Viability Of Species Research Articles

Respuesta de semillas de tres especies nativas altoandinas a diferentes condiciones de almacenamiento

To ensure the germination capability and viability of native tree species it is important to know the optimum conditions for seed storage in the long term. In response to this, we investigated the effect of seed storage on the germination, viability, and velocity of germination (VG) of Vallea stipularis, Hedyosmum luteynii and Oreopanax avicenniifolius. The seeds were collected in Llaviucu and Mazan forests in Cajas National Park and exposed to different treatments of seed storage: three levels of seed moisture content (initial, medium and low), two levels of temperature (10oC and room temperature) and three periods of storage (3, 6, and 12 months). The research revealed that seeds of V. stipularis stored at 10oC for 12 months had the lowest germination values, even null percentages; the more the seed viability and VG decreased when the time of seed storage increased. The seeds of H. luteynii showed high germination and viability up to 12 months of storage at 10oC, however, its germination was later and little synchronized. The room temperature did not work well for germination and VG for both these species, although, H. luteynii maintained its viability intact up to the last period of evaluation. O. avicenniifolius maintained at 10oC and room temperature its germination capacity up to 12 months but with a lower percentage. The knowledge generated contributes to better seed management in ex situ conservation programs and plant propagation for restoration.

Multi-scale habitat selection by Northern Goshawks (Accipiter gentilis) in a fire-prone forest

Increasing frequency and severity of wildfire may jeopardize persistence of large tracts of late seral forest, raising concerns over population viability of forest-dependent species like the Northern Goshawk (Accipiter gentilis). We tracked 20 adult Northern Goshawks with GPS loggers over 4 years to investigate roosting (nocturnal) and foraging (diurnal) habitat selection in a heterogeneously burned forest landscape of the Sierra Nevada mountains of California, United States. Goshawks selected late seral forest attributes for both roosting and foraging at multiple spatio-temporal scales, although at the finest (daily) scale, goshawks selected more diverse forest structure that included small trees and medium canopy cover. Less than 6% of roosts were in areas burned in the last 50 years and goshawks avoided areas burned at high severity when roosting and when foraging across spatial scales. Four goshawks (3 males, 1 female) undertook forays >5 km from their nest location, two of which forayed into burned areas during at least one season. High severity fire is likely to make forests unsuitable foraging or roosting habitat for Northern Goshawks, although lower severity fire may provide foraging opportunities for this generalist predator. Eighty percent of foraging space use and 87% of roost locations were considered high fire hazard potential, suggesting that goshawk habitat in western North America is likely to be reduced by predicted increases in fire frequency and severity in the region.

Predicting indirect effects of transportation network expansion on Asian elephants: Implications for environmental impact assessments

AbstractThe rapid proliferation of transportation networks (TNs) threatens the viability of species with wide geographic ranges via habitat fragmentation, road kill, and indirect socio‐ecological interactions. Environmental impact assessments of TNs are mostly descriptive and focus on the direct impacts of the linear features of TNs, while the indirect and cumulative impacts are largely neglected. Using spatially explicit data of elephant‐caused damage from 2012 to 2015 in southwest China, we quantified the barrier effects of TNs on Asian elephant populations and predicted future patterns of damage under a TN expansion scenario using maximum entropy algorithms. The TNs acted as a strong barrier for the elephants, even in herds that have inhabited highly fragmented landscapes for years. Overall damage patterns were highly asymmetric around roads, with only 18% of events occurring on the far side of roads (relative to the core home range). Models predicted that TN expansion would reduce elephant habitats, exacerbating herd isolation and human–elephant conflict locally. Thus, we suggest that future environmental impact assessments should integrate mitigation of indirect conflicts.Abstract in Chinese is available with online material.

Managing networked landscapes: conservation in a fragmented, regionally connected world

Ecological fragmentation coupled with changes in climate affects the viability of species and is likely to pose a serious threat for maintaining biodiversity, especially as biodiversity often depends on species ability to migrate between different ecological areas spanning multiple sociopolitical jurisdictions. To reduce the risk to biodiversity, there is a need for connected, interjurisdictional landscape management plans at regional levels. It is a key to identify how decision-makers collaborate and share knowledge, learn, and ultimately make decisions affecting species coexistence. Here, we present a model that mimics multiple political jurisdictions making decisions affecting species migration across a landscape. This management and species movement can be between nations, between public and private landowners, or any other scale of interjurisdictional management in between. The model we present here has direct application to the decisions that managers make regularly and draws upon anecdotal evidence from real-world case studies such as the removal of fences in the Great Limpopo Transfrontier Park in southern Africa, and cooperation to solve regional environmental dilemmas in Arizona between neighbors. Our results highlight the importance of social learning and networks and matching the scale of sociopolitical and ecological processes in order to reduce biodiversity loss. Further, we find that close-knit decision-makers, especially when learning/imitating management strategies the same way, are detrimental to countering biodiversity loss. Finally, our results indicate the importance of allowing decision-makers to have room for experimental, individual learning to broaden the set of management strategies existing within a system to reduce biodiversity loss.

Buildings provide vital habitat for little brown myotis (Myotis lucifugus) in a high‐elevation landscape

AbstractBats in North America are currently experiencing dramatic population declines due to the disease white‐nose syndrome. The long‐term viability of vulnerable species requires recognition of critical habitats, including those also occupied by humans. Our study aimed to quantify the importance of buildings to little brown myotis (Myotis lucifugus) in Yellowstone National Park, a high‐elevation landscape with relatively few human structures and abundant alternative roosting habitat. We measured roost preferences and thermoregulation in adult male and female bats roosting in buildings, trees, and rocks using temperature‐sensitive radio‐transmitters. We also studied microclimates within each roost type for comparison to roost preferences. We found reproductive females roosting in building attics on 84% of all possible days, while males roosted exclusively in rock crevices or in trees. This dichotomous roosting pattern reflected differences in roost microclimates. All roost types buffered bats from daily minimum ambient temperatures; however, buildings were more insulated from low ambient temperatures during the middle of the maternity season. Male bats roosting in rocks and trees predominantly thermoconformed to roost temperatures, while females roosting in buildings sustained higher body temperatures than males throughout the day. Pregnant and lactating females also used torpor frequently, with skin temperatures reaching <10°C, and a gestation period lasting 49–89 d. These results show that cool summer temperatures at high elevations present an energetic challenge to little brown myotis. Buildings provide critical habitat for reproductive females and likely allow for larger populations than would be possible in their absence, making these roosts a priority for long‐term conservation of this declining species.

The tiliroside derivative, 3-O-[(E)-(2-oxo-4-(p-tolyl) but–3–en–1–yl] kaempferol produced inhibition of neuroinflammation and activation of AMPK and Nrf2/HO-1 pathways in BV-2 microglia

Neuroinflammation is now widely accepted as an important pathophysiological mechanism in neurodegenerative disorders, thus providing a critical target for novel compounds. In this study, 3-O-[(E)-(2-oxo-4-(p-tolyl)but-3-en-1-yl] kaempferol (OTBK) prevented the production of pro-inflammatory mediators TNFα, IL-6, PGE2 and nitrite from BV-2 microglia activated with LPS and IFNγ. These effects were accompanied by reduction in the levels of pro-inflammatory proteins COX-2 and iNOS. Involvement of NF-κB in the anti-inflammatory activity of OTBK was evaluated in experiments showing that the compound prevented phosphorylation, nuclear accumulation and DNA binding of p65 sub-unit induced by stimulation of BV-2 microglia with LPS and IFNγ. Exposure of mouse hippocampal HT22 neurons to conditioned media from LPS + IFNγ-stimulated BV-2 cells resulted in reduced cell viability and generation of cellular reactive oxygen species. Interestingly, conditioned media from LPS/IFNγ–stimulated BV-2 cells which were treated with OTBK did not induce neuronal damage or oxidative stress. OTBK was shown to increase protein levels of phospho-AMPKα, Nrf2 and HO-1 in BV-2 microglia. It was further revealed that OTBK treatment increased Nrf2 DNA binding in BV-2 microglia. The actions of the compound on AMPKα and Nrf2 were shown to contribute to its anti-inflammatory activity as demonstrated by diminished activity in the presence of the AMPK antagonist dorsomorphin and Nrf2 inhibitor trigonelline. These results suggest that OTBK inhibits neuroinflammation through mechanisms that may involve activation of AMPKα and Nrf2 in BV-2 microglia.

Factors that affect the occupancy, activity and distribution patterns of Grammostola vachoni, an endemic tarantula from the austral mountains of Argentina

Activity and occupancy dynamics of spiders are topics that have received little attention and are compounded by anecdotal field data, especially in Theraphosidae that are generally nocturnal. Due to potential vulnerability outside their burrows, it is expected that individuals remain in the safety of their shelters most of the time and because their limited dispersal mechanism, usually by walking over short distances. Grammostola vachoni is an endemic tarantula from Argentina listed as Vulnerable specie by the IUCN. Changes in natural habitat of G. vachoni are detrimental for their survivorship. However, little is known about whether their occupancy dynamics and spatial distribution pattern are affected by different disturbances. In this study we evaluated whether disturbances in the natural habitat of G. vachoni affected the distribution patterns and adults abundance in different populations and determined activity patterns and refuge fidelity. It was observed that the spiders emerged after 9:30 pm and showed an exploratory behavior; females exhibited high refuge fidelity. Results showed that in disturbed habitats the spiders presented an aggregated distribution, whereas in undisturbed habitats spiders remained in settlements with greater distances between neighbors. Therefore, it can be concluded that the distribution patterns of G. vachoni are influenced by environmental disturbances to their natural habitat. These aspects are particularly important due to the conservation status of the spider, since the continual regression of mountain grassland in Argentina puts species viability at risk; especially in species with limited dispersal capability, a longer life cycle and sedentary habits such as G. vachoni.

Three-Dimensional Leukemia Co-Culture System for In Vitro High-Content Metabolomics Screening

Metabolomics is increasingly applied to investigate different individuals and time-dependent responses to environmental stimuli. Rapid data acquisition and improved detection limits of direct infusion mass spectrometry (DIMS) are paving the way for applications of metabolomics in preclinical screening, opening new opportunities in drug discovery and personalized medicine. Three-dimensional (3D) cell culture systems, which mimic the in vivo cell microenvironment, are well recognized as tissue and organ substitutes.Here, we investigated cell viability and induction of reactive oxygen species (ROS) in stromal cells cultured in various 3D systems as well as the standard monolayer culture to evaluate which system provides the most favorable growing conditions. The selected 3D system was then tested for use in 3D co-culture of leukemia and stromal cells for DIMS-based high-throughput/high-content metabolic drug screens.The NanobioMatrix–poly(ε-caprolactone) (NBM–PCL) scaffold resulted in the lowest ROS production, supported rapid cell proliferation, and was suitable for the 96- and 384-well plate formats. Doxorubicin treatment in leukemia co-cultured with stromal cells induced some unique metabolic responses that drastically differed from those observed in leukemia cells alone. The DIMS results also showed that the drug-induced metabolic modulations in both normal and cancer cells were weakened by co-culturing even at high treatment doses, thereby demonstrating the value of the 3D co-culture high-content metabolic drug screen. In conclusion, we optimized a high sample throughput method for 3D co-culture with a DIMS-based high-content metabolic drug screen and drug development.

Disentangling the effects of environmental conditions on wintering and breeding grounds on age‐specific survival rates in a trans‐Saharan migratory raptor

Migratory species are subject to environmental variability occurring on breeding and wintering grounds. Estimating the relative contribution of environmental factors experienced sequentially during breeding and wintering, and their potential interaction, to the variation of survival is crucial to predict population viability of migratory species. Here we investigated this issue for the Montagu's harrierCircus pygargus, a trans‐Saharan migrant. We analysed capture–recapture data from a 29‐year long monitoring of wing‐tagged offspring and adults at two study sites in France (Rochefort‐RO and Maine‐et‐Loire‐ML). The study period covers a climatic shift occurring in the Sahel with increasing rainfall following a period of droughts (Sahel greening). We found that harriers’ adult survival in RO (between 1988 and 2005) varied over time and was sensitive to the interaction between the amount of rainfall in the Sahel and the annual mean breeding success, two proxies of prey availability. The occurrence of adverse conditions on breeding and wintering grounds in the same year decreased survival from 0.70–0.77 to 0.48 ± 0.05. Juvenile survival in RO was slightly more sensitive to conditions in Europe than in the Sahel. Unexpectedly, lower survival rates were found in years with higher mean breeding success, suggesting compensatory density feedbacks may operate. By contrast, adult survival in ML, monitored between 1999 and 2017, was higher compared to RO (0.76 ± 0.03 versus 0.66 ± 0.02), remained constant and unaffected by any proxy of prey availability. This difference seems consistent with the fact that harriers in ML experienced better and especially less variable environmental conditions during breeding and wintering seasons compared to RO. Overall, we showed that survival of a migratory bird is sensitive to the level of variability in environmental conditions and that adverse conditions on wintering grounds can amplify the negative effects of conditions during the previous breeding season on birds’ survival.

Spore viability of microsporidian species isolated from gipsy moth larvae (Lymantria dispar) after long-term storage in liquid nitrogen

U radu se prikazuju rezultati preživljenja mikrosporidija izoliranih iz gubara (Lymantria dispar) nakon dugotrajne pohrane u tekućem dušiku. Infektivnost osam mikrosporidijskih L. dispar izolata testirano je na ličinkama gubara: Vairimorpha disparis, Nosema lymantriae, Nosema portugal, Nosema sp. (Poljska), Nosema sp. (Ebergassing), Nosema sp. (Njemačka), Nosema sp. (Schweinfurt) and Nosema sp. (Veslec). Preživljenje spora u tekućem dušiku detaljno je praćeno kod N. portugal i Nosema sp. (Ebergassing) koje su tako čuvane skoro 19 godina i aplicirane oralnom infekcijom i ponaosob na svaku pojedinu ličinku gubara. Ostalih 6 izolata aplicirano je površinskom kontaminacijom hranjivog supstrata, također oralnim infekcijskim putem. Od 8 mikrosporidijskih izolata apliciranih površinskom kontaminacijom samo kod 4 izolata, Vairimorpha disparis, Nosema lymantriae, Nosema sp. (Ebergassing) i Nosema sp. (Poljska), došlo je do uspješne infekcije ličinki gubara. Dok je kod svih testiranih ličinki (100%) uspješno realizirana infekcija sporama prve tri mikrosporidije, tek 21,1% tretiranih ličinki uspješno je inficirano sporama Nosema sp. (Poljska). Na kraju inkubacijskog razdoblja, kod svih ličinki inficiranih sa sva 4 izolata disekcijom je utvrđen visok stupanj zaraze; tkiva su bila ispunjena sporama. Mikroskopska pretraga ličinki L. dispar individualno tretiranih sporama Nosema portugal uz tri različite doze (100, 1000 i 10000 spora) pokazala je da su spore N. portugal izgubile infektivnost nakon 19 godina pohrane u tekućem dušiku; niti jedna od testiranih ličinka nije bila zaražena. Naprotiv, spore Nosema sp. (Ebergassing) zadržale su infektivnost nakon istog razdoblja pohrane u tekućem dušiku od 18,75 godina. Niti jedna od testiranih ličinki nije zaražena nakon oralnog unosa od 100 spora. Oralna aplikacija od 1000 spora po ličniki rezultirala je ukupnom uspješnom infekcijom 4,1% ličinki, a aplikacija od 10000 spora s 68,8% inficiranih ličinki. U svim uspješnim slučajevima uspješno zaraženih ličinki, na kraju inkubacijskog razdoblja infekcija je bila dobro razvijena, a masno tijelo prepuno spora. Istraživanje je potvrdilo da je pohrana mikrosporidija Nosema i Vairimorpha vrsta i domaćina iz reda leptira prikladna opcija za dugotrajno čuvanje izolata. Spore su preživjele i do 18 i pola godina, iako je tijekom eksperimenta zamijećen i značajan pad njihove infektivnosti. U pojedinim slučajevima spore su odumrle već nakon 7 godina pohrane u tekućem dušiku. Preporuka je da prilikom skladištenja i pohrane mikrosporidijskih izolata u tekućem dušiku svakih 5 godina repozitorij obnavlja svježim izolatima. Materijal koji se dulje vrijeme skladišti u tekućem dušiku nije prikladan i ne bi se smio koristiti u infektološkim testovima.

Gut microbiota and their putative metabolic functions in fragmented Bengal tiger population of Nepal.

Bengal tigers (Panthera tigris tigris) serve a pivotal role as an apex predator in forest ecosystems. To increase our knowledge on factors impacting the viability and health of this endangered species, we studied the gut microbiota in 32 individual Bengal tigers from three geographically separated areas (Chitwan National Park (CNP), Bardia National Park (BNP) and Suklaphanta Wildlife Reserve (SWR)) in Nepal, using noninvasive genetic sampling methods. Gut microbiota influence the immune system, impact various physiological functions, and modulates metabolic reactions, that ultimately impact the host health, behavior and development. Across the tiger populations in Nepal, we found significant differences in the composition of microbial communities based on their geographic locations. Specifically, we detected significant differences between CNP and the other two protected areas (CNP vs BNP: pseudo t = 1.944, P = 0.006; CNP vs SWR: pseudo t = 1.9942, P = 0.0071), but no differences between BNP and SWR. This mirrors what has been found for tiger gene flow in the same populations, suggesting gut microbiota composition and host gene flow may be linked. Furthermore, predictive metagenome functional content analysis (PICRUSt) revealed a higher functional enrichment and diversity for significant gut microbiota in the Chitwan tiger population and the lowest enrichment and diversity in Suklaphanta. The CNP tiger population contained higher proportions of microbiota that are associated with predicted functions relevant for metabolism of amino acid, lipid, xenobiotics biodegradation, terpenoides and polyketides than the SWR population. We conclude the tiger population structure, gut microbiota profile and associated functional metabolic categories are correlated, with geographically most separated CNP and SWR tiger population having the most distinct and different host genotype and microbiota profiles. Our work dramatically expands the understanding of tiger microbiota in wild populations and provides a valuable case study on how to investigate genetic diversity at different hierarchical levels, including hosts as well as their microbial communities.

Spatial heterogeneity in climate change effects decouples the long-term dynamics of wild reindeer populations in the high Arctic.

The ‘Moran effect’ predicts that dynamics of populations of a species are synchronized over similar distances as their environmental drivers. Strong population synchrony reduces species viability, but spatial heterogeneity in density dependence, the environment, or its ecological responses may decouple dynamics in space, preventing extinctions. How such heterogeneity buffers impacts of global change on large‐scale population dynamics is not well studied. Here, we show that spatially autocorrelated fluctuations in annual winter weather synchronize wild reindeer dynamics across high‐Arctic Svalbard, while, paradoxically, spatial variation in winter climate trends contribute to diverging local population trajectories. Warmer summers have improved the carrying capacity and apparently led to increased total reindeer abundance. However, fluctuations in population size seem mainly driven by negative effects of stochastic winter rain‐on‐snow (ROS) events causing icing, with strongest effects at high densities. Count data for 10 reindeer populations 8–324 km apart suggested that density‐dependent ROS effects contributed to synchrony in population dynamics, mainly through spatially autocorrelated mortality. By comparing one coastal and one ‘continental’ reindeer population over four decades, we show that locally contrasting abundance trends can arise from spatial differences in climate change and responses to weather. The coastal population experienced a larger increase in ROS, and a stronger density‐dependent ROS effect on population growth rates, than the continental population. In contrast, the latter experienced stronger summer warming and showed the strongest positive response to summer temperatures. Accordingly, contrasting net effects of a recent climate regime shift—with increased ROS and harsher winters, yet higher summer temperatures and improved carrying capacity—led to negative and positive abundance trends in the coastal and continental population respectively. Thus, synchronized population fluctuations by climatic drivers can be buffered by spatial heterogeneity in the same drivers, as well as in the ecological responses, averaging out climate change effects at larger spatial scales.

Algorithms for Estimating Trends in Global Temperature Volatility

Trends in terrestrial temperature variability are perhaps more relevant for species viability than trends in mean temperature. In this paper, we develop methodology for estimating such trends using multi-resolution climate data from polar orbiting weather satellites. We derive two novel algorithms for computation that are tailored for dense, gridded observations over both space and time. We evaluate our methods with a simulation that mimics these data’s features and on a large, publicly available, global temperature dataset with the eventual goal of tracking trends in cloud reflectance temperature variability.

An agonist of the MscL channel affects multiple bacterial species and increases membrane permeability and potency of common antibiotics.

The bacterial MscL channel normally functions as an emergency release valve discharging cytoplasmic solutes upon osmotic stress. The channel opens and passes molecules up to 30Å and its pore is the largest of any gated channel. Opening the MscL pore inappropriately is detrimental to the bacterial cell, suggesting MscL as a potential novel drug target. A small-molecule compound, 011A, has been shown to increase sensitivity of the Escherichia coli MscL channel, slow growth, and even decrease viability of quiescent cultures. The mscL gene is highly conserved and found in the vast majority of bacterial species, including pathogens. Here, we test the hypothesis that 011A can influence the growth and viability of other bacterial species, specifically Staphylococcus aureus and Mycobacterium smegmatis, in a MscL-dependent manner. Furthermore, we demonstrate that the 011A compound can increase potency of other antibiotics, presumably by permeabilizing the membrane and allowing easier access of the antibiotic into the cytoplasm. Thus, MscL activators have potential as novel broad-spectrum antibiotics or adjuvants that work with antibiotics to selectively allow passage across bacterial membranes.

Changes in vascular plant species composition, top-soil and seed-bank along coppice rotation in an Ostrya carpinifolia forest

Ostrya carpinifolia forests are formations traditionally managed as coppice, with a high biodiversity that characterizes much of the Italian and Balkan low mountain and hill landscapes. Here, we analyze changes in vegetation, seed-bank, soil and litter at six different stages during the coppicing rotation and after 10 years of abandonment of an Ostrya carpinifolia forest located in the central Apennines. Data show that the dynamism characterizing this coenose during traditional coppice rotation alters after cessation of the management practices. Although from the phytosociological point of view all the forest stands belonged to the same association, the highest biodiversity was achieved in the early stages after cutting. This was ascribed to the canopy removal, which creates favourable conditions for the germination of pre-mantels and mantels species stored in the soil seed-bank, while suitable conditions for the nemoral flora are maintained around the tree stumps. In later years, a reduction of non-strictly forest species and an increase in the relative thicknesses of the more superficial top-soil horizons occurred, reaching the maximum around 18 years after cutting. With the abandonment, simplification of the top-soil morphology, total loss of seed bank viability and increase of open-environments species were observed.

Growth and viability of Lactobacillus acidophilus NRRL B-4495, Lactobacillus casei NRRL B-1922 and Lactobacillus plantarum NRRL B-4496 in milk supplemented with cysteine, ascorbic acid and tocopherols

The effect of three reducing agents (RAs), l-cysteine, ascorbic acid, and tocopherols, on the growth of Lactobacillus acidophilus, Lactobacillus casei, or Lactobacillus plantarum during milk fermentation was evaluated. pH, redox potential, and Lactobacillus counts were determined until pH ≈ 4.6. Further, the study aimed to optimise the concentration of the RAs by formulating the fermented milks with the same RA at different concentrations (0–250 mg L−1 for l-cysteine or ascorbic acid and 0–15 mg L−1 for tocopherols) using a Box–Behnken experimental design. After 45 days of refrigerated storage, the viability of each Lactobacillus species was maximised. We observed that the effect of RA on Lactobacillus is species dependent; ascorbic acid and tocopherols reduced the fermentation time (29%–43%), whereas l-cysteine enhanced the Lactobacillus counts (≥1 log10 cfu mL−1). Lactobacillus species differ in terms of oxygen sensitivity.

The agro-enabled urban revolution, pesticides, politics, and popular culture: a case study of land use, birds, and insecticides in the USA

Urbanization is an inevitable process in human civilization. When populations expand, socio-economic and political dynamics typically shift from agricultural predominance to one of industry and services. Accordingly, agrarian societies transform from diffuse rural communities to dense urban centers. By 2050, the world’s population is projected to reach 9.1 billion, with the urban population growing from 50 to 70%. Inevitably, this ever-expanding urban frontier encroaches along the human-ecological interface, creating a challenge for conservation and biodiversity. For the past 30 years, agricultural cropland area in the USA has remained fairly constant, despite significant population growth over the same time period. Thus, agricultural production in America has more than kept pace with rapid population growth and global export demand without increasing the farmland footprint at the expense of wildlife habitat. This is primarily due to considerable advances made in pesticide development, safety, and regulation, coupled with soil conservation and genetically modified crops. Still, the potential contribution of agriculture to ecosystem impairment remains contentious, particularly with regard to current use of pesticides. Recently, significant focus has been placed on the state of bird populations in the USA. Many species are considered imperiled, and this is often attributed in the popular media to pesticide use. However, focusing solely on the agricultural/chemical story as a significant driver of species viability and ecological risk within the broader biodiversity and conservation narrative lacks context and perspective. Moreover, the hypothesis that pesticides are indirectly affecting bird population status via reductions in food resources should be considered with caution and within the context of other likely causes. This work explores the dynamics between historical land use, human-controlled activity, and bird population trends from a holistic perspective within the USA. The aim is to provide context, developed from a relative comparison of potential contributing factors, in order to help inform discussion and foster dialogue between industry, academia, government, non-governmental organizations, and the public.

Macroinvertebrate Foraging on Larval Ambystoma maculatum across Ontogeny

Understanding community interactions, such as predator–prey dynamics, is vital for determining species viability. Outside of larger macroinvertebrate predators, such as crayfish and dragonfly larva...

Seed viability of some species of stipa l

In territory of Mongolia growing the 17 species of Stipa type. The more than 3000 samples of 190 species of 46 types of perennial plants stored stored in Forage perennial plant’s Genebank of Research Institute of Animal Husbandry, Mongolia, including more 100 samples of 7 species of Stipa. In recent time necessary to study the seed viability of Stipa species and increase, enrich and renew the seed resources in genebank. We studied the seed viability of needle grass (Stipa L) species, that are collected between 1994-2014from the territory of Mongolia. During the identification of lab germination the samples stored for 24 years did not germinated and 27.2% of samples stored for 20-22 years had only 0.4-8.0% of the germination. Whereas, the samples stored for 15-16 years are germinated in 24.0-96.0%, and samples stored for 4-9 years are 56.5-100.0%, and this results shown that the seed germination rate are depending from the stored years. During the field experiment the 11 samples of 3 species of Stipa were tested in irrigated areas and 13.6-72.7% of them were germinated, 50-100% of them survived to autumn and 83.3-100% of them survived for first winter. From our studies, the needle grass samples are quite good at surviving the winter-spring hardships and the vitality of the already-proven plant survival in the second year of life has increased.
 Хялгана (stipa l.)-ын төрлийн зарим зүйл ургамлын үрийн амьдрах чадвар
 Хураангуй: МААЭШХ-ийн Тэжээлийн олон наст ургамлын генофондод хадгалагдаж буй Хялгана (Stipa L) – ы төрлийн ургамлын үрийн амьдрах чадварыг судаллаа. Лабораторийн судалгааны явцад генофондод 24 жил хадгалагдсан дээжүүд огт соёолсонгүй, 20-22 жил хадгалагдсан дээжүүдийн 27.2% нь дөнгөж 0,4-8.0%-ийн соёололттой байлаа. Харин 15-16 жил хадгалагдсан дээжүүд 24.0-96.0%, 4-9 жил хадгалагдсан дээжүүд 56.5-100.0%-ийн соёололттой байгаагаас үзэхэд үрийн соёолох чадвар хадгалах хугацаанаас ихээхэн хамаарч (P≤0.001) байна. Хээрийн судалгаагаар Хялгана (Stipa L) – ы төрлийн 3 зүйлийн 11 дээжийг 2017 онд усалгаатай нөхцөлд тарьж туршихад 13.6-72.7%-ийн хээрийн соёололттой байсан бөгөөд амьдралын 2 дахь жилийн хавар 50-100% нь сэргэн ургаж, 83.3-100%-ийн амьдрах чадвартай байв. Бидний судалгаанаас Stipa -ийн төрлийн дээжүүд өвөл - хаврын хатуу ширүүн нөхцлийг даван туулж амьдралын эхний жилийн өвлийг давах чадвар нилээд сайн, амьдралын 2 дахь жилээс нэгэнт биежсэн ургамлын амьдрах чадвар нэмэгдэж байна.
 Түлхүүр үг: Генофонд, хээрийн соёололт, өвөлжилт, амьдрах чадвар

Characterizing species co-occurrence patterns of imperfectly detected stream fishes to inform species reintroduction efforts.

Species reintroduction efforts can improve the recovery of imperiled species, but successful implementation of this conservation strategy requires a thorough understanding of the abiotic and biotic factors influencing species viability. Species interactions are especially understudied, in particular by omitting the effect of imperfect detection on negative, neutral, or positive associations within a community. Using repeat surveys from 5 southern Ontario, Canada, Great Lakes tributaries, we quantified species co-occurrence patterns with the eastern sand darter (ESD) (Ammocrypta pellucida), listed as federally threatened, and characterized how imperfect detection during sampling can influence inference regarding these relationships. We used a probabilistic framework that included 3 approaches of increasing complexity: probabilistic co-occurrence analysis ignoring imperfect detection; single-species occupancy models with subsequent co-occurrence analysis; and 2-species occupancy models. We then used our occupancy models to predict suitable sites for potential future reintroduction efforts while considering the influence of negative species interactions. Based on the observed data, ESD showed several positive associations with co-occurring species; however, species associations differed when imperfect detection was considered. Specifically, a negative association between ESD and rosyface shiner (Notropis rubellus) was observed only after accounting for imperfect detection in the Grand River. Alternatively, positive associations in the Grand River between ESD and northern hogsucker (Hypentelium nigricans) and silver shiner (Notropis photogenis) were observed regardless of whether imperfect detection was accounted for. Our models predicted several potential reintroduction sites for ESD in formerly occupied watersheds with high levels of certainty. Overall, our results demonstrate the importance of investigating imperfect detection and species co-occurrence when planning reintroduction efforts.