Habitat Fragmentation Research Articles

Divergent lineages in a young species: The case of datilillo (Yucca valida), a broadly distributed plant from the Baja California Peninsula.

Globally, barriers triggered by climatic changes have caused habitat fragmentation and population allopatric divergence. Across North America, oscillations during the Quaternary have played important roles in the distribution of wildlife. Notably, diverse plant species from the Baja California Peninsula in western North America, isolated during the Pleistocene glacial-interglacial cycles, exhibit strong genetic structure and highly concordant divergent lineages across their ranges. A representative plant genus of the peninsula is Yucca, with Y. valida having the widest range. Although a dominant species, it has an extensive distribution discontinuity between 26° N and 27° N, suggesting restricted gene flow. Moreover, historical distribution models indicate the absence of an area with suitable conditions for the species during the Last Interglacial, making it an interesting model for studying genetic divergence. We assembled 4411 SNPs from 147 plants of Y. valida throughout its range to examine its phylogeography to identify the number of genetic lineages, quantify their genetic differentiation, reconstruct their demographic history and estimate the age of the species. Three allopatric lineages were identified based on the SNPs. Our analyses support that genetic drift is the driver of genetic differentiation among these lineages. We estimated an age of less than 1 million years for the common ancestor of Y. valida and its sister species. Habitat fragmentation caused by climatic changes, low dispersal, and an extensive geographical range gap acted as cumulative mechanisms leading to allopatric divergence in Y. valida.

Landscape structure influences the spatial distribution of urban bird attractiveness

ContextLandscape change affects biological diversity and the distribution of species traits related to spiritual, educational, and recreational benefits people derive from nature. These traits are associated with color, song and behavioral characteristics that influence people's perceptions of how attractive an assemblage is. However, the environmental variables that affect the spatial distribution of traits related to the attractiveness of biological diversity remain unexplored.ObjectivesWe tested how landscape structure influences patterns of perceived bird attractiveness (trait diversity associated with colorfulness, behavioral and song categories) across an urbanization gradient.MethodsWe used data from standardized surveys of birds and landscapes within 42 landscape units of 1km2 across the city of Brisbane in eastern Australia. We used structural equation modeling to test effects of landscape composition (built infrastructure, percentage of tree cover) and landscape configuration (fragmentation of tree cover) on mean bird community attractiveness. Relationships between individual traits and landscape structure were analyzed using multinomial logistic regression models.ResultsOur analysis across 82 bird species shows that the relative amount of built infrastructure in a landscape interacts with fragmentation to reduce the overall attractiveness of the landscape’s bird assemblage. However, built areas can exhibit high overall bird attractiveness where there is (1) reduced fragmentation and (2) increased diversity of vegetation structure that provides key habitats for many colorful species with a high diversity of calls. Relationships between bird attractiveness and landscape structure change when they are analyzed at the guild level (insectivores vs frugivores/nectarivores). In addition, body size moderates the effects of landscape structure on song complexity, personality, and color.ConclusionsSmall bodied, colorful and melodious species are negatively affected by built infrastructure and fragmentation. By learning how habitat loss and fragmentation affect the distribution of species-rich, attractive bird assemblages, our findings can inform how urban landscapes might be structured to increase people’s connection with nature.

Forest fragmentation and connectivity in South American dry forests

Forest fragmentation and connectivity in South American dry forests

Identification of landscape features structuring movement connectivity for Namibian elephants

ContextHuman modification of landscapes poses a significant threat to wildlife, particularly in Africa where population growth and land conversion are expected to increase. Habitat loss and fragmentation have led to declines in wildlife populations, highlighting the need to identify and preserve critical habitats, including core use areas and connectivity between them. Most recently, the identification of habitat corridors has become a key objective.ObjectivesOur study objectives are to (1) empirically quantify connectivity across the Kunene—Etosha landscape in Northwestern Namibia using GPS tracking data on wild African elephants, and (2) assess the landscape features (i.e., geologic, biotic, and human-made) influencing connectivity and corridor types (e.g., fast movement corridors versus slow multi-use movement corridors).MethodsWe used GPS telemetry data from 66 elephants collared in Northwestern Namibia to empirically quantify connectivity using a graph theoretic approach and assess landscape features influencing connectivity. Based on the ‘movescape’ approach, we identify different types of corridors and examined how landscape features differed across these corridors using multiple regression models on locations classified into different types of use categories by machine learning algorithms.ResultsOur results revealed strong variation in connectivity across the landscape, with paths of high connectivity near water sources between the study areas. We found that factors related to water sources and human presence primarily influenced connectivity. Water holes serve as hubs across the ecosystem for both male and female elephants with lower use areas peripheral to areas with water. Connectivity between Kunene and Etosha National Park was relatively rare among the collared elephants, but we highlight the key areas used to move between the two regions.ConclusionWater was the key feature structuring space use, and human presence influenced connectivity between water points, highlighting the importance of landscape planning in relation to limited water sources and human activities. Our results suggest that focusing management efforts on areas where water is limited for both elephants and humans will be important to reduce conflict and maintain ecosystem connectivity.

Network resilience of plant-bee interactions in the Eastern Afromontane Biodiversity Hotspot

Interaction network resilience can be defined as the ability of interacting organisms to maintain their functions, processes or populations after experiencing a disturbance. Studies on mutualistic interactions between plants and pollinators along environmental gradients are essential to understand the provision of ecosystem services and the mechanisms challenging their network resilience. However, it remains unknown to what level ecological changes along climatic gradients constrain the network resilience of mutualistic organisms, especially along elevation gradients. We surveyed bee species and recorded their interactions with plants throughout the four major seasons (i.e. long and short rainy, and long and short dry) on 50 study sites positioned along an elevation gradient (525 m to 2,530 m asl) in the Eastern Afromontane Biodiversity Hotspots in Kenya, East Africa. We calculated bee and plant network resilience using the network resilience parameter (βeff) and assessed changes in bee and plant network resilience along the elevation gradient using generalised additive models (gams). We quantified the effects of climate, bee and plant diversity, bee functional traits, network structure, and landscape configuration on bee and plant network resilience using a set of multi-model inference frameworks followed by structural equation models (SEM). We found that bee and plant species exhibited higher levels of network resilience at higher elevations. While bee network resilience increased linearly across the elevation gradient, plant network resilience increased exponentially from ∼1500 m and higher. Bee and plant network resilience increased in areas with reduced mean annual temperature (MAT) and decreased in areas with lower mean annual precipitation (MAP). Our SEM model showed that increasing temperatures indirectly influenced plant network resilience via network modularity and community assemblage of bees. We also found that MAP had a direct positive effect on plant diversity and network resilience, while the fragmentation of habitats reduced richness of plant communities and enhanced network modularity. In conclusion, we revealed that mutualistic networks showed higher network resilience at higher elevations. We also unveiled that climate and habitat fragmentation directly or indirectly influences the network resilience of plants and bees via the modulation of community assemblages and interaction networks. These influences are lower at higher elevations such that these systems seem better able to buffer against extinction cascades. We thus suggest that, management efforts should be geared at consolidating natural habitats. In contrast, restoration efforts should aim at mitigating climate change effects and harnessing the ability of mutualists to reconnect broken links to improve the network resilience and functioning of East-African montane ecosystems.

Host specialization and spatial divergence of bacteria associated with Peltigera lichens promote landscape gamma diversity

BackgroundLichens are micro-ecosystems relying on diverse microorganisms for nutrient cycling, environmental adaptation, and structural support. We investigated the spatial-scale dependency of factors shaping the ecological processes that govern lichen-associated bacteria. We hypothesize that lichens function as island-like habitats hosting divergent microbiomes and promoting landscape gamma-diversity. Three microenvironments —thalli, substrates, and neighboring soils— were sampled from four geographically overlapping species of Peltigera cyanolichens, spanning three bioclimatic zones in the Chilean Patagonia, to determine how bacterial diversity, assembly processes, ecological drivers, interaction patterns, and niche breadth vary among Peltigera microenvironments on a broad geographical scale.ResultsThe hosts’ phylogeny, especially that of the cyanobiont, alongside climate as a secondary factor, impose a strong ecological filtering of bacterial communities within Peltigera thalli. This results in deterministically assembled, low diverse, and phylogenetically convergent yet structurally divergent bacterial communities. Host evolutionary and geographic distances accentuate the divergence in bacterial community composition of Peltigera thalli. Compared to soil and substrate, Peltigera thalli harbor specialized and locally adapted bacterial taxa, conforming sparse and weak ecological networks.ConclusionsThe findings suggest that Petigera thalli create fragmented habitats that foster landscape bacterial gamma-diversity. This underscores the importance of preserving lichens for maintaining a potential reservoir of specialized bacteria.

Land-cover gradients determine alternate drivers of mammalian species richness in fragmented landscapes

ContextUnderstanding habitat fragmentation is a critical concern for nature conservation and the focus of intense debate in landscape ecology. Resolving the uncertainty around the effects of habitat fragmentation on biodiversity remains an ongoing challenge that requires the successful delineation of multiple patch-landscape interactions.ObjectivesWe carried out a regional analysis on species richness of woodland mammals to determine the relative influence of structural, compositional and functional characteristics related to woodland habitat across different land-cover gradients.MethodsWe calculated the Edge-weighted Habitat Index, an area-weighted measure of functional connectivity that incorporates a mechanistic estimate of edge-effects, for interior woodland habitat. We compared its influence on mammalian species richness to that of increasing edge and patch density, landscape diversity, and a habitat-only model, in different contexts of matrix hostility across Northern England in the UK.ResultsOur results demonstrate the relevance of alternative drivers of species richness resulting from patch-landscape interactions across gradients of matrix hostility. Evidence is provided for positive and negative effects of increasing structural (edge density), functional (connected interior habitat) and compositional (landscape diversity) attributes, varying according to matrix type and intensity. Results were sensitive to dominant land-cover types in the matrix and the scale of observation.ConclusionThis study provides new insights into fragmentation effects on biodiversity and clarifies assumptions around the relative influence of structural, compositional and functional habitat characteristics on landscape-level species richness. We highlight the presence of thresholds, related to matrix hostility, that determine alternative drivers of species richness in woodland mammals. These drivers, and related thresholds, were sensitive to the scale of observation and landscape context. Landscape decisions aimed at promoting biodiversity should consider sources of matrix hostility and homogeneity at scales relevant to ecological processes of interest.

Resurrecting a locally extinct species from Jordan: Pre-germination treatments affect seed dormancy, germination dynamics and seedling survival in Rosa pulverulenta.

Habitat loss, fragmentation, and climate change present significant threats to global plant biodiversity. Small and isolated populations residing in threatened habitats at the edge of their natural distribution are particularly vulnerable to local extinction. Rosa pulverulenta M.Bieb., had its southernmost distribution in the Mediterranean basin in Jordan, but this remnant population recently extinct in the wild. Our goal to resurrect this species is hindered by the limited availability of seeds from the extinct population and a high degree of combinational dormancy in R. pulverulenta. To preserve as many genotypes as possible for eventual reintroduction, we aimed to identify the most effective seed treatment for breaking seed dormancy, and enhancing germination, and seedling establishment. Seeds were collected one season before extinction. We applied seven pre-germination treatments. The pre-treated seeds were then germinated at three temperature regimes (4/4 °C, 20/15 °C, and 25/20 °C), simulating winter and spring germination conditions. Warm-cold stratification, integral to all pre-treatments, proved effective in dormancy release, significantly enhancing germination. The highest germination (68 %) occurred at 4 °C, particularly in seeds treated with warm-cold stratification alone. Conversely, minimal germination was observed at higher temperatures (20/15 °C and 25/20 °C), suggesting potential induction of secondary dormancy. Furthermore, warm-cold stratification, especially when followed by microbial fertilizer, positively impacted seedling survival. Our study provides insights into effectively resurrecting the southernmost boundary of R. pulverulenta distribution in the Mediterranean basin, thereby preventing the global decline in the species' extent of occurrence. Strategically releasing seed dormancy and enhancing germination has important implications on scientific efforts reversing the declining trend of biodiversity in the Anthropocene. Additionally, seed collection from populations on the brink of extinction for resurrection is crucially required as the best method to preserve their genetic diversity. Therefore, this work offers a valuable framework that can be adapted to similar conservation efforts for other endangered plant species facing comparable threats. We emphasize the importance of further investigating how climate change can negatively affect seed dormancy, germination, and plant regeneration, ultimately leading to the local extinction of threatened populations.

Diversity and seasonality of horse flies (Diptera: Tabanidae) in Amazon Forest fragments of Monte Negro, Rondônia, Western Amazon.

Tabanidae are considered a nuisance to humans, wild animals, and livestock due to their painful, annoying, and insistent biting. Tabanids transmit some pathogens and parasites biologically and mechanically. In humans, there are relatively few pathogens transmitted regularly. Still, tabanids serve as vectors of a number of disease agents of animals, including viruses, bacteria, protozoans, and nematodes. They are more abundant in tropical and humid regions, and their seasonal patterns are affected by habitat changes such as deforestation and fragmentation. Here, we analyze the tabanid fauna in Monte Negro, a central municipality of Rondônia, Brazil, comparing abundance, richness, and diversity in forest and pasture habitats. Traps were set for 5days a month for 12 consecutive months. We also examined how abiotic factors (humidity, temperature, and rainfall) affected the abundance, diversity, and richness and the effectiveness of Malaise and Nzi traps as sample methods. The influence of climatic variables on the richness and abundance of the species was tested using generalized linear models, and we used non-parametric dimensional scaling (nMDS) for analysis of species composition and diversity in different traps and environments. We collect 1032 specimens of 25 species. The most abundant species were Tabanus antarcticus, Dichelacera tetradelta, Tabanus mucronatus, and Leucotabanus albovarius. Forest habitats had the highest number of tabanids, followed by pasture and the anthropized area, and there was no significant difference regarding the effectiveness of the Malaise and Nzi traps. The study provides new information on the distribution and ecology of tabanids in Brazil.

Species distribution models predict genetic isolation of Hetaerina vulnerata Hagen in Selys, 1853 (Odonata, Calopterygidae).

Understanding how past and current environmental conditions shape the demographic and genetic distributions of organisms facilitates our predictions of how future environmental patterns may affect populations. The Canyon Rubyspot damselfly (Odonata: Zygoptera: Hetaerina vulnerata) is an insect with a range distribution from Colombia to the arid southwestern United States, where it inhabits shaded mountain streams in the arid southwestern United States. Past spatial fragmentation of habitat and limited dispersal capacity of H. vulnerata may cause population isolation and genetic differentiation, and projected climate change may exacerbate isolation by further restricting the species' distribution. We constructed species distribution models (SDMs) based on occurrences of H. vulnerata and environmental variables characterizing the species' niche. We inferred seven current potential population clusters isolated by unsuitable habitat. Paleoclimate models indicated habitat contiguity in past conditions; projected models indicated some habitat fragmentation in future scenarios. Seventy-eight H. vulnerata individuals from six of the current clusters were sequenced via ddRADseq and processed with Stacks. Principal components and phylogeographic analyses resolved three subpopulations; Structure resolved four subpopulations. F ST values were low (<0.05) for nearby populations and >0.15 for populations separated by expanses of unsuitable habitat. Isolation by distance was an existing but weak factor in determining genomic structure; isolation by environment and the intervening landscape explained a significant proportion of genetic distance. Hetaerina vulnerata populations were shown to be isolated by a lack of tree canopy coverage, an important habitat predictor for oviposition and territoriality. Thus, H. vulnerata populations are likely separated and are genetically isolated. Integrating SDMs with landscape genetics allowed us to identify populations separated by distance and unsuitable habitat, explaining population genetic patterns and probable fates for populations under future climate scenarios.

Masked invader in Iran! Habitat suitability analysis for invasive raccoon (Procyon lotor) in the west of Guilan Province.

Nowadays, in addition to the destruction and fragmentation of the world's habitats, invasive species, and damage caused by them, are one of the most important factors in the destruction of ecosystems. The raccoon (Procyon lotor) is a medium-sized mammal that is placed in mid-levels of the food web and can affect a wide range of species. Considering the damage done to local ecosystems by this invasive species, habitat assessment and determining the factors affecting its habitat suitability would be a key step in managing this species. In this study, using the MaxEnt model and examining 12 environmental parameters (elevation, slope, aspect, geological units, soil type, vegetation, land use, distance to villages, distance to main roads, distance to waterways, average temperature, and rainfall) in the west of Guilan Province, habitat suitability of this alien species was determined, and the most important factors affecting this suitability were investigated. Results showed that the validity value of the model (AUC) was estimated to be 0.852 and parameters such as distance to village (34.5%), elevation (24.2%), and land use (15.9%) are among the most important and effective factors. Also, the results showed that 0.60% of the study area has high suitability, 6.14% moderate, 24.87% low, and 68.36% unsuitable areas for raccoons. The overall result shows that despite the lack of vast favorable areas for this invasive species, an increase in the number and expansion of this species is very likely because of its omnivorous diet, high adaptability to different environments and conditions, as well as extensive niche. All of these factors cause raccoons to spread further in the region and consequently increase the risks and damages to the native ecosystem.

Spatial bias in sampling small rodents in the Atlantic Forest: A landscape and accessibility perspective

Understanding the effects of habitat loss and fragmentation on species spatial distribution is challenging, mainly because knowledge of species occurrences is biased. Survey efforts are unevenly distributed causing spatial sampling biases that are normally neglected. Assessing sampling bias is particularly urgent for threatened ecoregions, such as the Atlantic Forest, a global biodiversity hotspot. Here, we assess spatial sampling biases of small rodents in the Atlantic Forest, using an integrative approach with accessibility and landscape metrics. We built a robust dataset of 11,495 primary records of the Atlantic Forest’s small rodent species, based on information from digitally accessible repositories. We expect that well-sampled sites are spatially aggregated and nearer roads, urban centers, on landscapes with larger forest fragments, and with higher percentage of forest cover. We also expect gaps of small rodents sampling in rare landscape conditions. Our results indicated that only less than 1% of the Atlantic Forest (at 1 km2 cell-size resolution) are well sampled. Following our expectations, the well-sampled sites were spatially aggregated biased toward roads, urban centers, larger forest fragments, and landscapes with higher percentage of forest cover. We also found a survey gap on common landscape conditions. Our findings suggest that the spatial distribution of small rodents at landscape level (1 km2) remains unknown across most of the Atlantic Forest spatial extension. Our findings also point to new priority sites for small mammals sampling on common landscape conditions, in smaller fragments and on remote areas improving spatial distribution knowledge and contributing to conservation policies at landscape level.

Combining spaceborne lidar from the Global Ecosystem Dynamics Investigation with local knowledge for monitoring fragmented tropical landscapes: A case study in the forest-agriculture interface of Ucayali, Peru.

Improving our ability to monitor fragmented tropical ecosystems is a critical step in supporting the stewardship of these complex landscapes. We investigated the structural characteristics of vegetation classes in Ucayali, Peru, employing a co-production approach. The vegetation classes included three agricultural classes (mature oil palm, monocrop cacao, and agroforestry cacao plantations) and three forest regeneration classes (mature lowland forest, secondary lowland forest, and young lowland vegetation regrowth). We combined local knowledge with spaceborne lidar from NASA's Global Ecosystem Dynamics Investigation mission to classify vegetation and characterize the horizontal and vertical structure of each vegetation class. Mature lowland forest had consistently higher mean canopy height and lower canopy height variance than secondary lowland forest (μ = 29.40 m, sd = 6.89 m vs. μ = 20.82 m, sd = 9.15 m, respectively). The lower variance of mature forest could be attributed to the range of forest development ages in the secondary forest patches. However, secondary forests exhibited a similar vertical profile to mature forests, with each cumulative energy percentile increasing at similar rates. We also observed similar mean and standard deviations in relative height ratios (RH50/RH95) for mature forest, secondary forest, and oil palm even when removing the negative values from the relative height ratios and interpolating from above-ground returns only (mean RH50/RH95 of 0.58, 0.54, and 0.53 for mature forest, secondary forest, and oil palm, respectively) (p < .0001). This pattern differed from our original expectations based on local knowledge and existing tropical forest succession studies, pointing to opportunities for future work. Our findings suggest that lidar-based relative height metrics can complement local information and other remote sensing approaches that rely on optical imagery, which are limited by extensive cloud cover in the tropics. We show that characterizing ecosystem structure with a co-production approach can support addressing both the technical and social challenges of monitoring and managing fragmented tropical landscapes.

Forest fragmentation effects on mutualistic interactions: frugivorous birds and fruiting trees

While many effects of forest fragmentation are reasonably well understood, knowledge of interspecific interactions in fragmented ecosystems is much more limited, particularly for high diversity tropical forests. Using nearly 40 years of data from the Biological Dynamics of Forest Fragments Project in Central Amazonia, we assessed whether forest fragment area and time since isolation impact mutualistic interactions between frugivorous birds and their food resources. We used structural equation modeling to analyze the complex pathways between four main variables determining these interactions: fruiting tree abundance, frugivorous bird abundance, forest fragment area, and time since fragment isolation. Our results confirm that fragment area alters the abundance of some tree resources, with successional plant families increasing in abundance with decreasing fragment size. However, these changes do not drive alterations in the abundance of frugivorous birds. We also tested if bird species with a greater relative diet breadth are less vulnerable to forest fragmentation and found that specialist frugivores are more vulnerable to forest fragmentation immediately after isolation but are not differentially impacted within the long term. Collectively, our results demonstrate the need to further evaluate human‐driven habitat change across multiple timescales to fully understand its impacts on complex species interactions.

Negative relationship between body mass and home range size in three-toed sloths of the Amazon rainforest

ABSTRACT The spatial use of habitat is key to understanding the ecology of animals and their area requirements. In the current study, the locations of 11 wild pale-throated three-toed sloths (Bradypus tridactylus) were tracked using GPS loggers across 92 days in a 776 ha forest fragment in the central Amazon. Although male home ranges were slightly smaller than those of females, there were no significant differences in size or its expansion patterns. For nine of 11 individuals, home range size reached a plateau within 45 days of study start, indicating that 45 days can be the basal minimum days to establish the home range size of B. tridactylus. There was a negative relationship between body mass and home range size in our study. This counterintuitive result may be caused by disparities in the food-exploring abilities between individuals. Smaller and presumably younger individuals, who have less experience, may require more time and a larger area in which to search for food, while older and more experienced individuals may be able to find food efficiently in a smaller area. Further work on the distribution of food plants and the food-exploring pattern of each animal in relation to age and/or size is thus encouraged.

Forest Clearance and Fragmentation for Charcoal Production: The Case of Bimbia Bonadikombo Forest, South West Region, Cameroon

The exploitation activities of man on natural resources have hardly been sustainable. This study examined the implication of charcoal production on the Bimbia Bonadikombo forest and it’s environ. The study employed both direct field observation and questionnaire administration for data gathering. Questionnaires were administered to charcoal producers and persons involved in charcoal related activities. Persons were selected using snowball technique. A total of 42 copies of questionnaires were administered to charcoal producers and related activities. Tree species used for charcoal production were noted and identified. The questionnaire was divided into five sections:(i), socio-demographic characteristics of charcoal producers, (ii), methods of charcoal production and species selected (iii), aspects influencing charcoal production and the implication on the ecosystem, (iv), seasonal trends and challenges faced (v) mitigation strategies used). Data collected were organized in Microsoft Excel and Statistical Package for Social Sciences (SPSS) was used for the analyses. Pearson (ρ) correlation association was used for the relationship between variables of production and the demand of charcoal. The result revealed that, majority of the respondents, 78.57%, were males while females were least 21.43%. Majority of the respondents (54.76%) were between the ages of 31-46 while the least with ages &gt; 47. Lophira alata 14 (35.71%) was the tree species ranked 1st while Irvingia gabonensis1 (2.38%) was the least and ranked 8th. The main aspect that influenced production was revenue generated 14 (33.33%) while weak institutions 2(4.76%) and crises situations 2(2(4.76%) were the least. Deforestation 12(28.57%) and habitats destruction 8(10.04%) were reported as the main effects caused by charcoal production. Production and the demand of charcoal variables showed a positive association (0.153±.361). The management strategies employed were: only matured trees were used for charcoal production, permanent charcoal pit kiln are dug out of forest canopy and only few tree species are used for charcoal production. For mitigation purposes used are: domestication, protecting wild charcoal trees in their farms and nurseries establishment. This study recommends that charcoal is a major source of energy and alternative source of energy when others failed or insufficient. Therefore, this source of energy can be enhanced to be more eco friendly and environmentally sustainable.

Proximity among protected area networks promotes functional connectivity for wintering waterfowl

The equilibrium theorem provided a fundamental framework for understanding species’ distributions and movement in fragmented ecosystems. Wetland-dependent avian species are model organisms to test insular predictions within protected area networks because their mobility allows surveillance of isolated patches without landscape barriers. We hypothesized size and isolation would influence functional connectivity of sanctuaries by GPS-marked wintering mallards (Anas platyrhynchos) within a mesocosm protected sanctuary area network. We evaluated functional connectivity and sanctuary use, measured by movements between sanctuaries, using a multistate modeling framework. Proximity drove connectivity, underscoring that patch isolation—not size—influenced connectivity, even for an avian species with no ascertainable landscape resistance or barriers. We also found that sanctuary use increased overwintering survival by reducing harvest mortality. Our test of equilibrium theory predictions demonstrated that isolation of protected sanctuary areas supersedes their size in determining functional connectivity for mallards and access to these areas may have direct fitness consequences. Our findings could refine land acquisition, restoration, and management practices with equal or greater emphasis on adjacency in protected area network design, especially for wetland-dependent migratory gamebirds.

Applications of Primate Genetics for Conservation and Management

Conservation genetics is the use of genetics to understand and mitigate the threats caused by anthropogenic activities, including habitat loss and fragmentation, wildlife trafficking, and emerging diseases. In this review, we discuss the role of primate conservation genetics in the development of effective conservation strategies, emphasizing the importance of maintaining genetic diversity to enhance adaptive potential and prevent extinction. First, we discuss studies of various primate species that exemplify how genetic data have been instrumental in accurately assessing threat levels, identifying trafficked animals and tracing their geographic origin, and studying how habitat loss affects primate populations. Subsequently, we describe the various molecular tools and analytical approaches employed in these studies. Lastly, we provide a bibliographic review of research in conservation genetics over the last 20 years. We conclude with a brief discussion of the limitations and challenges in this field in developing countries and recommendations for future research.

Relational geographies of urban unsustainability: The entanglement of California’s housing crisis with WUI growth and climate change

One of California’s most pressing social and environmental challenges is the rapid expansion of the wildlands–urban interface (WUI). Multiple issues associated with WUI growth compared to more dense and compact urban form are of concern—including greatly increased fire risk, greenhouse gas emissions, and fragmentation of habitat. However, little is understood about the factors driving this growth in the first place and, specifically, its relationship to urban–regional housing dynamics. This paper connects work in urban social science, urban and regional planning, and natural sciences to highlight the potential role of housing crises in driving displacement from the urban core to relatively more affordable exurbs, and with this, WUI growth. We analyze this relationship in California, which leads the nation in lack of affordable housing, scale of WUI growth, and many associated WUI hazards, including wildfire. We offer three related arguments: first, that California’s affordable housing crisis, with its effect of driving migration to exurban areas, should be recognized as a significant urban form-related sustainability challenge; second, that to understand this challenge scholars must expand the spatial scale and analytic toolkit of both urban and WUI analysis through relational, mixed methods research; and third, that political and programmatic efforts to address California’s housing crisis should undergird efforts to address WUI growth and climate change. Ultimately, we argue that expanding access to affordable urban housing can produce a more sustainable and just urban form that mitigates WUI-related climate and environmental impacts and reduces the vulnerability of growing numbers of WUI residents living in harm’s way.

Temporal variation and age influence activity budget more than sex and reproductive status in wild brown howler monkeys (Alouatta guariba clamitans) inhabiting a large, continuous forest.

Activity budget analyses are important for understanding how animals spend their time in daily activities like resting, foraging, moving and socializing. These behaviors are closely linked to energy management, so habitat quality and resource availability are known to influence the activity budgets of species. Therefore, many studies have examined the consequences of habitat loss and fragmentation on the energetic demands and activity budgets of species. However, we still have limited knowledge of how animals behave in large, continuous, and protected environments, as such habitats are currently rare. The present study analyzed how temporal variation, age, sex and reproductive status influenced the activity budget of wild red howler monkeys (Alouatta guariba clamitans), in one of the last Atlantic Forest remnants that remains large and protected. Between November 2017 and December 2018, we monitored two groups, G3 and G4, in Parque Estadual Carlos Botelho, São Paulo, Brazil. The groups were composed of one adult male, two adult females and their offspring and one (G3) or two (G4) subadult males, using scan sampling for behavioral for data collection every 20min. The most common behavior was resting, followed by foraging, moving and social interactions, with inter-group differences. Temporal variation explained most of the fluctuations in the activity budget, so did age and sex, but to a lesser degree. The reproductive status of females did not alter their activity budget. These findings reveal that even neighboring groups display distinct and intricate relationships with their habitat. Future studies should be conducted in continuous forests to determine what is the expected range of variation in activity budget, particularly in those species considered as flexible and inhabiting endangered habitats, such as the Atlantic Forest.