First large-scale study reveals important losses of managed honey bee and stingless bee colonies in Latin America.

Over the last quarter century, increasing honey bee colony losses motivated standardized large-scale surveys of managed honey bees (Apis mellifera), particularly in Europe and the United States. Here we present the first large-scale standardized survey of colony losses of managed honey bees and stingless bees across Latin America. Overall, 1736 beekeepers and 165 meliponiculturists participated in the 2-year survey (2016-2017 and 2017-2018). On average, 30.4% of honey bee colonies and 39.6% of stingless bee colonies were lost per year across the region. Summer losses were higher than winter losses in stingless bees (30.9% and 22.2%, respectively) but not in honey bees (18.8% and 20.6%, respectively). Colony loss increased with operation size during the summer in both honey bees and stingless bees and decreased with operation size during the winter in stingless bees. Furthermore, losses differed significantly between countries and across years for both beekeepers and meliponiculturists. Overall, winter losses of honey bee colonies in Latin America (20.6%) position this region between Europe (12.5%) and the United States (40.4%). These results highlight the magnitude of bee colony losses occurring in the region and suggest difficulties in maintaining overall colony health and economic survival for beekeepers and meliponiculturists.

Observation of Varroa destructor behavior in capped worker brood of Africanized honey bees.

The behavioral activity of Varroa destructor was observed using transparent cells. Mite oviposition started at 45.0 ± 25.0 h post capping, followed by the next eggs laid at regular 27.3 ± 2.0 h intervals. On the prepupa, mites were found to feed often and there was no preference for a specific segment as a feeding site. During the pupal stage the mite fed less often and almost always at the same point. Varroa showed a preference for defecation in the posterior part of the cell. A significant association was observed between the position of the feeding point in the pupa and the defecation site on the cell wall. Displacement behavior was observed in 71 % of the infested bee larvae and a major change in the free space available for varroa in the cell occurred when the prepupa molted into a pupa.

Behavior of varroa mites in worker brood cells of Africanized honey bees.

The ectoparasitic mite Varroa destructor is currently the most important pest of the honey bee, Apis mellifera. Because mite reproduction occurs within the sealed cell, the direct observation of varroa activity inside the cell is difficult. A video observation method using transparent polystyrol cells containing infested brood was used to analyze the behavior of varroa mites in worker brood of Africanized honey bees. We recorded how mites feed on the larva and pupa, construct a fecal accumulation site and how the bee larva carried out some longitudinal movements around the cell. The feeding activity of the foundress mite varies during the course of the cycle. On the prepupa mites were found to feed often (0.3 +/- 0.2 bouts h(-1)) for a period of 8.7 +/- 8.4 min h(-1) and there was no preference for a specific segment as feeding site. On the opposite, during the pupal stage mites fed less often (0.1 +/- 0.1 bouts h(-1)) for a period of 6.2 +/- 4.0 min h(-1) and almost always at a particular site (92.4%). On pupa, 83.7% of the feeding was on the 2nd abdominal segment (n = 92), and only few perforations were found on the thorax. Varroa shows a preference for defecation in the posterior part of the cell (cell apex), close to the bee's anal zone. We found a high correlation between the position of the feeding site on the pupa and the position of the fecal accumulation on the cell wall. Most infested cells have only one fecal accumulation site and it was the favorite resting site for the mite, where it spent 24.3 +/- 3.9 min h(-1). Longitudinal displacements were observed in 28.0% (n = 25) of the analyzed bee larvae. Turning movements around the cell, from the bottom to the top, were carried out by these larvae, mainly during the second day (47.7 +/- 22.5 min h(-1)), just before pupation, with a total time of 874.9 +/- 262.2 min day(-1) (n = 7 individuals). These results in worker brood of Africanized bees demonstrate adaptations of varroa mites to parasitizing the developing bee inside the capped brood cells.

Varroa destructor (Mesostigmata: Varroidae) in Costa Rica: population dynamics and its influence on the colony condition of Africanized honey bees (Hymenoptera: Apidae)

The development of Varroa destructor Anderson & Trueman (Mesostigmata: Varroidae) population dynamics in Africanized honey bees, Apis mellifera L. (Hymenoptera: Apidae) colonies was monitored from February to July 2004 in Atenas, Costa Rica. A correlation between the mite infestation level and the colony condition was evaluated. For each colony, infestation of varroa in adult bees was measured twice a month. Sticky boards were placed on the bottom boards of each colony to collect fallen mites. The condition of the colonies was evaluated by measuring the amount of brood and adult bees. Our results consistently showed that mite infestation on adult bees increased significantly in the experimental colonies, rising to 10.0% by the end of the experiment. In addition, the mean mite fall increased significantly over the course of the study in the treated (R= 0.72, P<0.05) and untreated colonies (R= 0.74, P<0.05) to a level of 63.8 and 73.5 mites per day, respectively. The increase in varroa infestation coincided with a decrease in the amount of brood. Furthermore, adult bees with deformed wings or even without wings crawling in front of their hive occurred in highly infested colonies (mite infestation = 10.0% or more). Rev. Biol. Trop. 56 (4): 1741-1747. Epub 2008 December 12.

La dinámica poblacional del ácaro Varroa destructor Anderson & Trueman (Mesostigmata: Varroidae) en abejas africanizadas, Apis mellifera L. (Hymenoptera: Apidae) fue monitoreada de febrero a julio 2004, en Atenas, Costa Rica. Asimismo, se analizó la relación entre el nivel de infestación de varroa y la condición de la colmena. La infestación del ácaro V. destructor fue evaluada en abejas adultas dos veces al mes. Además, se colocaron trampas adhesivas en el fondo de la colmena para recoger los ácaros que caen naturalmente. La condición de la colmena fue determinada midiendo la cantidad de cría y la población de abejas adultas. La infestación del ácaro V. destructor en abejas adultas aumentó significativamente durante el estudio hasta alcanzar un 10.0%. Igualmente, la caída natural de ácaros se incrementó, tanto en colmenas que fueron tratadas previa-mente con un acaricida químico (R= 0.72, P<0.05) como en colmenas sin tratamiento (R= 0.74, P<0.05), hasta llegar a 63.8 y 73.5 ácaros por día, respectivamente. El aumento de la infestación en las colmenas coincidió con una disminución en la cantidad de cría. La presencia de abejas adultas con alas deformes o sin alas, arrastrándose en frente de la colmena, fue observada en colmenas altamente infestadas con el ácaro de la varroa (infestación superior = 10.0%).

Varroa destructor (Mesostigmata: Varroidae) in Costa Rica: population dynamics and its influence on the colony condition of Africanized honey bees (Hymenoptera: Apidae).

The development of Varroa destructor Anderson & Trueman (Mesostigmata: Varroidae) population dynamics in Africanized honey bees, Apis mellifera L. (Hymenoptera: Apidae) colonies was monitored from February to July 2004 in Atenas, Costa Rica. A correlation between the mite infestation level and the colony condition was evaluated. For each colony, infestation of varroa in adult bees was measured twice a month. Sticky boards were placed on the bottom boards of each colony to collect fallen mites. The condition of the colonies was evaluated by measuring the amount of brood and adult bees. Our results consistently showed that mite infestation on adult bees increased significantly in the experimental colonies, rising to 10.0% by the end of the experiment. In addition, the mean mite fall increased significantly over the course of the study in the treated (R = 0.72, P < 0.05) and untreated colonies (R = 0.74, P < 0.05) to a level of 63.8 and 73.5 mites per day, respectively. The increase in varroa infestation coincided with a decrease in the amount of brood. Furthermore, adult bees with deformed wings or even without wings crawling in front of their hive occurred in highly infested colonies (mite infestation = 10.0% or more).

A comparison of the reproductive ability of Varroa destructor (Mesostigmata:Varroidae) in worker and drone brood of Africanized honey bees (Apis mellifera).

Colony infestation by the parasitic mite, Varroa destructor is one of the most serious problems for beekeeping worldwide. In order to reproduce varroa females, enter worker or drone brood shortly before the cell is sealed. To test the hypothesis that, due to the preference of mites to invade drone brood to reproduce, a high proportion of the mite reproduction should occur in drone cells, a comparative study of mite reproductive rate in worker and drone brood of Africanized honey bees (AHB) was done for 370 mites. After determining the number, developmental stage and sex of the offspring in worker cells, the foundress female mite was immediately transferred into an uninfested drone cell. Mite fertility in single infested worker and drone brood cells was 76.5 and 79.3%, respectively. There was no difference between the groups (X(2)= 0.78, P = 0.37). However, one of the most significant differences in mite reproduction was the higher percentage of mites producing viable offspring (cells that contain one live adult male and at least one adult female mite) in drone cells (38.1%) compared to worker cells (13.8%) (X(2)= 55.4, P < 0.01). Furthermore, a high level of immature offspring occurred in worker cells and not in drone cells (X(2)= 69, P < 0.01). Although no differences were found in the percentage of non-reproducing mites, more than 74% (n = 85) of the mites that did not reproduce in worker brood, produced offspring when they were transferred to drone brood.

A survey of the termite fauna (Isoptera) of an eucalypt plantation in central Brazil.

The termite fauna of a plantation of Eucaliptus urophylla S.T. Blake (Myrtales: Mytaceae) in Buritis, Minas Gerais, was manually sampled in 12 transects. The assemblage contained 28 species belonging to Termitidae and Rhinotermitidae. This assemblage corresponds to a subset of the native fauna of the cerrado previously present in this region. Compared to the original native fauna, it has a lower species richness, a much lower proportion of soil-feeders and a higher proportion of litter-feeders. A total of 1,600 recently cut trees were examined and only three (0.2%) had damage to the heartwood caused by Coptotermes sp. Despite the presence of a diverse termite fauna including several putative pest species, termites are not considered a significant problem to eucalypt plantations in this region.

A survey of the termite fauna (Isoptera) of an eucalypt plantation in central Brazil

The termite fauna of a plantation of Eucaliptus urophylla S.T. Blake (Myrtales: Mytaceae) in Buritis, Minas Gerais, was manually sampled in 12 transects. The assemblage contained 28 species belonging to Termitidae and Rhinotermitidae. This assemblage corresponds to a subset of the native fauna of the cerrado previously present in this region. Compared to the original native fauna, it has a lower species richness, a much lower proportion of soil-feeders and a higher proportion of litter-feeders. A total of 1600 recently cut trees were examined and only three (0.2 percent) had damage to the heartwood caused by Coptotermes sp. Despite the presence of a diverse termite fauna including several putative pest species, termites are not considered a significant problem to eucalypt plantations in this region.

Os cupins de uma plantação de Eucaliptus urophylla S.T. Blake (Myrtales: Mytaceae) em Buritis, MG, foram amostrados manualmente em 12 transectos. A taxocenose encontrada continha 28 especies pertencentes a Termitidae e Rhinotermitidae. Essa taxocenoce corresponde a um subconjunto da fauna nativa do cerrado anteriormente presente na mesma área. Comparada com a fauna original, ela tem riqueza menor, uma proporção muito menor de humívoros e maior de ceifadores. O exame de 1600 árvores recém-cortadas revelou que apenas três delas (0.2 por cento) apresentavam dano ao cerne causado por Coptotermes sp. Apesar da presença de uma fauna diversa incluindo várias espécies consideradas pragas, os cupins não são considerados um problema significativo nessa região.