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Menezes, C.

Publications and source records attributed to Menezes, C..

3 recordsLinked to original sources

Hive position matters: spatial layout and hive colour impact forager traffic and drifting in Melipona quadrifasciata bees

Stingless bees are key pollinators of native and cultivated plants, and their management mostly for honey and hive commercialisation has become an increasingly popular practice in Brazil. Hives are commonly kept close together and visually similar in meliponaries, a practice that favours drifting, i.e., the return of foragers to a foreign nest. Distance between hives and layout have been identified as drivers of drifting in the Western honeybee, but evidence for stingless bees, the largest group of social bees, remains scarce. Additionally, stingless beekeepers frequently associate drifting with weakened colonies, uneven honey production, worker fighting, and colony population imbalances. We investigated the effects of hive layout on foraging traffic and drifting in the stingless bee Melipona quadrifasciata. We compared forager traffic across six layouts varying in distance, colour and entrance orientation. Then, using RFID tags, we tracked drifting across three layouts with the same inter-hive distance but different designs: visually similar hives, hives with opposite entrance orientation, and hives painted with distinct colours. Forager traffic was lowest in the visually similar layout during the first two weeks of monitoring, which is consistent with greater disorientation in the absence of clear visual cues. Hive position was a key driver of drifting behaviour across all layouts, with bees from edge hives drifting considerably less than those from inner hives. Drifting decreased considerably in hives with different colours (37.6%) and hives with entrances in opposite directions (48.1%), compared to similarly looking hives with entrances in the same direction (59.5%). Therefore, our findings highlight practical low-effort strategies for stingless beekeepers to reduce forager loss, pathogen spread, and productivity losses.

animal behavior and cognition↗

A sustainable and bee-pollinated coffee to start your day

The integration of managed pollinators into agricultural systems represents a practical strategy for boosting crop production, optimising sustainable farming practices, and improving rural livelihoods. However, the use of managed bees to supplement the contribution of wild pollinators still faces challenges, such as over-reliance on pesticides in intensively managed agroecosystems. Here, we placed managed bee colonies on conventional farms to assess their impact on arabica coffee yield, quality and market value, while also to evaluate colony health in coffee fields treated with field rates of thiamethoxam-based products. We show that supplementing farms with managed bees increased farmer income by enhancing coffee yield and beverage quality, which is rewarded by specialty coffee markets. Moreover, our field-based study reveals that, even when exposed to field-realistic levels of the neonicotinoid thiamethoxam, managed bee colonies exhibited no significant adverse effects on their health within coffee fields. Our results underline that pollination is a key input on intensively managed coffee farms, and that agricultural production and environmental conservation interact synergically to maximize profitability, which is fundamental to encourage farmers to be good stewards of their croplands by adopting nature-positive practices.

ecology↗

Further evidences of an emerging stingless bee-yeast symbiosis

Symbiotic interactions between microorganisms and social insects have been described as crucial for the maintenance of these multitrophic systems, as observed for the stingless bee Scaptotrigona depilis and the yeast Zygosaccharomyces sp. The larvae of S. depilis ingest fungal filaments of Zygosaccharomyces sp. to obtain ergosterol, which is the precursor for the biosynthesis of ecdysteroids that modulate insect metamorphosis. In this work we verified that nutritional fungal symbioses also occur in other species of stingless bees. We analyzed brood cell samples from 19 species of stingless bees collected in Brazil. The osmophilic yeast Zygosaccharomyces spp. was isolated from eight bee species, namely Scaptotrigona bipuctata, S. postica, S. tubiba, Tetragona clavipes, Melipona quadrifasciata, M. fasciculata, M. bicolor and Partamona helleri. These yeasts form pseudohyphae and also accumulate ergosterol in lipid droplets, similar to the pattern observed for S. depilis. The phylogenetic analyses including various Zygosaccharomyces revealed that strains isolated from the brood cells formed a branch separated from the previously described Zygosaccharomyces species, suggesting that they are new species of this genus and reinforcing the symbiotic interaction with the host insects. ImportanceBenefits exchanged in insect-fungus mutualisms include nutrition, protection, and dispersal. Fungal nutritional roles are well described for some eusocial insects, such as fungus growing ants and termites, but similar interaction in stingless bees was so far observed just in Scaptotrigona depilis. Here we expand the knowledge of yeast-bee symbiosis by analyzing the presence, cell morphologies, lipid accumulation and phylogenetic relationships of fungi isolated from brood cells and other locations of bee colonies. Zygosaccharomyces isolates were recovered from 42% of the bee species assessed, and probably represent new species showing pseudohyphae formation and lipid accumulation similar to S. depilis associated Zygosaccharomyces strains. The phylogenetic analyses suggested an evolutionary adaptation of Zygosaccharomyces spp. to the brood cell environment to provide nutritional benefits for the developing insect. Stingless bees play important ecosystem services, and our results raise the concern that fungicidal agents used in agriculture could disrupt this symbiosis, impacting bee health.

microbiology↗