Bee Activity Research Articles

Stingless Bee Foraging Activity Related to Environmental Aspects.

The environment where bee colonies are inserted must provide the necessary resources for their survival. Given this, any biotic and abiotic changes in the environment can affect the development and survival of the colonies. We evaluated the foraging activity of Plebeia droryana (Friese), Scaptotrigona bipunctata (Lepetelier), and Melipona quadrifasciata (Lepetelier) in areas with different land uses and land cover. These areas were classified as predominantly (i) urbanized/forest (CDA-Cidade das Abelhas), (ii) agricultural (FER-Fazenda Experimental da Ressacada), and (iii) with dense vegetation (SFB-Sitio Florbela). We correlated the morphometric characteristics of the bees with the pollen load transported. Four colonies from each species were installed in the three areas. We recorded light, wind speed, humidity, and temperature and counted the foragers returning with nectar, pollen, and resin. Plebeia droryana and S. bipunctata collected more resin and nectar in with dense vegetation area compared to agricultural area. Scaptotrigona bipunctata collected more pollen in urbanized/forest area and with dense vegetation area, and M. quadrifasciata did not show differences in foraging activity between areas. Plebeia droryana and M. quadrifasciata showed moderate and strong correlations between morphometric characteristics and pollen load. SFB had higher luminosity and wind speed. CDA had higher average temperature. FER had higher humidity. The three species showed positive and negative correlations between temperature and light and foraging in the different areas. Smaller species showed a higher gathering of resources in the area predominantly covered by dense vegetation. The reduction of vegetation cover can affect the resource collection activity of stingless bees.

Intelligent beehive monitoring system based on internet of things and colony state analysis

Bees play a crucial role in terrestrial ecosystems. However, beekeepers are unable to monitor the state of beehives (bees and environment) all the time, which often results in bees escaping or even dying. Currently, some researchers provided the scheme of intelligent beehive monitoring system equipped with the Internet of Things (IoT), There remain two challenges: accurately monitor the environmental status around the hive and accurately track and monitor bees in real time. With the development of the IoT and computer vision algorithms, we hope to provide an automated and efficient system to meet the above challenges. In this paper, we proposed a hive monitoring system, and build a visualization module in the cloud to monitor the activity of bee colonies and the environmental dynamic changes. (1) We proposed a multi-bee tracking algorithm to solve the problem of monitoring bees at the door of the hive; (2) we constructed a dataset containing various complex scenes, named BEE22, for training and testing the performance of our algorithm; (3) we designed a bee counting rule, based on results of multi-bee tracking algorithm, to reasonably count the bees entering or leaving the beehive; (4) we have deployed multiple sensors around(center, margin, door, and environment) the hive to accurately reflect the changes in the environment around the hive. Experimental results demonstrate the effectiveness and excellence of our system. In particular, the tracking performance of the multi-bee tracking algorithm reaches 83.5 % ± 0.7 % Multiple Object Tracking Accuracy (MOTA) and 77.3 %±0.2 % Multiple Object Tracking Precision (MOTP), speeds up to 16 frames per second, compared with other algorithms, MOTA and Identity F1 Score (IDF1) are improved by 5.4 % and 8.2 % respectively. Moreover, our counting algorithm also achieved excellent results, with root mean square error (RMSE) of 1.3 ± 0.1, 0.2 ± 0.0, and 1.6 ± 0.1 in counting the number of bees current, entry, and out scene in an episode, respectively. After that, the system will be deployed and monitored for a long time in the actual scenario, it was found that the activity of bees decreased significantly under heavy rainfall conditions. Additionally, the activity of the bee colony will also increase accordingly, when the amplitude is 500 dB to 2000 dB, the temperature of the center of the beehive is 25 °C to 37 °C, and the humidity is 48 % to 67 %. In summary, our system can provide valuable information for bee farmers to make control decisions on hives.

Perbandingan aktivitas harian dua spesies lebah tanpa sengat di Sulawesi Barat

Stingless bees are spread across several islands in Indonesia, including Sulawesi. There have been no reports of daily activity of stingless bees in West Sulawesi Province. Therefore, this study aims to identify types of stingless bees in West Sulawesi, measure their daily activities, and their relationship with environmental parameters. The research was conducted in the highlands (Taupe Village, Mamasa Regency, 1,340 m dpl) and the lowlands (Mirring Village, Polewali Mandar Regency, 63 m dpl). Daily activity data collected which includes the activities in and out of the nest, carrying pollen, and throwing away rubbish. Daily activity observations use the scan sampling method. The results of the research show that the type of bee in Taupe Village is Wallacetrigona incisa (Sakagami & Inoue), while in Mirring Village is Tetragonula sapiens (Cockerell). There was no significant difference in the daily activity of W. incisa in the highlands and T. sapiens in the lowlands (P > 0.05). Significant differences were seen between the activities of leaving and entering the nest and the activities of carrying pollen and throwing away rubbish (P < 0.05). Wind speed is an environmental parameter that influences pollen-carrying activity in T. sapiens in the lowlands (r = 0.83; P = 0.002). Environmental parameters greatly influenced the daily activity of W. incisa at 12.00 pm, with an influence of 93% (P < 0.05). The results of this study indicate that differences in the type and habitat of bees and environmental factors cause differences in the daily activity of stingless bees.

Impact of the annular solar eclipse on December 26, 2019 on the foraging visits of bees

Solar eclipse has remarkable effect on behavior of animals. South India experienced a 97% magnitude annular eclipse on December 26, 2019 during 08:04–11:04 h with the totality phase appeared during 09:25–09:30 h. We investigated whether the foraging activity of the bees was limited by the eclipse, what bees are affected most, and which part of the eclipse was critical for bee activities to understand how a group of insects that rely the Sun, the sunlight, and the sun rays for their navigation and vision behaves to the eclipse. We opted to watch the bees in their foraging ground, and selected the natural flower populations of Cleome rutidosperma, Hygrophila schulli, Mimosa pudica, and Urena sinuata—some of the bee-friendly plants—to record the visitor richness and visitation rate on the flowers on eclipse and non-eclipse days and during the hour of totality phase and partial phase of the eclipse. Fewer flower-visiting species were recorded on the eclipse day than on the non-eclipse days, but in the period of totality, very few bee species were active, and limited their activity to only one population of C. rutidosperma. Visits of honey bees and stingless bees were affected most, but not that badly of solitary bees and carpenter bees. Bees, particularly the social bees use Sun for navigation and deciphering information on forage sources to fellow workers. The eclipse, like for many other animals, might hamper bees’ orientation, vision, and flight.

Field agrochemical exposure impacts locomotor activity in wild bumblebees.

Agricultural intensification has been identified as one of the key causes of global insect biodiversity losses. These losses have been further linked to the widespread use of agrochemicals associated with modern agricultural practices. Many of these chemicals are known to have negative sublethal effects on commercial pollinators, such as managed honeybees and bumblebees, but less is known about the impacts on wild bees. Laboratory-based studies with commercial pollinators have consistently shown that pesticide exposure can impact bee behavior, with cascading effects on foraging performance, reproductive success, and pollination services. However, these studies typically assess only one chemical, neglecting the complexity of real-world exposure to multiple agrochemicals and other stressors. In the summer of 2020, we collected wild-foraging workers of the common eastern bumblebee, Bombus impatiens, from five squash (Cucurbita) agricultural sites (organic and conventional farms), selected to represent a range of agrochemical, including neonicotinoid insecticide, use. For each bee, we measured two behaviors relevant to foraging success and previously shown to be impacted by pesticide exposure: sucrose responsiveness and locomotor activity. Following behavioral testing, we used liquid chromatography-tandem mass spectrometry (LC-MS/MS) chemical analysis to detect and quantify the presence of 92 agrochemicals in each bumblebee. Bees collected from our sites did not vary in pesticide exposure as expected. While we found a limited occurrence of neonicotinoids, two fungicides (azoxystrobin and difenoconazole) were detected at all sites, and the pesticide synergist piperonyl butoxide (PBO) was present in all 123 bees. We found that bumblebees that contained higher levels of PBO were less active, and this effect was stronger for larger bumblebee workers. While PBO is unlikely to be the direct cause of the reduction in bee activity, it could be an indicator of exposure to pyrethroids and/or other insecticides that we were unable to directly quantify, but which PBO is frequently tank-mixed with during pesticide applications on crops. We did not find a relationship between agrochemical exposure and bumblebee sucrose responsiveness. To our knowledge, this is the first evidence of a sublethal behavioral impact of agrochemical exposure on wild-foraging bees.

The use of phytocomposition in beekeeping as an ecological method for stimulating the vital activity and immune status of honey bees

The use of phytocomposition in beekeeping as an ecological method for stimulating the vital activity and immune status of honey bees

Technological methods of limiting the reproductive activity of queen bees in conditions of honey collection

The study of the biological characteristics of the development of bee colonies, the ethology of bees, the influence of the various factors on their life activities contributes to the development and implementation of new highly efective technologies of keeping and reproduction. Of particular interest is the study of the stimulating efect of diferent numbers of brood of diferent ages in the nest of a bee colony on the trophic connections of honey bees with the biological diversity of entomophilous plants, the change in physiological characteristics of diferent generations of bees in modern changing natural and climatic conditions of unstable ecotypes. This paper presents the data of experimental studies on the influence on the biological potential of bee colonies of various technological methods of regulating the reproductive activity of queen bees. The work aims to study the technological methods of regulating the reproductive activity of queen bees. The following research methods were used: zootechnical (selection of groups of analogues, signs of bee purebredness, brood accounting), analytical (analysis of literature data and research results) and statistical. Biometric data processing was carried out on a PC using MS Excel software with built-in statistical functions. Results. As a result of the study, it was found that bee families, where the reproductive activity of queen bees was limited by the use of an isolation cage, had the highest productivity indicators. It has been proved that prolonged (15 days or more) restriction of the reproductive activity of queen bees negatively afects the strength of bee colonies and their preparation for a prolonged state of hypobiosis. Conclusions. It was found that there is a complex relationship between brood rearing by bee colonies and their productivity. The absence of brood has led to an increase in the supply of nectar only for 12-15 days. Currently, due to the lack of replenishment with young bees, bee colonies have lost their strength and weakened. It has been proven that the most efective technological method of regulating the reproductive activity of queen bees in hull hives is the use of dividing grids and the mandatory presence of brood of diferent ages. For the efective use of honey collection, it is important not only to increase the maximum number of bees before the start of the main honey collection, but also to limit the feeding of a large number of larvae in time when they are no longer needed. During a short-term honey collection, it is necessary to limit the reproductive activity of the queen bee, and during the long one, it should be limited only in the second half of honey collection. Key words: bee colony, Ukrainian steppe breed, isolation, brood, reproductive activity, honey collection, honey productivity.

First Report of Nesting Habits, Nest Architecture and Foraging Behaviour of the Stingless bee, Tetragonula (Tetragonula) ruficornis (Smith) (Hymenoptera: Apidae: Meliponini) from India

The present study aimed to understand nesting habits, nest architecture, and foraging behavior of the stingless bee, Tetragonula (Tetragonula) ruficornis Smith, a widespread species in the north Indian plains from Varanasi to Punjab. Among the 47 wild, unmanaged colonies studied, 27 were situated in the cavities of tree trunks and 20 in the cavities of building walls. The internal nest structure revealed that brood cells were arranged in clusters at the center of the cavity with encircling pollen and honey pots. Further, the natural nesting cavity’s total length, width, and height varied from 105 to 168 mm, 129 to 216 mm, and 283 to 472 mm, respectively. The foraging activity of outgoing and incoming foragers of T. ruficornis varied significantly during different hours of the day, across the seasons and prevailing weather conditions. Further, activity was limited to daytime from 08:00 to 18:00 h, with peak activity of outgoing and incoming forager bees between 10:00 and 12:00 h during all seasons. Irrespective of seasons, the foraging activity of outgoing, pollen, and nectar foragers was at its maximum at 12:00 h. However, foraging ceased during December and January due to low temperatures, while peak activity was observed during April. The foraging pattern showed a significant positive correlation with mean monthly maximum and minimum temperatures and a significant negative correlation with relative humidity. The current investigation delivers crucial information on nest architecture and foraging behavior, which could be exploited for designing bee hives and utilization in directed pollination services.

Intake of imidacloprid in lethal and sublethal doses alters gene expression in Apis mellifera bees

Bees are important pollinators for ecosystems and agriculture; however, populations have suffered a decline that may be associated with several factors, including habitat loss, climate change, increased vulnerability to diseases and parasites and use of pesticides. The extensive use of neonicotinoids, including imidacloprid, as agricultural pesticides, leads to their persistence in the environment and accumulation in bees, pollen, nectar, and honey, thereby inducing deleterious effects. Forager honey bees face significant exposure to pesticide residues while searching for resources outside the hive, particularly systemic pesticides like imidacloprid. In this study, 360 Apis mellifera bees, twenty-one days old (supposed to be in the forager phase) previously marked were fed syrup (honey and water, 1:1 m/v) containing a lethal dose (0.081 μg/bee) or sublethal dose (0.00081 μg/bee) of imidacloprid. The syrup was provided in plastic troughs, with 250 μL added per trough onto each plastic Petri dish containing 5 bees (50 μL per bee). The bees were kept in the plastic Petri dishes inside an incubator, and after 1 and 4 h of ingestion, the bees were euthanised and stored in an ultra-freezer (−80 °C) for transcriptome analysis. Following the 1-h ingestion of imidacloprid, 1516 genes (73 from lethal dose; 1509 from sublethal dose) showed differential expression compared to the control, while after 4 h, 758 genes (733 from lethal dose; 25 from sublethal) exhibited differential expression compared to the control. All differentially expressed genes found in the brain tissue transcripts of forager bees were categorised based on gene ontology into functional groups encompassing biological processes, molecular functions, and cellular components. These analyses revealed that sublethal doses might be capable of altering more genes than lethal doses, potentially associated with a phenomenon known as insecticide-induced hormesis. Alterations in genes related to areas such as the immune system, nutritional metabolism, detoxification system, circadian rhythm, odour detection, foraging activity, and memory in bees were present after exposure to the pesticide. These findings underscore the detrimental effects of both lethal and sublethal doses of imidacloprid, thereby providing valuable insights for establishing public policies regarding the use of neonicotinoids, which are directly implicated in the compromised health of Apis mellifera bees.

Foraging Dynamics of Western Honey Bee <i>APIs Mellifera</i> L. On Litchi

Honey bee Apis mellifera L. is one of the most important pollinating insect of litchi. Foraging behaviour of pollinators is greatly influenced by many environmental factors including temperature, relative humidity, wind speed, rainfall etc. Variation in the foraging behaviour of A. mellifera in relation to environmental factors has been studied during March-April 2022 on nectar rich litchi flora. Temperature > 30°C had negative impact on bee activity with correlation coefficient of -0.71, -0.41 and -0.21 for outgoing, pollen collecting and nectar collecting bees, respectively. The temperature, > 15°C and upto 30°C, on other hand exhibited positive impact on outgoing bees (r = 0.66), nectar collecting bees (r = 0.76) and pollen collecting bees (r = 0.77). Distinct correlation had also been found between the foraging activity and relative humidity, rainfall and diurnal variation.

Can Bees Detect Perfluorooctane Sulfonate (PFOS)?

The European honey bee (Apis mellifera) is an important crop pollinator threatened by multiple stressors, including exposure to contaminants. Perfluorooctane sulfonate (PFOS) is a persistent global contaminant that accumulates and biomagnifies in food chains and is detected in honey. Even sublethal exposure to PFOS is detrimental to bee health, but exposure routes are unclear and nothing is known about bee response (detection, avoidance, or attraction) to PFOS. Using Y-mazes, we studied the response of individual bees to PFOS-spiked sugar syrup at four concentrations, 0.02, 30, 61 and 103 µg L-1. Bee activity, choice behavior, and drink duration for unspiked and spiked sugar syrup was recorded for 10 min in the Y-maze system. Most bees (≥80%) tasted and then drank the sugar syrup solutions, including the PFOS-contaminated syrup. Only at 61 and 103 µg L-1 did bees significantly avoid drinking PFOS-spiked syrup, and only when given a choice with unspiked syrup. When the choice of consuming unspiked syrup was removed, the bees drank PFOS-spiked syrup at all the PFOS concentrations tested, and avoidance was not evident. Avoidance was not observed in any treatment at 0.02 or 30 µg L-1 PFOS, concentrations that are frequently reported in environmental waters in contaminated areas. These findings confirm that bees will access PFOS-contaminated resources at concentrations detrimental to the colony health, and provide evidence of potential exposure pathways that may threaten crop pollination services and also human health via food chain transfer in PFOS-contaminated areas. Environ Toxicol Chem 2024;43:1638-1647. © 2024 SETAC.

The Effects of Using Heating Panels in Smart Beekeeping Systems on Honeybee (Apis mellifera) Colonies during Winter: Worker Bee Activity

The Effects of Using Heating Panels in Smart Beekeeping Systems on Honeybee (Apis mellifera) Colonies during Winter: Worker Bee Activity

An Economic Cost/Benefit Tool to Assess Bee Pollinator Conservation, Pollination Strategies, and Sustainable Policies: A Lowbush Blueberry Case Study

Lowbush blueberry is a mass-flowering plant species complex that grows in both unmanaged wild landscapes and managed agricultural fields in northeastern regions of both the USA and Canada. During pollination, more than 120 native bee species are associated with lowbush blueberry ecosystems in Maine, USA, in addition to three commercially managed bees. Over a 29-year period, we sampled 209 lowbush blueberry fields using quadrat and transect sampling, recording both native bee and honey bee densities, honey bee hive stocking density, and native bees as a proportion of total bees. These data were used to simulate economic uncertainty in pollination. We developed a novel algorithm, the Economic Pollinator Level (EPL), to estimate bee densities that economically warrant pollination investments such as rented hives and planting bee pastures. Statistical modeling indicated both native bee and honey bee activity density predicted proportion fruit set in fields. Honey bee activity density was well predicted by hive stocking density. Proportion fruit set adequately predicted yield. EPL was most sensitive to fruit set/m2/bee and less dependent on berry weight, rented hive stocking density, hive rental cost, lowbush blueberry price, and the annual cost of planting/maintaining pollinator pastures. EPL can be used to sustainably balance economical pollination investments/decisions with bee conservation in lowbush blueberry crops and potentially other pollinator-dependent crops.

Increasing temperature and time in glasshouses increases honey bee activity and affects internal brood conditions

Honey bees are globally important pollinators, key to many aspects of ecosystem function and agricultural production. However they are facing an increasing array of stress factors. These stressors include exposure to pathogens and pesticides, agricultural intensification, and changes in climate, and likely contribute to colony dysfunction and colony losses. Here we use temperature-controlled glasshouse experiments to investigate the impact of a field-realistic temperature-range on honey bee colonies, including temperatures based on projections for near-future local conditions. We show that increased temperatures have a significant impact on honey bee worker activity, with increased worker movement in and out of colonies, particularly over 30 °C. In addition, increased glasshouse temperatures led to significantly higher brood (egg, larval and pupal cells) humidity. Finally, temperature had a more severe impact at the later end of the experiment than at the start (on worker movement and brood conditions), suggesting that colonies under stress (either due to exposure to thermal stress or glasshouse confinement) have more difficulty in manging thermoregulation. These results indicate the potential impact of higher temperatures on the healthy functioning of these important pollinators.

The Influence of Brood Survival Rates on the Behavioral Patterns, Economic Aspects and Resistant Traits of Italian Honeybee Apis mellifera L. Reared on Indian Mustard in Bihar

To better understand Apis mellifera foraging behaviour for mustard, this study examined how brood survival rates affected the species behavioural, economic and resistant traits. Out of 10 colonies used for the study, the results showed that 1 colony had a low rate of brood survival, 3 colonies had a medium rate, and 6 colonies had a high rate. In the experiment on scattered brood patterns, poor, medium and excellent brood patterns were found in 1, 2, and 7 colonies, respectively. According to the data on bee activity collected, the majority of bees were observed leaving between the hours of 9:00 and 10:00 and arriving between the hours of 16:00 and 17:00. According to the economic attributes data, colonies with high and moderate brood survival rates had more honey and pollen reserves. According to the hygienic behaviour results, colonies with high and moderate brood survival rates had 100 per cent efficiency while colonies with low brood survival rates had the lowest efficiency at 76 per cent.

Pollination ecology of Ranzania japonica (Berberidaceae), a perennial plant of a monotypic genus endemic to deep‐snow regions in Japan

AbstractPlants that bloom in early spring often face constraints on reproduction, which are influenced by low temperatures and unpredictable weather conditions that affect pollinator activity. We aimed to elucidate the pollination ecology and the mating system of Ranzania japonica (Berberidaceae), a perennial plant of a monotypic genus endemic to deep‐snow regions in Japan. We documented the flowering phenology and visiting insects in the field, and conducted pollination experiments by using artificial treatments. R. japonica was suggested to be self‐incompatible but not pollen‐limited. Fruit set varied between years, and florivory seemed to have a negative influence on fruit set. Insects from various taxa were observed to visit the flowers of R. japonica, with Eusphalerum sp. (rove beetle) being the most abundant, followed by Bombylius major and hymenopteran species. The stamen movement in response to insect visits was observed. The results of the observation and the pollination treatments suggested that small‐ and medium‐sized Hymenoptera were the main pollinators and rove beetles may also contribute to pollination in R. japonica. Because early spring weather can be unsuitable for activity of bees, rove beetles may act as supplementary pollinators of R. japonica. The role of the supplementary pollinators may be an overlooked but important aspect for understanding the pollination biology of early‐spring blooming plants.

Temporal and Spatial Foraging Activity of Indian Honey Bee (Apis cerana indica F.) at Different Migratory Sites

Migratory beekeeping increases honey production and reduces the feeding costs of stationary beekeeping during longer dearth periods. This study discerns the influence of environmental conditions on the foraging behavior of the Indian honey bee, Apis cerana indica F., at different migratory sites in Southern India. The total number of foraging bees, pollen foraging efficiency, and nectar foraging efficiency were estimated. Furthermore, the influence of environmental factors, including temperature, relative humidity, rainfall, and solar radiation, was recorded to identify its impact on the foraging behavior of honey bees. Among the climatic factors, maximum temperature (>30 °C) was the most crucial, negatively affecting bee activity with correlation coefficients of -0.83, -0.34, and -0.33 for outgoing bees, nectar, and pollen collectors, respectively. The relative humidity showed a positive impact on the frequency of worker bees moving out of the hive (r = 0.79), those coming in with nectar (r = 0.27), and pollen (r = 0.29). Rainfall hampered foraging activity, while solar radiation was found to have no significant effect on bee activity. Diurnal variations showed peak activity of bee foragers between 6.00 and 10.00 am. The visits by honey bees were significantly higher at low temperatures, solar radiation, precipitation, and high relative humidity. They made about 90% of their flower visits in the early morning, although plenty of bee flora was available throughout the day. Also, the environmental conditions at different sites strongly influenced the foraging behavior. However, the honey bees still focused their activities on favorable conditions depending on their biology and fixed their daily foraging patterns, improving beekeeping and honey production throughout the year.

Hygiene activity of bees in certain territories of Ukraine

The main results of the evaluation of the hygienic activity of bees are highlighted and it is assumed that pollution affects the behavioral patterns of bees and the general protective immune response of the body to the penetration of infection. After all, in Kharkiv, Sumy and Mykolaiv regions, an increased level of pollution was noted in connection with the approach to the zone of hostilities, in particular, the recording of flights to the territory of the apiary, shelling and the movement of heavy military equipment. We assumed that the weakening of the resistance of honey bees to diseases and the deterioration of the general immune response of the body may occur as a result of contamination of the natural environment, including feed, pollen and nectar, with various toxic substances. These substances can include heavy metals, radioactive elements, pesticides, herbicides, fungicides, antibiotics and other chemical compounds that negatively affect the health of bees and the quality of beekeeping products. It is shown that the best indicators of the activity of the hygienic behavior of bees were noted for the territory with the least anthropogenic load and the most distant from the zone of hostilities (Vinnytsia region). The hygienic behavior of bees is that they identify and remove infected or dead larvae from the hive, which can be a source of disease and parasites. This behavior is an important factor in the survival of bee colonies and maintaining productivity. Further studies include the selection of bees and beekeeping products (honey, honey) for laboratory studies to assess the possibility of their use in bioindication of environmental pollution. Bioindication is a method of measuring the quality of the environment using living organisms that respond to changes in environmental conditions. Bees are sensitive bioindicators because they forage over a large area and reflect the level of contamination in their products. Analyzing the research results, it can be concluded that in one group of bees, the indicators of the time of complete removal of dead brood for 2022–2023 had an uneven character. Fairly low indicators of hygienic activity over the two-year period were noted in the 2nd and 3rd groups of bees, as the average value of the time of complete removal of dead larvae was 22.7 and 23.5 hours, respectively. The lowest indicators of the time of removal of dead brood over the entire period of observation were noted in the 5th group of bees. However, the average indicators of this group are 6.5% lower than in the control group. When studying the hygienic behavior of bee colonies, we found that the efficiency of removing dead brood depends on the strength of the colony. A correlation between the values of hygienic activity of bees and family strength obtained in 2022 was found in the 2nd (R=0.95) and 3rd (R=0.78) groups. In 2023, a strong relationship between the indicators of the time of removal of 100% of larvae and the strength of the family was noted in the 5th (R=0.74), 1st groups (R=0.72). This indicates that stronger bee colonies have a greater ability to self-cleanse from dangerous factors that may threaten their health and productivity.

Hive Orientation and Colony Strength Affect Honey Bee Colony Activity during Almond Pollination.

The foraging activity of honey bees used to pollinate almonds was examined in relation to their hive entrance orientation and colony strength. Twenty-four colonies of honey bees, twelve in each group, were situated with their entrances facing east and west cardinal points. Bee out counts were recorded continuously and hive weight data at ∼10 min intervals from 17 February to 15 March 2023. Colony strength was assessed using the frames of adult bees (FOB) metric. East-facing hives started flight 44.2 min earlier than west-facing hives. The hive direction did not affect the timing of the cessation of foraging activity. The hive strength played a significant role: hives assessed as weak (≤3.0 FOB) commenced foraging activity 45 min later than strong hives (>3.0 FOB) and ceased foraging activity 38.3 min earlier. Hive weight data did not detect effects of either the hive direction or colony strength on the commencement and cessation of foraging activity, as determined using piecewise regression on 24 h datasets. However, the hive weight loss due to foraging activity at the start of foraging activity was significantly affected by both direction (East > West) and colony strength (Strong > Weak). Our study showed that, during almond pollination, both hive entrance exposure and hive strength have quantifiable effects on colony foraging behaviour and that these effects combine to regulate the overall foraging activity of the pollinating colonies.

Botanical Originand Extraction Methods of Philippine Stingless Bee (Tetragonula biroiFriese) Pollen and its Food Functionality: Phenolic and Flavonoid Content and Antioxidant Activity

With its high nutritional and bioactive content, bee pollen is recognized as a functional food. However, its composition is highly dependent on a range of factors, such as geographical location. In this research, we used DPPH to determine the antioxidant activity of several stingless bee (Tetragonula biroi) pollen samples sourced from five different areas in the Philippines and compare their phenolic and flavonoid content. Additionally, we compared two extraction methods: maceration (or soaking of samples) for three days and sonication for 30 minutes. Interestingly, our findings show that the phenolic content of bee pollen is weakly associated with antioxidant activity, indicating that other bioactive chemicals may play a more significant part in the antioxidant characteristics of bee pollen. Antioxidant properties based on the DPPH assay of pollen harvested from Calamba are higher compared to other samples from different geographic areas, i.e., Quezon Province, Sorsogon, Laguna, and Albay. When compared to the maceration approach, extracts generated from the sonication process had lower antioxidant activity. These findings suggest that Philippine stingless bee pollen is a potential source of bioactive compounds, and the choice of extraction method and geographic source are significant factors affecting its antioxidant activity.