Habitat Attributes Research Articles

Recommendations to enhance breeding bird diversity in managed plantation forests determined using LiDAR.

Widespread afforestation is a crucial component of climate mitigation strategies worldwide. This presents a significant opportunity for biodiversity conservation if forests are appropriately managed. Within forests, structural and habitat diversity are known to be critical for biodiversity but pragmatic management recommendations are lacking. We make a comprehensive assessment of the effects of habitat variables on bird populations using data from over 4000 ha of forested landscape. We combine high-resolution remote sensing data with comprehensive management databases to classify habitat attributes and measure the response of six taxonomic and functional diversity metrics: species richness, Shannon diversity, functional richness, functional evenness, functional divergence, and functional dispersion. We use a novel approach that combines hierarchical partitioning analysis with linear models to determine the relative importance of different habitat variables for each bird diversity metric. The age class of forest stands was consistently the most important variable across all bird diversity metrics, outperforming other structural measures such as horizontal and vertical heterogeneity and canopy density. Shrub density and gap fraction were each significantly associated with one bird diversity metric. In contrast, variables describing within-stand structural heterogeneity (vertical and horizontal) were generally less important while tree species identity (e.g., conifer or broadleaved) was not significant for any bird diversity metric. Each of the six bird diversity metrics had different patterns of independent variable importance and significance, emphasizing the need to consider multiple diversity metrics in biodiversity assessments. Similarly, the optimal resolution for remote sensing metrics varied between structural variables and bird diversity metrics, suggesting that the use of remote sensing data in biodiversity studies could be greatly improved by first exploring different resolutions and data aggregations. Based on the results from this comprehensive study, we recommend that managers focus on creating habitat diversity at the between-, rather than exclusively within-stand scale, such as by creating a matrix of different age classes, to maximize bird diversity. This recommendation for forest managers is powerful yet pragmatic in its simplicity.

Thermoregulatory opportunity and competition act independently on life‐history traits in aquatic ectotherms

Abstract Many ectothermic species use behavioural thermoregulation to reduce their exposure to climate change. The buffering effect of behavioural thermoregulation will depend on the time available for an ectotherm to attain a body temperature within the target range, that is, the ‘opportunity for thermoregulation’. Behavioural thermoregulation can be further altered by the presence of competitors. Spatiotemporal dynamics in opportunity for thermoregulation and competition intensity should affect variation in ectotherm life history and fitness; however, experimental support for their joint influence is missing. I tested this prediction in a mesocosm experiment using larvae of two sympatric amphibians, the alpine newt Ichthyosaura alpestris and the common newt Lissotriton vulgaris. Thermoregulatory opportunities and competition intensities were manipulated by exposing larvae to warmer temperatures and altering densities of con‐ and heterospecifics. Life‐history traits were monitored until metamorphic emergence from the water. Thermoregulatory opportunity accelerated differentiation rate and time to metamorphic emergence, while both intra‐ and interspecific competition affected growth rate and mass at emergence. The impact of competition on survival and injury rates varied between taxa. Thermoregulatory opportunity and competition impacted larval life‐history traits in an additive fashion. Suitable conditions for thermoregulation allowed larvae to shorten their developmental period, and thus escape from the aquatic environment earlier than in thermoregulatory challenging environment. Competition was a primary determinant of mass at emergence, which is an important fitness correlate in amphibians. Species‐specific survival under competition may contribute to variation in habitat requirements between sympatric taxa. To sum up, predictions on the impact of climate change on ectotherm life histories require information not only about environmental temperatures, but also about species thermoregulatory opportunities and competitive abilities. Thermoregulatory opportunity is an ecologically relevant habitat property not only for basking ectotherms but also for taxa using less conspicuous thermoregulatory adjustments. The influence of thermoregulatory opportunity and competitive interactions on life histories varies among traits, indicating the need for a multi‐trait approach for understanding the complex influences of environmental change on ectotherm population dynamics and species interactions. Read the free Plain Language Summary for this article on the Journal blog.

Spatial Aggregation and Biometric Variability of the Grass Calamagrostis epigejos (L.) Roth during Different Expansion Stages in Mesic Mountain Meadows

Calamagrostis epigejos (L.) Roth is one of the most expansive clonal grass species. Despite many publications about its biology, the expansive mechanism of C. epigejos is relatively unknown. Therefore, the aim of this study was to determine: I. the dependency between Calamagrostis epigejos ramet density, habitat properties, and the biometric variability of the species; II. the relation between clone architecture and the diversity parameters and the productivity of grassland biocoenoses; III. the expansion strategy of Calamagrostis epigejos within mesic meadows, representing three stages of degradation. The research was conducted in the Central Sudetes (SW Poland). Ten transects were selected for the study, each representing Arrhenatheretalia-type meadows with patches degraded as a result of Calamagrostis epigejos expansion:initial, intermediate, and advanced. The phalanx strategy was observed within the studied range of the Calamagrostis epigejos expansion in the mesic mountain meadows. The study showed no relation between the Calamagrostis epigejos expansion and the phenomenon of ramet self-thinning, though it noted the influence of the habitat on the variability of its biometric features.

Sex-based differences in the use of post-fire habitats by invasive cane toads (Rhinella marina)

Wildfires can modify habitat attributes, and those changes may differentially affect males versus females within a species if there is pre-existing niche divergence between the sexes. We used radio-tracking and dissections to study invasive cane toads (Rhinella marina), and performed transect counts on native frogs and cane toads 12 months after extensive fires in forests of eastern Australia. Both toads and native frogs were encountered more frequently in burned sites than in unburned sites. Most microhabitat features were similar between burned versus unburned areas, but fire had differential impacts on the ecology of male versus female toads. In burned areas females were less numerous but were larger, in better body condition, and had consumed more prey (especially, coleopterans and myriapods). The impact of fire on attributes of retreat-sites (e.g., temperature, density of vegetation cover) also differed between the sexes. More generally, intraspecific divergence in ecological traits within a species (as a function of body size as well as sex) may translate into substantial divergences in the impacts of habitat change.

Move, migrate, or tolerate: Quantifying three tactics for cold‐water fish coping with warm summers in a large river

AbstractMainstem rivers are important for provisioning cold‐water fisheries and often support fluvial life histories that grow much larger than resident counterparts in tributaries. However, mainstem rivers are also warmer than tributaries during summer and more tightly coupled to regional climate. A key challenge is to understand how fluvial life histories cope with summer temperatures in mainstem rivers, both now and in a warmer future. Here, we outline three options: tolerance, exploitation of cool microhabitats, or migration to cooler tributaries. We quantified the relative prevalence of these responses in the wild using a Lagrangian approach. Specifically, we used temperature transmitting radio‐tags to track coastal cutthroat trout (Oncorhynchus clarkii clarkii) habitat use across 100 km of the Willamette River, which exhibited a maximum temperature of 22°C. We found that 89.8% of fish stayed in the mainstem and tolerated high temperatures; 6.5% of the population exploited cool floodplain alcoves; and 3.7% moved into a cool tributary, the McKenzie River. We also found that on average, larger fish opted to use cold‐water refuge habitats rather than tolerate mainstem river temperatures. The expression of all three coping tactics suggests this population has adaptive capacity to respond to future warming. More work is needed to understand how the relative expression of these tactics change depending on the severity of heat stress or nontemperature attributes of mainstem, floodplain, and tributary habitat.

Physical Habitat Attributes Influence Diversity and Turnover of Waterbirds Wintering at Wetlands on Central Asian and East Asian-Australasian Flyways in Eastern India

Physical Habitat Attributes Influence Diversity and Turnover of Waterbirds Wintering at Wetlands on Central Asian and East Asian-Australasian Flyways in Eastern India

Applying Ecological Succession Theory to Birds in Solar Parks: An Approach to Address Protection and Planning

Renewable energy production will require large areas of land; production sites should be designed to include biodiversity conservation. Guidance for decision-makers on reasonable coexistence is needed. We use time-series data alongside a meta-study on birds in solar parks, utilizing succession theory to indicate which bird groups can thrive in solar parks. Using an evidence-based and interdisciplinary approach, we documented biodiversity and conditions at a 6 ha site in the newly created post-mining landscape of Lusatia, Germany, for 16 years, grouping avian species depending on the ecosystem state in which they were observed. In a key mid-period of early succession lasting eight years, the avifauna was characterized by successional groups 2, herbaceous plant-preferring, ground-breeding species; and 3, open shrub-preferring species. The preceding and following groups were: (1) pioneer bird species that prefer open ground; and (4), pre-forest species. Comparison of these data with available bird monitoring in solar parks showed that bird species of groups 2 and 3 can also successfully settle in open-space solar parks that have some natural habitat attributes, whereas this is hardly possible for the preceding and following groups. Using this information, opportunities for habitat improvement are facilitated, and potential conflicts can be addressed more purposefully.

Estimating the average distribution of Antarctic krill Euphausia superba at the northern Antarctic Peninsula during austral summer and winter

This study was performed to aid the management of the fishery for Antarctic krill Euphausia superba. Krill are an important component of the Antarctic marine ecosystem, providing a key food source for many marine predators. Additionally, krill are the target of the largest commercial fishery in the Southern Ocean, for which annual catches have been increasing and concentrating in recent years. The krill fishery is managed by the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR), which has endorsed a new management framework that requires information about the spatial distribution and biomass of krill. Here, we use krill density estimates from acoustic surveys and a GAMM framework to model habitat properties associated with high krill biomass during summer and winter in the northern Antarctic Peninsula region, an area important to the commercial fishery. Our models show elevated krill density associated with the shelf break, increased sea surface temperature, moderate chlorophyll-a concentration and increased salinity. During winter, our models show associations with shallow waters (< 1500 m) with low sea-ice concentration, medium sea-level anomaly and medium current speed. Our models predict temporal averages of the distribution and density of krill, which can be used to aid CCAMLR’s revised ecosystem approach to fisheries management. Our models have the potential to help in the spatial and temporal design of future acoustic surveys that would preclude the need for modelled extrapolations. We highlight that the ecosystem approach to fisheries management of krill critically depends upon such field observations at relevant spatial and temporal scales.

Bird Migration at the Edge – Geographic and Anthropogenic Factors but Not Habitat Properties Drive Season-Specific Spatial Stopover Distributions Near Wide Ecological Barriers

Stopping-over is critical for migrating birds. Yet, our knowledge of bird stopover distributions and their mechanisms near wide ecological barriers is limited. Using low elevation scans of three weather radars covering 81,343 km2, we quantified large-scale bird departure patterns during spring and autumn (2014–2018) in between two major ecological barriers, the Sahara Desert and Mediterranean Sea. Boosted Regression Tree models revealed that bird distributions differed between the seasons, with higher densities in the desert and its edge, as well as inland from the sea, during spring and a predominantly coastal distribution in the autumn. Bird distributions were primarily associated with broad-scale geographic and anthropogenic factors rather than individual fine-scale habitat types. Notably, artificial light at night strongly correlated with high densities of migrants, especially in the autumn. Autumn migrants also selected sites located close to water sources. Our findings substantially advance the understanding of bird migration ecology near ecological barriers and facilitate informed conservation efforts in a highly populated region by identifying a few high-priority stopover areas of migrating birds.

Functional Roles and Ecological Importance of Small Cetaceans in Aquatic Ecosystems

Small cetaceans (dolphins, porpoises, and small toothed whales) occur from the poles to the tropics, and from freshwater habitats to the open ocean. Most ecological research has focused on the influence of abiotic factors on the abundance, distribution, and behavior of these species. The ecological impacts of small cetaceans on communities and ecosystems remain poorly quantified. Their movement patterns, often high local and regional abundances across a range of ecosystems, and high metabolic rates suggest that small cetaceans could have large effects on ecosystem structure, dynamics, and function through a variety of mechanisms. These include top-down (e.g., direct predation and risk effects) and bottom-up effects (e.g., translocation of nutrients within and across ecosystems), but also behavior-mediated processes where these predators can facilitate access to resources to other predators or modify the physical properties of habitat (e.g., bioturbation). Most small cetaceans can be consumed by other marine predators, particularly killer whales (Orcinus orca) and large sharks. Although consumption rates of small cetaceans can be high, there is a paucity of information on their effects on population sizes or behaviors of their prey. Mass-balance ecosystem models suggest that small cetaceans may impact the populations of short-lived prey species (particularly fish and cephalopods), but other factors (e.g., eutrophication and fisheries) also affect ecosystem functioning and population trends. Delphinids can also mediate the translocation and recycling of limiting nutrients between spatially distinct ecosystems on a diel basis. Despite intriguing possibilities, large gaps remain in our understanding of the roles and importance of small cetaceans in aquatic ecosystems, both marine and freshwater.

Multi‐scale habitat selection by a cryptic, critically endangered grassland bird—The Plains‐wanderer (Pedionomus torquatus): Implications for habitat management and conservation

AbstractOur understanding of the habitat needs of grassland fauna is often incomplete because of their cryptic behaviour. This presents a barrier to identifying important habitat attributes, whether these change at different spatial scales, and how this informs management decisions. Here, we use a critically endangered bird, the Plains‐wanderer (Pedionomus torquatus, Pedionomidae), as an exemplar of the challenge of managing grasslands for cryptic species. Until now, almost all ecological knowledge of Plains‐wanderers has come from the detection of nocturnally roosting individuals and habitat assessments at fine‐scales that indicate open swards are preferred habitat. We GPS‐tracked 13 adult Plains‐wanderers to better understand diurnal habitat utilization in native grasslands of south‐eastern Australia. Using these data, we assessed whether Plains‐wanderers select for different habitat attributes during the day and night, and whether this varied according to spatial scale. At the fine‐scale (&lt; 1 ha), daytime foraging occurred in denser swards than those of nocturnal roosting sites. At the patch‐scale (1–50 ha), Plains‐wanderers selected for denser vegetation, with higher grass and lichen cover, whilst avoiding areas where structure was impacted by a high exotic plant cover. Plains‐wanderers did not select habitat based on grassland type at the landscape‐scale (&gt;100 ha). We demonstrate that Plains‐wanderers require grasslands with both open and denser swards to support foraging and roosting. In doing so, we address the biases associated with habitat assessments based on roost‐only locations and extend known habitat associations critical to the successful management of the species. Our findings highlight that a precautionary approach to the classification of habitat requirements is warranted when uncertainty around habitat use of cryptic grassland fauna exists.

Environmental stressors alter multiple determinants of individual reproductive output in the acid‐tolerant mayfly Leptophlebia vespertina

Abstract1. Environmental stressors such as acidification modify community composition in freshwater habitats through their direct and indirect effects on individuals. However, the effect of acidification on various aspects of individual fitness is poorly known in aquatic insects, a key group in many freshwater habitats.2. Here, the influence of acidification (acidity and Al toxicity), food quality and habitat properties on the reproduction of an acid‐tolerant mayfly Leptophlebia vespertina (Linnaeus, 1758) in a group of Central European lakes is explored. The focus is on last‐instar larvae as the short‐lived, semelparous adults cannot mitigate stress experienced by the larvae.3. It is shown that the environment affects multiple determinants of individual reproductive output both directly by affecting body size and fecundity in last‐instar larvae, and indirectly by releasing the larvae from density dependence. Populations tended to be denser in more acidic sites and individuals in denser populations were substantially smaller and had lower size‐dependent fecundity and reproductive effort. All else being equal, larvae from colder sites were larger, suggesting an important role of the temperature‐size rule in this species. Size‐dependent fecundity and reproductive effort increased with better food conditions as expected, but neither reproductive measure was affected by acidity or temperature. Finally, a weak egg size‐number trade‐off with slightly smaller eggs in more fecund females was detected.4. These results imply that indirect ecological feedbacks and food quality, rather than the direct effects of stressful environment, may dominate the effects of environmental stressors on the reproductive output of acid‐tolerant species such as L. vespertina.

Physicochemical Characteristics of Aedes Mosquito Breeding Habitats in Suburban and Urban Areas of Kinshasa, Democratic Republic of the Congo

BackgroundThe knowledge of key elements of the ecosystem affecting mosquito distribution and their population dynamics is essential for designing mosquito-borne disease interventions. The present study characterized the physicochemical properties ofAedesmosquito breeding habitats in Democratic Republic of the Congo.MethodsA cross-sectional survey was carried out in Kinshasa, from February to April 2021. The physicochemical characteristics of the natural and artificial aquatic habitats ofAedeswere measured using a multiparametric device.ResultsOut of 438 breeding habitats inspected, 273 (62.3%) contained mosquito larvae. TheAedesmosquitoes identified in 76.19% of positive breeding sites wereAedes albopictus(67.30%) andAedes aegypti(37.98%). The median values of dissolved oxygen (DO) (1.0), turbidity (19.15), and salinity (0.115) in water breeding sites ofAedeswere respectively 0.8, 55.0, and 0.29 inCulexbreeding sites (p&amp;lt; 0.05). The physicochemical characteristics of the breeding habitat forAe. aegyptiandAe. albopictuswere almost identical. In urban areas, the median temperature was 29.82 while it was 29.60 in suburban areas (p&amp;lt; 0.05). Significantly, the salinity was higher in bamboo and metal containers while DO was higher in tins. After analysis using simple linear regression, total dissolved solids (r = 0.23;p= 0.000), conductivity (r = 0.23), salinity (r = 0.23), and temperature (r = 0.13) were associated with larval density (p&amp;lt; 0.05). In the final model (r = 0.30,p= 0.01), salinity (r = 0.23) and DO (r = 0.138) adjusted to temperature, pH, and turbidity were associated positively to larvae density.ConclusionTheAedesbreeding sites and mosquito density were significantly influenced by water salinity, DO, temperature, pH, and turbidity.

Assessing the effects of large herbivores on the three-dimensional structure of temperate forests using terrestrial laser scanning

Three-dimensional (3D) vegetation structure is vital in maintaining the functions of forest ecosystems and species diversity. Temperate forests of Northeast Asia support a variety of fauna but is also affected by large herbivore disturbances or management practice (e.g., livestock grazing), resulting in varying degrees of habitat degradation and fragmentation in many areas. However, traditional methods lack the quantification of 3D vegetation structure at a fine scale, which makes it difficult to obtain complete and accurate detailed data on the multi-level structure below the canopy and limits our understanding of the impact of disturbance on habitat quality and species diversity. In this study, terrestrial laser scanning (TLS) data were used to quantify the 3D habitat structural characteristics of different stand types affected by forest management or large herbivore activities (deer-browsed forest, livestock-grazed forest, secondary forest, and mixed forest) in Northeast China. TLS-derived parameters in this study revealed the subtle changes of habitat structures below the canopy: 1) livestock-grazed forest had a much lower canopy height, tree number, and stem volume than that of the other stand types; 2) the vegetation area index (VAI) of low canopy height (0–5 m) in livestock-grazed forest and deer-browsed forest were significantly lower than those in secondary and mixed forest with less disturbance; 3) intensive large herbivores activities led to the larger understory gaps and visibility in livestock-grazed and deer-browsed forest. TLS-derived parameters in this study are implicated in wildlife habitat selection and fitness, which contribute to revealing fine scale habitat structure-species diversity relationships. In forest management, it is proposed to use TLS to quantify the structural and functional attributes of habitats from a new perspective, thus guiding conservation practices at local scale to balance the relationship between plants and animals.

Complex effects of acidification, habitat properties and fish stock on littoral macroinvertebrate assemblages in montane standing waters

Littoral macroinvertebrates in acidified waterbodies are affected by the interaction of acidification and local environmental conditions. Understanding the interplay of these factors in the structuring of communities is essential for interpreting responses to and/or recovery from acidification. Here, we analyse the species composition and richness of littoral macroinvertebrates in a range of acidified montane standing waters in relation to water chemistry, littoral characteristics and fish stock. The main species composition gradients were related to pH and conductivity; however, considerable variation along these gradients was associated with local habitat characteristics (changing water levels and littoral structure) and concentration of ionic aluminium and dissolved organic carbon. Although fish stock effects were confounded by correlated acidity, we observed a significant decline in abundance of macroinvertebrates vulnerable to fish predation at sites with fish stock. Overall, littoral macroinvertebrates of acidic waterbodies were diverse due to the heterogeneity of local habitat properties, despite they were dominated by acid-tolerant species. Acidic humic sites with dense, heterogeneous littoral vegetation were species-rich, hosting numerous habitat specialists and rare species, while chronically acidified lakes with high aluminium concentrations and sparse littoral vegetation had species-poor assemblages, characteristic of strong acid-stress. Water level manipulation resulted in serious assemblage impoverishment, overriding the effects of more favourable water chemistry. This study shows that the littoral fauna of acidic waterbodies is structured by complex effects induced by local factors in addition to acidity, resulting in acid-stressed assemblages with relatively high variability, emphasising a need to analyse local habitat factors when evaluating the impact of acidification on macroinvertebrates.

Tropicalization unlocks novel trophic pathways and enhances secondary productivity in temperate reefs

Abstract The structure of ecological communities is rapidly changing across the globe due to climate‐mediated shifts in species distributions, with novel ecosystem states emerging as new species become dominant. While it is clear that such changes restructure habitat properties and their associated assemblages, how new nutritional resources and consumers may affect the ecosystem trophic structure and energetic dynamics remains poorly resolved. Here, we investigate how the reconfiguration of tropicalized reefs—that is, temperate ecosystems receiving an influx of tropical species—affects the availability of nutritional resources and energy flow through herbivore‐based trophic pathways. To do so, we quantified changes in algal and detrital resources along a tropicalization gradient in eastern Australia. We also estimated energy flow towards herbivorous fishes by quantifying their standing biomass (kg/ha), productivity (kg ha−1 day−1), and biomass turnover (% day−1), using an individual‐level modelling approach that combines estimates of fish growth rates and mortality. Along the gradient, tropicalized reefs had relatively higher amounts of palatable algal turfs and detrital particulates compared to non‐tropicalized sites. Feeding intensity by herbivorous fishes was also c. 400 times higher on tropicalized reefs, with tropical turf‐cropping surgeon fishes being responsible for &gt;98% of the feeding rates. Turf‐driven trophic pathways underpinned virtual all (&gt;99%) of the biomass produced by tropical fishes, which contributed up to 63% of the total herbivorous fish standing biomass and 86% of the productivity despite only representing 35% of the abundance. Turfs also fuelled most of the secondary productivity of tropical fishes on tropicalized reefs across Australia's western tropical–temperate transition zone, although their overall productivity was ~5 times lower. This is possibly due to turfs there containing elevated sediment loads, which dilute the nutritional quality of turf‐based resources, as well as other differences in the biogeographical context. We propose that algal turfs are central drivers of ecosystem energetic shifts on temperate reefs as they become tropicalized because they support novel algal and detrital trophic pathways that enhance secondary productivity and biomass turnover. Our results also suggest that turf characteristics such as organic content or sediment load may emerge as increasingly important drivers of energy flow in temperate locations where turfs dominate benthic cover. A free Plain Language Summary can be found within the Supporting Information of this article.

Considerations in the protection of marsupial gliders and other mature-forest dependent fauna in areas of intensive logging in the tall forests of Victoria, Australia

Context The tall forests of Victoria, Australia, which are available for logging, are foreshadowed to be converted from mature forest to hostile environments for mature-forest dependent species by 2030. This has occurred within a 60-year time-frame since the advent of industrial-scale logging in the region. In this light, Protection Areas (PAs) of approximately 100 ha have been implemented to protect habitat with high density populations of Yellow-bellied Gliders (Petaurus australis) and Southern Greater Gliders (Petauroides volans). Aims and methods Ten considerations are provided to guide location and design of PAs, and to provide set asides and other forms of protection for mature-forest dependent species in the context of the temporal and spatial scale of logging activity. Key results Considerations are grouped into Overall approach (precautionary), Survey records and habitat attributes (occurrence, habitat, vegetation types), Size and shape considerations (edge and fragmentation effects); Management history (logging and fire), and Boundary considerations (context and conditions). In addition, set asides encompassing home ranges; and high levels of basal area retention, are also required in the remainder of planned logging coupes. Conclusions Addressing these considerations in PAs, in set asides and in retention will provide some protection for mature-forest dependent species, but will be insufficient without ecologically sustainable forest management at the coupe level, for the sustained yield of all habitat components of these forests. Implications The conservation of mature-forest dependent species in the context of an ongoing timber industry requires logging return times well beyond current expectations, resulting in a substantial reduction in resource commitment to industry.

A new deployable pantographic lunar habitat

Deployable lunar structures have been and are being developed as an appropriate solution to the volumetric limitations of cargo mission flights. A deployable lunar habitat consisting of linear and planar elements connected through simple movable joints is introduced. This new structure is made of some linear units consisting of two types of scissor-like elements (SLE): 1) a modified polar scissor-like element and 2) a closed-loop of angulated scissor-like elements. After conducting theoretical research on lunar habitats, the evaluation criteria of transformable lunar structures are derived and then many new concepts are evaluated. The design considerations of such structures are discussed, and a proper form for these habitat types is selected. An experimental study is run to assess the best deployment strategy for the whole structure. By introducing the dimensional properties of the lunar habitats through physical and digital modeling process per crewmember, the derived alternatives from the previous stage are analyzed and the best transformation strategy that meets the aforementioned considerations is developed. Providing relatively high degrees of protection against environmental hazards through the combination of rigid plates with membrane, this proposed structure reduces the required extravehicular activity (EVA) time for assembly because of its quick and simple deployment mechanism. The folded state of the structure provides a low volume for the integration of subsystems.

The ecological niche and conservation value of Central European grassland orthopterans: A quantitative approach

The ongoing biodiversity decline across taxonomic groups, including insects, is tightly related to land-use changes and habitat degradation. To assess habitat quality, proper bioindicators that allow efficient monitoring of temporal changes in habitat properties and help to understand the role of anthropogenic activities in shaping habitat characteristics, are needed. Orthopterans have been previously proposed as promising bioindicators for grassland ecosystems; however, comprehensive quantitative information on their habitat preferences is lacking, which hinders full utilization of their bioindication potential. In this study, we surveyed orthopteran assemblages and quantified local environmental conditions at 476 grassland sites in Central Europe. To model orthopteran habitat preferences, the Maxent approach was employed, which allowed us to detect continuous species responses to particular habitat characteristics (moisture, vegetation cover, vegetation height, average seasonal temperature, and direct radiation). We calculated ecological niche indices describing niche widths, species optima, and the relative importance of particular environmental variables for a total of 38 analysed species. Evaluation of final Maxent models showed that their predictive power was high for the great majority of investigated species. Red-listed species had significantly narrower niches compared to unlisted orthopterans. In addition, application of the developed quantitative ecological niche indices for ecological and conservation studies was demonstrated on an independent, previously published dataset. The development of quantitative ecological niche indices coupled with the existing time- and cost-effective survey methods, also allowing adoption of citizen science approaches, makes orthopterans an optimal model insect group for assessment of grassland condition and conservation.

Habitat associations between Streptococcus bovis/equinus complex and Streptococcus phocae, the causative agents of strep syndrome in sea otters, and the marine environment

AbstractThe bacteria in the Streptococcus bovis/equinus complex (SBEC) and Streptococcus phocae have caused significant morbidity and mortality in northern sea otters (Enhydra lutris kenyoni). In order to illuminate the persistence and possible mechanisms of transmission of SBEC and S. phocae, the presence and absence of these bacteria were compared with 31 habitat attributes in Kachemak Bay and Resurrection Bay, Alaska. Bay mussels or water were collected at 1600‐m intervals around the perimeters of each bay and habitat attributes were recorded onsite and/or determined using ShoreZone. PCR was used to confirm the presence of bacteria, and presence was correlated with habitat attributes. Geographic spatial analysis revealed a cluster of low occurrence of both SBEC and S. phocae in an extremely shallow portion of Kachemak Bay that may be due to drying of the area between tide cycles. A cluster of high occurrence of S. phocae on the northeast side of the Kachemak Bay was identified that may be associated with harbor seal presence. No statistically significant clusters were found in Resurrection Bay. Habitat attributes (rockweed, eelgrass, habitat class, soft brown kelp and substrates of rock, sand and boulder) were found to be associated with presence of the target bacteria; however, relationships were not consistent with the bacteria or each bay. This could be due to the complexity of the relationship between SBEC and S. phocae and their environments, as well as intrinsic differences (such as nearshore temperatures) between Kachemak and Resurrection Bays.