Optimal Habitat Research Articles

THE FIRST REPORTED PLEISTOCENE BEAVER, <i>Castor fiber</i> (CASTORIDAE, RODENTIA), FROM THE GOBI ALTAI REGION OF MONGOLIA

Here, we report a fragmentary Castor fiber (Linnaeus, 1758) proximal ulna from Tsagaan Agui Cave (Gobi Altai Mountains, southern Mongolia). This constitutes the first fossil evidence of this species from Mongolia. C. fiber is currently regarded as extinct in the Gobi Desert but fossilized remains recovered from cave deposits provide evidence that optimal habitat conditions for C. fiber existed in the Gobi Desert during some periods of the Pleistocene. Pleistocene C. fiber remains are relatively rare in neighboring regions, including Siberia and the Russian Far East. Here, we review the geographical distribution of fossil C. fiber in Central Asia, southern and eastern Siberia, and the Russian Far East.

Upwellings, canyons and whales: An important winter habitat for balaenopterid whales off Mauritania, northwest Africa

The aim of this study was to identify critical habitats for baleen whales in the Mauritanian upwelling zone using data collected from a platform of opportunity: a 60 day geophysical survey approximately 100km southwest of Cap Blanc, Mauritania in winter (2012/13). The bathymetry of the 5,500km2 study area was complex, including parts of the Cap Timiris Canyon system. Large whales, including sei and blue whales, accounted for 70% of the 238 cetacean sightings. Species identification was often problematic, especially in the case of balaenopterid whales, so data for all whales of this genus were pooled for the estimation of abundance and distribution. Spatial modelling was applied to estimate abundance and to plot a predicted density map of balaenopterid whales. Depth and the chlorophyll-a concentration when at its peak (in the previous September) were significant predictors of whale density. Point abundance in the study area was estimated at 272 whales (95% CI 265–279) and density was highest in the depth range 500–2,250m near to the canyon system (6.18 whales/100km2 , 95% CI 6.03–6.51). Steep seabed topography created by canyons running off the shelf edge, together with the strong upwelling system, probably create optimal habitats for the euphausiid prey of sei and blue whales. Sei whales were observed skim-feeding at dawn or dusk on seven occasions; in one sighting an aggregation of 18 skim-feeding sei whales were observed. The high density of these baleen whale species in such a highly productive area and direct observation of feeding behaviour in sei whales, provides evidence of feeding during the winter breeding season, when they have previously been presumed to feed less. This study demonstrates the potential value of collecting further data on seismic survey vessels and would improve understanding of cetacean ecology in remote and under-explored regions.

Identifying optimal values of coastal habitat condition for management and restoration

Fish assemblages are considered valuable monitoring targets for coastal and marine ecosystems because their populations can reflect ecosystem condition. Human impacts to coastal seascapes are pervasive, necessitating management and restoration actions that are assessed against quantitative targets. Relationships between metrics of habitat condition and animal assemblages can be used to identify where management interventions should aim to maximise outcomes for key functions and services. In this study, we surveyed fish assemblages (using underwater videography) and habitat condition (focusing on the size, composition and complexity of habitats) of five estuarine ecosystems (mangrove forests, seagrass meadows, saltmarsh, log snags and rocky outcrops) across 13 estuaries over two years (for n = 981 sites) in southeast Queensland, Australia. We used generalised additive models to quantify relationships and identify thresholds between metrics indexing habitat condition and key metrics of fish assemblages (species richness and abundance), and used these models to calculate optimal habitat condition values that maximise habitat value for fish and fisheries. We also identified indicator fish species whose abundance correlated with these optimal values. Metrics of habitat condition that index food availability for fish (such as algae and oyster cover) or broader habitat complexity (such as seagrass height or mangrove canopy cover) were consistently important for fish biodiversity and abundance. Relationships were readily translated into optimal values for key metrics of habitat condition for four of the five ecosystems surveyed. We propose that incorporating optimal values of habitat condition into management would maximise the abundance of key indicator fish species, including several which are important fisheries targets. The findings of this study will help managers to identify the optimal condition requirements of coastal ecosystems, thereby maximising the effectiveness and efficiency of often sparse management resources.

Habitat suitability evaluation and ecological corridor construction of wintering cranes in Poyang Lake

The construction of ecological corridor is of great significance in alleviating the impact of habitat fragmentation on habitat quality and maintaining the stability of regional ecosystem. Taking overwintering cranes in a typical wetland of Poyang Lake as the research object, the ecological source was screened by calculating landscape connectivity, and the resistance factor and minimum cumulative resistance model were determined by analytic hierarchy process (AHP) to construct an ecological corridor, and the habitat connectivity scheme of overwintering cranes in a typical wetland of Poyang Lake was discussed. The results showed that: ① The resistance surface was relatively high in the central, northern, eastern, central, western and southwestern regions of the study area, but relatively low in the eastern, northwestern and southeastern regions of the study area. ② From 2010 to 2020, the optimal habitat changed from 104.51 km2 to 79.03 km2, and concentrated in the eastern and southern regions of the study area. The least suitable habitat changed from 59.53 km2 to 104.78 km2, and concentrated in the middle line of the study area. ③ In this study, 18 potential ecological corridors were constructed, which were mainly distributed in Fenglin Mountain, Dengjia Village and Banshan Village in the south of the study area and Wangjiadun, Desert Zhou, Houshanzhou and Laoxu Village in the east.

Pest Risk Assessment of Aeolesthes sarta (Coleoptera: Cerambycidae) in Pakistan under Climate Change Scenario

Aeolesthes sarta (Solsky 1871) (Coleoptera: Cerambycidae) is a polyphagous longhorned beetle species that primarily damages broadleaved tree species. This pest is distributed in the western and northern regions of Pakistan, where it caused serious damage to Populus spp. plantations. However, the growth and dispersal patterns of insects and pests are changing due to climate change. Modeling the range expansion or contraction of A. sarta development regions in Pakistan was the goal of the current study, assuming climate change might influence the geographical distribution of A. sarta in Pakistan. Under historical and future climatic conditions, A. sarta distribution areas were estimated using the CLIMEX model. Three time periods, 2030 (early century), 2070 (late century), and 2100 (end century), were forecasted for habitat suitability using the two climate change scenarios (CCSs) A1B and A2. Under the historic climatic condition (HCC), A. sarta was distributed in most areas of Pakistan, and its optimum habitat accounted for 71.67% of its total potential distribution. In the early-century period, optimum habitat dropped to 50.60% and 52.22% under A1B and A2 scenarios in the suitable condition. In the late-century period, optimum habitat further reduced to 31.76% and 30.60% under A1B and A2 scenarios. Moreover, at the end-century period, severe range shrinkage was predicted in the optimum habitat (19.99% under both CSSs). The model predicted a shift in the suitable habitat areas for A. sarta to the west and north. Furthermore, most climatically suitable areas under historic conditions became unsuitable during the end-century period. These projected results will assist in identifying the impacts of global warming on the possible distribution of A. sarta, thereby offering vital information for developing early forecasting and pest-prevention techniques to prevent further loss of forest and woodland trees.

Current status of gastric and oral infection/diseases caused by Helicobacter pylori

AbstractHelicobacter pylori is found in the stomach, which is its optimal habitat, and is considered an important factor in various serious diseases, including stomach cancer. The World Health Organization has identified H. pylori as a causative agent of gastric cancer, as confirmed by animal experiments in rodents. The fact that H. pylori can live in the harsh environment of stomach acid was the greatest hindrance to the discovery of H. pylori. It was not so long ago, in 1983, that it was successfully isolated and cultured. Subsequently, H. pylori eradication therapy was established, and it became possible to control gastric cancer to some extent. However, the mechanism, route, and mode of H. pylori infection still remain unclear. Furthermore, currently, the prevention of first‐episode gastric cancer and control of recurrent gastric cancer are not perfect. One of the reasons for this may be that the status of H. pylori in the oral cavity, which is the entry point for the organism (the beginning of the digestive system: the first route of infection), is still unknown. Therefore, we reviewed the current status of H. pylori infection in the stomach and oral cavity, focusing on (1) the mechanism of infection, (2) pathogenic factors, (3) the actual status of eradication therapy, and (4) control strategies.

First record of the Delicate Salt Flat Mouse, Salinomys delicatus Braun & Mares, 1995 (Rodentia, Cricetidae) in a xeric environment of northwestern Córdoba (Argentina), with comments on its conservation status

Salinomys delicatus Braun & Mares, 1995 is a sigmodontine rodent endemic to perisaline environments in west-central Argentina. It is currently considered to be a Vulnerable species due to its patchy distribution and the loss of optimal habitats caused by intensive anthropogenic activities. In this work, we document the first record for this species in the Dry Chaco ecoregion of northwestern Córdoba province (Argentina), enlarging the geographic distribution of this species by approximately 115 km to the east of previously known occurrences. Our new record highlights the need to strengthen conservation policies in the Dry Chaco of Córdoba province.

Geographical distribution and predict potential distribution of Cerasus serrulata.

Climate change is closely related to the distribution of plant resources. Cerasus serrulata is an important plant resource in China. The study on the influence of environmental factors on the distribution of suitable areas of C. serrulata is conducive to the protection and development of C. serrulata. In this paper, the distribution information of 238 Chinese Cerasus serrulataplants was processed by DIVA-GIS. The MaxEnt model was used to simulate the current and future distribution, and the ecological distribution and richness of Cerasus were analyzed. The results showed that the Cerasus serrulata was widely distributed in Hebei, Heilongjiang, Shandong, Jiangsu, Zhejiang, Anhui, Jiangxi, Hunan, and Guizhou provinces, mainly in the low and middle elevation areas of 10 to 1200m. Based on this model, the precipitation of the warmest quarter, the precipitation of the driest month, and the mean temperature of the coldest were the most significant bioclimatic variables affecting the distribution of C. serrulata. In the future, climate change may lead to a slight increase of 2.31% in the area of suitable habitat for Cerasus serrulata, while the optimal habitat will decrease from 20.81 to 14.55%. Therefore, conservation measures should be taken to protect these precious resources.

Microhabitat modeling of the invasive Asian longhorned tick (Haemaphysalis longicornis) in New Jersey, USA

The Asian longhorned tick (Haemaphysalis longicornis) is a vector of multiple arboviral and bacterial pathogens in its native East Asia and expanded distribution in Australasia. This species has both bisexual and parthenogenetic populations that can reach high population densities under favorable conditions. Established populations of parthenogenetic H. longicornis were detected in the eastern United States in 2017 and the possible range of this species at the continental level (North America) based on climatic conditions has been modeled. However, little is known about factors influencing the distribution of H. longicornis at geographic scales relevant to local surveillance and control. To examine the importance of local physiogeographic conditions such as geology, soil characteristics, and land cover on the distribution of H. longicornis we employed ecological niche modeling using three machine learning algorithms - Maxent, Random Forest (RF), and Generalized Boosting Method (GBM) to estimate probability of finding H. longicornis in a particular location in New Jersey (USA), based on environmental predictors. The presence of H. longicornis in New Jersey was positively associated with Piedmont physiogeographic province and two soil types - Alfisols and Inceptisols. Soil hydraulic conductivity was the most important predictor explaining H. longicornis habitat suitability, with more permeable sandy soils with higher hydraulic conductivity being less suitable than clay or loam soils. The models were projected over the state of New Jersey creating a probabilistic map of H. longicornis habitat suitability at a high spatial resolution of 90×90 meters. The model's sensitivity was 87% for locations sampled in 2017-2019 adding to the growing evidence of the importance of soil characteristics to the survival of ticks. For the 2020-2022 dataset the model fit was 57%, suggestive of spillover to less optimal habitats or, alternatively, heterogeneity in soil characteristics at the edges of broad physiographic zones. Further modeling should incorporate abundance and life-stage information as well as detailed characterization of the soil at collection sites. Once critical parameters that drive the survival and abundance of H. longicornis are identified they can be used to guide surveillance and control strategies for this invasive species.

Феногеногеография популяций сосны обыкновенной Якутии и Приамурья

Abstract. To preserve biological diversity, it is necessary to determine the genetic structure of species populations, because this gives the most complete picture of the manifestation of polymorphism and makes it possible to detect genetically and phenotypically distinct subspecies. The information obtained will help determine the optimal habitat and protection conditions for endangered and farmed species. The purpose of research is to conduct an allozyme analysis of 10 populations of P. sylvestris L. 2 of the physiographic countries of Yakutia and the Amur region. Results. An allozyme analysis revealed less polymorphism and the most drastic differentiation of the Amur region populations (at the level of geographic race) from Yakutia populations, subdivided from each other at the level of geographical populations. Significant differences are shown between the populations of Yakutia and Amur Region according to the distances of Mahalanobis, calculated according to 19 signs of cones. A positive linear relationship was obtained between the distances of Mahalanobis (D2) and the genetic distances of Ney (DN78) (R2 = 0.4159). Scientific novelty. A dominant role in the origin of the Yakut populations of P. sylvestris of three Siberian group-gradual fellings (GGF) - Tynda, Romanovka, Irkutsk and a decrease in the genetic similarity of the GGF as they move away from Yakutia were found.

Multidecadal trends in ultraviolet radiation, temperature, and dissolved oxygen have altered vertical habitat availability for Daphnia in temperate Lake Giles, USA

Abstract Long‐term browning has resulted in increases in dissolved organic carbon and reduced water clarity that have altered the vertical physical structure of many lake ecosystems. The primary responses include reduced ultraviolet (UV) penetration, warming surface waters, and decreased deepwater dissolved oxygen concentrations that interactively alter vertical habitat suitability for zooplankton. Over 3 decades, Daphnia populations have decreased in abundance and shallowed in their vertical distribution in temperate Lake Giles (Pennsylvania, USA). Using 3 decades of corresponding long‐term vertical profile data of UV radiation, water temperature, and dissolved oxygen, we modelled both the suitable vertical habitat and thermally optimal habitat for Daphnia to understand the potential role of habitat availability for their population dynamics. The vertical extent of suitable habitat increased over time primarily due to strong decreases in UV penetration. In contrast, thermally optimal habitat decreased due to strong increases in vertical thermal gradients that were especially strong in late summer. The vertical distribution of Daphnia became shallower over this time period and may be a response to lower UV exposure near the surface, but continued warming of surface waters and decreasing deepwater dissolved oxygen concentrations are likely to lead to a vertical habitat squeeze. The biological implications of long‐term browning require more attention due to the complex and important implications for population dynamics, species interactions, and food web structure in lakes.

Nest orientation and proximity to snow patches are important for nest site selection of a cavity breeder at high elevation

Timing and location of reproduction are central to reproductive success across taxa. Among birds, many species have evolved specific strategies to cope with environmental variability including shifts in timing of reproduction to track resource availability or selecting suitable nest location. In mountain ecosystems, complex topography and pronounced seasonality result in particularly high spatiotemporal variability of environmental conditions. Moreover, the risk of climate‐induced resource mismatches is particularly acute in mountain regions given that temperature is increasing more rapidly than in the lowlands. We investigated how a high‐elevation passerine, the white‐winged snowfinch Montifringilla nivalis, selects its nest site in relation to nest cavity characteristics, habitat composition and snow condition. We used a combination of field habitat mapping and satellite remote sensing to compare occupied nest sites with randomly selected pseudo‐absence sites. In the first half of the breeding season, snowfinches preferred nest cavities oriented towards the morning sun while they used cavities proportional to their availability later on. This preference might relate to the nest microclimate offering eco‐physiological advantages, namely thermoregulatory benefits for incubating adults and nestlings under the harsh conditions typically encountered in the alpine environment. Nest sites were consistently located in areas with greater‐than‐average snow cover at hatching date, likely mirroring the foraging preferences for tipulid larvae developing in meltwater along snowfields. Due to the particularly rapid climate shifts typical of mountain ecosystems, spatiotemporal mismatches between foraging grounds and nest sites are expected in the future. This may negatively influence demographic trajectories of the white‐winged snowfinch. The installation of well‐designed nest boxes in optimal habitat configurations could to some extent help mitigate this risk.

Fuzzy logic modelling of anadromous Arctic char spawning habitat from Nunavik Inuit knowledge

Anadromous Arctic char (Salvelinus alpinus, Iqaluppik) and their freshwater habitats are vulnerable to the effects of climate change. Spawning habitats are critical to ensure the propagation of populations and the fisheries they support. However, detailed descriptions for river systems in the Canadian Arctic are limited, especially in the Nunavik region. As Arctic char is a traditionally important species for culture and subsistence of Inuit, some harvesters have a deep knowledge pertaining to habitat use, including optimal habitat conditions for spawning. Interviews of Inuit knowledge holders on Arctic char, were conducted in three communities of Nunavik, Canada: Kangiqsualujjuaq, Tasiujaq and Kangirsuk. From the knowledge of Inuit experts, the most suitable spawning habitats were located in rivers, at depths between 0.6 m and 1.5 m with velocities > 0.1 m/s. A large range of riverbed substrate was deemed suitable as long as the smaller substrate size class showed some presence of gravel or coarse sand, depending on the local geomorphology. We used fuzzy logic to code natural language description provided by Inuit experts into a numerical value representing the Habitat Suitability Index for spawning sites. The model was able to predict the spawning habitat suitability or unsuitability of 14 out of 15 sites, given values of depth, velocity, and substrate. The methodology presented is well-suited to build quantitative model based on the description of local observations and could be applied for other animal or plant species for which local and/or traditional knowledge exists.

BREEDING SITES CHARACTERISTICS AND MOSQUITO ABUNDANCE IN SOME SELECTED LOCATIONS WITHIN KADUNA METROPOLIS

Natural or artificial collection of water serves as an optimum habitat that supports mosquito’s breeding, while savannah, grasslands or shady low woodlands supports their resting activities, swarming and mating. Samples were collected from breeding sites within some selected locations from January to June. Five hundred and thirty two mosquito larvae belonging to 3 genera Culex, Anopheles and Aedes were collected and seven species of mosquitoes were identified comprising; Culex quinquefasciatus 102 (19.17%), Aedes aegypti 345(64.84%), Culex decens 8 (1.50%), Aedes vittatus 49 (9.21%) Culex simpsoni 8(1.50%), Culex tigripes 17 (3.20%) and Anopheles gambiae 3(0.50%). Aedes aegypti was common in all the locations. Water samples were collected from seven different major breeding sites such as abandoned tyres 155(50.82%), Concrete gutters 50(16.39%), Pools 10 (3.27%) ponds 4 (1.31%), Plastic containers50 (16.39%), Potholes 6 (1.97%) and Metallic containers30 (9.84%) totaling 305 sampled breeding sites. The characteristics of breeding sites noted were the movement of water in the breeding places, the consistency of the presence of water in the breeding places, the existence of vegetation on the breeding and types of predators. Correlation analysis showed abundance of mosquitoes decreased with increase in physicochemical parameters. In conclusion, the common house mosquito (Aedes aegypti) was most abundant and occurring in abandoned tyres; while the physico-chemical parameters were all within the acceptable limits for mosquito breeding.

Evaluation of Habitat Suitability Index Model of Indian Gharial in National Chambal Sanctuary, M.P. India

Almost all animals use their habitats in a non-random manner. But the cost and benefits of using specific habitat types remain unknown for many types of organisms. Habitat suitability models aim to assess the relationship between species and their habitat and accurately predict the species response to habitat changes. We developed a riverine habitat model for Gharial (Gavialis gangeticus), a critically endangered species, in the National Chambal Sanctuary in India after reviewing and synthesizing existing information. Based on the model, an index of habitat suitability is produced, ranging from 0 (unsuitable habitat) to 1 (optimal habitat). The results of the present study indicate that the Gharial prefer deep pools in water bodies. The deep waters serve as feeding and breeding grounds for Gharial. They prefer water with a velocity ranging from 20–70 cm.sec-1 . Sandy banks are preferred as basking sites, mainly because they provide moisture during the warm months and because it seems that they find it easier to crawl on sandy surfaces than on rocky or clay surfaces. Insects, tadpoles, tiny fish, and frogs are preferred by young Gharial. A habitat suitability model for Gharial can be used as a decision support system in order to improve conservation efforts at different landscape scales.

Estimation of Albacore Tuna Potential Fishing Grounds in the Southeastern Indian Ocean

To maintain sustainable fisheries, albacore tuna is one of the commercial fish species whose management is regulated globally by the Regional Fisheries Management Organizations. Generally, sea surface temperature (SST) and chlorophyll-a (SSC) are used to determine fish suitability based on the catch data. In this research, we attempt to identify optimal habitats for albacore tuna in the southeastern Indian Ocean by analyzing in situ data based on onboard observers on tuna long line vessels from 2006–2019 and optimum interpolation sea surface temperature from NOAA-Advanced Very High-Resolution Radiometer and sea surface chlorophyll-a from Aqua MODIS satellites. The albacore tuna’s habitat suitability index was examined using the generalized additive model. The results suggested that albacore tuna inhabited waters with an SST range of 15–26 °C and SSC concentration of 0.075–0.125 mg/m3. In the Indian Ocean, most albacore tunas were captured at higher latitudes of 20°-30° S.

The effects of climate and land use change on the potential distribution and nesting habitat of the Lesser Adjutant in Nepal

Climate change and land use change pose a threat to the world's biodiversity and have significant impacts on the geographic distribution and composition of many bird species, but little is known about how they affect threatened large-sized waterbird species that rely on agricultural landscapes. To address this gap, we investigated how climate and land use changes influence the distribution and nesting habitats of the globally vulnerable Lesser Adjutant (Leptoptilos javanicus) in Nepal. Between 2012 and 2023, we collected distribution data from 24 districts and nesting site information from 18 districts. In a nation-wide breeding survey conducted in 2020, we documented a total of 581 fledglings from 346 nests in 109 colonies. The ensemble model predicted a current potential distribution of 15% (21,637 ​km2) and a potential nesting habitat of 13% (19,651 ​km2) for the species in Nepal. The highest predicted current suitable distribution and nesting habitat was in Madhesh Province, while none was predicted in Karnali Province. The majority of this predicted distributional and nesting habitat falls on agricultural landscapes (>70%). Our model showed a likely range expansion of up to 15% (21,573 ​km2) for the distribution and up to 12% (17,482 ​km2) for the nesting habitat under SSP5–8.5 scenarios for the 2070s. The range expansion is expected to occur mainly within the current distribution and breeding range (Tarai and some regions of Siwalk), particularly in Lumbini and Sudurpashchim provinces, and extend to the northern portions (Siwalik and Mid-hill regions) in other provinces. However, the current Protected Areas and Important Bird and Biodiversity Areas are inadequate for providing optimal habitats for the species. Although the model suggests range expansion, the use of such novel habitats is primarily contingent on the availability and protection of large-sized trees (particularly Bombax ceiba, observed in 65% of colonies) in agricultural regions where nesting occurs. Therefore, our research suggests that agricultural landscapes should be prioritized in management plans for the conservation of the Lesser Adjutant in Nepal.

Abundance of the bearded fireworm Hermodice carunculata (Polychaeta: Amphinomidae) increases across a euphotic-mesophotic depth gradient in the remote St. Peter and St. Paul’s Archipelago

The bearded fireworm Hermodice carunculata is widely distributed across tropical and subtropical Atlantic and Mediterranean Oceans and was previously considered to be mostly associated with shallow reefs. We provide here data on the distribution, abundance and habitat use of H. carunculata across a euphotic-mesophotic gradient (0-90 m) in the Saint Peter and Saint Paul’s Archipelago (SPSPA, Mid Atlantic Ridge, Brazil). Samples were obtained using SCUBA and a Remote Operated Vehicle (ROV). A total of 189 individuals were observed and a sharp increase in abundance with depth was recorded, particularly from 50 m depth onwards. In the mesophotic zone (50-90 m) individuals were closely associated with branching black-corals (Tanacetipathes spp.) and predation over black-corals and the scleractinian Madracis decactis was commonly sighted. A Boosted Regression Tree model indicated black-coral abundance as the main driver of H. carunculata abundance, suggesting that preference for optimal habitats to hide/forage is more important than depth per se on the bathymetric distribution of the fireworm. The high abundances of H. carunculata in the mesophotic zone, and its predation on keystone benthic cnidarians, suggests that this species play important roles in the dynamics of deep reefs.

Environmental Factors Driving the Spatial Distribution Pattern of Venerable Trees in Sichuan Province, China.

Venerable trees are important natural resources and cultural heritage, offering historical, ecological, social and economic value. However, global warming and anthropogenic activities have threatened their welfare and survival. A comprehensive understanding of their current and future spatial patterns, vis-á-vis environmental conditions, can inform the co-management of sustainable resource use and conservation. We employed the existing spatial occurrence data and environmental variables (bioclimate and elevation) to simulate the optimal habitats for venerable trees in China's Sichuan Province. We evaluated the current and future climate scenarios of 2100 with double CO2 concentration. The BIOCLIM and QGIS spatial analyses assessed the primary factors of geographical distribution. The results identified 10,720 venerable trees from 123 species, 81 genera and 42 families. Cupressus funebris dominated, with the maximum importance value, followed by Ginkgo biloba, Ficus virens var. sublanceolata, and Phoebe zhennan. The elevation distribution of tree abundance and species richness demonstrated a unimodal pattern, skewing to the low-elevation end, with a concentration in the 600-1500 m low-medium altitude. The majority of trees and excellent habitats were found in eastern Sichuan with a less harsh terrain and climate. The bio3 (isothermality) and bio7 (temperature annual range) factors significantly influenced tree occurrence. Temperature imposed a greater effect on distribution than moisture under the current climate scenario. For the future climate-change scenario, the suitable habitats were predicted to maintain an overall stable pattern, with largely contiguous expansions of better habitats. However, climate warming would shrink the excellent habitats on the plains. The findings can inform strategies and guidelines for venerable-tree conservation in Sichuan. Furthermore, vulnerable areas could be identified. The future range expansion sites could be enlisted to cultivate new trees to replenish the venerable-tree pool. Habitat patches that remain sustainable could provide refugia with the potential for protected-area designation.

Thermal physiology integrated species distribution model predicts profound habitat fragmentation for estuarine fish with ocean warming

Species distribution models predict a poleward migration for marine ectotherms with ocean warming. However, a key limitation in current species distribution models (SDM) is that they do not account for population-specific heterogeneity in physiological responses to temperature change resulting from local adaptations and acclimatization. To address this gap, we developed a novel, Physiology Integrated BioClimate Model (PIBCM) that combines habitat-specific metabolic thermal physiological tolerance of a species into a bioclimate envelope model. Using a downscaling approach, we also established a fine-resolution coastal sea-surface temperature data set for 2050–2080, that showed a high degree of location-specific variability in future thermal regimes. Combining predicted temperature data with the PIBCM model, we estimated habitat distribution for a highly eurythermal intertidal minnow, the Atlantic killifish (Fundulus heteroclitus), a species that likely presents a best-case-scenario for coastal vertebrates. We show that the killifish northern boundary shifts southwards, while distinct habitat fragmentation occurs in the southern sub-population (due to migration of adjacent fish populations to the nearest metabolically optimal thermal habitat). When compared to current SDMs (e.g., AquaMaps), our results emphasize the need for thermal physiology integrated range shift models and indicate that habitat fragmentation for coastal fishes may reshape nursery habitats for many commercially and ecologically important species.