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ContextForest microclimates differ from regional macroclimates because forest canopies affect energy fluxes near the ground. However, little is known about the environmental drivers of understorey temperature heterogeneity and its effects on species assemblages, especially at landscape scales.ObjectivesWe aimed to identify which temperature variables best explain the landscape-scale distribution of forest vegetation and to disentangle the effects of elevation, terrain attributes and canopy cover on understorey temperatures.MethodsWe measured growing season air temperature, canopy cover and plant community composition within 46 plots established across a 400-km2 area in Czech Republic. We linked growing season maximum, mean and minimum temperatures with elevation, canopy cover and topographic proxies for heat load, topographic position, soil moisture and cold air drainage, and created fine-scale topoclimatic maps of the region. We compared the biological relevance of in situ measured temperatures and temperatures derived from fine-scaled topoclimatic maps and global WorldClim 2 maps.ResultsMaximum temperature was the best predictor of understorey plant species composition. Landscape-scale variation in maximum temperature was jointly driven by elevation and terrain topography (\\[R_adj.^2\\] = 0.79) but not by canopy cover. Modelled maximum temperature derived from our topoclimatic maps explained significantly more variation in plant community composition than WorldClim 2 grids.ConclusionsTerrain topography creates landscape-scale variation in maximum temperature, which in turn controls plant species assembly within the forest understorey. Maximum temperature is therefore an important but neglected microclimatic driver of species distribution across landscapes.

In light of global climate change, ecological studies increasingly address effects of temperature on organisms and ecosystems. To measure air temperature at biologically relevant scales in the field, ecologists often use small, portable temperature sensors. Sensors must be shielded from solar radiation to provide accurate temperature measurements, but our review of 18 years of ecological literature indicates that shielding practices vary across studies (when reported at all), and that ecologists often invent and construct ad hoc radiation shields without testing their efficacy. We performed two field experiments to examine the accuracy of temperature observations from three commonly used portable data loggers (HOBO Pro, HOBO Pendant, and iButton hygrochron) housed in manufactured Gill shields or ad hoc, custom‐fabricated shields constructed from everyday materials such as plastic cups. We installed this sensor array (five replicates of 11 sensor‐shield combinations) at weather stations located in open and forested sites. HOBO Pro sensors with Gill shields were the most accurate devices, with a mean absolute error of 0.2°C relative to weather stations at each site. Error in ad hoc shield treatments ranged from 0.8 to 3.0°C, with the largest errors at the open site. We then deployed one replicate of each sensor‐shield combination at five sites that varied in the amount of urban impervious surface cover, which presents a further shielding challenge. Bias in sensors paired with ad hoc shields increased by up to 0.7°C for every 10% increase in impervious surface. Our results indicate that, due to variable shielding practices, the ecological literature likely includes highly biased temperature data that cannot be compared directly across studies. If left unaddressed, these errors will hinder efforts to predict biological responses to climate change. We call for greater standardization in how temperature data are recorded in the field, handled in analyses, and reported in publications. We performed two field experiments to examine the accuracy of three common portable temperature sensors (HOBO Pro, HOBO Pendant, and iButton hygrochron) housed in manufactured Gill shields or ad‐hoc, custom‐fabricated shields constructed from everyday materials such as plastic cups. Our results indicate that, due to variable shielding practices, the ecological literature includes highly biased temperature data that cannot be compared directly across studies. We call for greater standardization in how climate data are recorded in the field, handled in analyses, and reported in publications.

Fire has transformative effects on soil biological, chemical, and physical properties in terrestrial ecosystems around the world. While methods for estimating fire characteristics and associated effects aboveground have progressed in recent decades, there remain major challenges in characterizing soil heating and associated effects belowground. Overcoming these challenges is crucial for understanding how fire influences soil carbon storage, biogeochemical cycling, and ecosystem recovery. In this paper, we present a novel framework for characterizing belowground heating and effects. The framework includes (1) an open-source model to estimate fire-driven soil heating, cooling, and the biotic effects of heating across depths and over time (Soil Heating in Fire model; SheFire) and (2) a simple field method for recording soil temperatures at multiple depths using self-contained temperature sensor and data loggers (i.e., iButtons), installed along a wooden stake inserted into the soil (i.e., an iStake). The iStake overcomes many logistical challenges associated with obtaining temperature profiles using thermocouples. Heating measurements provide inputs to the SheFire model, and modeled soil heating can then be used to derive ecosystem response functions, such as heating effects on microorganisms and tissues. To validate SheFire estimates, we conducted a burn table experiment using iStakes to record temperatures that were in turn used to fit the SheFire model. We then compared SheFire predicted temperatures against measured temperatures at other soil depths. To benchmark iStake measurements against those recorded by thermocouples, we co-located both types of sensors in the burn table experiment. We found that SheFire demonstrated skill in interpolating and extrapolating soil temperatures, with the largest errors occurring at the shallowest depths. We also found that iButton sensors are comparable to thermocouples for recording soil temperatures during fires. Finally, we present a case study using iStakes and SheFire to estimate in situ soil heating during a prescribed fire and demonstrate how observed heating regimes would influence seed and tree root vascular cambium survival at different soil depths. This measurement-modeling framework provides a cutting-edge approach for describing soil temperature regimes (i.e., soil heating) through a soil profile and predicting biological responses.

Climate change threatens endemic island ectothermic reptiles that display small population sizes and temperature‐dependent sex determination (TSD). Studies of captive Galapagos tortoises demonstrate type A TSD with warmer incubation temperatures producing females. However, there are few published data from free‐living Galapagos tortoises on incubation temperature regimes, and none on hatchling sex ratios in the wild or the potential impacts of climate change on future sex ratios. We sought to address these deficits by quantifying incubation temperatures of nests and sex ratios of juvenile tortoises along an elevation gradient on Santa Cruz Island. We focused on three geographically separated nesting zones with mean elevations of 14 m (lower), 57 m (middle), and 107 m (upper) above sea level. Nest temperatures in 54 nests distributed across the three nesting zones were measured every 4 h throughout the incubation period using iButton thermochrons. We used coelioscopy to conduct visual exams of gonads to determine the sex of 40 juvenile tortoises from the three nesting zones. During the middle trimester of incubation, the period during which sex is determined in turtles, mean nest temperatures were 25.75°C (SD = 1.08) in the upper zone, and 27.02°C (SD = 1.09), and 27.09°C (SD = 0.85) in the middle and lower zones, respectively. The proportion of juveniles that was male increased from 11.1% in the lower zone and 9.5% in the middle zone, to 80% in the upper zone. A ca. 50 m increase in elevation induced a decrease of >1.25°C in mean nest temperature during the second trimester of incubation. Over the same elevation change, the proportion of males in the juvenile tortoise population increased by ca. 70%. Temperatures on Galapagos are predicted to increase by 1‐4°C over the next 50 years, which is likely to increase the frequency of female tortoises across the archipelago. We sought to improve our understanding of the impact of climate on the sex ratio of free‐living Galapagos tortoises; a species with temperature‐dependent sex determination, by quantifying sex ratios of juvenile tortoises and nest temperatures along an elevation gradient on Santa Cruz Island. A ca. 50 m increase in elevation induced a decrease in > 1.25°C in mean nest temperature in the second third of incubation. Over the same elevation change, the proportion of males in the juvenile tortoise population increased by ca. 70%.

Adverse climatic conditions can decrease reproductive success by reducing parents’ ability to provide enough resources to growing young. Here, we address the hypothesis that helpers at the nest can buffer the negative effects of challenging climatic (cool and wet) conditions in cooperatively breeding superb fairy-wrens. We first established that public records are adequate to quantify climate effects: temperatures recorded at a nearby meteorological station explained total offspring care equally well as microclimate temperatures measured inside the nest and near the nest site. We then compared the effects of temperature and rainfall on offspring care in pairs with and without helpers and found that (i) at lower, more energetically challenging temperatures, nestlings receive larger prey and more prey biomass, and females brood young nestlings more, but these increases in care occur regardless of helper presence; (ii) groups with helpers provide more prey biomass during dry conditions, but higher rainfall in the previous week reduces this to the level of unassisted pairs. Overall, cooperative breeding in superb fairy-wrens does not appear to buffer challenging (cool and wet) conditions: helpers do not mitigate the effects of cool temperatures and although groups with helpers deliver more food, this benefit disappears during periods with high rainfall.

•Use of continuous methods for temperature monitoring captured higher number of fever episodes.•4CMenB batches MAT scores did not correlate with fever episodes.•The vaccine batches released were not associated with increased adverse events. Better understanding of vaccine reactogenicity is crucial given its potential impact upon vaccine safety and acceptance. Here we report a comparison between conventional and novel (continuous) methods of monitoring temperature and evaluate any association between reactogenicity and the monocyte activation test (MAT) employed for testing four-component capsular group B meningococcal vaccine (4CMenB) batches prior to release for clinical use in Europe. Healthy 7–12-week-old infants were randomised in two groups: group PCV13 2 + 1 (received pneumococcal conjugate vaccine 13 valent (PCV13) at 2, 4 and 12 months) and group PCV13 1 + 1 (received reduced schedule at 3 and 12 months). In both, infants received the remaining immunisations as per UK national schedule (including 4CMenB at 2, 4 and 12 months of age). Fever was measured for the first 24 h after immunisations using an axillary thermometer and with a wireless continuous temperature monitoring device (iButton®). To measure the relative pyrogenicity of individual 4CMenB batches, MAT was performed according to Ph. Eu. chapter 2.6.30 method C using PBMCs with IL-6 readout. Fever rates detected by the iButton® ranged from 28.7% to 76.5% and from 46.6% to 71.1% in group PCV13 2 + 1 and PCV13 1 + 1 respectively, across all study visits. The iButton® recorded a higher number of fever episodes when compared with axillary measurements in both groups (range of axillary temperature fevers; group PCV13 2 + 1: 6.7%-38%; group PCV13 1 + 1: 11.4%-37.1%). An agreement between the two methods was between 0.39 and 0.36 (p < 0.001) at 8 h’ time-point post primary immunisations. No correlation was found between MAT scores and fever rates, or other reported adverse events. It is likely that conventional, intermittent, fever measurements underestimates fever rates following immunisation. 4CMenB MAT scores didn’t predict reactogenicity, providing reassurance that vaccine batches with the highest acceptable pyrogen level are not associated with an increase in adverse events. Clinicaltrials.gov identifier: NCT02482636.

Urban climatologist particularly those interested in Urban Heat Island (UHI), require some form of explanations to UHI variations at both spatial and temporal scales in cities. Temperature cooling and warming rate can be use as a form of explanations for spatial and temporal variations for UHI intensity characteristics of an area. This study therefore, assessed variations in temperature warming and cooling rates in Jalingo. The study used temperature data collected at six locations representing six different thermal climate zones in the study area. Temperature data were collected for the period of 90 days thirty days in each of rainy season, dry season, and hamattan period. Simple statistical analysis was performed to determine the warming and cooling rates. The results indicate that temperature warm and cool differently in the study area. The results also revealed that general warming in the area within the study period begins at 8:00 h local time (GMT +1) with warming rate ranging from 0.94°C to 1.75°C across locations with a mean of 1.30°C. Cooling starts at 15:00 h ranging from -0.88°C to -1.84°C with an average of -1.48°C. It is recommended that environmental planners particularly the urban planners and Architectures should take into considerations the warming and cooling rates in their building design and also embrace appropriate landscaping to improve thermal comfort.

Demographic studies of many bird species are challenging because their nests are cryptic, resulting in few nests being found. To maximize statistical power, methods are needed that minimize disturbance while yielding as much information per nest as possible. One way to meet these objectives is to use miniature thermal data loggers to precisely date nest fates. Our objectives, therefore, were to (1) examine the possible effect of thermal data loggers on nest success through hatching by grass-and shrub-nesting songbirds that differed in their parasite egg-accepting and -rejecting behavior, (2) examine the effect of using daily temperature data versus less frequent nest-visit data on statistical power, bias, and precision when estimating the daily survival rate (DSR) for nests, and (3) compare these two approaches using a simulation study and field data. We monitored the survival of nests located in agricultural landscapes and used a binomial logistic regression with main effects for data-loggers and parasite-accepting or-rejecting status and their interaction. We also compared maximum likelihood–derived DSR for differences in estimated rates, precision, and sample sizes with both data collected in the field and simulated with varying sample sizes and visit frequencies. We found no evidence that thermal data loggers had any effect on hatching rates either for all species or for parasite egg-accepting and -rejecting species, separately. Both our simulation and analysis of real nest data indicated that use of data loggers increased the statistical power from each nest studied by increasing effective sample sizes and precision of DSR estimates compared to in-person visits. We also found a negative bias in DSR estimates with longer visit intervals, which use of data-loggers removed. Both the results of simulated-and field-data analyses suggest that future studies of nest survival can be improved by automated nest monitoring by removing a source of bias and providing more time to find additional nests. Estudios demográficos de muchas especies son un reto por que sus nidos son crípticos resultando en pocos nidos encontrados. Para maximizar el poder estadístico, se requieren métodos que minimicen el disturbio, produciendo la mayor cantidad de información por nido posible. Una forma de cumplir con estos objetivos, es usar medidores de temperatura miniatura para estimar la fecha del destino final del nido con precisión. Consecuentemente, nuestros objetivos fueron (1) examinar el posible efecto de los medidores térmicos en el éxito de nacimiento de nidos para aves cantoras anidando en pastos y arbustos con diferentes comportamientos de aceptación y rechazo de huevos de parásitos, (2) examinar el efecto del uso diario de datos de temperatura versus visitas al nido menos frecuentes sobre el poder estadístico, sesgo y precisión en la estimación de la tasa diaria de supervivencia (DSR) y (3) comparar estas dos aproximaciones usando estudios de simulación y datos de campo. Monitoreamos la supervivencia de los nidos ubicados en paisajes agrícolas y utilizamos una regresión logística binomial con efectos principales para el medidor de temperatura y el estatus de aceptación o rechazo de los huevos de parásitos y su interacción. También comparamos estimados de DSR derivados por medio de máxima verosimilitud para las diferencias en las tasas estimadas, precisión y tamaños de muestra para datos colectados en el campo y simulados con diferentes tamaños de muestra y frecuencia de visita. No encontramos evidencia que los medidores térmicos de temperatura tuvieran un efecto sobre las tasas de nacimiento, ni entre las especies, ni para especies que aceptan o rechazan huevos de especies parasitas por separado. Nuestras simulaciones y el análisis de nidos reales indicaron que el uso de los medidores incrementan el tamaño efectivo de la muestra y la precisión en los estimados de DSR comparado con las visitas en persona. También encontramos un sesgo negativo en los estimados de DSR con intervalos de visita prolongados y que los medidores de temperatura incrementan el poder estadístico de cada nido estudiado, incrementan la precisión de los estimados y remueven sesgos negativos en DSR. Los resultados de los análisis de datos simulados y reales sugieren que estudios futuros sobre supervivencia de nidos pueden ser mejorados por medio del monitoreo automatizado de los nidos, removiendo la fuente del sesgo y proporcionando más tiempo para encontrar nidos adicionales.

Nest attendance is an important determinant of avian reproductive success, and identifying factors that influence the frequency and duration of incubation recesses furthers our understanding of how incubating birds balance their needs with those of their offspring. We characterized the frequency and timing (start time, end time, and duration) of incubation recesses for mallard (Anas platyrhynchos) and gadwall (Mareca strepera) hens breeding in Suisun Marsh, California, USA, and examined the influences of day of year, ambient temperature at the nest, incubation day, and clutch size on recess frequency and timing using linear mixed models. Mallard, on average, took more recesses per day (1.69 ± 0.80, mean ± standard deviation) than did gadwall (1.39 ± 0.69), and 45% of mallard nest‐days were characterized by two recesses, while only 27% of gadwall nest‐days were characterized by two recesses. Mallard morning recesses started at 06:14 ± 02:46 and lasted 106.11 ± 2.01 min, whereas mallard afternoon recesses started at 16:39 ± 02:11 and lasted 155.39 ± 1.99 min. Gadwall morning recesses started at 06:30 ± 02:46 and lasted 91.28 ± 2.32 min, and gadwall afternoon recesses started at 16:31 ± 01:57 and lasted 192.69 ± 1.89 min. Mallard and gadwall started recesses earlier in the day with increasing ambient temperature, but later in the day as the season progressed. Recess duration decreased as the season progressed and as clutch size increased, and increased with ambient temperature at the nest. The impending darkness of sunset appeared to be a strong cue for ending a recess and returning to the nest, because hens returned to their nests earlier than expected when recesses were expected to end after sunset. Within hens, the timing of incubation recesses was repeatable across incubation days and was most repeatable for mallard afternoon recesses and on days in which hens took only one recess. Hens were most likely to be away from nests between 04:00 and 07:00 and between 16:00 and 19:00; therefore, investigators should search for nests between 07:00 and 16:00. Our analyses identified important factors influencing incubation recess timing in dabbling ducks and have important implications for nest monitoring programs. We characterized the frequency and timing (start time, end time, and duration) of incubation recesses for mallard (Anas platyrhynchos) and gadwall (Mareca strepera) hens breeding in Suisun Marsh, California, USA, and examined the influences of day of year, ambient temperature at the nest, incubation day, and clutch size on recess frequency and timing. Mallard, on average, took more recesses per day than did gadwall. Mallard and gadwall started recesses earlier in the day with increasing ambient temperature, but later in the day as the season progressed. Recess duration decreased as the season progressed and as clutch size increased, and increased with ambient temperature at the nest. The impending darkness of sunset appeared to be a strong cue for ending a recess and returning to the nest, because hens returned to their nests earlier than expected when recesses were expected to end after sunset. Our analyses identified important factors influencing incubation recess timing in dabbling ducks and have important implications for nest monitoring programs.

Thermal data loggers have been used to monitor nest activity for a variety of avian species, primarily by identifying a difference in temperature between the relatively cool environment and the nest, which is warmed by nestlings or attendant adults. Many grassland songbirds, however, nest in warm environments where ambient and nest temperatures are frequently similar, which may limit the ability to identify nesting events from temperature data. Here, we evaluate the efficacy and potential impact of monitoring nests of grassland songbirds with thermal data loggers. We focus on a grassland-obligate species, Botteri's Sparrow (Peucaea botterii), that nests in hot, semiarid grasslands. We located and monitored 225 nests in southeastern Arizona, USA, and placed data loggers below the surface of the nest lining at a subset of 28 nests. To contrast nest temperatures with ambient temperatures, we placed a second data logger in similar vegetation within 3 m of the nest. Data loggers did not affect daily survival rates of nests. We were able to identify the date the nesting attempt ended (i.e., failure or fledging) correctly for all nests based on temperature data recorded during the cool period of the daily temperature cycle when data loggers placed below the nest lining averaged 3.9 °C warmer than the environment. During the hot period of the daily cycle, we were able to identify nest cessation correctly for only 46% of nests. Our study demonstrates that thermal data loggers can be used to monitor nest survival of grassland birds successfully provided that ambient temperatures are measurably lower than nest temperatures for at least part of the daily cycle. This provides an alternative to intensive observer-based monitoring that can increase the precision of survival estimates while potentially reducing cost, effort, and risk of disturbance to this group of high conservation concern. Sensores térmicos (“thermal data loggers”) han sido usados para monitorear la actividad de anidación de varias especies de aves, principalmente identificando la diferencia de temperatura entre el ambiente relativamente fresco y el nido, que es calentado por anidamiento o por ocupantes adultos. Muchas aves canoras, sin embargo, anidan en ambientes tibios en donde las temperaturas ambientales y del nido son frecuentemente similares, lo que podría limitar la habilidad de identificar los eventos de anidación a partir de datos de temperatura. Aquí evaluamos la eficacia y el impacto potencial de monitorear nidos de aves canoras con sensores térmicos. Nos enfocamos en una especie de asociación obligatoria a pastizales, el chingolo de Botteri. (“Peucaea botterii”) que anida en pastizales cálidos semiáridos. Localizamos y monitoreamos 225 nidos en el sureste de Arizona, EEUU, y colocamos sensores térmicos bajo el recubrimiento del nido en una submuestra de 28 nidos. Para contrastar la temperatura de los nidos con la temperatura ambiental, colocamos un sensor térmico sobre vegetación similar a una distancia menor de 3 m del nido. Los sensores térmicos no afectaron la tasa de supervivencia diaria de los nidos. Pudimos identificar la fecha en que el intento de anidación terminó (es decir, fallo o emancipación) correctamente para todos los nidos con base en la temperatura registrada durante las horas más frías del ciclo diario cuando los sensores térmicos que estaban bajo la superficie del recubrimiento del nido marcaban una temperatura 3.9 °C mayor a la temperatura ambiental. Durante las horas más cálidas del ciclo diario pudimos identificar el final de la anidación solamente en el 46% de los nidos. Nuestro estudio demuestra que los sensores térmicos pueden ser usados para monitorear la supervivencia del nido de aves de pastizal exitosamente dado que las temperaturas ambientales son considerablemente más bajas que las temperaturas del nido al menos durante parte del ciclo diario. Esto da una alternativa al monitoreo intensivo basado en observadores que puede aumentar la precisión de las estimaciones de sobrevivencia y a la vez podría reducir costos, esfuerzos y riesgos de perturbación a este grupo de alto interés de conservación. Palabras clave: abundancia de nidos, efecto del observador, éxito de nidos, iButton, temperatura de nidos.