Small Colonies Of Honey Bees Research Articles

Declining abundance of pollinating insects drives falls in loquat (Eriobotrya japonica) fruit yields in the Pothwar region of Pakistan

Insects perform numerous vital ecosystem services, so widespread reports of insect declines are of considerable concern. However, there are huge knowledge gaps with regard to the extent and scale of insect declines, with most studies being from Europe and North America and very few long-term data sets on insect population change in Asia, Africa or South America. The current study describes trends in abundance of insect pollinators visiting loquat (Eriobotrya japonica) over 13 years (2006–2018) in ten widely-spaced orchards in the Pothwar region of Pakistan. Results reveal a significant and concerning decline of 89.9% in overall abundance of flower-visitors across the study period. All pollinator species declined; for example numbers of Apis dorsata fell by 97%, A. mellifera by 96%, A. cerana by 93%, and Bombus haemorrhoidalis by 84%. Declines were non-linear, being most rapid in 2006–2009. In parallel, the average yield per loquat tree fell by 61%; sugar and organic acid content also declined. Total flower-visiting insect abundance was a strong predictor of crop yield and quality over time and across sites, while pollinator species richness was less powerful. Trees that were given supplemental pollination by caging them with small honeybee colonies during flowering showed no decrease in yield or fruit quality. These results indicate that declines in populations of wild pollinators are negatively impacting loquat production and the livelihood of the small farmers of the area. Further research to identify the cause of these insect declines is urgently needed, alongside development of conservation strategies for pollinators in this region.

A new, practicable and economical cage design for experimental studies on small honey bee colonies.

Bees are in decline globally as a result of multiple stressors including pests, pathogens and contaminants. The management of bees in enclosures can identify causes of decline under standardized conditions but the logistics of conducting effect studies in typical systems used across several colonies is complex and costly. This study details a practicable, new and economical cage system that effectively houses live honey bee colonies to investigate the impact of physical conditions, biological factors and environmental contaminants on honey bee health. The method has broad application for a range of effect studies concerning honey bee development, physiology, survival and population dynamics because it enables entire colonies, as opposed to individual workers, to be managed well in captivity.

A method to quantify and analyze the foraging activity of honey bees: relevance to the sublethal effects induced by systemic insecticides.

The assessment of agropharmaceuticals' side effects requires more realistic simulations of field conditions than those deduced from the dose-lethality relation obtained under laboratory conditions. Because the presence of sublethal doses or concentrations may also alter the behavior of foraging insects, we attempted to devise a quantifiable and accurate protocol for evidencing various alterations in free-flying bees. Such a protocol was illustrated by testing new classes of systemic insecticides. The protocol focused on video recording to quantify the foraging activity of small colonies of honey bees confined in insect-proof tunnels. The basis of the protocol was not the colony itself but the change in each colony on a specific day and between days. First, the paradigms of attendance at a safe feeding source were established by observing 8 control colonies at different times of the season during 5 days after the necessary forager training was accomplished. Second, on three different colonies we considered the paradigms on the control day before contamination and during 4 days after the feeding source was contaminated. During the same period, one more colony was exclusively fed with safe food to serve as control. Two plant-systemic insecticides were tested at contamination levels 70 times lower than the 50% of the lethal concentration. Imidacloprid, at 6 microg/kg, clearly induced a decrease in the proportion of active bees. Fipronil, at 2 microg/kg, induced an additional decrease in attendance at the feeder. Such levels are still higher than the corresponding lowest observable effect concentration (LOEC). Our protocol, which provided intermediate conditions between field and laboratory conditions, allowed the quantification, with an enhanced level of sensitivity, of sublethal effects on foraging bees.

The repellent effect of two pyrethroid insecticides on the honey bee*

ABSTRACT. . An improved model for the repellent effect of pyrethroid insecticides on insects was developed using small colonies of honey bees, Apis mellifera L., in flight cages. Conditioning to scented feeders allowed the separation of foraging bees from a single colony into paired treatment and control groups. The repellent response was characterized as a sublethal toxic effect resulting in transitory inhibition of activity. Permethrin and cypermethrin were shown to be contact repellents to honey bees; exposure was primarily to the tarsi and abdominal venter. Repellency was fully reversible within 24 h. No permanent effects on either memory function or foraging efficiency were observed following acute exposure.

Acephate residues after pre-blossom treatments: effects on small colonies of honey bees.

Acephate residues after pre-blossom treatments: effects on small colonies of honey bees.

EFFECT OF DIET ON THE RATE OF BROOD REARING BY NATURALLY AND INSTRUMENTALLY INSEMINATED QUEENS

SUMMARY Small colonies of honey bees were established with ca. 4,000 newly emerged Italian bees and placed in 2 x 2 x 2 m flight cages. The colonies (total of 24) were divided into two groups; twelve were headed by instrumentally inseminated queens purchased from a commercial queen breeder and twelve headed by free flight mated queens reared at Beltsville, Maryland. Each group of l2 colonies was further divided into three treatments of four colonies each. Each group was offered diets containing either Yeaco (43 ‘% protein), Wheast (58 % protein), or soybean protein (90 % protein) as the sole protein source. The amount of sealed brood reared by each colony was measured for 12 weeks. Colonies of bees fed Wheast diets and headed by either instrumentally inseminated queens or free flight mated queens reared significantly more brood than similar units of bees fed either Yeaco or soybean diets. The second greatest amount of brood was reared by bees fed Yeaco diets followed by soybean fed bees. The results of this experiment demonstrated that, overall, instrumentally inseminated queens did as well as free mated queens under controlled conditions. This study also demonstrated that bees fed poor diets regardless of the genetic background of the queens will do poorly.

Sublethal Effects of Parathion, Methyl Parathion, or Formulated Methoprene Fed to Colonies of Honey Bees 12

Small colonies of honey bees in outdoor flight cages were fed insecticide treated syrup and water for 31 days. Consumption and utilization of food and production of sugar honey, wax, and bees were measured. Even at 1000 ppm, methoprene gave no observed hormonal effects, but one formulation (Altosid R 5E) eliminated brood production. Although adult kill was not significant, bees had less sealed brood when they were given methyl parathion at 0.02 ppm or parathion at 0.1 ppm. Methyl parathion at 0.2 ppm reduced survival of adults and accumulation of sugar honey. Parathion at one ppm reduced the populations of all stages and accumulation of sugar honey. The results suggest that methoprene is relatively safe for honey bees and that parathion and methyl parathion have deleterious sublethal effects.

Modification of Chronic Bee Paralysis in Honeybee Colonies By Ribonuclease

SummarySymptoms of chronic bee paralysis (CBP) were monitored in naturally infected small honeybee colonies in flight cages. The colonies were fed sequentially either honey and then ribonuclease-free sucrose (R-FS), or R-FS and then R-FS with added ribonuclease. Each food was administered for 3–4 weeks. Both attacking behaviour and daily mortality were used as indicators of the level of CBP. Honey as treatment 1 resulted in significantly less CBP than did R-FS as treatment 1. Honey as treatment 1 also resulted in significantly less CBP than R-FS as treatment 2. When R-FS was treatment 1, the addition of ribonuclease to R-FS as treatment 2 gave a significant decrease in the level of CBP.

Honey Bee Queen Pheromones and Worker Foraging Behavior1

Small colonies of honey bees, Apis mellifera L. (Hymenoptera: Apidae), containing 600 workers were trained to collect syrup from counter-feeders in screened flight cages. Foraging activity was recorded for 2 days while all colonies had caged queens. Some queens were then replaced by porous plastic blocks containing queen extract, synthetic 9-oxodec-trans-2-enoic (9-oxodecenoic) acid, or alcohol. Foraging activity was recorded for 3 more days. Bees from colonies receiving only alcohol flew fewer trips and carried less syrup than those from colonies that received 9-oxodecenoic acid or that retained their queens. Bees receiving extract visited the feeder about as many times as those with alcohol but carried signicantly greater quantities of syrup. Death losses were greatest in colonies that received alcohol and least in those that retained their queen. Field experiments using colonies of about 10,000 workers confirmed the cage results and indicated that pollen foraging is not controlled primarily by queen pheromones as is nectar foraging. In both field and cage experiments, synthetic 9-oxodecenoic acid, at sufficiently high dosage, was an effective substitute for a queen in stimulating nectar foraging.