consume 11% of priority resource lands, 21% of forested land, and 14% of farmlands regionally by 2032. We also found that no single conservation strategy was optimal for achieving both conservation goals. For example, strategies that excluded development from priority areas caused increased fragmentation of forests and farmlands, while infill strategies increased loss of priority resources proximal to urban areas. Exploration of these land change scenarios not only confirmed that a failure to act is likely to result in irreconcilable losses to a conservation network, but that all conservation plans are not equivalent in effect, highlighting the importance of analyzing tradeoffs between alternative conservation planning approaches.

Sex pheromones as a tool to overcome the Wallacean shortfall in conservation biology: a case of Elater ferrugineus Linnaeus, 1758 (Coleoptera: Elateridae)

The “Wallacean shortfall”—lack of distributional information—is one of the main problems when trying to assess the threats to and planning conservation strategies for many invertebrate species. Based on published and unpublished records since 1840, as well as on our own field survey, we attempted to estimate if and to what extent the use of pheromone traps increased the detectability of a rare, saproxylic click beetle Elater ferrugineus. The significant increase in the number of records in 2011–2013 shows that the pheromone method made it much easier to detect the occurrence of the species. Advantages of the pheromone method are that it does not disturb the habitat, can be used by non-specialists, is less costly and less time-consuming, and thus providing a useful tool for conservation research (studying biology, ecology and genetics of local populations).

Bayesian estimates of transition probabilities in seven small lithophytic orchid populations: maximizing data availability from many small samples.

Predicting population dynamics for rare species is of paramount importance in order to evaluate the likelihood of extinction and planning conservation strategies. However, evaluating and predicting population viability can be hindered from a lack of data. Rare species frequently have small populations, so estimates of vital rates are often very uncertain due to lack of data. We evaluated the vital rates of seven small populations from two watersheds with varying light environment of a common epiphytic orchid using Bayesian methods of parameter estimation. From the Lefkovitch matrices we predicted the deterministic population growth rates, elasticities, stable stage distributions and the credible intervals of the statistics. Populations were surveyed on a monthly basis between 18–34 months. In some of the populations few or no transitions in some of the vital rates were observed throughout the sampling period, however, we were able to predict the most likely vital rates using a Bayesian model that incorporated the transitions rates from the other populations. Asymptotic population growth rate varied among the seven orchid populations. There was little difference in population growth rate among watersheds even though it was expected because of physical differences as a result of differing canopy cover and watershed width. Elasticity analyses of Lepanthes rupestris suggest that growth rate is more sensitive to survival followed by growth, shrinking and the reproductive rates. The Bayesian approach helped to estimate transition probabilities that were uncommon or variable in some populations. Moreover, it increased the precision of the parameter estimates as compared to traditional approaches.

Predation selectively culls medium-sized species from island mammal faunas.

Globally, elevated extinction risk in mammals is strongly associated with large body size. However, in regions where introduced predators exert strong top-down pressure on mammal populations, the selectivity of extinctions may be skewed towards species of intermediate body size, leading to a hump-shaped relationship between size and extinction risk. The existence of this kind of extinction pattern, and its link to predation, has been contentious and difficult to demonstrate. Here, we test the hypothesis of a hump-shaped body size-extinction relationship, using a database of 927 island mammal populations. We show that the size-selectivity of extinctions on many islands has exceeded that expected under null models. On islands with introduced predators, extinctions are biased towards intermediate body sizes, but this bias does not occur on islands without predators. Hence, on islands with a large-bodied mammal fauna, predators are selectively culling species from the lower end of the size distribution, and on islands with a small-bodied fauna they are culling species from the upper end. These findings suggest that it will be difficult to use predictable generalizations about extinction patterns, such as a positive body size-extinction risk association, to anticipate future species declines and plan conservation strategies accordingly.