Remnant Native Vegetation Research Articles

Movements of adult and fledgling Carnaby’s Cockatoos (Zanda latirostris Carnaby, 1948) from eleven breeding areas throughout their range

Context Carnaby’s Cockatoo is an endangered species and the subject of a recovery plan. Aims Our study examined movements of adult and fledgling Carnaby’s Cockatoos from 11 breeding populations in southwestern Australia to establish where the cockatoos spent the non-breeding season (February–May) and sub-adult life-stage. Methods Data were collected on point-to-point movements from re-sightings and recoveries of cockatoos individually marked with patagial tags or leg bands. Sites were mostly located in the wheatbelt of Western Australia. Distribution patterns in the breeding and non-breeding seasons, including nesting sites were derived from location data from the Department of Biodiversity, Conservation and Attractions’ Threatened and Priority Database. Key results After breeding, adults and their fledglings moved from breeding areas to higher rainfall areas closer to the west and south coasts of south-western Australia where the food supply is greater and more reliable. Sub-adult cockatoos roam much more widely than adults and utilize foraging habitat not previously recognized as being important to this species. Conclusions Important foraging habitat and locations have been identified for breeding populations in the north and south of the range of Carnaby’s Cockatoos. Implications More conservation attention needs to be focussed on locating additional breeding populations, assessing the viability of these populations, and the extent and condition of their nesting and foraging habitat used during their non-breeding season. Conservation of Carnaby’s Cockatoo depends on the maintenance of remnant native vegetation and revegetation of nesting and foraging habitat throughout its range.

Comparison of thermal cameras and human observers to estimate population density of fallow deer (Dama dama) from aerial surveys in Tasmania, Australia

Context The population of introduced fallow deer (Dama dama) is thought to have increased exponentially across much of the island of Tasmania, Australia, since 2000. Historically, deer management decisions have relied on population trend data from vehicular spotlight surveys. Renewed focus on the contemporary management of the species requires development of more robust and precise population estimation methodology. Aims This study demonstrates two aerial survey methods – conventional counts by trained human observers, and thermal imaging footage recorded during the same flights – to inform future survey practices. Methods Conventional counts were carried out by three observers, two seated on the left side of the helicopter, and one on the right. A high-resolution thermal camera was fitted to the helicopter and was orientated to meet the assumptions of distance sampling methodologies. Both survey methods were used to generate deer population density estimates. Spatial distribution of deer was also analysed in relation to patches of remnant native vegetation across an agricultural landscape. Mark–recapture distance sampling was used to estimate density from human observer counts and provide a comparison to the distance sampling estimates derived from the thermal camera. Key results Human observer counts gave a density estimate of 2.7 deer per km2, while thermal camera counts provided an estimate of 2.8 deer per km2. Deer population density estimates calculated via both methods were similar, but variability of the thermal camera estimate (coefficient of variation (CV) of 36%) was unacceptably high. Human observer data was within acceptable bounds of variability (CV, 19%). The estimated population size in central and north-eastern Tasmania for 2019 approximated 53,000 deer. Deer were primarily congregated within 200 metres of the interface between canopy cover and open pasture. Conclusions The population density estimate provides a baseline for monitoring and managing the Tasmanian deer population. Human observer data was more precise than thermal camera data in this study, but thermal counts could be improved by reducing sources of variability. Implications Improvements for the collection of thermal imagery are recommended. Future control efforts may be more efficient if they preferentially target habitat edges at this time of year, paired with random or grid-based searches where population density is lower.

Using spatial parameters to assess pesticides as a plausible threat to fauna

The impact of pesticides on fauna remains a little-known topic. In Europe and North America, the belief that insecticide use may be partially linked to populational declines in pollinating insects is one based on fragments of evidence. Classifying pesticides as a biodiversity threat might therefore be more reliant on the perceived interactions between species and sprayed crops. Brazil’s high pesticide use and rich biodiversity provide an opportunity to assess whether spatial parameters can be used to infer the potential biodiversity threat of pesticides by mapping the risk of exposure faced by 100 animal species considered threatened by these chemical agents. A given specie’s risk of exposure is the proportion of its potential distribution that overlaps with agricultural areas utilizing pesticides relative to the area of remnant natural vegetation. When these parameters were applied, results show that only 16 % of those species in Brazil considered threatened by pesticides had a high risk of exposure. This article argues that citing pesticides as a specie’s threat based only on assumptions confuses the understanding of a link that is already difficult to verify. Spatial parameters such as risk of exposure offer a more objective approach to assess the threat plausibility pesticides pose to fauna and can reveal other overlooked species possessing higher potential from being impacted by these chemical agents.

Unveiling the complex networks of urban tree diversity research: A global perspective.

Ecosystem services offered by urban forests must be proactively managed to remain diverse and sustainable. Recent research findings deserve a systematic synthesis to elucidate inherent knowledge structures and dynamics. This study focused on the urban tree diversity theme from 2000 to 2022. Web of Science Core Collection database provided bibliometric details on academic publications. The data-driven quantitative analysis explored research quantities, emphasis, trends, patterns, linkages, and impacts by countries, institutions, authors, journals, and citations. Publications and research topics have expanded continually, with accelerated growth in recent years. Research activities, outputs and interactions demonstrated conspicuous spatial clustering. A few countries, institutions and researchers generated a notable proportion of publications. Their scholarly contributions were visualized in knowledge graphs as complex networks of nodes and inter-node links. Keyword analysis generated a network to indicate research hotspots and frontiers to steer and prioritize future studies. Recent findings affirmed that cities can harbor substantial tree diversity due to enhanced habitat heterogeneity and successful species adaptation. Aligning tree traits with environmental conditions and management objectives can improve benefits. Urbanization can filter tree traits to shape community assemblages through stressors: habitat degradation, fragmentation and loss, in conjunction with pollution, climate change, and introduced species. Diversity preservation strategies include protecting remnant natural vegetation, connecting green spaces, and restoring complex canopy geometry and biomass structure. The emerging frontiers are marked by modeling future species distributions, leveraging technologies like remote sensing, linking ecology with human values, and committing to community-based stewardship. Management can be upgraded by interdisciplinary perspectives integrating ecological science and social engagement. The findings highlight the need for biodiversity enrichment anchored by native species, trait-matched assemblages, adaptive policies, and community participation to create livable-green cities. This review synthesizes key advances in urban tree ecology and biodiversity research to inform the planning and stewardship of resilient urban forests.

The aesthetic value of natural vegetation remnants, city parks and vacant lots: The role of ecosystem features and observer characteristics

Physical and mental well-being are linked to exposure to ecosystems perceived as aesthetically pleasing. However, the perceived aesthetic value is shaped by both ecosystem features and observer characteristics. This study explores the relationships between these two influential factors, and perceptions across three Canadian urban greenspace types: natural vegetation remnants (forest stands, marshes and peatlands), city parks, and vacant lots. We administered an online photo-questionnaire, completed by 514 respondents, who assessed the beauty of 45 greenspaces on a five-point Likert scale. Respondents were university students and staff, members of the general public, and specialists in ecosystem services. They also answered questions on socio-demographic factors, pro-environmental attitudes, nature-related travel habits, and ecological knowledge. We calculated five variables from each greenspace photo: vegetation structural complexity, visual complexity, percentage of green pixels, percentage of canopy cover, and presence/absence of artificial structures. On average, natural vegetation remnants and city parks were preferred over vacant lots. Among natural remnants, forests were preferred over semi-open peatlands. Different ecosystem features were associated with perceived beauty across the three greenspace types. For natural remnants and city parks, visual complexity was positively related to appreciation scores, whereas for vacant lots, the presence of artificial structures was associated with lower appreciation scores. Respondents who self-identified as environmental defenders, had greater knowledge of flora, and travelled to observe fauna gave higher appreciation scores to vacant lots compared to other respondents. Younger respondents, and those who engaged in frequent nature-related travelling attributed higher scores to natural remnants. We conclude that aesthetic preferences for natural vegetation remnants, city parks, and vacant lots are influenced by a complex interplay of ecosystem features and observer characteristics. Understanding these intricate relationships can guide the management of vacant lots and promote more inclusive engagement with greenspaces, by considering the varying preferences of diverse segments of the population.

Detection and monitoring of the fauna of medium and large mammals using camera traps in a forest remnant area in the municipality of Água Fria de Goiás, Brazil – A tool for nature conservation

Despite the growing amount of information available, biodiversity is still under threat. Wildlife plays a crucial role in maintaining the ecological balance, and it is of logical and strategic importance to promote the further development of fauna recording and monitoring processes, emphasizing the need to strengthen the relationship between humans and nature. The aim was to record the species of medium and large mammals using camera traps. The study was conducted in the EcoCerrado Reserve in the municipality of Água Fria de Goiás, Brazil, between December 2020 and December 2022, using two camera traps in three different phytophysiognomies. 17 mammal species were recorded in 149 camera trap records, including species in the threatened category, such as Myrmecophaga tridactyla, Tapirus terrestrials, Chrysocyon brachyurus, Lycalopex vetulus, Panthera onca and Alouatta caraya. The mammal fauna observed in the study shows that this ecosystem can support populations of native species even in a modified landscape. This finding strengthens the basis for future initiatives aimed at environmental education, ecotourism, and more comprehensive legal protection for this region and other remnants of native vegetation in the Cerrado.

Floral abundance and corolla length predict the importance of species in connecting urban green areas

Despite the growing urbanization rate and its consequences on biodiversity and species interactions worldwide, the connection among urban green areas, performed by interacting species, is still poorly understood. We evaluated how plant and hummingbird species vary across the urban landscape of a tropical city in Brazil, identifying traits of species taking part in shared interactions between areas. We recorded plant-hummingbird interactions in five green spaces and two remnants of native vegetation, and: (1) contrasted species traits and species-level indices of both plants and hummingbirds; (2) evaluated how species and interactions vary among pairs of areas; (3) used a meta-network approach to identify which pairs of interacting species are more important in connecting areas. Species turnover was the component that better explained the beta-diversity of interactions among sites. In green spaces, plant species presented greater centrality and longer corollas than in remnants. However, both plants and hummingbirds were similarly specialized regardless of the type of area. Trees with large floral displays and with longer corollas shared more interactions and were present in more networks. Most interactions recorded in remnants are unique to them, due to the exclusiveness of some hummingbirds and plant species in such native habitat and are, thus, more sensitive to habitat conversion. Our findings support the importance of preserving remnants and using mass flowering native species in urban afforestation to maintain plant-hummingbird interactions and promote urban biodiversity. We evidenced that few interactions (16.6%) were redundant across areas, indicating a highly susceptible and fragmented system in the urban space.

CONNECTIVITY OF THE HABITAT OF TAPIRUS TERRESTRIS (LINNAEUS, 1758) IN THE MATA DOS GODOY STATE PARK AND ITS BUFFER ZONE

This study aimed to assess the functional connectivity of Mata dos Godoy State Park (PEMG) and its buffer zone (ZA), covering an area of 38,950.45 hectares, spanning parts of the municipalities of Londrina, Arapongas, and Apucarana. The objective was to identify forest patches with enhanced connective capacity among themselves, which are utilized by Tapirus terrestris. The land use and land cover shapefile provided by the Instituto Água e Terra (IAT) was employed for spatial delineation of the studied landscape mosaic. Landscape structure analyses were conducted using ArcGIS 10.3, and functional connectivity assessments were carried out using Conefor Sensinode 2.6. This spatial delineation resulted in the functional analysis of 266 remnants of native vegetation, encompassing a wide range of area sizes, accounting for 28.75% (11,209.74 hectares) of the studied landscape mosaic. Among these patches, 255 (95.86%) were categorized as having low connectivity, 10 (3.76%) as having moderate connectivity, and only one (0.38%) as having high connectivity. The dIIC index for the high-priority patch (=78.50%) indicates that, despite the current landscape conditions differing significantly from the original state, it remains suitable for Tapirus terrestris. The most crucial habitat patch for functional landscape connectivity, considering the species' dispersal capacity of 2,000 meters, is the one encompassing PEMG. In conclusion, despite having a predominantly anthropogenic matrix, the buffer zone (ZA) of PEMG exhibits connectivity indices demonstrating a substantial degree of connectivity, primarily maintained by a single habitat patch that includes PEMG.

Temporal dynamics in the composition of bird communities along a gradient of farmland restoration.

Revegetation plantings are a key activity in farmland restoration and are commonly assumed to support biotic communities that, with time, replicate those of reference habitats. Restoration outcomes, however, can be highly variable and difficult to predict; hence there is value in quantifying restoration success to improve future efforts. We test the expectation that, over time, revegetation will restore bird communities to match those in reference habitats; and assess whether specific planting attributes enhance restoration success. We surveyed birds in 255 sites in south-east Australia, arranged along a restoration gradient encompassing three habitat types: unrestored farmland (paddocks), revegetation plantings (comprising a chronosequence up to 52 years old) and reference habitats (remnant native vegetation). Surveys were undertaken in 2006/2007 and again in 2019, with data used to compare bird assemblages between habitat types. We also determined whether, in the intervening 12 years, bird communities in revegetation had shifted toward reference habitats on the restoration gradient. Our results showed that each habitat contained a unique bird community and that, over time, assemblages in revegetation diverged away from those in unrestored farmland and converged toward those in reference habitats. Two planting attributes influenced this transition: the bird assemblages of revegetation were more likely to have diverged away from those of unrestored farmland (with scattered mature trees) 12 years later if they were located in areas with more surrounding tree cover, and were mostly ungrazed by livestock (compared with grazed plantings). Our results highlight three key ways in which revegetation contributes to farmland restoration: (1) by supporting richer and more diverse bird assemblages than unrestored farmland, (2) by enhancing beta diversity in rural landscapes through the addition of a unique bird community, and (3) by shifting bird assemblages toward those found in reference habitats over time. However, revegetation plantings did not replicate reference habitats by ~40-50 years in our region, and complete convergence may take centuries. These findings have implications for environmental offset programs and mean that effective conservation in farmland environments depends on the retention and protection of natural and seminatural habitats as a parallel management strategy to complement restoration.

Patch size and breeding status influence movement patterns in the threatened Malleefowl (Leipoa ocellata)

AbstractInformation on the movement ecology of species can assist with identifying barriers to dispersal and appropriate management actions. We focus on the threatened Malleefowl (Leipoa ocellata) whose ability to move and disperse within fragmented landscapes is critical for their survival. We also investigate the possible effects of climate change on Malleefowl movement. We used solar‐powered GPS telemetry to collect movement data and determine the influence of breeding status, remnant vegetation patches and environmental variables. Seven Malleefowl were tracked between 1 and 50 months, resulting in 20 932 fixes. While breeding, Malleefowl had significantly smaller home ranges (92 ± 43 ha breeding; 609 ± 708 ha non‐breeding), moved shorter daily distances (1283 ± 605 breeding; 1567 ± 841 non‐breeding) and stayed closer to the incubation mound (349 ± 324 m breeding; 3293 ± 2715 m non‐breeding). Most Malleefowl effectively disassociated from the mound once breeding stopped, with two birds dispersing up to 10.2 km. Movement patterns were significantly correlated with the size of the remnant native vegetation patch, with smaller home ranges being utilized in small patches than in large patches. One male almost exclusively remained within a 107‐ha patch for over 4 years, but a female crossed between closely spaced uncleared patches. Long‐range movements of nearly 10 km daily displacement were recorded in large remnants almost exclusively when not breeding. Temperature and rain had a significant effect on movement: modelling suggests daily distances decline from 1.3 km at 25°C to 0.9 km at 45°C, with steeper declines over 30°C. The influence of patch size on movement patterns suggests that Malleefowl movement may be governed by the size of remnant patches and that habitat continuity may be important for facilitating recolonization after catastrophic events and maintaining genetic diversity. Climate change may reduce Malleefowl movement during hot, dry periods possibly affecting breeding success.

Quantifying the landscape-scale recovery of bird communities over time in response to on-farm restoration plantings

Restoring wooded vegetation to cleared agricultural landscapes is a global priority. Restoration is a dynamic, long-term process: individual plantings take years to develop specific resources, and the extent and pattern of plantings change through time. A rarely-tested assumption is that, over time, the biota of restored landscapes will converge towards that of unmodified landscapes. To test this, we compared temporal changes in bird communities in agricultural landscapes in which wooded vegetation was dominated either by planted or remnant native vegetation. In 2007 and 2019, we sampled birds within 23 landscapes (each 8 km2) representing gradients in cover (∼1–19 %) of remnant vegetation (n = 9 ‘remnant’ landscapes) and planted vegetation (n = 14 ‘restored’ landscapes). In 2007, remnant landscapes supported ∼20 % more woodland bird species than restored landscapes but by 2019 richness was similar. There was a strong, positive relationship between species richness and wooded vegetation cover in both landscape types; however, for a given vegetation cover, species richness was higher in remnant landscapes only in 2007. Community composition showed increasing convergence over time, but remnant and restored landscapes supported distinct bird communities in both 2007 and 2019. Our results highlight that: 1) restoring vegetation to agricultural landscapes can reverse the loss of bird species accompanying vegetation clearing, but recovery takes time; 2) landscape-scale restoration will benefit from ‘succession planning’; 3) retaining remnant habitats is crucial because their resources are difficult to replicate with restoration; 4) plantings provide complementary resources and so restored landscapes containing remnant habitats will benefit biodiversity beyond those with only replantings.

ENVIRONMENTAL FRAGILITY OF LAND SYSTEMS IN A HYDROGRAPHIC BASIN LOCATED IN THE SOUTH REGION OF THE STATE OF BAHIA, BRAZIL

The drainage system of a hydrographic basin is formed by integrated functional systems, which provide ideal conditions for studies aimed at conserving and preserving ecosystems. Given the need to protect remnants of native vegetation in the Atlantic Forest, this study identified the terrain systems of Una River Basin (BHRU), Bahia, through the technical application of terrain assessment and multi-criteria methodological approach. In addition, the identified systems were evaluated for their levels of potential and emerging frailty. The results showed that the BHRU is subdivided into 8 (eight) terrain systems. Considering the relationship between the natural dynamics of the environment and the pressures exerted by anthropogenic activities, it was found that alluvial and coastal systems have areas with high degree of emerging fragility (8.20% of the BHRU). This high degree of emerging fragility is due to its natural characteristics, allied to the increase of anthropized environments that contrast the Buerarema and pre-coast systems, which have more excellent environmental protection due to extensive vegetation cover on their slopes. The study's methodology was shown to be adequate for the identification and characterization of terrain systems in the BHRU and can be replicated in other ecoregions in the country.

Defining priority areas for conservation of poorly known species: A case study of the endemic Brazilian three-banded armadillo

Abstract Conservation of poorly known species is challenging as lack of knowledge on their specific requirements may hamper effective strategies. Here, by integrating biogeographical and landscape analyses, we show that informed actions can be delineated for species with limited presence-only data available. We combine species distribution and connectivity models with temporal land cover changes to define priority areas for conservation of the endemic Brazilian three-banded armadillo, one of the most threatened xenarthrans that was once considered extinct in the wild. We revealed that areas of savanna and grassland are the most suitable habitats for the species and that uplands in the Caatinga ecoregion have a greater likelihood for dispersal. The few remnant armadillo populations are spatially associated with core areas of natural vegetation remnants. Worrisomely, 76% of natural core areas were lost in the past 30 years, mirroring the species’ severe population decline. Preserving the remnant core natural areas should be a high priority to ensure the species’ survival. We highlight key areas for proactive and reactive conservation actions for the three-banded armadillo that will benefit other threatened sympatric species. Our integrative framework provides a set of valuable information for guided conservation management that can be replicated for other poorly known species.

Environmental Sustainability Index of Rural Properties in the Federal District, Brazil

The objective of this work was to build and apply environmental indicators to verify the environmental performance and diagnose the sustainability levels of the rural properties from Federal District, Brazil. Data analysis was performed based on the information required and declared to public administration. Exploratory sampling was applied, obtaining a sample population of 169 properties. It was decided to use the factor analysis methodology in order to verify the environmental performance and diagnose the sustainability levels of the rural properties. The results achieved allow us to state that most of the properties (91.49%) are in a state of severe unsustainability. The results also show that the remnants of native vegetation, when they exist, are not in sufficient proportion to the total size of the property according to what the legislation requires. The proposed model and the environmental indicators built from the environmental legislation proved to be an efficient, practical and low-cost tool for a satisfactory diagnosis about the measurement of the sustainability of Brazilian rural properties and in the identification of positive management situations in relation to the suitability for environmental laws.

Flight activity and dispersal of Rhyzopertha dominica (F.) (Coleoptera: Bostrichidae) and Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae) across a mixed agricultural landscape in southern Australia

To better understand the field ecology of stored grain beetles in southern Australia we monitored the flight activity of Rhyzopertha dominica (F.) and Tribolium castaneum (Herbst) over a 2 year period. We used target-specific pheromone lures and Lindgren funnel traps in open fields, at grain storages, and in remnant native vegetation. Over 35,000 R. dominica and 2,500 T. castaneum were caught. Significantly more R. dominica (46.4%) were caught in areas of remnant vegetation than at storage sites (29.2%) or in open fields (24.4%), suggesting this species may be utilising non-grain food sources in some areas. In contrast, the majority of T. castaneum (45.4%) were caught adjacent to storages. An intense summer heatwave (14 day mean maximum air temperature 41.9 °C) corresponded to captures of both species declining to near zero until the following spring. Sex ratios of both species varied significantly over time but were unaffected by habitat type. Two mark/release/recapture (MRR) trials using laboratory-reared R. dominica were conducted using a 1 km trap array and pheromone lures. The recovery rate for marked beetles in the first trial was 1.41%, however a subsequent experiment comparing fresh and weathered lures showed that lure attractancy declines to 50% between 3 and 4 days after deployment during hot weather (mean daily maximum air temperature 29.4 °C). When the MRR trial was repeated with lures replaced at shorter (2 day) intervals, the recovery rate rose to 3.27% and the number of wild R. dominica captured increased proportionately. The short half-life of rubber septum-based R. dominica pheromone lures needs to be considered when designing surveillance programs, particularly if attempts are being made to correlate R. dominica dispersal patterns to short-term weather events.

Leioproctus zephyr Prendergast (Hymenoptera, Colletidae, Leioproctus), an oligoletic new bee species with a distinctive clypeus

A new speciesLeioproctus zephyr(Hymenoptera: Colletidae) is described from both sexes.Leioproctus zephyrsp. nov.is remarkable in featuring a large longitudinal ridge on the clypeus. This diagnostic morphological feature present in both sexes, along with various other distinctive characters including the male genitalia, female hind-tibial spur, and glossa morphology, clearly distinguish this species from all otherLeioproctus. Along with these unique traits,L. zephyrcannot be classified into any of the existing subgenera ofLeioproctus, sharing some, but not all, of the characters of the subgeneraCeratocolletes,Charicolletes,ProtomorphaandOdontocolletes. DNA barcoding with the CO1 gene confirmed the sexes belonged to the same species and it did not match any previously barcoded species. This species is restricted to native vegetation remnants in the southwest Western Australian biodiversity hotspot, and is highly specialised, foraging only on a few species in the genusJacksonia(Fabaceae). The unusual clypeus may be an adaptation for foraging on the keeled papilionaceous flowers. The limited number of sites this species has been collected from and its oligolectic diet suggestL. zephyrshould be considered to be a species of conservation concern. Further taxonomic research is required to determine the phylogenetic position of this unusualLeioproctus.

Timber plantations do not homogenize soil arthropod diversity but do alter species composition

Landscape transformation for agriculture threatens global biodiversity through simplification of ecosystems. We determine whether large-scale timber plantations contribute to biotic homogenization of soil biodiversity relative to remnant natural vegetation. We examined ant and springtail alpha- and beta-diversity, and assemblage composition, among biotopes in two different climatic and soil regions in a subtropical area of South Africa. Surprisingly, we observed equally high levels of alpha- and beta-diversity in plantations (Eucalyptus and Pinus) as in natural biotopes (indigenous forest and grassland) for both taxa in both regions, except in the inland sites where ant species richness was highest in grassland. Furthermore, beta-diversity in all biotopes was mainly due to species replacement rather than nestedness. The high diversity in plantations is likely due to high environmental variation among plantation sites, likely providing diverse niche opportunities across plantations. A possible mechanism for the large proportion of shared species between natural areas and plantations is colonization of arthropods from natural areas into plantations and/or source populations surviving harvesting and tree planting and then their populations growing during long periods of tree maturation. Plantations and natural areas supported complementary assemblages, which builds on the idea that remnant natural vegetation in production landscapes is essential for conserving not only unique aboveground biodiversity, but also unique belowground biodiversity. Furthermore, timber plantations do not homogenize soil arthropod taxonomic diversity as expected. This contrasts with global trends on biodiversity response to land-use change and emphasizes that conservation principles for soil biodiversity may differ from those aimed at aboveground biodiversity.

Landscape genetics outperforms habitat suitability in predicting landscape resistance for congeneric cat species

AbstractAimThe use of landscape resistance maps to model connectivity has become an indispensable tool for species conservation. However, different methods can be used to estimate landscape resistance, but there is no consensus on which is the most reliable one. Therefore, comparing the performance of those methods in predicting resistance can be quite useful to understand their limitations and conservation implications. Our goal was to evaluate the accuracy of two commonly used approaches, habitat suitability modelling and landscape genetics, in estimating landscape resistance to genetic connectivity of two species of Neotropical cats (Leopardus guttulus and L. geoffroyi) across their ranges.LocationSouth America.TaxonFelidae—L. guttulus and L. geoffroyi.MethodsFor both species, we optimized a landscape genetics resistance surface using a restricted multivariate optimization approach and transformed a habitat suitability map into a resistance layer. We compared landscape resistance models created by these two approaches based on the models' Akaike information criterion scores and evaluated the similarities and differences in their predictions by calculating the correlation between the resistance layers and generating difference maps.ResultsThe genetic approach greatly outperformed the habitat suitability approach in explaining movement driving gene flow for both species. For the studied species, habitat preference and genetic connectivity are influenced by different landscape features. Habitat alteration imposes great resistance for genetic connectivity, and the presence of natural vegetation remnants within altered environments is essential for their conservation.Main conclusionsFor the studied species, the transformation of habitat suitability models into resistance surfaces is a poor proxy for permeability to dispersal, and the use of genetic data is more reliable in modelling connectivity for species conservation. Habitat suitability and landscape resistance are not equivalent or even proportional for these species.

Contrasting effects of light and noise pollution interact with natural vegetation remnants: Human-related indicators of the habitat suitability for ungulates in the urban landscape

The features of the urban landscape encouraging large ungulates expansion are not known. However, prevalence and abundance of wild boar Sus scrofa has been steadily increasing over the years, and nowadays the species has become a recognized component of urban wildlife in many parts of its range. The aim of this work was to select habitat and human-related factors that could affect the probability of the species occurrence and constitute the honest indicators of the habitat suitability for this ungulate in the urban landscape. The data on the presence of grubbed patches of ground (an honest indicator of occurrence) were collected on randomly selected sample plots (N = 100) within the city of Kraków (Poland). We found that wild boar used 45% of the sample plots. Whereas the occupied plots were spatially concentrated, the habitat variables increasing the probability of the species occurring in the urban landscape were the presence of large patches of woodland remnants and large areas of semi-natural meadows. However, the study also revealed a negative relationship between the presence of the species and artificial lighting but a positive one with anthropogenic noise pollution. Our results indicate that the urban landscape consists of surrogate habitats for this large mammal but light and noise pollution may have contrasting effects on the species’ occurrence. This indicates that the influence of human-related factors on the attractiveness of natural vegetation remnants for wildlife is more complex than merely a limiting factor. This reveals high potential of light and noise pollution as indicators of the habitat suitability for ungulates in the urban landscape.

Landscape attributes shape dung beetle diversity at multiple spatial scales in agricultural drylands

Land-use change is one of the main drivers of biodiversity loss worldwide, but its negative effects can vary depending on the spatial scale analyzed. Considering the continuous expansion of agricultural demand for land, it is urgent to identify the drivers that shape biological communities in order to balance agricultural production and biodiversity conservation in human-modified landscapes. We used a patch-landscape design and a multimodel inference approach to assess the effects of landscape composition and configuration at two spatial scales (patch and landscape) on the structure of dung beetle assemblages. We performed our study in the Caatinga, the largest dry forest in South America. We sampled 3,526 dung beetles belonging to 19 species and 11 genera. At patch scale, our findings highlight the positive relationship of forest cover and landscape heterogeneity with dung beetle diversity, which are the major drivers of beetle assemblages. Edge density, in turn, is a major driver at the landscape scale and has a negative effect on beetle diversity. Our results support the hypothesis that landscapes combining natural vegetation remnants and heterogeneous agricultural landscapes are the most effective at conserving the biodiversity of dung beetles in the Caatinga landscapes. Directing efforts to better understand the dynamics of dung beetles in agricultural lands can be helpful for policymakers and scientists to design agri-environment schemes and apply conservation strategies in tropical dry forests.