Age Classes Research Articles

High-throughput sequence-based microsatellite genotyping for the non-model Neotropical tree species Anadenanthera colubrina (Leguminosae)

Background and aims – Anadenanthera colubrina is a Neotropical native forest tree species with significant ecological importance in Seasonally Dry Tropical Forests. Developing genetic markers for this species is relevant for conservation, breeding, and evolutionary studies. Previously available genetic markers for A. colubrina consisted of a few microsatellites. Next-generation sequencing (NGS) strategies allow simple and cost-effective development of new SSR loci from low-coverage whole genome shotgun sequencing. The main aim was to develop microsatellite markers for sequence-based high-throughput genotyping (SSRseq) in the species and to characterize their information content against traditional capillary electrophoresis-based microsatellite data by estimating the amount of molecularly accessible size homoplasy of each locus. Additionally, the reliability of these markers for population genetic analysis was assessed by genotyping two age classes (reproductively mature trees and seedlings) in a typical location in Argentina. Key results – Sixty primer pairs targeting microsatellites were designed, of which 25 were validated with allelic error rates < 3% and genotype missingness < 20%. A significantly higher number of alleles per locus and heterozygosity was detected for SSRseq considering sequence polymorphisms compared to analysing the same data based on sequence size (length) only. Size homoplasy, calculated as the proportion of mismatches between datasets relative to the number of alleles differing in length, averaged 97.85% over all SSR loci. High levels of population genetic diversity were detected in adults and seedlings from Paranaense forests, exceeding those reported in previous studies of A. colubrina using traditional SSRs. The generated datasets increase the resolution of capillary-based microsatellite genotyping, allowing for more accurate inference of eco-evolutionary processes in non-model tree species.

Roles of Spatial Distance, Habitat Difference, and Community Age on Plant Diversity Patterns of Fragmented Castanopsis orthacantha Franch. Forests in Central Yunnan, Southwest China

The semi-humid evergreen broadleaved forest (SEBF) is the zonal vegetation type of western subtropical regions in China. Under human and natural disturbance, the area of SEBFs is severely shrinking, with remaining fragments scattered across mountains of the Central Yunnan Plateau. To explore the mechanisms of community assembly and species maintenance in the severely fragmented SEBFs, we selected three sites—Jinguangsi Provincial Nature Reserve, Huafoshan Scenic Area, and Qiongzhusi Forest Park—across the range of this vegetation type, and sampled a total of 42 plots of forest dominated by Castanopsis orthacantha Franch., the most widely distributed community type of SEBFs. We compared the species richness and composition of the communities of different age classes, employed the net relatedness index to characterize the phylogenetic structure of communities, and used Mantel tests and partial Mantel tests to quantify the impacts of spatial distance, age class, and habitat factors (including climate, topography, and soil) on species turnover across different spatial scales (i.e., intra- and inter-site) for trees, shrubs, and herbs, respectively. The results indicated the following: (1) In the young stage, the C. orthacantha communities exhibited a species richness statistically lower than those in middle-aged and mature communities. Notably, the difference in species richness among age classes was merely significant for shrub and herb species. Moreover, the phylogenetic structure changed towards over-dispersion with increasing community age. (2) The age class of the community played a pivotal role in determining taxonomic β diversity in the tree layer, while climate and soil factors significantly influenced β diversity in the shrub and herb layers of the communities. (3) Environmental filtering emerged as the predominant force shaping community assembly at the intra-site scale, whereas spatial distance was the primary determinant at the inter-site scale. Meanwhile, dispersal limitation versus biological interaction seemed to dominate the community dynamics of the C. orthacantha communities in the early versus middle and old ages, respectively. Our results highlight the variability in community assembly processes across different spatial and temporal scales, providing insights into the priority of the conservation and restoration of severely degraded zonal SEBFs. Expanding research to broader scales and other SEBF types, as well as considering the impacts of climate change and human activities, would provide further insights into understanding the mechanisms of community assembly and effective conservation strategies.

Analysis of Wood Density to Compare the Amount of Accumulated Carbon Dioxide in the Stems of Selected Non-Native Tree Species in Poland

One of the priorities in European policy is the greater use of wood. In this context, it is important to know the total amount of CO2 absorbed by the tree and accumulated in the wood. In the timber industry, butt logs are mainly processed. The aim of this study is to analyze diameter at breast height (DBH), wood density (WD), and the amount of CO2 in grand fir (GF), Douglas fir (DF), northern red oak (NRO), and black locust (BL) wood. The DBH and bark thickness were measured, and cores were taken to study WD and calculate the amount of CO2. Analyses were conducted in three age classes of trees. It was found that in the youngest age class, DF had a significantly larger DBH compared to NRO and BL, and GF had a significantly larger DBH compared to NRO. The wood density of coniferous species was significantly lower compared to broadleaved species. DF absorbed the most CO2. In Class III, DF had significantly larger DBH and significantly lower wood density compared to NRO and BL. DF absorbed significantly more CO2 compared to NRO. In Classes IV and V, DF had larger DBH compared to NRO and lower wood density. The amount of CO2 absorbed by both species was similar. Taking into account the amount of absorbed CO2, the durability of the wood, and aspects related to sustainable forest management of the four studied non-native tree species, Douglas fir seems to be the best choice for cultivation in Polish forests.

Modeling Forest Regeneration Dynamics: Estimating Regeneration, Growth, and Mortality Rates in Lithuanian Forests

This study presents a novel approach to analyzing forest regeneration dynamics by integrating a Markov chain model with Multivariate Time Series (MTY) decomposition. The probabilistic tracking of age-class transitions was combined with the decomposition of regeneration rates into trend, seasonal, and irregular components, unlike traditional deterministic models, capturing the variability and uncertainties inherent in forest ecosystems, offering a more nuanced understanding of how Scots pine (Pinus sylvestris L.) and other tree species evolve under different management and climate scenarios. Using 20 years of empirical data from the Lithuanian National Forest Inventory, the study evaluates key growth and mortality parameters for Scots pine, Spruce (Picea abies), Birch (Betula pendula), and Aspen (Populus tremula). The model for Scots pine showed a 79.6% probability of advancing from the 1–10 age class to the 11–20 age class, with subsequent transitions of 82.9% and 84.1% for older age classes. The model for Birch shown a strong early growth rate, with an 84% chance of transitioning to the next age class, while the model for Aspen indicated strong slowdown after 31 years. The model indicated moderate early growth for Spruce with a high transition in later stages, highlighting its resilience in mature forest ecosystems. Sensitivity analysis revealed that while higher growth rates can prolong forest stand longevity, mortality rates above 0.33 severely compromise stand viability. The Hotelling T2 control chart identified critical deviations in forest dynamics, particularly in years 13 and 19, suggesting periods of environmental stress. The model offers actionable insights for sustainable forest management, emphasizing the importance of species-specific strategies, adaptive interventions, and the integration of climate change resilience into long-term forest planning.

Leaf Age Affects Mercury Accumulation in Evergreen Plants

We investigated the mercury (Hg) concentration of the full range of needle age classes (NACs) in two conifers, nine NACs in Picea abies and fourteen in Abies pinsapo var. marocana, as well as three leaf age classes (LACs) in two broadleaved evergreen species, Trochodendron aralioides and Rhododendron catawbiense. Additionally, the Hg concentration of the wooden branch segments to which the NACs were attached in the two conifers was studied. Picea abies showed a continued Hg accumulation over all NACs, but with an age-dependent decline in the accumulation rate. In Abies pinsapo var. marocana, maximum needle concentrations of Hg were reached after eight years. The concentration remained constant for NACs 9–14, indicating that needles had become saturated with Hg. The Hg concentrations of the branch segments were much lower than those of the needles in the older NACs. Over the three LACs of Trochodendron aralioides and Rhododendron catawbiense there was a steady increase in concentration with a weak indication of a declining Hg uptake rate in older leaves. The average needle/leaf lifetime Hg uptake rate per year was only half that of broadleaved species across all NACs and LACs. We conclude that in conifers maintaining a larger number of NACs there is a decline of the Hg accumulation rate in older NACs. In future biogeochemical research (empirical and modelling) and biomonitoring studies, the age of sampled leaves needs to be considered to account for the age dependence of leaf Hg concentration and accumulation rate.

Examination of Isotopic Signals to Determine Trophic Dynamics and Diet of Gulf of Maine Mysticetes Prior to an Oceanographic Regime Shift

Stable isotope analysis (SIA) is a useful tool to assess the health and foraging habits of large marine predators, metabolic stress, pregnancy, and migration patterns. This study provides baseline SIA data for four Gulf of Maine mysticete species and serves as a benchmark for future assessments. SIA was conducted on skin biopsies collected in two time periods: 1988 to 1992 (n = 15) and 1999 to 2005 (n = 187). Samples were collected from humpback whales (Megaptera novaeangliae; n = 116), fin whales (Balaenoptera physalus; n = 74), minke whales (Balaenoptera acutorostrata; n = 6), and North Atlantic right whales (Eubalaena glacialis; n = 6). There were statistically significant differences in isotopic value among species, years, and regions sampled. By species, North Atlantic right whale δ13C and δ15N levels were significantly different than the other species analyzed. Additionally, humpback whales had a δ15N value that was significantly higher than the value found in fin whales. By date, humpback whales showed significant difference in δ13C in 2002 from the two previous years. For fin whales, 2002 showed significant difference in δ13C for all other years’ samples (2000 to 2003). By region, two regions that were the greatest distance apart (Bay of Fundy and Great South Channel) showed significant differences in δ13C for humpback whales. Demographic analyses for humpback and fin whales found a significant difference between calves versus other age classes, presumably due to nursing. A decadal comparison of humpback whales at one site (Stellwagen Bank) found no significant difference between decades. This dataset provides a benchmark for stable isotope measurements in large baleen whales for this regional ecosystem.

The Tasmanian Estuary Perch Population—A Threatened Species?

Estuary perch (Percalates colonorum) are a long-lived and slow-growing species which are distributed throughout southeastern Australian estuaries. In Tasmania, only one known population remains which is located in the Arthur River, on the remote northwest coast. Tasmania is the only Australian state to list estuary perch as a wholly protected species (recreational and commercial), while other populations across their mainland distribution appear to be robust. A survey undertaken on estuary perch in the Arthur River in 2014–2015 indicated that the population was small (825–2375 fish) and dominated by three age classes between 12 and 14 years old. This population also has extremely low genetic diversity and is genetically distinct to mainland populations due to its geographic isolation. During a re-survey in December 2023, 378 estuary perch were captured, with 191 tagged and released, and 31 fish retained for age and gonad analysis. Although three strong age classes were detected (five, eight and twenty-three years), numerous weak and missing cohorts were apparent. This study also confirms this population has a delayed spawning season in comparison to mainland populations, with growth models and tag recaptures (32 fish) demonstrating a very slow but sexually dimorphic growth rate. By combining the datasets of the 2014/15 and 2023 survey, we present an updated understanding of the biology and population dynamics of this unique Tasmanian population, which has previously never been published. The results confirm the population is still reproductively active and stable; however, due to their restricted distribution, variable recruitment, slow growth, and small population, further conservation efforts are still required. Further legislative listings at both the state and federal levels are planned, which if successful will provide additional protection and assist in applications for external funding and resources. This will support the development of a recovery plan which will consider re-stocking efforts and re-establishment of previously inhabited waters and investigate potential actions to improve the genetics of the Tasmanian population. Additionally, educational campaigns to inform the public and recreational fishers on the status of estuary perch in Tasmania will be undertaken.

Sleep Preferences and Chronotype Traits Impact on Academic Performance Among University Students

Due to irregular daytime routines, chronotype changes, side jobs and exam periods after the COVID-19 pandemic, university students are trying to find new balances in their everyday life. The aim of the present study is to analyze the impact of daytime chronotype and hour preferences for the circadian rhythm on academic achievement among university students, considering their sleep habits and class frequencies in daytime and nighttime classes. Furthermore, this study aimed to analyze the differences in chronotype preferences with regard to age, sex, and academic schedule students are attending. A sample of 87 university second-year Psychology and Management students attending the academic year 2021/2022 after the governmental relief measures of the COVID-19 pandemic completed a 13-item questionnaire on sleep habits and preferences. Further variables encompassed sleep behaviors, such as age, sex, daytime and nighttime classes, as well as academic achievement. The results of the study showed that university students had a higher preference for the morningness type. Additionally, chronotype traits explained 30% (values from regression analysis) of academic achievement but did not directly impact academic results. The sleep-wake cycle diverged among age groups because the youngest participants (19–21 years old) and older participants (35–44 years old) reported higher academic scores during the first semester and the full academic year. No significant differences were identified with respect to sex. There is a lack of literature explaining the effect of sleep hours on academic achievement among students after stay-at-home rules during the COVID-19 pandemic. Thus, it is imperative to understand the difficulties students face with regard to their studying hours, working shifts, and daytime or nighttime classes to create a sustainable university system that attends to students’ needs and necessities.

Climate signal age effects in Pinus uncinata tree-ring density data from the Spanish Pyrenees

Key messageThe temperature sensitivity of maximum latewood density measurements in pine trees from a high-elevation site in the Spanish Pyrenees increases with tree age. Detrending modulates the intensity of the effect. Tree-rings are the prime archive for high-resolution climate information over the past two millennia. However, the accuracy of annually resolved reconstructions from tree-rings can be constrained by what is known as climate signal age effects (CSAE), encompassing changes in the sensitivity of tree growth to climate over their lifespans. Here, we evaluate CSAE in Pinus uncinata from an upper tree line site in the Spanish central Pyrenees, Lake Gerber, which became a key location for reconstructing western Mediterranean summer temperatures at annual resolution. We use tree-ring width (TRW) and maximum latewood density (MXD) measurements from 50 pine trees with individual ages ranging from 7 to 406 years. For MXD, temperature sensitivity increases significantly (p < 0.01) with tree age from r = 0.31 in juvenile rings with a cambial age < 100 years to r = 0.49 in adult rings > 100 years. Similar CSAE are not detected in TRW, likely affected by the overall lower temperature signal (rTRW = 0.45 vs. rMXD = 0.81 from 1951 to 2020). The severity of CSAE is influenced by the approach used to remove ontogenetic trends, highlighting the need to assess and consider potential biases during tree-ring standardization. Our findings reveal CSAE to add uncertainty in MXD-based climate reconstructions in the Mediterranean. We recommend studying CSAE by sampling diverse age classes in dendroclimatic field campaigns.

Demography and homing behavior in the poorly-known Philippine flat-headed frog Barbourula busuangensis (Anura: Bombinatoridae).

The flat-headed frog, Barbourula busuangensis, is a poorly known, riverine species, endemic to the province of Palawan in the Philippines. We applied capture-mark-recapture (CMR) methods to follow individuals at two sites (Malbato and San Rafael) in the island of Busuanga over 10 months in 2022-2023. We used passive internal transponders (PITs) to mark adult and subadults and single-colored visual internal elastomers (VIEs) for cohorts of juveniles. From a total of 196 frogs PIT-tagged in Malbato and 144 in San Rafael, we obtained overall recapture rates of 49% and 60% respectively. We used the POPAN formulation in MARK software to estimate abundance, survival, movement, and age-class demographics. Our best model estimated an average population size of 268 frogs at Malbato and 232 at San Rafael, and constant survival probabilities (mean ≥ 0.97) at both sites. When adding age classes to the model, abundance of adults was always higher than that of subadults producing an age structure dominated by adults at both sites. Growth rates decreased significantly with body size, being higher in juveniles (1.51 mm/month) and subadults (1.56 mm/month) than in adult frogs (0.60 mm/month). At these growth rates frogs may reach adulthood at 2.5 years, with the oldest individuals likely being over 11 years old. CMR data confirmed site fidelity, and translocation experiments revealed that frogs have the ability to home when displaced 10-50 m upstream and downstream from their original capture site. This is the first long-term study of B. busuangensis using robust field and analysis methods. Our data suggest that B. busuangensis is stable at present in Busuanga, with long-lived adults and dispersing subadults. We expect that these data may serve as baseline of current population abundance, age structure and growth rates which are factors that tend to be affected when species are threatened. In this way it may help researchers and conservation practitioners detect potential changes that may occur as this species confronts the challenges of the Anthropocene.

Citizen Science and Sea Turtles: Using iNaturalist as a Tool to Study Chelonian Conservation Biology

Sea turtles are among the most threatened group of marine animals, with all species at risk for an assortment of anthropogenic factors including pollution, over-fishing bycatch, and climate change. As the threats to these large aquatic reptiles continue to increase, populations may be facing declines in many areas of their native home ranges. Therefore, new techniques that allow for population monitoring alongside more traditional methods are needed to increase our understanding of these ocean-dwelling vertebrates. Due to their unique biology, sea turtles are often readily observed in near-shore waters and on beach habitats. I assessed the presence and general demography of sea turtles within the USA on the citizen science platform, iNaturalist and report on major findings related to mortalities, age classes, and states where observations are concentrated. iNaturalist observations in this publication represent 8,089 green, 1,171 loggerhead, 312 kemp&amp;rsquo;s ridley, 129 leatherback, 128 hawksbill, and 17 olive ridley sea turtles. Observations consisted primarily of adult age classes (85.9%), with moralities representing only 10.2%, and the majority of images showing beach habitat (55%) versus open water (44.8%). The number of observations increased annually indicating the potential for this citizen science application to provide valuable population trend data for conservation managers and future study of their nesting and behavioral biology worldwide.

Do the biological characteristics of trout (Salmo trutta) smolts influence their spring migration timing and maiden marine sojourn duration?

Anadromous salmonids migrate seaward to exploit feeding and growth opportunities in marine habitats, yet how smolt biological characteristics influence their marine migratory behavior remains poorly understood. This study used 9 years of trout (Salmo trutta) population monitoring data from 15,595 tagged age-0+ parr, 1033 smolts detected migrating downstream in spring, and 99 adults detected returning from their first marine migration to the River Frome (Dorset, UK) to investigate the influence of smolt biological characteristics on their migration timing and maiden marine sojourn duration. Age-specific differences in the influence of smolt length on migration timing were found, with longer 1-year-old smolts emigrating later than their shorter counterparts within the same age class, but the opposite association existed for 2-year-old smolts. A bespoke integrated statistical model quantified the effects of smolt emigration day of year, age, sex, and length on the probability of first-time migrants returning to the river after one or more sea winters. Younger, later migrating smolts had a longer marine sojourn duration than their older, earlier migrating counterparts, and females remained at sea for longer periods than males. Although the statistical model was designed to maximize the use of information available in the data, it revealed only weak effects of smolt biological characteristics on the maiden marine sojourn duration. A complementary simulation study suggested that detecting more spring migrating smolts and analyzing longer time series of trout population monitoring data would increase the ability to detect statistically significant effects. Therefore, a strategic review of the trout population monitoring program, including more long-term biological data collection, is recommended. The modelling work presented here can provide guidance on the size of the required dataset and how to maximize the power of imperfect data.

Chlamydial infections in free-ranging raptors presenting to a university veterinary medical teaching hospital (1993-2022).

To describe the prevalence, clinical findings, lesions, and risk factors associated with chlamydial infections in free-ranging raptors presented to a university veterinary medical teaching hospital. Medical records retrospectively searched for raptors admitted from January 1993 through April 2022 were tested for Chlamydia spp infections using quantitative PCR (qPCR), immunohistochemistry, culture, and sequencing. Findings were collected and analyzed. Multivariable logistic regression analyzed the association between Chlamydia spp infection status and risk factors, including age class, species, sex, and season of admission. The prevalence for cases that tested positive for Chlamydia spp on 1 or more diagnostic tests, including mucosal qPCR samples for Chlamydia spp, tissue PCR for C buteonis, and mucosal qPCR genotyped as C buteonis, was 1.9% (74 of 3,983). All positive cases were from the genus Buteo (n = 74). Juvenile birds and winter season had higher odds of infection. All birds were in poor body condition (n = 74), often with moderate-to-severe CBC and biochemistry abnormalities consistent with multiorgan chronic inflammatory disease, emaciation, and dehydration. On postmortem examination of Chlamydia-positive birds (58 of 74), hepatitis (44 of 56), nephritis (24 of 39), splenitis (22 of 53), airsacculitis (21 of 43), myocarditis (21 of 39), and pneumonia (21 of 38) were common lesions, with intracellular bacteria in multiple tissues. Signalment, season of admission, clinical signs, clinicopathologic findings, and Chlamydia-specific testing identified chlamydial infections in free-ranging raptors. Appropriate protections to prevent potential zoonotic transmission in clinical wildlife rehabilitation settings are recommended. Many clinical parameters used to identify C psittaci infection in parrots can also be used to identify chlamydial infections in raptors.

Aposematism vs. scavenging? camera trapping unveils low and seasonal-dependent consumption of toxic salamander carcasses by wild boars

Abstract Aposematic species rely on primary and secondary antipredator strategies. Yet, some opportunistic and generalist species may consume them, although this has been largely supported by indirect evidence such as dietary analyses or clay model experiments. Here, we studied the role of the wild boar, Sus scrofa, as a consumer and possible predator of an aposematic and toxic salamander, Salamandra salamandra gallaica. We investigated this behaviour using camera traps and salamander carcasses on a small island where both species co-occur. Our results show a very low proportion of salamanders consumed by wild boars (3.8%), which indicates that fire salamanders might not completely rely on their aposematic strategy to avoid being consumed by this generalist species. The number of predation events does not differ between wild boar age classes, but it does between seasons, with a higher consumption in spring, which can be associated with an increase in animal consumption when fruits (e.g., acorns) are no longer available on this island. We also highlight the need for temporal studies targeting predator-prey interactions through behavioural data and complementary approaches to better understand the possible impact of opportunistic and generalist species in the ecosystem. This is particularly important in management plans involving the control of generalist species such as the wild boar, which is considered one of the most invasive species globally and a threat to countless species worldwide.

The Use of Humor, Irony, and Metaphors in Everyday Communication: An Exploratory Investigation

This study explores the role of humor, irony, and metaphors in everyday communication among college students at Mindoro State University (MinSU). These rhetorical strategies are integral to social interactions, helping individuals convey emotions, form connections, and simplify complex ideas. Using an exploratory, qualitative approach, the researchers examined how selected students employ these techniques across various social contexts, including family, friends, and academic settings. Data collection involved in-depth interviews, allowing for analysis of sociolinguistic factors, such as age, gender, and social class, that influence humor, irony, and metaphors. The findings suggest that humor fosters camaraderie, while irony subtly critiques or expresses contradictions, and metaphors enhance comprehension by linking abstract ideas to familiar experiences. Cross-cultural insights reveal unique interpretations of these elements, manifesting the potential for misunderstandings in diverse settings. This research highlights the adaptive nature of these rhetorical tools, revealing how they bridge social gaps, reinforce group identity, and support communication. The study contributes to understanding language use in regional academic settings, offering implications for effective communication and cultural sensitivity in multicultural environments.

Have People Treated With Antihypertensives Been Diagnosed With Hypertension? A Cross-Sectional Study in Stockholm, Sweden.

Studies on antihypertensive treatment are important, as hypertension remains the major risk factor for cardiovascular morbidity and premature death. However, antihypertensive medicines are also used for other conditions, and the use of these medicines as a proxy for a diagnosis of hypertension might lead to misclassification in pharmacoepidemiological studies. This study aimed to investigate to what extent people dispensed antihypertensive medicines have been diagnosed with hypertension. Cross-sectional study with data covering all healthcare and all dispensed prescriptions of antihypertensive medicines 2019 and diagnoses recorded 2015-2019 from the Stockholm Region, Sweden. Multinomial logistic regressions were used to assess the probability of having hypertension concerning age, sex, and antihypertensive drug class. A total of 386 860 individuals were included, 49% men, 12% incident users, and 80% of all had a recorded diagnosis of hypertension. In 73% of incident users, only one antihypertensive drug class was dispensed, as compared to 36% of prevalent users. A total of 38% of incident users and 9% of prevalent users had none of the diagnoses selected for the study recorded in any health record during 5 years. Prevalent and older users over the age of 65 from high (50%-79%) to very high (80% and more) probability of a recorded diagnosis of hypertension. Patients on antiadrenergic agents, high-ceiling diuretics, aldosterone antagonists, or beta receptor blockers had a lower probability of having a recorded diagnosis of hypertension than patients dispensed angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, or calcium channel blockers. Most patients dispensed antihypertensive medicines have a diagnosis of hypertension. However, caution is needed using data on dispensed medicines to classify incident antihypertensive users and younger patients as having a diagnosis of hypertension.

Packed Cell Volume and Plasma Chemistry Reference Intervals for Eurasian Eagle Owls (Bubo bubo) in a Rehabilitation Setting in South Korea before Release.

Rehabilitation and release of wild birds hinge upon a comprehensive understanding of both biologic and nonbiologic factors, including the medical and physical fitness of the animal. The objectives of this study were to determine reference intervals of packed cell volume and plasma chemistry values for healthy Eurasian Eagle Owls (Bubo bubo) and to compare blood values between age and sex classes. There were significant differences between males and females in total protein and globulin mean values, with males having higher values than females. Adult and juvenile Eagle Owls differed significantly in the mean values of calcium, alkaline phosphatase, and uric acid, with juveniles having higher values than adults. The calculated reference intervals for Eagle Owls can be used in Eurasian Eagle Owls admitted to rescue centers to assist veterinarians and wildlife managers to clinically evaluate and monitor the health of Eagle Owls and make decisions about when to release them after treatment.

STUDENTS HELPING OLLI BUILD A MORE DIVERSE MEMBERSHIP WITH AN ASSESSMENT OF AVAILABLE TRANSPORTATION OPTIONS

Abstract An undergraduate adulthood and aging class partnered with Osher Lifelong Learning Institute’s (OLLI) Diversity Committee to identify transportation resources available for seniors in their community to potentially increase the diversity of the OLLI membership. A needs assessment research framework was used to put a semester long, four-phase research project into place, each with specific goals and milestones. General milestones included researching available transportation resources and organizations for seniors; documenting target audiences and associated difficulties using said resources; exploring potential solutions and providing recommendations for future pilot projects. The Director of the OLLI program attended monthly report outs to assist in the creation of a doable pilot project, helping identify key constraints and logistics. The semester ended with a formal research report out, executive summary, and the university career counselor attending to help students brainstorm and create solid resume entries. The presentation will finish by describing what was learned via best practices and practices to avoid, particularly intergenerational “gaps” that surfaced on how to collect research, the types of research, and the breadth and depth of the research. Lastly lessons learned as a teacher on how to be in the “middle” of both generations and the OLLI director to help make the project a success and how to get student “buy in” by continually reviewing the importance of participating in a service-learning class project for future career aspirations.

Interspecific competition and survival pressures in endangered Barringtoniaracemosa populations of Mainland China

This study evaluates the growth, survival pressures, and community dynamics of Barringtonia racemosa (L.) Spreng. populations in Jiulong Mountain and Suixi County, Guangdong Province. Six distinct plant communities were identified, with human disturbances significantly disrupting natural succession processes. The population in Jiulong Mountain, particularly within the Talipariti tiliaceum-B. racemosa community (JLS-T), experienced higher survival pressures compared to Suixi County. Interspecific competition varied, with species like Derris trifoliata, T. tiliaceum, and invasives such as Ipomoea cairica and Mikania micrantha exerting substantial pressure on B. racemosa. Analysis of 234 B. racemosa individuals revealed significant correlations between diameter at breast height (DBH), plant height, and age structure distribution, with a linear relationship between DBH and height underscoring their relevance in understanding wood volume, biomass, and stand structure. Survival pressures were inversely related to DBH, indicating reduced competition as trees matured. Growth patterns exhibited an age-dependent plateau in height, potentially influenced by environmental and anthropogenic factors. Management strategies should prioritize the growth of individuals with DBH less than 5 cm (age classes I ~ II). These findings underscore the need for targeted conservation efforts to protect B. racemosa communities and sustain wetland ecosystems.

Climatic and edaphic influences on productivity and carbon sequestration of farm grown teak (Tectona grandis, linn.f) in Tamil Nadu, India

Teak (Tectona grandis, Linn.f) is one of the most sought-after tree crops due to the exceptional quality and high market value of its timber. Currently, the Indian subcontinent imports a significant quantity of teak to meet its growing demand. The growth and wood quality of teak are influenced by edaphic and climatic variations across sites, a factor that has been largely underexplored in research. The primary objective of the study is to analyse teak growth, wood quality, and carbon sequestration potential under farmland condition. To address this, the study was conducted across three agroclimatic zones of Tamil Nadu: North Eastern Zone (NEZ), North Western Zone (NWZ), and Cauvery Delta Zone (CDZ), focusing specifically on farmland conditions. The analysis encompassed biometric attributes, volume, and carbon sequestration potential of farm-grown teak across different age classes. The findings of the study reveal that among the three agroclimatic zones, the NEZ (15-20 years age class) recorded the highest biometric attributes, including mid diameter (MD) (0.193 m), volume (0.379 m3), heartwood proportion (0.239 m3), and carbon sequestration (0.683 Mg/acre).. Based on the overall performance, trees in the 15-20 years age class exhibited superior heartwood formation under farmland conditions. Therefore, this age class is recommended for teak cultivation in farmland conditions across Tamil Nadu to maximize growth, wood quality, and carbon sequestration potential.