Start Of Season Research Articles

Projections of the start of the airborne pollen season in Barcelona (NE Iberian Peninsula) over the 21st century

The effects of global warming are numerous and recent studies reveal that they can affect the timing of pollination. Temperature is the meteorological variable that presents a clearer relationship with the start of the pollination season of most of the observed airborne pollen taxa. In Catalonia, in the last fifty years, the average annual air temperature has increased by +0.23 °C/decade, and the local warming has been slightly higher than the one on a global scale. Projections point to an increase in temperature in the coming decades, which would be more marked towards the middle of the century.To analyse the effect of the increase in temperature due to global warming on the starting date of pollen season in Barcelona, a forecasting model has been applied to a set of projected future temperatures estimated by the European RESCCUE project. This model, largely used in the literature, is based on determining the thermal needs of the plant for the pollen season to begin. The model calibration to obtain the initial parameters has been made by using 20 years of pollen data (2000–2019), and the model effectiveness has subsequently been tested through an internal evaluation over the period of the calibration and an external evaluation on 4 years not included in the calibration (2020−2023). The mean bias error in the internal calibration ranged between −0.4 and − 0.6 days, and between +0.5 and − 8.3 in the external one, depending on the taxon. The results of the application of the model to the temperature projections over the 21st century point to a progressive advancement in the pollination dates of several pollen types abundant in the city, allergenic most of them. These advances ranged, at the end of the century, between 15 and 27 days, depending on the climate model, for the scenario of the highest concentrations (RCP8.5) and between 7 and 12 days for the emissions stabilization scenario (RCP4.5).

Mapping and predicting cassava mosaic disease outbreaks using earth observation and meteorological data-driven approaches

Cassava Mosaic Disease (CMD) poses a significant threat to cassava (Manihot esculenta Crantz) production, both globally and in Thailand. Caused by the Cassava Mosaic Begomovirus (CMB), CMD conventional detection methods involve field-based visual assessment and mapping, which can be time-consuming and labour-intensive.In this study, field-based surveys have been conducted during the early wet season cassava planting period in three different productive regions of Thailand. Five classification models (namely ANN, RF, XGBoost, SVM, and Ensemble learning) were employed to predict CMD occurrence with various sets of optimized predictive meteorological and remote sensing features. Field based CMD observations have been used for modelling validation and accuracy assessment.Utilizing time series of Sentinel-2 MSI Level-2A images, we estimate cassava start of season (SOS) across both before and after planting periods on a gridded basis. Establishing meteorological and remote sensing time frames, we aggregate predictive features through different temporal windows. Employing interactive and multistage correlation analysis, along with feature importance ranking, we optimize the selection of predictive features, effectively reducing multicollinearity. The Ensemble model and the usage of combined meteorological and remote sensing optimized predictive features showed best prediction results achieving an overall accuracy of 90%, F1-score of 0.90, Matthews Correlation Coefficient of 0.71, unit-normalized MCC* of 0.85, and an average central actual accuracy of approximately 0.85.Observed CMD patterns demonstrate that soil-crop suitability and farming practices (including the use of most CMD susceptible cultivars) significantly influence the CMD spread in selected farming areas. However, modelling analysis revealed that, among several meteorological features, CMD occurrence is associated with predominant winds blowing across the entire before and after planting periods, mainly from the first quadrant, and to a lesser extent, humidity. Notably, higher disease incidence areas corresponded with SOS events in January and February. In predicting CMD, individual S2-MSI bands were not crucial, but NDVI and EVI emerged as the most explanatory remote sensing features, followed by GNDVI and PSRI indices.The study's findings highlight that coupling CMD occurrence modelling, combined remote sensing and meteorological data with conventional field-based observations may significantly enhance targeted disease management protocols and assessing potential impacts on cassava yields.

Identification of parameters that affect the conception rate of precocious Nelore heifers before the start of the breeding season

Identification of parameters that affect the conception rate of precocious Nelore heifers before the start of the breeding season

Assessing wild turkey productivity before and after a 14-day delay in the start date of the spring hunting season in Tennessee.

Ten state wildlife management agencies in the United States, including six within the Southeast, have delayed their spring wild turkey (Meleagris gallopavo) hunting seasons since 2017 by five or more days to address concerns related to the potential effects of hunting on wild turkey seasonal productivity. One hypothesis posits that if the spring hunting season is too early, there may be insufficient time for males to breed hens before being harvested, thus leading to reduced seasonal productivity. We conducted an experiment to determine whether delaying the wild turkey hunting season by 2 weeks in south-middle Tennessee would affect various reproductive rates. In 2021 and 2022, the Tennessee Fish and Wildlife Commission experimentally delayed the spring hunting season to open 14 days later than the traditional date (the Saturday closest to 1 April) in Giles, Lawrence, and Wayne counties. We monitored reproductive rates from 2017 to 2022 in these three counties as well as two adjacent counties, Bedford and Maury, that were not delayed. We used a Before-After-Control-Impact design to analyze the proportion of hens nesting, clutch size, hatchability, nest success, poult survival and hen survival with linear mixed-effect models and AIC model selection to detect relationships between the 14-day delay and reproductive parameters. We detected no relationship (p > .05) between the 14-day delay and any individual reproductive parameter. In addition, recruitment (hen poults per hen that survived until the next breeding season) was very low (<0.5) and did not increase because of the 14-day delay. The traditional Tennessee start date had been in place since 1986 while the turkey harvest increased markedly until about 2006 and more recently stabilized. Our data indicate that moving the start of the hunting season from a period just prior to peak nest initiation to 2 weeks later, to coincide with a period just prior to peak nest incubation initiation, resulted in no change to productivity or populations in wild turkey flocks in south-middle Tennessee.

Temporal dynamics of the egg bank of Aedes aegypti (Diptera: Culicidae) in the winter-spring transition in a temperate region.

In temperate regions, the populations of Aedes aegypti (L.) (Diptera: Culicidae) remain in the egg stage during the winter. In Buenos Aires, Argentina, a temperate region in the southern limit of Ae. aegypti distribution, the start of the next reproductive season and the rate of increase of the adult population depend on the egg bank that remains after the winter. This study aimed to analyze the mortality, field-hatching, and survival of eggs exposed to field conditions representative of those that occur in nature. In addition, the post-exposure hatching response of the eggs was assessed. Four egg batches were exposed to natural conditions starting in mid-winter and were recovered progressively after 3, 6, 9, and 12 weeks. One egg batch (initial control) was not exposed in the field and remained under laboratory conditions. After the exposure period, the recovered intact, collapsed, and hatched eggs were counted. Intact eggs were immersed three times in the laboratory to study their hatching response. Progressive increases in the proportion of lost (presumably by predation), dead, and hatched eggs in successive egg batches were recorded. Field-hatching was recorded from late winter onwards. The first hatchings occurred in conditions probably not favorable to complete development into reproductive adults. A progressive decrease in live eggs was observed, with 51% of the recovered eggs alive after 12 weeks of exposure. In the laboratory, the hatching response in the first immersion was low for the initial control and for the eggs exposed for 3 weeks, and increased for successive cohorts. The results confirm that the survival of Ae. aegypti eggs in the winter-spring transition ensures persistence throughout the next favorable season in Buenos Aires City. The observed inhibition to hatch of the first batches might relate to a photoperiod-induced diapause, as observed in previous studies.

The Influence of Climate Variability and Future Climate Change on Atlantic Hurricane Season Length

AbstractAtlantic hurricane season length is important for emergency management preparation, motivating the need to understand its variability and change. We investigated the influence of ocean variability on Atlantic hurricane season length in observations and a future climate simulated by the Energy Exascale Earth System Model (E3SM). We found that multiple factors influence hurricane season length, through their influence on season start and end. Warm western subtropical Atlantic sea‐surface temperature anomalies (SSTAs) during boreal spring (before the official hurricane season start) drive early starts to the hurricane season, and vice versa for cool SSTAs. Meanwhile, La Niña in autumn (before the official hurricane season end) drives late ends to the hurricane season, and vice versa for El Niño. E3SM projects a 27‐day increase in future Atlantic hurricane season length given La Niña and warm northern tropical Atlantic SSTAs. This research documents sources of predictability for Atlantic hurricane season length.

The impact of temperature on increased airborne pollen and earlier onset of the pollen season in Trentino, Northern Italy

The impact of climate change on ecosystems can be assessed through pollen dispersion data, which acts as a proxy for the plant flowering stage. The aim of this study is to verify if changes occurred in the season and concentration of airborne pollen in Trentino (Northern Italy), and to evaluate if temperature (T), precipitation (P), and/or land use influenced such changes in the period 1989–2018. Airborne pollen, sampled by a Hirst-type trap, was analyzed by light microscopy, and pollen concentrations were obtained. Twenty-four taxa, covering 95% of the local pollen spectrum, were considered for this study. A significant upward trend in annual pollen integral (APIn) is the main outcome over the study period. The increase in APIn is more evident when analyzing the data in three decadic blocks, both for all the considered taxa (+ 58%) and for Arboreal Pollen (AP; + 155%). Considering both the annual data and the decadic blocks, APIn shows a significant positive trend for Cupressaceae/Taxaceae, Ulmus, Populus, Salix, Ostrya, Quercus, Olea (AP), and Plantago, Cannabaceae, Ambrosia (non-arboreal pollen, NAP); a significantly earlier start of the Main Pollen Season (MPS) is proved for Rumex and Poaceae. APIn for 24 taxa shows a significant positive correlation with annual T min (< 0.005) and T mean (< 0.001), both of which showing a significant increase, and a negative correlation (< 0.025) with the number of frost days. From a human health perspective, higher temperatures, driven by climate changes, lead to higher concentrations of allergenic airborne pollen, turning into a higher risk for allergy sufferers.

Modelling antecedent soil hydrological conditions to improve the prediction of landslide susceptibility in typhoon-prone regions

Most regional landslide susceptibility models do not consider the evolving soil hydrological conditions leading up to a multiple occurrence regional landslide event. This results in inaccurate predictions due to the non-linear behaviour of the terrain. To address this, we have developed a simple and efficient model that incorporates the mid-term evolution of soil hydrological conditions. The model combines a water balance model and a geotechnical model based on infinite slope theory. The analysis of 561 high-intensity rainfall events in a typhoon-prone region of the Philippines revealed that the percolation of water during the 5-month wet season is crucial in determining landslide susceptibility. Consequently, high-intensity rainfall events at the start of the wet season are less likely to trigger landslides, while later events are more hazardous. We analysed the change in landslide susceptibility during the 2018 rainy season by comparing the probability of failure (PoF) before and after three high-intensity rainfall events (July, August and September). Only the event in September caused a significant increase in the probability of failure (PoF). The model showed an accuracy of 0.63, with stable cells better represented than unstable cells. The antecedent hydrological conditions on the lower soil layers are responsible for changes in landslide susceptibility. Our findings support the hypothesis that new approaches to developing hydro-meteorological thresholds for landslide early warning systems should be evaluated, especially in regions with strong seasonality.

Breeding parameters of a Great Tit (Parus major) population on the island of Cyprus compared to other Mediterranean populations

Many studies on the Great Tit, Parus major, have been conducted within the Mediterranean Basin, especially on its reproductive biology, forest habitat interactions, and nutritional resources. However, to date no detailed scientific research on these issues has been conducted on the island of Cyprus with a general paucity in research on this topic from the Eastern Mediterranean. Island species, through reduced gene flow and general isolation often evolve reproductive differences from their mainland relatives. As Cyprus is the third largest island in the Mediterranean and the most easterly positioned it provides an ideal opportunity compare the breeding biology of this island population with those from the wider Mediterranean region. This study aimed to gather some baseline reproductive data for Great Tits breeding in Cyprus. This data was then used to compare the reproductive outputs of Cypriot Great Tits from the sub species Parus major aphrodite with other Mediterranean island populations. This study was performed over a 3-year period during the breeding seasons of 2016-2018 in four evergreen forest areas. Mean clutch size was 7.7 eggs and hatching success 76.0%. The mean weight of the young was 16.3 g and mean tarsus length 18.7 mm. Significant differences were found between the years of the study, both in mean clutch size (p<0.0001) and the day of the first egg (p<0.0001), with 2016 producing the largest clutches and clutches being laid earlier than the subsequent two years. The start of the breeding season of the Great Tit was considerably earlier in Cyprus compared to other Mediterranean regions.

Co-influence of the start of thermal growing season and precipitation on vegetation spring green-up on the Tibetan Plateau

The climate in the Tibetan Plateau (TP) has undergone significant change in recent decades, mainly in thermal and water conditions, which plays a crucial role in phenological changes in vegetation spring phenology. However, how the start of the thermal growing season (SOS-T) and the start of the rainy season (SORS) as key climatic factors affect vegetation green-up remains unclear. Given that these factors characterize thermal and water conditions required for vegetation green-up, this study investigated changes in the SOS-T and SORS from 1961 to 2022, using observation-based datasets with long time series. We found that the SOS-T and SORS have advanced across the TP in 1961–2022 and have shown a spatial pattern of advancement in the east and delay in the west in 2000–2022. Further, the co-effect of temperature and precipitation change on the start of vegetation growing season (SOS-V) in 2000–2022 was observed. Averaged across TP, the SOS-V had an early onset of 1.3 d per decade during 2000–2022, corresponding to advanced SOS-T and SORS. Regionally, the SOS-V generally occurred nearly at the same time as the SOS-T in the high-altitude meadow region. A substantial delay in the SOS-V relative to the SOS-T was observed in the desert, shrub, grassland and forest regions and generally kept pace with the SORS. Furthermore, for 50% of the vegetated regions on the TP, inter-annual variation in the delay in the SOS-V relative to the SOS-T was dominated by precipitation change, which was profound in warm-climate regions. This study highlights the co-regulation of precipitation and temperature change in the SOS-V in different vegetation cover regions in the TP, offering a scientific foundation for comprehending the impact of climate change and prospects for vegetation phenology on the TP.

Classification of postpartum beef cows as estrous cycling or anestrous through the use of estrus detection patches prior to the start of the breeding season

Classification of postpartum beef cows as estrous cycling or anestrous through the use of estrus detection patches prior to the start of the breeding season

Herbal leys increase forage macro- and micronutrient content, spring lamb nutrition, liveweight gain, and reduce gastrointestinal parasites compared to a grass-clover ley

Commercial herbal leys (multispecies swards) are rapidly gaining popularity due to their potential to deliver an enhanced suite of ecosystem services. However, little is known about their impact on lamb production. A 2-ha split-field experiment using an herbal and grass-clover ley (0.33 ha paddock−1, n = 3 per sward) aimed to evaluate the effect of sward-type on forage quality and lamb productivity. Lambs (n = 40 per sward) were rotationally grazed over two experimental seasons: autumn 2020 (males) and spring 2021 (females). Sward quality was measured at the start of each grazing season. Liveweight gain and faecal egg counts (FEC) were measured at week 0, 4 and 6 in autumn and week 0, 4, 9 and 11 in spring. Blood samples were analysed after 11-weeks in spring to assess mineral status. General sward nutritional quality (e.g., crude protein) did not improve under the herbal ley, however, higher sward macro- and micronutrient concentrations were observed in both seasons. Spring liveweight gain was significantly greater in lambs grazing the herbal (172 ± 7 g d−1) vs. grass-clover ley (144 ± 7 g d−1), while autumn liveweight gain showed no difference. Spring lambs grazing the herbal ley compared to the grass-clover ley had elevated plasma cobalt (2.0 ± 0.1 nmol l−1vs. 1.6 ± 0.1 nmol l−1) and selenium (0.7 ± 0.04 µmol l−1vs. 0.5 ± 0.01 µmol l−1), with lower blood urea (7.7 ± 0.3 nmol l−1vs. 10.4 ± 0.4 nmol l−1). Spring FEC scores were reduced by 78 % in herbal grazed lambs; there were no significant differences in autumn FEC from either sward. In conclusion, the herbal ley resulted in seasonal improvements in sward micronutrient content and lamb parasite burden, mineral status, and productivity.

Shift from income breeding to capital breeding with latitude in the invasive Asian shore crab Hemigrapsus sanguineus

Organisms vary in the timing of energy acquisition and use for reproduction. Thus, breeding strategies exist on a continuum, from capital breeding to income breeding. Capital breeders acquire and store energy for breeding before the start of the reproductive season, while income breeders finance reproduction using energy acquired during the reproductive season. Latitude and its associated environmental drivers are expected to heavily influence breeding strategy, potentially leading to latitudinal variation in breeding strategies within a single species. We examined the breeding strategy of the Asian shore crab Hemigrapsus sanguineus at five sites spanning nearly 10° of latitude across its invaded United States range. We hypothesized that the primary breeding strategy of this species would shift from income breeding to capital breeding as latitude increases. We found that though this species’ breeding strategy is dominated by capital breeding throughout much of the range, income breeding increases in importance at lower latitudes. This latitudinal pattern is likely heavily influenced by the duration of the foraging and breeding seasons, which also vary with latitude. We also found that reproductive characteristics at the northern and southern edges of the invaded range were consistent with continued range expansion. We suggest that the reproductive flexibility of the Asian shore crab is a key facilitator of its continued invasion success. Our results highlight the influence of latitude on the breeding strategy of a species and emphasize the need for further research regarding the ecological importance and implications of flexibility in breeding strategies within species.

Species-Level Classification of Peatland Vegetation Using Ultra-High-Resolution UAV Imagery

Peatland restoration projects are being employed worldwide as a form of climate change mitigation due to their potential for long-term carbon sequestration. Monitoring these environments (e.g., cover of keystone species) is therefore essential to evaluate success. However, existing studies have rarely examined peatland vegetation at fine scales due to its strong spatial heterogeneity and seasonal canopy development. The present study collected centimetre-scale multispectral Uncrewed Aerial Vehicle (UAV) imagery with a Parrot Sequoia camera (2.8 cm resolution; Parrot Drones SAS, Paris, France) in a temperate peatland over a complete growing season. Supervised classification algorithms were used to map the vegetation at the single-species level, and the Maximum Likelihood classifier was found to perform best at the site level (69% overall accuracy). The classification accuracy increased with the spatial resolution of the input data, and a large reduction in accuracy was observed when employing imagery of &gt;11 cm resolution. Finally, the most accurate classifications were produced using imagery collected during the peak (July–August) or early growing season (start of May). These findings suggest that despite the strong heterogeneity of peatlands, these environments can be mapped at the species level using UAVs. Such an approach would benefit studies estimating peatland carbon emissions or using the cover of keystone species to evaluate restoration projects.

Impacts of Climate Change Scenarios on the Corn and Soybean Double-Cropping System in Brazil

Brazil is one of the main producing and exporting countries of corn and soybean and a continental country with climatic diversity that allows the cultivation of these crops in various agricultural systems. Double cropping is a widely adopted system throughout the national territory, where it is possible to cultivate soybeans at the beginning of the growing season, followed by corn in succession, in the same growing season. The present study aims to systematize the scientific knowledge about the impacts of future climate change scenarios on yield and on the double-cropping system of soybean + corn in Brazil. Systematic review procedures were adopted. The soybean yield is projected to increase in all regions of Brazil under all climate scenarios. Corn yields under future climate scenarios are projected to decline, with the subtropical climate region being less affected than the northern regions. The double-cropping systems of soybean + corn tend to present increasing climate risks in tropical climate regions. Climate change scenarios point to a delay in the start of the rainy season that will delay the sowing of soybeans, consequently delaying the sowing of corn in succession, resulting in fewer rainy days to complete its cycle.

134 A 12-year summary of effects of body weight at breeding and synchronization protocols on reproductive success of Bos indicus-influenced beef heifers grazing warm-season grasses

Abstract A retrospective analysis of 5 studies (2011 to 2022) evaluated the effects of body weight and synchronization protocols before the start of breeding season on reproduction of Bos indicus-influenced beef heifers. Data were collected from 594 Brangus crossbred heifers weaned on average at 280 ± 26 d of age, allocated to bahiagrass pastures (4 to 5 heifers and 0.8 to 1.0 ha/pasture), and supplemented with soybean hulls-based concentrate (0.5 to 1.8% of body weight, (BW); dry matter basis] from 2 weeks post-weaning until the end of the breeding season (189 ± 24 days of supplementation). Heifers were initially sorted into those that were supplement (S) and were not supplemented (NS) assigned to an estrous synchronization protocol before the start of the breeding season. Then, within each synchronization group, heifers were sorted into those that were below (BE) or above (AB) the average BW of all heifers (300 kg) at the start of the breeding season (n = 130, 126, 146, and 192 for BE+NS, BE+S, AB+NS, and AB+S heifers, respectively). Data were analyzed using GLIMMIX procedure of SAS using synchronization, BW at breeding, and resulting interaction as fixed effects, and heifer (synchronization × BW), study, and pasture(study) as random effects. Effects of synchronization × BW at breeding and synchronization were not detected for heifer BW and overall average daily gain (ADG). However, AB heifers were always (P &amp;lt; 0.0001) heavier from post-weaning until the end of the breeding season and had (P &amp;lt; 0.0001) greater overall ADG than BE heifers. Effects of synchronization × BW at breeding tended (P = 0.07) to detected for puberty attainment at the start of the breeding season, which was least (P &amp;lt; 0.01) for BE+NS, did not differ between BE+S vs. AB+NS (P = 0.37), and was greatest for AB+S heifers (31, 66, 60, and 81 ± 7.4%, respectively). However, final pregnancy and calving percentages differed (P &amp;lt; 0.01) only for BE vs. AB heifers (68 vs. 81 ± 4.4% and 63 vs. 75 ± 5.2%, respectively). Effects of synchronization × BW at breeding tended (P = 0.10) to detected for percent of heifers calving within the first 30 days of the calving season, which was least (P &amp;lt; 0.03) for BE+NS and did not differ (P = 0.20) among BE+S, AB+NS, and AB+S heifers (48, 69, 61, and 64 ± 5.9%, respectively). Hence, in Bos indicus-influenced beef heifers, BW above 300 kg at the start of the breeding season led to improved overall reproductive performance compared to BW &amp;lt; 300 kg, whereas estrous synchronization protocols had positive effects to puberty attainment (regardless of heifer BW) and improved early calving distribution only when heifers were below 300 kg at the start of the breeding season.

Ten daily rainfall forecasting using SSA algorithms and Seasonal ARIMA model to determine the beginning of the rainy season

Rainfall is one of the most important hydrological parameters. Based on the prediction of rainfall, several plans related to rainfall can be carried out, including predicting the start of the planting season based on information on the beginning of the rainy season and preparing cropping patterns. The purpose of this study is to predict the ten daily rainfall for 12 months from January to December of the following year and predict the start of the rainy season based on BMKG criteria. Modeling and forecasting is carried out on the ten daily regional rainfall in the catchment of Citarum-Majalaya water gauge using the Singular Spectrum Analysis (SSA) algorithm and the Seasonal ARIMA model. Forecasting model performance is measured using error values, namely mean absolute percentage error (MAPE). The results of these performance tests illustrate that the SSA algorithm and the Seasonal ARIMA model have fairly good accuracy for predicting rainfall for the next 6 months, where each has a MAPE value of 36.8 percent and 40.0 percent. Prediction of the beginning of the rainy season at the study location based on SSA forecasting results is most likely to occur on the 3rd of October, in accordance with BMKG predictions. whereas based on the results of the SARIMA forecasting model, the beginning of the rainy season is likely to occur on the 1st of November, and another possibility that the beginning of the rainy season will occur on the 2nd of October.

The allergenic potential of green urban areas in the Macaronesian islands: The case of Funchal City (Madeira)

Public gardens are elements that constitute the urban green infrastructure. Such units provide ecosystem services that are becoming a key concern in urban planning strategies.In this survey the allergenic potential of two public gardens in Funchal, a city exhibiting sub-tropical and Mediterranean climatic features, was assessed. Different allergenic risk scenarios were considered, and the Allergenicity Indexes recalculated. Results show that the Municipal Garden exhibits an IUGZA (Index of Urban Green Zone Allergenicity) of 0,39 and Santa Catarina Park an IUGZA of 0,16, which are considered spaces of moderate and low allergenicity level, respectively. Among the tested scenarios that could aggravate the IUGZA values, the worst would be an extension of the pollen season for all species. This might represent an issue considering the overall trend towards an earlier start and later end of the pollen season from important allergenic plants in Europe. The assessment of the IUGZA should include all plant biotypes of an urban green area in subtropical regions as they allow us to infer more precisely on the real risk population is exposed to. It seems that increasing species diversity can improve the allergenic indexes, but novel invasive species should be studied to assess their allergenicity level.

Precipitation explains Wood Thrush (Hylocichla mustelina) occupancy patterns in Northern Costa Rica

Introduction: The Wood Thrush is a migratory bird that has experienced dramatic declines in its populations in recent decades. This species overwinters in forest fragments with intermediate levels of habitat modification in Central America. However, more studies detailing the use of remnant forests through time are needed to elucidate the threats this species faces in the wintering grounds. Objective: To understand the effects of environmental and forest structure variables on the occupancy of Wood Thrush in Northern Costa Rica. Methods: The study area was the Área de Conservación Guanacaste (ACG), located in Northern Costa Rica, in December 2016, and during the 2018-2019 migration season. We estimated Wood Thrush occupancy and detection probability in four locations of ACG (dry forest, cloud forest, and two locations in the wet forest) using single-season occupancy models. We also estimated Wood Thrush occupancy and probability of persistence in different months in three vegetation types (open area, secondary forest, and old-growth forest) in the wet forest of ACG using a multi-season occupancy model approach. Results: Wood Thrush occupancy was best described by precipitation in the four locations of the ACG; the probability of occupancy increased with precipitation. The average occupancy of Wood Thrushes varied with vegetation type: open area with shrubs and forest edge (0.69 ± 0.09), secondary forest (0.46 ± 0.1), and old-growth forest (0.61 ± 0.1). Wood Thrush probability of persistence responded partially to changes in precipitation, with an unexpected increase in persistence when the rainfall continued decreasing in the season. Conclusion: Wood Thrush occupancy was best predicted by changes in precipitation considering a larger spatial scale. Its probability of persistence partially varied with precipitation. An increase in persistence closer to Spring migration might be explained by the start of the breeding season of resident birds, potentially reducing territorial conflicts and conserving energy before migration. The long-term protection of wet forests in Northern Costa Rica is of paramount importance for the conservation of Wood Thrushes in their wintering grounds.

Observations of Respiratory Syncytial Virus (RSV) Nucleic Acids in Wastewater Solids Across the United States in the 2022-2023 Season: Relationships with RSV Infection Positivity and Hospitalization Rates.

Respiratory syncytial virus (RSV) is a leading cause of respiratory illness and hospitalization, but clinical surveillance detects only a minority of cases. Wastewater surveillance could determine the onset and extent of RSV circulation in the absence of sensitive case detection, but to date, studies of RSV in wastewater are few. We measured RSV RNA concentrations in wastewater solids from 176 sites during the 2022-2023 RSV season and compared those to publicly available RSV infection positivity and hospitalization rates. Concentrations ranged from undetectable to 107 copies per gram. RSV RNA concentration aggregated at state and national levels correlated with infection positivity and hospitalization rates. RSV season onset was determined using both wastewater and clinical positivity rates using independent algorithms for 14 states where both data were available at the start of the RSV season. In 4 of 14 states, wastewater and clinical surveillance identified RSV season onset during the same week; in 3 states, wastewater onset preceded clinical onset, and in 7 states, wastewater onset occurred after clinical onset. Wastewater concentrations generally peaked in the same week as hospitalization rates but after case positivity rates peaked. Differences in onset and peaks in wastewater versus clinical data may reflect inherent differences in the surveillance approaches.