Honey bee colony losses in Brazil in 2018-2019

A research was conducted to assess honey bee colony losses in Brazil, including their likely causes. Beekeepers responded to two complete annual questionnaires (n=268 in 2018 and n=254 in 2019). There was a total of 175,003 hives of Africanized honey bees (Apis mellifera Linnaeus), (µ=335 hives per beekeeper, min=9 and Max=3,600), of which 27.2% were lost. A Generalized Linear Model (GLM) for total loss (TL) and a Wald method for average loss (AL) were used to estimate 95% confidence intervals (CI) for loss rates based on year: 2018, TL=30.5%, CI (28.5-32.4), AL=39.5, CI (37.0-41.9); and 2019, TL=23.8%, CI (22.5-25.2), AL=31.3%, CI (29.5-33.1). Pesticides were speculated to be the leading cause of colony losses (47.3%), followed by climate (drought, flood, rain: 11.6%), malnutrition (lack of flowering, lack of energy and/or protein source, wrong nutrition: 9.7%), absconding (10.2%), mismanagement (wrong migratory activity, migration to mangrove, beekeeper’s personal problems: 7.9%), predators (3.9%), queen problems (2.8%), and varroa (1.6%). Other parasites, theft, toxic pollen (Brazilian sacbrood) and bushfires accounted for the remaining 5% of losses. Due to tropical temperatures, there is no substantial winter loss. In contrast, the highest incidence of losses occurred from September to January, coinciding with the intense agricultural activity. In summary, according to participants, there were significantly higher losses in 2018 compared to 2019, with pesticides alleged to be the main cause of honey bee colony losses in Brazil. However, beekeepers usually multiply colonies during the following season, sustaining pollination and honey production, thereby supporting agricultural activity.

Ovipositor sources for queen-rearing of honey bee (Apis mellifera) revealed inheritable maternal effect on reared queen

Queen is arguably the most important member of a honey bee colony, and queen quality is crucial for honey bee colony growth and development. In this study, queens were reared with eggs laid in queen cells (QE), eggs laid in worker cells (WE) and 2-day old larvae in worker cells (L). Those physiological indexes (the weight, thorax size and number of ovarioles) of newly reared queens in each group were measured. Moreover, the reproductive potential of the newly reared queens and foraging ability of worker bees laid by the newly reared queens in each group were further explored. In addition, we also examined whether maternal effects would be transmitted to the offspring queens in honey bee. We found that the weight, number of ovarioles and thorax weight of newly emerged queens in QE were significantly higher than those in WE and L, suggesting the reproductive potential was stronger in QE group than WE and L group. Furthermore, offspring worker bees and queens of QE queens had higher weight at emergence than those from the other two groups. This study proved profound honey bee maternal effects on queen quality, which can be transmitted to their offspring. Our results of the present study were important for improving queen quality and promoting the development of beekeeping and agriculture.

Remembrances of a Honey Bee Biologist

Thomas Seeley's research has focused on analyzing the collective intelligence and natural lives of honey bees. This account describes how the author encountered honey bees as a boy and became a beekeeper; how he switched his career path from medicine to biology to study the behavior and social life of honey bees; and how he focuses on understanding how a honey bee colony functions when it lives in the wild, rather than in a beekeeper's hive. He has shown how a honey bee colony works as a single decision-making unit to adaptively allocate its foragers among flower patches and to choose its nesting site in a hollow tree. These findings buttress the view that, in some social insect species, the colony is a group-level vehicle of gene survival. Beyond his research, he has written three books to synthesize these findings for biologists and share these discoveries with beekeepers. Expected final online publication date for the Annual Review of Entomology, Volume 67 is January 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Honey Bee Colony Population Daily Loss Rate Forecasting and an Early Warning Method Using Temporal Convolutional Networks

The population loss rate of a honey bee colony is a critical index to verify its health condition. Forecasting models for the population loss rate of a honey bee colony can be an essential tool in honey bee health management and pave away to early warning methods in the understanding of potential abnormalities affecting a honey bee colony. This work presents a forecasting and early warning algorithm for the population daily loss rate of honey bee colonies and determining warning levels based on the predictions. Honey bee colony population daily loss rate data were obtained through embedded image systems to automatically monitor in real-time the in-and-out activity of honey bees at hive entrances. A forecasting model was trained based on temporal convolutional neural networks (TCN) to predict the following day’s population loss rate. The forecasting model was optimized by conducting feature importance analysis, feature selection, and hyperparameter optimization. A warning level determination method using an isolation forest algorithm was applied to classify the population daily loss rate as normal or abnormal. The integrated algorithm was tested on two population loss rate datasets collected from multiple honey bee colonies in a honey bee farm. The test results show that the forecasting model can achieve a weighted mean average percentage error (WMAPE) of 17.1 ± 1.6%, while the warning level determination method reached 90.0 ± 8.5% accuracy. The forecasting model developed through this study can be used to facilitate efficient management of honey bee colonies and prevent colony collapse.

Application of the Natural Products NOZEMAT HERB and NOZEMAT HERB PLUS Can Decrease Honey Bee Colonies Losses during the Winter

Honey bees (Apis mellifera L.) are crucial pollinators for many crops and natural ecosystems. However, honey bee colonies have been experiencing heavy overwinter mortality in almost all parts of the world. In the present study we have investigatеd, for the first time, the effects from the application of the herbal supplements NOZEMAT HERB® (NH) and NOZEMAT HERB PLUS® (NHP) on overwintering honey bee colony survival and on total protein and lysozyme content. To achieve this, in early autumn 2019, 45 colonies were selected and treated with these herbal supplements. The total protein and lysozyme content were evaluated after administration of NH and NHP twice the following year (June and September 2020). The obtained results have shown that both supplements have a positive effect on overwintering colony survival. Considerable enhancement in longevity of “winter bees” has been observed after the application of NHP, possibly due to the increased functionality of the immune system and antioxidant detoxification capacity. Although the mechanisms of action of NH and NHP are yet to be completely elucidated, our results suggest a new holistic approach on overwintering honey bee colony survival and welfare.

Accelerated Varroa destructor population growth in honey bee (Apis mellifera) colonies is associated with visitation from non-natal bees

A leading cause of managed honey bee colony mortality in the US, Varroa destructor populations typically exceed damaging levels in the fall. One explanation for rapid population increases is migration of mite carrying bees between colonies. Here, the degree to which bees from high and low mite donor colonies move between apiaries, and the effect visitation has on Varroa populations was monitored. More bees from low mite colonies (n = 37) were detected in receiver apiaries than bees from high mite colonies (n = 10, p < 0.001). Receiver colony Varroa population growth was associated with visitation by non-natal bees (p = 0.03), but not high mite bees alone (p = 0.19). Finally, colonies lacking robbing screens experienced faster Varroa population growth than screened neighbors (p = 0.01). Results indicate visiting non-natal bees may vector mites to receiver colonies. These results do not support the current two leading theories regarding mite immigration – the “mite bomb” theory (bees from high mite colonies emigrating to collapsing colonies), or the “robbing” theory (natal robbing bees return home with mites from collapsing colonies). Potential host-parasite effects to bee behavior, as well as important management implications both for Varroa treatment regimens and breeding Varroa resistant bees are discussed.