Suitable Habitat Research Articles

Hypoxia influences the extent and dynamics of suitable fish habitat in Chesapeake Bay, USA

Intra-annual patterns of hypoxia in Chesapeake Bay have been recorded since the mid-1900s, but anthropogenic inputs and climate change have exacerbated the volume and extent of hypoxic waters, which mobile marine fishes avoid. This estuary provides important habitat for many seasonally resident species but declines in relative abundance and relative habitat usage have been documented. An understanding of the relationship between environmental conditions and habitat suitability could assist in evaluating the stock status of these species. To characterize baseline habitat associations for Micropogonias undulatus, Leiostomus xanthurus, Paralichthys dentatus, and Cynoscion regalis, ecological niche models were developed relating catch-per-unit-effort data from a fisheries-independent trawl survey conducted within Chesapeake Bay to environmental covariates. Model output indicated that impacts of climate change on the environmental conditions, including continued increases in temperature and decreases in dissolved oxygen (DO) concentration, will likely further the decline in estuarine utilization of these species. The niche envelopes were then paired with hindcasts from an estuarine-carbon-biogeochemical regional model to derive estimates of spatiotemporal habitat suitability. The patterns in habitat suitability do not match those of declining abundance, indicating that dynamics outside of Chesapeake Bay are likely driving the shift. An auxiliary model was used to replace hypoxic DO concentrations with normoxic concentrations to evaluate the influence of hypoxia on habitat suitability. Both hypoxic severity and extent displayed significant associations with the quantity of suitable habitat available to each species in the bay. Results characterize the complexity of the dynamics underpinning observed trends in habitat utilization.

Integrated approach to predicting habitat suitability and evaluating quality variations of Notopterygium franchetii under climate change.

The impact of climate change on medicinal plants has significantly altered their suitable environments, thereby affecting the quality of herbal medicines. Notopterygium franchetii (N. franchetii), a medicinal plant intricately linked to its natural habitat, exhibits substantial quality variations influenced by the ecological conditions of its native region. In this study, comprehensive field surveys were conducted to gather occurrence records and samples of N. franchetii. The Maxent model and ArcGIS software were employed to predict the suitable habitats of N. franchetii during different time periods. A high-performance liquid chromatography (HPLC) method was developed to establish the chemical fingerprints of 21 sample batches. Fourteen common peaks were subjected to cluster analysis, principal component analysis, and orthogonal partial least squares-discriminant analysis. The findings revealed quality variations correlated with their geographic origins, identifying peaks 10, 1, 14, 3, and 4 as crucial for quality differentiation. The study indicates that precipitation, temperature, and altitude significantly influence the distribution of N. franchetii. Under current climate conditions, the suitable habitat area for N. franchetii is estimated to be approximately 94,637.33 km2. However, projections under three future climate scenarios suggest a declining trend in suitable habitat areas. A quality zoning map of N. franchetii was developed, integrating a correlation model between chemical composition and environmental variables with the spatial analysis and visualization capabilities of ArcGIS. The high-quality regions for N. franchetii are predominantly located in the Gannan, Linxia, Dingxi, Longnan, and Wuwei districts. These research outcomes offer a valuable reference for identifying suitable cultivation areas and assessing the quality of N. franchetii in Gansu Province.

The effects of seasonal human mobility and Aedes aegypti habitat suitability on Zika virus epidemic severity in Colombia.

The Zika virus epidemic of 2015-16, which caused over 1 million confirmed or suspected human cases in the Caribbean and Latin America, was driven by a combination of movement of infected humans and availability of suitable habitat for mosquito species that are key disease vectors. Both human mobility and mosquito vector abundances vary seasonally, and the goal of our research was to analyze the interacting effects of disease vector densities and human movement across metapopulations on disease transmission intensity and the probability of super-spreader events. Our research uses the novel approach of combining geographical modeling of mosquito presence with network modeling of human mobility to offer a comprehensive simulation environment for Zika virus epidemics that considers a substantial number of spatial and temporal factors compared to the literature. Specifically, we tested the hypotheses that 1) regions with the highest probability of mosquito presence will have more super-spreader events during dry months, when mosquitoes are predicted to be more abundant, 2) regions reliant on tourism industries will have more super-spreader events during wet months, when they are more likely to contribute to network-level pathogen spread due to increased travel. We used the case study of Colombia, a country with a population of about 50 million people, with an annual calendar that can be partitioned into overlapping cycles of wet and dry seasons and peak tourism and off tourism seasons that drive distinct cyclical patterns of mosquito abundance and human movement. Our results show that whether the first infected human was introduced to the network during the wet versus dry season and during the tourism versus off tourism season profoundly affects the severity and trajectory of the epidemic. For example, Zika virus was first detected in Colombia in October of 2015. Had it originated in January, a dry season month with high rates of tourism, it likely could have infected up to 60% more individuals and up to 40% more super-spreader events may have occurred. In addition, popular tourism destinations such as Barranquilla and Cartagena have the highest risk of super-spreader events during the winter, whereas densely populated areas such as Medellín and Bogotá are at higher risk of sustained transmission during dry months in the summer. Our research demonstrates that public health planning and response to vector-borne disease outbreaks requires a thorough understanding of how vector and host patterns vary due to seasonality in environmental conditions and human mobility dynamics. This research also has strong implications for tourism policy and the potential response strategies in case of an emergent epidemic.

Forecasting Suitable Habitats of the Clouded Leopard (Neofelis nebulosa) in Asia: Insights into the Present and Future Climate Projections Within and Beyond Extant Boundaries

Terrestrial carnivores, such as the clouded leopard (Neofelis nebulosa), are ‘vulnerable’ and experiencing significant population declines in mainland Asia. Considering the assessed threats, the IUCN has repetitively revised the range of this felid and now characterized it into four distinct categories (extant, possibly extant, possibly extinct, and extinct). Although several ecological works have been accomplished on this enigmatic carnivore, the overall view of its habitat suitability, fragmentation, and corridor connectivity in both present and historical ranges is lacking. Thus, achieving this ecological information under present and future climate scenarios is crucial. The model identified merely 44,033 sq. km falling within the extant range (representing 31.66%) and 20,034 sq. km (8.13%) in the possibly extant range. Fascinatingly, within the historical ranges, an additional 15,264 sq. km (6.58%) has been identified as suitable habitat in the possibly extinct range and 14,022 sq. km (2.38%) in the extinct range. Notably, a total of 25,614 sq. km of suitable habitat is found within designated protected areas across the entire range. Nevertheless, climate change is expected to drive habitat loss of up to 41% (overall IUCN range) for N. nebulosa in both present and historical extent, with habitat patches becoming increasingly fragmented. This is reflected in a projected decline in the number of viable habitat patches (NP) by up to 23.29% in the future. This study also identified 18 transboundary biological corridors for N. nebulosa, with Southeast Asian countries expected to experience the most significant declines in corridor connectivity. In contrast, the South Asian countries (Bhutan, Nepal, and India) are projected to maintain relatively higher connectivity in the future. Nevertheless, a substantial decline in overall mean corridor connectivity is projected in the near future due to the impacts of climate change. This study underscores the urgent need for a coordinated and multifaceted conservation strategy for N. nebulosa, focusing on mitigating habitat loss and fragmentation. Practical measures must be implemented to protect the species’ shrinking range, considering its declining corridor networks and heightened vulnerability to inbreeding depression. Moreover, the assessment of habitat suitability both within and beyond the extant range, alongside corridor connectivity measures, provides valuable insights into potential translocation and reintroduction sites for this species. These findings provide a critical foundation for developing a strategic conservation plan tailored to the specific needs of this felid species across South and Southeast Asia, ensuring enhanced climate resilience and mitigating associated threats.

Grading Habitats for Ticks by Mapping a Suitability Index based on Remotely Sensed Data and Meta® population dataset in Aosta Valley, NW Italy.

Ticks represent a reservoir of zoonotic pathogens, and their numbers are increasing largely in wildlife. This work is aimed at producing maps of suitable habitats for ticks in Aosta Valley, Italy based on multitemporal EO data and veterinary datasets (tick species and distribution in wild hosts). EO data were processed in Google Earth Engine considering the following inputs: A) Growing Degree Ticks (GDT), B) NDVI from MOD09GA, C) NDVI entropy, D) distance from water bodies, E) topography, F) rainfalls from CHIRPS as monthly composites along the 2020, 2021 and 2022 years. Ticks were collected from hunted, injured, and found-dead wild animals ( Sus scrofa, Capreolus capreolus, Rupicapra rupicapra, Cervus elaphus); they were labeled at species level using taxonomic keys. Between September 2020 and December 2022, a total of 90 ticks were collected from 89 wild animals. Ixodes ricinus was the most prevalent tick species, followed by Dermacentor marginatusand Dermacentor spp. Molecular analyses demonstrated the presence of Anaplasma spp., B. burgdorferi sensu lato and Rickettsia spp. pathogens in infected ticks. To assess human population potential exposure to tick Meta® population dataset was used. In conclusion this study shows the potentialities of Remote sensing improving the technological transfer to the veterinarian sector.

Shifts in the habitat suitability for large hammerhead sharks under climate change

One of the chief consequences of climate change is the worldwide redistribution of species in the pursuit of physiologically and ecologically favourable conditions. As part of one of the most threatened groups of vertebrates, assessing how climate change may affect the distribution patterns of key shark species is essential for their long-term conservation and management. The present study aims to assess how climate change projections (based on the representative concentration pathways 2.6, 4.5, 6.0, and 8.5) for the middle and end of the century may affect the global patterns of habitat suitability (HS) for large hammerhead sharks – a unique and particularly threatened group of elasmobranchs. Here, a decline in the global average HS is projected for both Sphyrna lewini and Sphyrna zygaena, with the scale of HS decline generally increasing with time and RCP severity, while a global increase in HS is generally projected for Sphyrna mokarran, albeit reduced over the long-term and overturned under long-term RCP8.5. Meanwhile, poleward shifts are projected for all three species, with considerable tropical declines for both S. lewini and S. zygaena. Additionally, regional shifts in suitability have the potential to affect population connectivity, the access to key habitats, and levels of exposure to other anthropogenic pressures, along with the effectiveness of conservation and management efforts. Taken together, these results showcase the importance of climate change for species’ extinction risk assessments and the urgency of the consideration of climate change within the design and implementation of conservation measures.

Barn Owls as a Nature-Based Solution for Pest Control: A Multinational Initiative Around the Mediterranean and Other Regions

Pest rodents cause extensive damage to crops worldwide. Up to 40% of global crop production is lost annually to pests and diseases, with rodents accounting for 15–30% of this loss amounting to billions of dollars each year. The current method of controlling rodent populations involves the extensive use of chemical rodenticides. While effective in the short term, these chemicals pose serious environmental and health risks, leading to secondary poisoning of non-target species and other long-term negative ecological consequences, underscoring the need to adopt more sustainable pest-control measures. Nature-Based Solutions (NbSs), on the other hand, are increasingly recognized for addressing environmental challenges such as climate change, biodiversity loss, and sustainable development, and they include actions that protect, sustainably manage, and restore ecosystems. In this context, Barn Owls (Tyto alba) are highly effective as a natural pest-rodent control agents in agro-ecosystems. The species has a wide distribution and adaptability to various environments, and its diet consists predominantly of small mammals, with rodents making up from 50–60% up to even 90–95% of the diet according to different geographical regions. Each Barn Owl family can consume thousands of rodents annually, creating a high potential to reduce crop damage and infestations. Deploying nest boxes in agricultural areas can significantly increase Barn Owl populations, ensuring continuous and effective rodent control. Limitations of this solution must also be taken into consideration such as predation on rodents and small mammals that are not pests, and possible competition with other nocturnal birds of prey. Ιn the current paper, we aim to introduce the concept of owls as a NbS for pest rodent control and outline the main challenges, pitfalls, advantages, and disadvantages of implementing this solution in a new geographical region, and all the necessary in-between steps (scientific, societal, administrative, educational) that have to be followed for a successful implementation. So far, several countries have successfully implemented Barn Owl nest box schemes, with Israel and Cyprus achieving reduction in the use of pesticides by 45% and 58%, respectively, whereas the project is spreading to other Mediterranean countries (Jordan, Palestine Authority, Greece, Morocco, Spain), in palm plantations in Malaysia and USA, and in the vineyards of Napa Valley in California. The success of Barn Owl nest box programs relies on integrating scientific research, societal needs, supportive policy frameworks, and education. Barn Owl nest box programs are both bottom-up and top-down initiatives, in need of the participation of farmers and local communities to establish and deploy the Barn Owl solution. Continuous research is also necessary to explore systematically Barn owl trophic ecology, foraging and breeding ecology, interactions with agricultural landscape, and land uses in temporal and spatial scales, and challenges such as habitat suitability, availability of nesting sites, and regional ecological conditions must also be addressed.

Current conservation status and potential distribution under climate change of Michelia lacei, a Plant Species with Extremely Small Populations in Yunnan, China

Abstract Michelia lacei W.W. Smith, a magnolia species categorized as Endangered on the IUCN Red List, is subject to severe disturbance. We carried out field surveys and a review of literature records to present a detailed description of the current status of M. lacei. We then predicted the potential distribution of M. lacei under different climatic scenarios based on 60 occurrence records (53 recorded during our field surveys and 7 earlier records) and 19 bioclimatic variables from the WorldClim database. We selected 18 locations and four bioclimatic variables for model training. Temperature seasonality and annual temperature range were the most influential variables for predicting the potential distribution of the species. We used MaxEnt to model distribution under current climate conditions and four Shared Socioeconomic Pathway scenarios in four future time periods to determine the effects of future climate change on the habitat suitable for the species. We predict areas of moderately and highly suitable habitat will gradually decrease over time. We recommend increased in situ and ex situ conservation efforts to mitigate this habitat decline and protect populations of M. lacei.

Genomic Vulnerability to Climate Change of an Australian Migratory Freshwater Fish, the Golden Perch (Macquaria ambigua).

Genomic vulnerability is a measure of how much evolutionary change is required for a population to maintain optimal genotype-environment associations under projected climates. Aquatic species, and in particular migratory ectotherms, are largely underrepresented in studies of genomic vulnerability. Such species might be well equipped for tracking suitable habitat and spreading diversity that could promote adaptation to future climates. We characterised range-wide genomic diversity and genomic vulnerability in the migratory and fisheries-important golden perch (Macquaria ambigua) from Australia's expansive Murray-Darling Basin (MDB). The MDB has a steep hydroclimatic gradient and is one of the world's most variable regions in terms of climate and streamflow. Golden perch are threatened by fragmentation and obstruction of waterways, alteration of flow regimes, and a progressively hotter and drying climate. We gathered a genomic dataset of 1049 individuals from 186 MDB localities. Despite high range-wide gene flow, golden perch in the warmer, northern catchments had higher predicted vulnerability than those in the cooler, southern catchments. A new cross-validation approach showed that these predictions were insensitive to the exclusion of individual catchments. The results raise concern for populations at warm range edges, which may already be close to their thermal limits. However, a population with functional variants beneficial for climate adaptation found in the most arid and hydrologically variable catchment was predicted to be less vulnerable. Native fish management plans, such as captive breeding and stocking, should consider spatial variation in genomic vulnerability to improve conservation outcomes under climate change, even for dispersive species with high connectivity.

Adapting generalized suitability curves from Brown trout to Minnow using 1D and 2D aquatic habitat models

The article focuses on adapting generalized depth preference and flow velocity characteristics from Brown trout (Salmo trutta morpha fario) to the Minnow (Phoxinus phoxinus). The results obtained were used to model habitat suitability with 1D and 2D models. Since 1995, research on assessing aquatic habitat quality has been ongoing on 77 mountain streams in Slovakia. This assessment employs a System of Environmental Flow Analysis (SEFA), which is based on the Instream Flow Incremental Methodology (IFIM). In most sections, Brown trout occurred in representative numbers. Brown trout habitat preferences were derived and generalized, and represented by suitability curves. Minnows were present in sufficient numbers for the derivation of suitability curves only on some streams, making direct generalization from the measured data unrepresentative. The measurement results showed that Minnow has similar depth and flow rate preferences to Brown trout. Therefore, it can be assumed that it is possible to adapt the generalised suitability curves from Brown trout to Minnow. This expansion enabled us to broaden the assessment of habitat quality using the SEFA model to mountain streams that are dominated by Minnows and where there is insufficient Brown trout presence. Verification of parameter adaptation from Brown trout to Minnow was conducted in 11 sections of mountain streams. We discuss the performance of habitat quality modeling, concerning the fundamental hydraulic characteristics of streams, using both 1D and 2D models. The results of the 2D modeling are presented for a sub-mountain stream.

Distinct Ecological Habits and Habitat Responses to Future Climate Change in Two Subspecies of Magnolia sieboldii K. Koch, a Tree Endemic to East Asia

Magnolia sieboldii, an important ornamental tree native to East Asia, comprises two subspecies in distinct regions, with wild populations facing suboptimal survival. This study aimed to understand the potential habitat distribution of these subspecies under future climate-change conditions to support climate-adaptive conservation. The maximum entropy (MaxEnt) model was used with occurrence and environmental data to simulate the current and future suitable habitats under various climate scenarios. Precipitation in the warmest quarter played a crucial role in shaping the potential habitats of both subspecies; however, they exhibited different sensitivities to temperature-related variables and altitude. Magnolia sieboldii subsp. sieboldii is more sensitive to temperature seasonality and annual mean temperature, whereas Magnolia sieboldii subsp. japonica is more affected by altitude, mean temperature in the driest quarter, and isothermality. Currently, the subsp. sieboldii is predicted to have larger, more contiguous suitable habitats across northeastern China, the Korean Peninsula, and Japan, whereas the subsp. japonica occupies smaller, more disjunct habitats scattered in central and western Japan and the southern Chinese mountains. These two subspecies will respond differently to future climate change. Potentially suitable habitats for subsp. sieboldii are expected to expand significantly northward over time, especially under the SSP585 scenario compared with the SSP126 scenario. In contrast, moderately and highly suitable habitats for the subsp. japonica are projected to contract southward significantly. Therefore, we recommend prioritizing the conservation of the subsp. japonica over that of the subsp. sieboldii. Strategies include in situ and ex situ protection, introduction and cultivation, regional hybridization, and international cooperation. Our study offers valuable insights for the development of targeted conservation strategies for both subspecies of M. sieboldii to counteract the effects of climate change.

Analyzing the Distribution Patterns of Endemic Quercus vulcanica (Boiss. et Heldr. ex) Kotschy in Türkiye Under Climate Change Using Ensemble Modeling

Quercus vulcanica (Boiss. et Heldr. ex) Kotschy (Kasnak oak), one of the 18 Quercus species naturally distributed in Anatolia, is an endemic species with a restricted distribution range. In accordance with the International Union for the Conservation of Nature (IUCN) Red List of Endangered Species classification, Quercus vulcanica is designated as a species of low risk (LC: Least Concern). However, it is predicted that the habitat of Quercus vulcanica will narrow and that the species will become endangered as a result of potential climate change scenarios in the future. The aim of this study was to estimate the temporal and spatial distribution of Quercus vulcanica in Anatolia during the LGM, as well as to examine the impact of present and future climate changes on the species. In this context, principal component analysis was applied to 19 bioclimatic variables of the Community Climate System Model Version 4 (CCSM4) climate model, with nine variables identified for use in modeling. Habitat suitability was estimated using the Biodiversity Modeling (BIOMOD) ensemble modeling method, which combines the results of nine different algorithms through the R package ‘biomod2’, applying both committee averaging and weighted average approaches. To evaluate the performance of the models, the Area Under the Curve (AUC) of Receiver Operating Characteristics (ROC), True Skill Statistics (TSS), KAPPA and Boyce Index were calculated. The contributions of the environmental variables were determined on a per-algorithm-model basis. The results of the analyses show that the bioclimatic variables that contribute the most to the distribution of the species are Bio8. The modeling results show that Quercus vulcanica is capable of occupying suitable habitat areas across the majority of Anatolia during the Last Glacial Maximum (LGM). It is anticipated that future projections will indicate a notable reduction in the extent of suitable habitat for the species, with the remaining areas confined to the vicinity of the Ilgaz Mountains, Köroğlu Mountains and Bolkar Mountains. Given the increasing destruction that Quercus vulcanica, an endemic plant, will be adversely affected by as a result of human impacts and climate change, it is of the highest importance to develop adaptation strategies with a view to protecting the species’ habitat and the sustainability of the species.

Predicting the Potential Distribution of the Endangered Pyrethrum tatsienense in China Using an Optimized Maxent Model Under Climate Change Scenarios.

Climate change can significantly impact the ecological suitability and diversity of species. Pyrethrum tatsienense, a critically endangered species in China, requires a thorough understanding of its habitat distribution and the environmental factors that affect it in the context of climate change. The Maxent algorithm was used to examine the key factors influencing the distribution of P. tatsienense in China, using data from 127 species occurrences and environmental variables from the Last Interglacial (LIG), Last Glacial Maximum (LGM), Mid-Holocene (MH), current, and future scenarios. The Maxent model was optimized utilizing the R package ENMeval, providing the most accurate predictions for suitable habitats across various scenarios. Results show that suitable regions for P. tatsienense encompass approximately 15.02% (14.42 × 105 km2) of China, predominantly on the Qinghai-Tibetan Plateau. The mean UV-B of the highest month (UVB3: 39.7%), elevation (elev: 28.7%), and the warmest season of precipitation (Bio18: 17.4%) are the major limiting factors for suitable habitat. The optimal species distribution ranges are identified as > 7500 J m-2 day-1 for UVB3, 2700-5600 m for elev, and 150-480 mm for Bio18. Predictions for the historical climate indicate the presence of refugia at the junction of Sichuan, Tibet, and Qinghai. The MH predictions show an increase in climatic suitability for P. tatsienense compared to the LIG and LGM, with an expansion of suitable areas westward. Future climate change scenarios indicate that the potential suitable habitat for P. tatsienense is expected to increase with increasing radiative forcing, with higher latitude regions becoming new marginally suitable habitats. However, predicted environmental changes in western Tibet may drive the loss of highly suitable habitats in the future. These findings enhance our understanding of how environmental factors impact the habitat suitability of P. tatsienense and provide valuable insights for developing effective management and conservation strategies for this important species.

Influence of Spawning and Nursery Ground Environmental Changes on Walleye Pollock Catches Along the Eastern Coasts of Korea and Japan After the Late-1980s Climate Regime Shift

The eastern coasts of Korea (ECK) and Japan (ECJ) are located at the southernmost limit of walleye pollock distribution in the Northwest Pacific. Following the climate regime shift (CRS) in the late 1980s, pollock catches in these regions have declined sharply, with different trends emerging. This study examined the relationship between environmental factors, such as sea surface temperature (SST) and habitat suitability, and changes in pollock catches from the late 1980s to 2022. From the late 1980s to the late 1990s, El Niño and positive Pacific decadal oscillation (PDO) phases dominated, increasing SST in the ECK and ECJ habitats and rapidly decreasing catches. Although spawning grounds (SGs) have maintained high habitat suitability, nursery ground (NG) suitability has declined. From the late 1990s to 2022, La Niña and negative PDO phases prevailed, with SST continuing to rise along the ECK, further reducing catches. SG suitability remained high, but NG suitability declined. Along the ECJ, SST decreased after the late-1990s CRS, stabilizing catches. After the mid-2010s, the SST increased along the ECJ, reducing pollock catches, although SG suitability remained high. This study elucidates SST changes during early life stages and their effects on pollock catch, habitat, and resources in future marine environments.

Predicting the Impact of Climate Change on Corylus Species Distribution in China: Integrating Climatic, Topographic, and Anthropogenic Factors.

This study investigates the impact of climate change on the distribution of Corylus species in China using the MaxEnt model. Key environmental variables, such as Bio6 (mean temperature of the coldest month) and human footprint, emerged as significant determinants of habitat suitability. The study reveals substantial shifts in suitable habitats due to global warming and increased precipitation, with notable expansion towards higher latitudes. Species like Corylus heterophylla Fisch. ex Bess. and Corylus mandshurica Maxim. demonstrate resilience in extreme conditions, highlighting the importance of specific ecological traits for conservation. Future projections under various SSP scenarios predict continued habitat expansion, emphasizing the need for targeted conservation strategies to address the critical role of human activities. This research highlights the complex interplay between climatic, topographic, and anthropogenic factors in shaping Corylus habitats, advocating for integrated adaptive management approaches to ensure their sustainability amid ongoing climate change.

Predicting the Global Potential Suitable Areas of Sweet Osmanthus (Osmanthus fragrans) Under Current and Future Climate Scenarios.

Osmanthus fragrans is a valuable landscaping tree that is appreciated worldwide. However, the optimal environmental conditions for O. fragrans cultivation have yet to be studied in detail, which hinders the preservation of wild resources of this plant and its commercial exploitation. The maximum entropy model was applied to assess the significance of environment variables influencing O. fragrans distribution. Combining data from 629 global distribution points for O. fragrans, predictions were made on the potential effects of climate change on the geographical distribution of suitable habitats for this species in the present and the future. The results indicated that O. fragrans preferred a warm and humid growing environment. Under the current climatic conditions, the potential habitats for O. fragrans were mostly located in the eastern coastal areas of the continents at medium and low latitudes. The main environmental variables that affected its distribution were the precipitation during the warmest quarter, the temperature seasonality, and the mean temperature of the warmest quarter. The analysis indicated that the continuation of current trends in climate change will result in the further reduction of suitable habitats for O. fragrans growth, and the global centroid will shift to the southeast. These findings provided insight into the impact of climate change on O. fragrans habitats, as well as provide guidance for the conservation of wild resources of this species and the breeding of more climate change-resistant varieties for the future.

Long live the cat: Ocelot population viability in a planned reintroduced population in Texas, USA

AbstractReintroductions are often needed to recover carnivore populations and restore ecological processes. Felids are common subjects of reintroduction efforts, but published population models informing felid reintroduction plans are uncommon, and poor planning has sometimes caused issues in felid reintroduction programs. In the United States, ocelots (Leopardus pardalis pardalis) are classified as endangered, and recovery requires population expansion into historic habitat. A multi‐organization effort is underway to establish a new ocelot population in Texas by releasing ocelots into an area of 478 km2 of suitable habitat in ocelots' historic but now unoccupied range. In this study, we used population viability analyses to compare different ocelot reintroduction strategies for the identified reintroduction area. Based on a potential ocelot breeding program's limitations, we modeled reintroduction using a founding population of no more than six ocelots and no more than four ocelots released per year for no more than 15 subsequent years. Within these limitations, we assessed projected population abundances and extinction risks after 30 years for 20 different reintroduction strategies. We found that long‐term releases are necessary to establish a viable population; under conservative model assumptions, releasing six ocelots in the initial year and then releasing four individuals annually for an additional 10–15 years is necessary for attaining a projected population greater than 36.62 ocelots (baseline) with <6% extinction risk. We also found that ocelot population abundance is about equally sensitive to post‐release mortality and inbreeding depression. This highlights the importance of not only supporting reintroduced ocelots' survival but also managing for high genetic diversity in the reintroduction program. Further, we found that realistic but more liberal assumptions on the carrying capacity of the reintroduction area and the age of first reproduction for ocelots increase projected population abundances (53.95 individuals and 61.26 individuals, respectively), and thus reintroduction success. The model's sensitivity to carrying capacity suggests that long‐term habitat protection and expansion are among the most important management actions to support ocelot reintroduction. Our study establishes the first population viability model for an ocelot reintroduction plan anywhere across the species' wide geographic range, and it reinforces several key considerations for wildlife reintroduction efforts worldwide.

A GIS-coupled thermal response model for predicting the population growth potential of the red cotton bug, Dysdercus koenigii (Fabricius) (Hemiptera: Pyrrhocoridae) in India under climate change conditions

Recently, the red cotton bug has become a significant menace to cotton in India. With the potential for increased habitat suitability due to predicted temperature rise of 2.5°C under future climate change in India, this pest could become even more severe in certain regions. Addressing the knowledge gap on the temperature-driven population growth of this pest is crucial for developing a climate-resilient pest management strategy. In this study, life history data gathered at various constant temperatures (15°C to 35°C) were used to estimate temperature thresholds and thermal requirements for the red cotton bug development. Stochastic estimation of life table parameters and validation with real-time weather data were performed. The phenology model, integrated into a geographic information system, projected the future pest status based on SSP126 temperature change scenarios for the year 2050. The temperatures between 8.35 – 10.83 °C were estimated as lower developmental thresholds for various immature life stages. The optimum and upper threshold temperatures estimated for different life stages ranged between 22.14 – 28.32°C and 35.80 – 39.08°C, respectively. Thermal requirements of 447.97 degree days for life cycle completion were estimated. The optimum immature survival rates (>70%) were observed at temperatures between 25-30°C. The temperature-dependent decrease in generation times from 90.45 days (15 °C) to 25.44 days (35°C) was observed, whereas maximum fecundity was recorded at 32°C. Simulation at fluctuating temperatures across different cotton growing locations provided reasonably similar results on potential population increase (finite rate of increase: 0.99 - 1.04 females/female/day and a generation time of 44.25 – 83.97 days). Risk mapping highlighted moderate to high suitability (ERI >0.4, GI > 6, and AI >4) of various cotton growing areas under current climate, and projected shifts in suitability under future climate change. The study has generated information valuable for implementing effective and timely pest management strategies for RCB. Integrating the field observations with model outputs can enhance a practical understanding of red cotton bug dynamics.

An Updated Framework for Modeling White-Tailed Deer (Odocoileus virginianus) Habitat Quality in Illinois, USA.

White-tailed deer (Odocoileus virginianus) are a cervid species found mostly in the Americas. Managing white-tailed deer requires understanding their relationship with the environment, which was characterized by Roseberry and Woolf (Wildlife Society Bulletin 1, 1998, 252) for all counties in Illinois, USA, who incorporated habitat quantity and quality in a deer habitat suitability index. However, this index was based on satellite imagery from 1996 and did not explore the smaller spatial scales used by deer. Our study addressed these gaps by developing a deer land cover utility (LCU) score for each TRS (township, range, and section), township, and county in Illinois based on the methodology outlined in Roseberry and Woolf (Wildlife Society Bulletin 1, 1998, 252) but using data from the National Land Cover Database (2001-2021). These deer LCU scores were validated against minimum deer population data using Bayesian regression with additional covariates relevant to hunting and deer density. These models performed well with Bayesian R 2 values of 0.501 (TRS), 0.5 (township), and 0.969 (county). The regression coefficients for the deer LCU scores were statistically significant (95% credibility interval not containing 0) and positive at the TRS, township, and county levels, reflecting the expected relationship between minimum deer density and deer LCU. Predictions made by these regression models on new data were accurate, with the median absolute difference between the true and predicted values being 0.398 deer/km2 for TRS', 0.085 deer/km2 for townships, and 0.066 deer/km2 for counties. This deer LCU could be used in other studies about deer in Illinois or studies in which deer are a relevant factor such as investigations about deer disease or tick distribution. This modeling approach could also be adapted to different wild species, locations, and/or time periods for which land cover data is available.

A habitat is not enough - increasing the chances of success for species reintroduction in riverscapes by habitat modeling and connectivity analysis

Alpine rivers are among the most heavily modified ecosystems in Europe. Following massive interventions in the 18th and 19th centuries, many plant species specialized in these challenging environments declined and are now endangered or even locally extinct. Today, attempts are being made to reintroduce these species as part of restoration measures, but only a few are successful. The selection of potential sites for reintroduction is commonly intuitive and based on practical considerations, while a prior scientific assessment of habitat availability and habitat connectivity is lacking. To increase the success of future reintroductions, we employ a habitat suitability model and subsequent habitat connectivity analysis to identify promising regions and patches for reintroduction within a riverscape. We demonstrate this approach using the Alpine river specialists Chondrilla chondrilloides and Myricaria germanica in three differently degraded and one restored section of the large Alpine river Isar. All river sections provide habitats for both species, but with increasing degradation, habitats become fewer and less connected. For the species with a narrower habitat niche and lower dispersal ability, suitable and connected patches that support a self-sustained metapopulation are only found in the near-natural sections. Despite an improvement in the habitat situation, the patch size in the restored section is too small, and the patches are too scattered to support a successful reintroduction of the species. We show that this evidence-based approach outperforms an intuitive selection of out-planting sites. The results further underline the importance of using scientific habitat analysis to increase the success of reintroduction measures.