Habitat Changes Research Articles

Impacts of terrestrial mammalian herbivores on vegetation change in the arctic

AbstractThere are increasing concerns about regional ecosystem shifts in the Arctic due to climate change. Notably, warming-induced increases in Arctic vegetation cover can have important consequences for surface energy balance, habitat changes, permafrost, and more. Mammalian herbivory is an important potential force to counteract this effect. In this systematic literature review, we examine the role of terrestrial mammalian herbivory on warming-induced increases in Arctic vegetation. We analyse the effects of terrestrial mammalian herbivory on vegetation cover, abundance, growth, survival, and ecosystem productivity. Our results show that herbivory has an overall significant negative influence on Arctic vegetation, particularly on vegetation biomass, growth, and productivity, as indicated by the Normalised Difference Vegetation Index (NDVI). Importantly, we demonstrated a significant role of herbivores in controlling carbon dioxide exchange and carbon uptake, whilst acknowledging that the relationship between herbivory and ecosystem productivity is highly complex and site-dependent. Our results confirm the important role that herbivory can play in buffering observed and predicted warming-induced Arctic vegetation increases. We also find that this is strongly affected by plant palatability, trampling occurrence, and herbivore density. Graphical Abstract

Comparative Phylogeography of Two Specialist Rodents in Forest Fragments in Kenya

The fragmented forests of the Kenya highlands, known for their exceptional species richness and endemism, are among the world’s most important biodiversity hotspots. However, detailed studies on the fauna of these ecosystems—especially specialist species that depend on moist forests, which are particularly threatened by habitat fragmentation—are still limited. In this study, we used mitochondrial genes (cytochrome b and the displacement loop) and a nuclear marker (retinol-binding protein 3) to investigate genetic and morphological diversity, phylogenetic associations, historical divergence, population dynamics, and phylogeographic patterns in two rodent species—the soft-furred mouse (Praomys jacksoni) and the African wood mouse (Hylomyscus endorobae)—across Kenya’s forest landscapes. We found a complex genetic structure, with P. jacksoni exhibiting greater genetic diversity than H. endorobae. The Mt. Kenya P. jacksoni populations are significantly genetically different from those in southwestern forests (Mau Forest, Kakamega Forest, and Loita Hills). In contrast, H. endorobae presented no observable biogeographic structuring across its range. The genetic diversity and geographic structuring patterns highlighted selectively strong effects of forest fragmentation and differing species’ ecological and evolutionary responses to these landscape changes. Our findings further underscore the need for expanded sampling across Kenya’s highland forests to better understand species’ changing diversity and distribution patterns in response to the impacts of human-mediated habitat changes. These insights are critical for informing conservation strategies to preserve biodiversity better in this globally important region.

Species distribution modeling of North American beavers from the late Pliocene into the future

Abstract Beavers have occurred in North America since at least 7 Ma, but relatively little is known about their distribution across the continent. We modeled distributions of beavers in the late Pliocene (3.3 Ma), Pleistocene (130 ka and 21 ka), and recent Holocene (1970 to 2000) to understand their dispersal across North America, predict future distributions and predict their possible response to future climate and habitat changes. Occurrence data for Castor canadensis were derived from the Global Biodiversity Information Facility. Those data were used with both modern (1970 to 2000) and modeled future (EC-Earth-Veg 2081 to 2100) bioclimatic variables from WorldClim as well as past (Pliocene Marine Isotope Stage M2, Pleistocene Last Interglacial, and Pleistocene Last Glacial Maximum) bioclimatic variables from PaleoClim to model beaver distributions through time. Fossil locality points for Castor extracted from the New and Old Worlds Database of Fossil Mammals (NOW), NEOTOMA Paleoecology Database, and Paleobiology Database were overlain on past projection models to use as validation points. Models were run using MaxEnt with post-processing in ArcGIS. Accuracy for the 5 models ranged between 59.6% and 60.2%. Results for the present model (1970 to 2000) showed habitat suitability in areas beavers inhabit today. During the Pliocene MIS M2 cooling event (3.3 Ma) and Pleistocene Last Glacial Maximum (21 ka), habitat suitability shifted further south into Mexico and peninsular Florida and away from more periglacial northern regions. During the Last Interglacial period (130 ka) and modeled future (2081 to 2100) EC-Earth-Veg 2081 to 2100, habitat suitability was higher in coastal and central regions in North America and lower in southern regions compared to their present distribution. Distributions were most affected by precipitation seasonality, isothermality, and mean annual temperature. High variability in seasonal precipitation and temperatures is likely to influence surface water availability, vegetation type, and riparian vegetation composition, which consequently may reduce available food resources and habitat for beavers. Observed shifts during warmer periods may indicate areas in the late Miocene that facilitated dispersal into North America. Future models using other predicted climatic scenarios and shared socioeconomic pathways may provide better resolution of potential future shifts in beaver distribution with best- and worst-case climate scenarios, thereby permitting at-risk areas to be prioritized for conservation in the face of climate change.

Depopulation and Changes in Habitat Type in Rural Areas in Aragón (Spain)

Objective: The study aims to examine recent transformations in rural habitats undergoing depopulation in Aragón, Spain, between 2010 and 2018. It seeks to verify changes in habitat concentration patterns and identify the underlying factors. Theoretical Framework: Drawing upon theories of rural exodus and demographic shifts, the research employs the Colas Index (Colas, 1945) to analyze habitat types—dispersed or concentrated. It recognizes the influence of agricultural changes, service provision challenges, and territorial dynamics on rural settlement patterns (Escolano and de la Riva, 2003; Nuninger et al., 2021). Method: The investigation focuses on depopulated municipalities in Aragón, utilizing a comparative analysis of the Colas Index from 2010 to 2018. Administrative boundaries define the study's territorial units, enabling the quantification of habitat changes and an assessment of their direction. The analysis integrates demographic and settlement dynamics to understand habitat evolution. Results and Discussion: Findings indicate varied habitat transformation processes across municipalities, confirming the heterogeneity of the rural landscape (Pinilla and Sáez, 2017). While transformations are not universal, they challenge the traditional link between depopulation and habitat concentration. The Colas Index proves valuable for characterizing habitat dispersion levels, yet its limitations in concentrated areas are acknowledged. Methodological constraints related to administrative boundaries and the complexity of rural-urban continua are also discussed. Research Implications: This study contributes to a nuanced understanding of depopulation impacts on rural habitats, informing territorial planning and demographic policies. It underscores the need for tailored strategies that consider local habitat variability and the potential for revitalization efforts in select areas. Originality/Value: By highlighting the diversity of habitat transitions amidst depopulation, the research offers fresh insights into rural settlement dynamics. Its value lies in demonstrating that depopulation no longer universally leads to habitat concentration, thus updating the scholarly discourse on rural transformation in Spain.

Adaptation in the Anthropocene: How behavioural choice and colour change enables chameleon prawns to camouflage on non-native seaweeds.

Animals combine colour change and behavioural choices to enhance concealment and adapt to changes in habitat in time and space. However, non-native and invasive habitat-forming plants and seaweeds can change the landscape, challenging animals to remain camouflaged, especially when the colour of the new habitat differs from the native backgrounds.The chameleon prawn (Hippolyte varians) exhibits remarkable colour variation and effective camouflage against different native seaweeds in shallow tidepools. Individuals optimize crypsis by choosing colour-matching seaweeds and changing colour over time. In some locations, the prawn's native habitats are now replaced by non-native seaweeds of different coloration and structure, making it important to understand whether substrate choice and colour change facilitates the occupation of these seaweeds and enables prawns to camouflage against new backgrounds.Using image analysis and visual modelling of a fish predator, we assessed the colour variation and camouflage of chameleon prawns occupying the non-native seaweeds brown wireweed (Sargassum muticum) and pink harpoon weed (Asparagopsis armata) in southwest UK. We performed laboratory trials to examine whether prawns maintain their preference for colour-matching native substrates when given a choice between them and non-native seaweeds, and if they can change their coloration to improve camouflage against non-native substrates.Prawns exhibit phenotypic diversity and camouflage that varied with the non-native seaweed species, with low colour variation and effective camouflage on pink harpoon weed, but high colour diversity and reduced concealment against brown wireweed. Prawns choose non-native seaweeds when the alternative native substrate provides mismatching coloration, but they did not exhibit any preference between colour-matching native and non-native seaweeds. Once in non-native habitats, prawns change their appearance over a few days to match the background, sometimes faster than when changing on native seaweeds of contrasting coloration.Although human activities considerably modify the coloration of marine landscapes by increasing the establishment of non-native seaweeds, the impacts of those changes appear less severe for colour-changing species, such as chameleon prawns, and will depend on the similarity between the colour of the new substrates and the original native backgrounds, and how animals use behaviour and physiology to match new habitats.

Enhancing Ecological Education: Utilizing Agent-Based Modeling to Simplify the Impacts of Deforestation on Amphibians

Understanding how deforestation and changes in habitat boundaries affect biodiversity is essential for developing conservation solutions. These topics are central to biology and ecology programs, where students learn to apply their knowledge in real-world conservation efforts. Higher education plays a crucial role in strengthening this understanding, particularly in life sciences programs. Given the complexity of ecological processes in altered landscapes, agent-based modeling provides an interactive and engaging way to simplify and visualize the effects of land use changes. In this study, we integrate Amazonian anurans, highly sensitive to temperature and humidity fluctuations, with an Agent-based model to simulate the impacts of deforestation, habitat restoration, and land abandonment on species survival and movement. Their ectothermic nature and dependence on pulmocutaneous respiration make them especially vulnerable to the drier and more variable conditions caused by deforestation. Integrating this model into conservation biology courses has enhanced learning by encouraging independent exploration, both in and out of the classroom. This tool, an agent-based model, is particularly suited for university-level ecology and conservation courses, and can also serve as an effective awareness tool in environmental education and decision-making workshops, highlighting the negative effects of human-made habitat changes on biodiversity.

Population estimate and habitat association of Grant’s gazelle (Nanger granti Brooke, 1872) in the Ene Forest of Dale Sadi district, western Ethiopia

Grant’s gazelles (Nanger granti) are classified as of least concern by the IUCN, although their number is declining due to several factors. A few research studies have been conducted on Grant’s gazelle in Ethiopia. Thus, the present study was carried out to determine the population size and habitat association of Grant gazelle in the Ene Forest of western Ethiopia, comprising the dry and wet seasons. The study area was stratified into four habitats: woodland, mixed woodland, riverine forest, and grassland habitats. The data were collected using the direct observation technique. The data were analyzed using descriptive statistics and Pearson’s chi-square (χ2) test. The average estimated Grant gazelle population was 136 ± 23 individuals, with a density of 9/km2. The adult male-to-adult female sex ratio was 1:1.40 and 1:1.26 during the wet and dry seasons, respectively. The largest herd size (N = 6) was observed during the wet season, and the smallest (N = 4) was observed during the dry season. The highest numbers of Grant gazelles were observed in the grassland habitat during the wet season and in the woodland during the dry season. More Gazelles (N = 65) were observed in the woodland habitat compared to the other habitat types. The continued existence of the Grant’s gazelle population in the area and the suitability of the environment depend significantly on ongoing assessments of habitat change and management intervention.

Playback-Aided Surveys and Acoustic Monitoring in the Detection of the Endangered Forest Owlet Athene blewitti.

Monitoring rare and endangered species over the long term is challenging due to limited historical data and comparable methods. Climate and landscape changes can significantly impact species distributions, driving some to extinction. The Forest Owlet is an endangered bird considered extinct but rediscovered after 113 years in 1997. Since its rediscovery, followed by the description of its calls, there have been regular recent sightings of the species from newer locations, leading to its downlisting in the IUCN Red List from critically endangered to endangered. In the Dang region in Gujarat, India, there have been no historical records despite previous systematic ornithological studies over three decades, but have multiple sightings over the last few years. Although we now know a little more about the broad association of the species occurrence with habitat and climate variables, a major focus of this study is to estimate the reasons for the "appearance" of the Forest Owlet in Dangs. We revisited locations of past surveys to determine if the species is currently found in the study sites where it was previously unrecorded. We also examine whether new survey methods using playback of its call could enhance its detection. During resurveys, we located the Forest Owlet at new, previously unrecorded locations. Analyses of satellite imagery products revealed significant changes in the broader Dang landscape, including the loss of native forests, increased agriculture, and shifts in mean maximum temperature and rainfall. Our research suggests playback can enhance detection, although its effectiveness varies across landscapes. A detection strategy for long-term monitoring was developed using different acoustic detectors. An effective detection distance of 300 m within the habitat was achieved using automated recording units (ARUs). Although the species responds to climate and habitat change, the cause of the increased reports of this endangered species remains undetermined. However, we found increased detections using newer survey techniques involving bioacoustics. We recommend using these techniques carefully for future baseline studies, which are urgently required.

Full life cycle assessment of insect biomass allows estimation of bioflows across water, air, and land

AbstractAs global environmental change continues, animals face uncertain habitat availability and quality that influences life cycle phenology and population dynamics. For decades, the population abundance and emergence patterns of burrowing mayflies have been used as a sentinel for water quality changes in large freshwater systems around the world. Despite reduced point source pollutants, evidence is mounting that the interactions among habitat loss, contaminants, and changing climate could be causing declines in mayfly production and shifts in emergence timing. We combined radar observations with traditional field measures to identify changes in mayfly populations from nymph to adult. We studied Hexagenia sp. secondary production in a large reservoir, Lake Seminole, which has contrasting water sources and land use on each arm that could contribute to differences in emergence patterns. We predicted that mayfly secondary production would be higher, and emergence would be earlier in the Chattahoochee arm versus the Flint arm because of differences in available nutrients and temperature. Benthic declines in abundance and biomass followed radar observations of emergence. Mean annual water temperature was similar, with the Flint arm having less seasonal variation. Mayfly growth was similar across the lake, but production was higher in the upper Flint arm, perhaps because of temperature stability, higher nutrient concentrations, and more lotic conditions. The natural abundance of nitrogen‐stable isotopes in mayflies showed distinct patterns between the arms and from nymph to adult. Linking benthic sampling with radar observations verified our capability to track mayfly biomass across the landscape and begin to calibrate previous measures of production with radar‐derived abundance. Coupling radar observations with stable isotope and tissue nutrient measurements allowed us to further quantify the subsidies moving from aquatic to terrestrial ecosystems, setting the framework to examine both historic and future population changes and mayfly contributions to cross‐ecosystem subsidies.

Prevalence and diversity of spotted fever group Rickettsia species in ixodid ticks from domestic dogs in Chad, Africa

Tick-borne pathogens in the genus Rickettsia are the causative agents of severe and potentially fatal spotted fever group (SFG) and typhus group diseases in dogs and humans. Climate, habitat, and land-use changes are impacting vector ranges, with expansions potentially resulting in novel pathogens being introduced into naïve locations. Despite the public health importance of SFG Rickettsia, there are relatively few data on the prevalence and diversity of rickettsial pathogens in sub-Saharan Africa. The aim of this study was to characterize the SFG Rickettsia prevalence and diversity in ixodid ticks (104 Amblyomma spp., 160 Rhipicephalus spp., and one Hyalomma truncatum) collected from domestic dogs in Chad, Africa. Ticks were screened for Rickettsia spp. using a nested PCR targeting the 17-kDa gene. Species identification was through bidirectional Sanger sequencing of the 17-kDa, ompA, ompB, and/or gltA gene targets. A total of 43.3 % (115/265) ticks were positive for Rickettsia spp. and six Rickettsia species were identified: R. africae, R. massiliae, R. conorii, R. felis, R. monacensis and Candidatus Rickettsia muridii. Seven additional samples were positive for Rickettsia of undetermined species. Rickettsia africae, an important zoonotic pathogen, was found in 81 % (79/97) of A. variegatum and 29 % (2/7) of an A. marmoreum complex species, a group that infests a wide range of birds and mammals, including humans. Finally, we detected a high diversity of Rickettsia spp., most of which were zoonotic, in Rh. muhsamae. Collectively these data indicate there is a risk of rickettsiosis in Chad and further studies on ticks and rickettsial pathogens in this region are warranted.

Predicting Changes in Potential Habitats of an Endemic Plant Species under SSP Scenarios: A Case Study of <italic>Eranthis byunsanensis</italic>

Background and objective: Climate change significantly impacts the growth environments of organisms that have adapted to natural environments. Endemic plants, which are native to specific regions, are particularly vulnerable to these changes. The conservation of these plants is a crucial national task. Currently, there is a lack of research on the habitat characteristics and conservation measures of specific species in Korea. This indicates a need for systematic research on field surveys of habitats for valuable species, the establishment of environmental variables, and long-term changes in suitable habitat areas. Therefore, this study aimed to identify the geographical distribution characteristics and select the optimal environmental variables for Eranthis byunsanensis, an endemic plant in the Korean Peninsula.Methods: To achieve this, we utilized an ensemble model in the R package biomod2 to analyze the current potential habitat and understand its distribution characteristics. We then predicted the changes in potential habitats for the mid-future (2041-2070) and the long-term future (2071-2100) based on climate change scenarios (SSP 1-2.6 and SSP 5-8.5). Finally, we conducted a comparative analysis of the differences between the scenarios.Results: Long-term projections indicate that potential habitat area is larger under SSP1-2.6, a scenario with active climate change mitigation policies, than under SSP5-8.5. Under SSP1-2.6, habitat remained relatively stable with expansion observed in coastal Gangwon-do. In contrast, SSP5-8.5, characterized by extreme climate change, led to significant habitat decline in Jeollabuk-do. Inland Jeollabuk-do experienced rapid habitat loss with a northeastward shift, while habitat along the East Sea coast of Gangwon-do expanded.Conclusion: This study's analysis of habitat change can serve as a crucial foundation for the conservation and management of endemic plants. Furthermore, it is expected to contribute to the development of response strategies to climate change and the identification of alternative habitats for endemic plants.

The Adaptive Mechanism of Ginseng Rhizomes in Response to Habitat Changes

Panax ginseng, a perennial medicinal plant, utilizes its dried roots and rhizomes for medicinal purposes. Currently, in China, ginseng cultivation employs two methods: under-forest and farmland planting. These methods create distinct habitats, significantly influencing the ginseng’s rhizome morphology and, consequently, its economic value. In this study, two-year-old ginsengs were transplanted into farmland (TCG), a larch forest (TLCG) and a Quercus mongolica forest (TQCG) to analyze the differences in rhizome phenotypes caused by habitat changes. The results showed that there were significant differences in light intensity and the soil’s available phosphorus and potassium contents between farmland and forest environments. The differences in habitats led to different adaptability of the ginseng’s rhizome morphology. Compared with TCG, the rhizomes of TLCG and TQCG were significantly elongated by 48.36% and 67.34%, respectively. After the rhizomes’ elongation in TLCG and TQCG, there was an increase in indole-3-acetic acid (IAA) contents and a decrease in lignin contents. By analyzing the expression of key genes, we found that, compared with TCG, the expression of key enzymes of lignin biosynthesis genes such as PgCOMT and PgCCR4 were down-regulated. The difference in ginseng’s rhizome length is related to the signal transduction pathway of auxin and gibberellin. In addition, we preliminarily screened out transcription factors PgWRKY75, PgDIV, and PgbHLH93.1, which can actively respond to habitat changes and play important roles in the elongation of ginseng rhizomes. In summary, this study elucidates the phenotypic plasticity strategy of ginseng rhizomes in response to habitat changes and delineates the regulatory mechanism behind phenotypic adaptation, offering novel insights into ginseng’s morphogenesis.

A Genomic Exploration of the Possible De-Extirpation of the Zanzibar Leopard.

The recently extirpated Zanzibar leopard was the only known African leopard (Panthera pardus spp.) population restricted exclusively to a major island habitat. Although its demise was driven through habitat change and conflict with humans, given its role as a keystone species for the Zanzibar Archipelago, its successful potential reintroduction might offer a means for helping preserve the natural biodiversity of its former habitat. Whether this is feasible, however, would be contingent on both whether closely related source populations can be identified on mainland Africa, and whether the Zanzibar form exhibited any special adaptations that might need to be considered when choosing such a source. In light of these questions, we genomically profiled two of the six known historic specimens, to explore whether they represent a realistic candidate for de-extirpation through reintroduction. Our analyses indicate that despite its geographical separation, the Zanzibar leopard shared a close genetic relationship with mainland East African individuals. Furthermore, although its uniqueness as an island population was emphasised by genomic signatures of high inbreeding and increased mutation load, the latter similar to the level of the critically endangered Amur leopard (P. p. orientalis), we find no evidence of functionally significant genetic diversity unique to Zanzibar. We therefore conclude that should attempts to restore leopards to Zanzibar be considered, then mainland East African leopards would provide a suitable gene pool.

New Approaches for Regeneration of an Outstanding Baroque Living Heritage, the Széchenyi Linden Allée in Hungary

Allées used to be the essential artistic tools and indispensable parts of the strictly architectural, formal Baroque gardens. Beyond the practical purposes of edging paths and garden ways for walking, hunting, or horse and carriage riding, allées played a vital role in marking visual and landscape connections and thus the spatial projection of the noble estate, its wealth, and social rank. In Historical Hungary, Baroque architecture and garden art appeared in German-Austrian and French examples in the 18th century. The Széchenyi Linden Allée is an outstanding linear garden space of Baroque Garden art at Nagycenk, West Hungary. The generous composition, created by the prominent Count Széchenyi family in the mid-18th century, has remained a magnificent entity in the landscape ever since. Despite barely two hundred years of detected or unknown environmental or habitat changes, as early as 1942, the allée received a nature conservation nomination. More than a half-century later, in 2002, the allée became a historical and landscape aesthetical heritage within the Fertő-Hanság Cultural Landscape World Heritage site. Unfortunately, the once magnificent tree lines have severely eroded in recent decades due to mature trees’ subsequent death, inadequate replacement, lack of regular maintenance and tree care, and effects of climate change. In recent years (2011, 2018), landscape and horticultural analyses and visual and instrumental tree assessments were performed to help the conservation and rebirth of the allée, maintain the mature trees, and restore the landscape within a long-term renewal plan. Along with the 2018 survey and plan, the short-term maintenance works were completed in 2019–2020. This study, based on site surveys in 2022 and 2024, aims to identify the results of the primary management, analyses the vitality of mature trees after crown reductions, and then proposes a resilient and sustainable regeneration method with the habitat, cultural, natural, and genetic heritage, and the feasible maintenance contexts in focus. As proposed in the 2018 plan, the reproduction of mature trees started in 2020 and resulted in well-developing grafts for a later allée restoration. Due to the challenges of climate change, the regeneration project requires a special, long-term restoration management plan with a special focus on the still vital and possible remaining mature trees, the well-growing individuals from previous replanting, and the nursery school seedlings conserving the genetic heritage of the Széchenyi lime trees with long-viability capacity.

Nature-based solutions: estuarine restoration for water quality, seagrass and ecological improvement

Natural ecosystems are marked by complex interconnections and a high degree of resilience and adaptability. Historically many of these areas have been viewed as an obstacle to be cut down, channelized and drained for development. Such development in turn requires catchment based local stormwater management systems that do not scale with climate change and focus on only one element such as flood control or water quality. These traditional, localized approaches to water fail to take advantage of the interconnected benefits of nature-based systems and approaches to water management. These benefits include ecological uplift, enhanced habitat, eco-tourism, recreation, carbon sequestration and climate change resilience. There is a notable shift towards utilizing nature-based solutions to work with development and water management as evidenced by emerging government policy, funding and permitting requirements as well as the number of examples of recent successful projects. This paper examines one such project, a new tidal connection through the SR 60/Courtney Campbell Causeway in an estuarine area of Old Tampa Bay, Florida, United States. The connection was established to improve water quality in an area north of the causeway isolated by highway development and infill. Based on recent monitoring data, the project significantly improved water quality and ecological conditions conducive to seagrass recovery and increased biodiversity.

Status Keberlanjutan Program Pelepasliaran Orangutan Sumatera (Pongo abelii L.) di Bentang Alam Bukit Tiga Puluh Provinsi Jambi

This research aims to analyze the sustainability status and analyze sensitive attributes (leverage analysis) on the sustainability of the Sumatran orangutan (Pongo abelii L.) reintroduction program in the Bukit Tigapuluh Landscape. The analysis was carried out using the RAPFISH method with four dimensions, namely ecological, economic, social and institutional dimensions which were then validated using the Monte Carlo method, determining the stress value and R2 value. Determining sensitive attributes is done using leverage analysis. The research results show that the sustainability status of the Sumatran Orangutan (Pongo abelii L.) reintroduction program in the Bukit Tigapuluh Landscape in the ecological and economic dimensions is quite sustainable, but in the social and institutional dimensions it is less sustainable. The results of the sensitivity analysis showed that of the total of 36 attributes used, 13 sensitive attributes were identified which influenced the sustainability index value of the Sumatran orangutan reintroduction program namely pressure on the area, number and type of nest trees, forest area area, opportunities for competition (intra and between species), level of habitat suitability, contributing to improving the community's economy, average income against UMP, potential tourist attractions, threat of habitat change, conflict management mechanisms, threat of animal hunting, level of community education and information on regulations related to management rules for Sumatran orangutans.

The ‘Climate Adaptation Problem’ in Biodiversity Conservation: The Value of Spatial Flexibility in Land Purchase

AbstractExisting reserve networks become less suitable as species’ ranges shift under climate change and the scarcity and value of habitats change. Reserve sites hence have to be reallocated to reflect these changing values and to remain cost-effective, but restrictions on selling reserve sites limit this adaptation. Under climate change, a novel ‘sale’ policy that provides resale flexibility by allowing increasingly less cost-effective sites to be sold to free funds for purchasing increasingly cost-effective sites may hence be preferable over a typical ‘no sale’ policy. Here, we develop a conceptual climate-ecological-economic model to examine under what conditions resale flexibility provides cost-effectiveness advantages. We find that the benefits of resale flexibility provided by the ’sale’ policy are particularly high when little funding is available for climate change adaptation. Due to this budget effect, the value of resale flexibility also decreases with increasing interest rates. The value of resale flexibility is particularly high when creating reserves for species that are highly mobile as new reserve sites may then be chosen freely (in comparison to the case that new sites have to be located in the proximity of existing reserve sites). We further examine to what extent the ‘sale’ policy reduces the permanence of habitat within a specific location (“site habitat permanence”), and identify a new trade-off: ’sale’ provides advantages for habitat types that become increasingly rare, while ’no sale’ improves site habitat permanence mainly for expanding habitat types.

Growing older, growing more diverse: Sea turtles and epibiotic cyanobacteria.

Cyanobacteria are known for forming associations with various animals, including sea turtles, yet our understanding of cyanobacteria associated with sea turtles remains limited. This study aims to address this knowledge gap by investigating the diversity of cyanobacteria in biofilm samples from loggerhead sea turtle carapaces, utilizing a 16S rRNA gene amplicon sequencing approach. The predominant cyanobacterial order identified was Nodosilineales, with the genus Rhodoploca having the highest relative abundance. Our results suggest that cyanobacterial communities become more diverse as sea turtles age, as we observed a positive correlation between community diversity and the length of a sea turtle's carapace. Since larger and older turtles predominantly utilize neritic habitats, the shift to a more diverse cyanobacterial community aligned with a change in loggerhead habitat. Our research provides detailed insights into the cyanobacterial communities associated with loggerhead sea turtles, establishing a foundation for future studies delving into this fascinating ecological relationship and its potential implications for sea turtle conservation.

Northern bobwhite (Colinus virginianus) population response to anthelminthic treatment in the Rolling Plains ecoregion of Texas, 2014–2016

Northern bobwhite quail (Colinus virginianus) are an economically significant gamebird that has experienced continued general decline in the Rolling Plains ecoregion of Texas. Habitat loss and changing environmental conditions have been cited as major contributors to this decline, with factors such as parasites being considered inconsequential. To better assess the impacts of parasite infections on bobwhite populations in the Rolling Plains, bobwhite abundance was monitored in response to anthelminthic treatment. With the prevalence of Oxyspirura petrowi and Aulonocephalus pennula infections in quail from Mitchell County, Texas confirmed by previous studies, the anthelminthic agent Fenbendazole was introduced as a means of parasite control in 2014–2015. Bobwhite abundance was determined through a series of call counts which provided an index of bobwhite populations and were conducted throughout the course of the study. In 2016, call counts revealed a significant increase of bobwhite in the area subject to Fenbendazole treatment, while untreated areas showed no changes in abundance. Fall populations of bobwhite in the treated zone approached 300% of those in untreated areas, these findings suggest that parasites may have a more significant impact on quail populations in the Rolling Plains than previously suspected. With the importance of bobwhite as a game bird in the Rolling Plains, the potential impacts of parasites must be taken into consideration as a factor contributing to bobwhite declines. Further research into the long-term effects these parasites have on quail populations in the ecoregion may aid landowners in developing affordable and effective conservation strategies.

The economic impacts of living habitat changes in the Virginia Middle Peninsula, Chesapeake Bay

Living habitats support ecologically and commercially important species but are threatened by anthropogenic stressors, including climate change. The populations of two living habitats in the Chesapeake Bay, Eastern Oyster (Crassostrea virginica) and Eelgrass (Zostera marina), are depleted compared to historical levels, but recent Oyster restoration efforts have created new reef habitat and enhanced existing Oyster reefs. Other animals (e.g., commercially important fish and invertebrates) consume organisms that associate with these living habitats, suggesting the regional economies that rely on the commercial fishing industry may be impacted by changes in living habitat coverage. Ecosystem models were developed for two rivers that have undergone Oyster restoration in the Virginia Middle Peninsula, and simulations were conducted to estimate the potential influence that changes to living habitats may have on commercial fisheries harvests. Additionally, commercial fishers were interviewed to document expenditures needed to link ecological model estimates to an economic input-output model via IMPLAN that estimated the regional economic impacts of these changes. Increases to Oyster and Eelgrass populations are predicted to enhance commercial fisheries populations and in turn, harvests, while decreases to living habitats are predicted to have negative effect on fisheries harvests. The driving factor behind landed value trends is changes with the lucrative Blue Crab (Callinectes sapidus) fishery. The primary expenses of watermen are repairs/maintenance, fuel, and bait, but greater than 37 % of the annual revenue is retained as proprietor and crew income. Oyster reef restoration alone is predicted to increase the regional economic impact of the commercial fishing industry by $1.1 M yr-1 and support 12 more full-time jobs at the end of a 20-year simulation. Oyster restoration in combination with a continued decline of Eelgrass led to a negligible increase (∼$150 K yr-1) in the regional economic impact. Eelgrass restoration to the current management goal without the influence of Oyster restoration is anticipated to elevate the regional economic impact to $16.8 M yr-1 and 152 full-time jobs, and smaller increases to the Eelgrass population, relative to current levels, will still have a positive impact on the regional economy. Combined Oyster and Eelgrass restoration are predicted to enhance economic impacts to the greatest extent, while continued Eelgrass decline is likely to minimize these benefits.