Colonization history and population differentiation of the Puerto Rico Honey Bees
(Apis mellifera L.)
Honey bees (Apis mellifera L.) are the primary commercial pollinators across the world. The subspecies A. m. scutellata originated in Africa and was introduced to the Americas in 1956. For the last 60 years, it hybridized successfully with European subspecies, previous residents in the area. The result of this hybridization was called Africanized honey bee (AHB). AHB has spread since then, arriving to Puerto Rico (PR) in 1994. The honey bee population on the island acquired a mosaic of features from AHB or the European honey bee (EHB). AHB in Puerto Rico shows a major distinctive characteristic, docile behavior, and is called gentle Africanized honey bees (gAHB). We used 917 SNPs to examine the population structure, genetic differentiation, origin, and history of range expansion and colonization of gAHB in PR. We compared gAHB to populations that span the current distribution of A. mellifera worldwide. The gAHB population is shown to be a single population that differs genetically from the examined populations of AHB. Texas and PR groups are the closest genetically. Our results support the hypothesis that the Texas AHB population is the source of gAHB in Puerto Rico.
Honey bees in Puerto Rico: gentle bees with gentle consequences?
James D. Ackerman
James D. Ackerman1 and Nicole Martínez Llaurador1
1Universidad de Puerto Rico, San Juan, PR
Apis species are a major component of pollinator faunas in their native and introduced habitats. A widespread concern is that non-native Apis may have negative effects on native pollinators and even on plant reproduction. This is based on the assumption that natural communities are at capacity, resource competition structures communities, native pollinators are more efficient, yet Apis are superior competitors. While no studies In Puerto Rico specifically address these assumptions or the ecological and evolutionary consequences of Apis to the island’s flora and fauna, an accumulation of taxon-specific and community-level studies are suggesting that such effects run the spectrum from subtle and indirect to obvious and direct. As has been mentioned in the literature, “it’s complicated,” which begs for a concerted research effort to address the multitude of issues before us.
Long-term multiparameter assessment of the impact of Hurricane María on colony measures: A case study in gentle Africanized honey bees (gAHB) from Puerto Rico.
Jose L. Agosto-Rivera
Isada Claudio-Ford1, Jonathan Alemán Ríos1, Janpierre Alemán Ríos1, Stephanie Feliciano-Cardona1, Ashley Lozada Valcárcel1, Cheryl González1, Esteban Morales Ramos1, Giancarlo Piovanetti1, José Mayoral1, Rochelly Rivera1, Vivian Reyes1, Johann Santos-Rodríguez1, Claudia Cordero1, Edwin Rivera-Colón1, P. Arsuaga-Hernandez1, Airined Montes1, Andrés Rivera1, Courtney George1, Edwin Caraballo1, Ivan Collado1, Luis González1, Luis Santos1, Melnixa Ruiz1, Edgar Acuña2, Mehmet Ali Döke1, Remi Megret1, Tugrul Giray1 and Jose L. Agosto-Rivera1, 1Universidad de Puerto Rico, San Juan, PR, 2Universidad de Puerto Rico, Mayagüez, PR.
In September 20, 2017, Hurricane Maria hit Puerto Rico and was associated with the loss of approximately 80% of managed honey bee colonies mainly due to the winds and the posterior lack of floral resources. As part of an ongoing project, we were monitoring a colony with video at the hive entrance, photos from all frames, and various sensors measuring internal parameters (temperature, humidity and light). This effort allowed us to capture the period before and after Hurricane Maria and provided a unique opportunity to gain insight into how surviving honey bee colonies responded to this climate event. In addition, we were able to investigate whether sugar syrup and protein patties administration are sufficient to support survival, reproduction, and physiological control of the internal colony environment. Our findings indicate that despite the presence of high levels of honey from our syrup administration, and a small but stable amount of pollen stored, there was a dramatic decrease in brood one month after the Hurricane (October). We interpret this brood decrease as being caused by cannibalism since this behavior was generally observed in the apiary during this time period. Using our novel methodology to automatically detect pollen entry from videos, we found that by the 2nd month after the hurricane (November), pollen entry was recovered to pre-hurricane levels and coincided with the recovery brood levels. The protein patties feeding regimen began in this period but did not result in a further increase in brood levels. By January, which in normal years, is not a peak time of floral resources, both pollen entry and brood levels dramatically ramp-up suggesting that a shift in seasonal patterns of floral resources took place, and that honey bees follow this shift. Examining all the observations, we speculate that fresh pollen entry that fresh pollen entry, rather than pollen stored, is a key parameter for brood regulation that may serve as a key signal to either nurse or cannibalize larvae. This work was supported by the following NSF Grants: 1707355, 1633184, 1633164, 1560389, 1545803, 1736019, 1826729
The Buzz on California’s Apiary Industry and Bee Safe Program.
California is one of the agricultural leader in the U.S. with its agricultural production of more than 400 commodities representing over a third of the country’s vegetables and two-thirds of the country’s fruits and nuts. Many of these agricultural commodities rely on pollination by bees for optimal production. One of these is the $5 billion almond industry is dependent upon honey bees requiring close to three-quarters of the U.S. honey bee population for pollination, making California one of the most important apiary states.
The California Department of Food and Agriculture has implemented the Bee Safe Program to protect pollinators, primarily the European Honey Bee (Apis mellifera), and the beekeeping industry, from negative impacts caused by apiary theft, pests and diseases, lack of adequate forage, and exposure to pesticides. The Bee Safe Program directs $1.5 million annually to the County Agricultural Commissioners’ (CAC) offices, to reimburse their efforts to develop, implement, and report on activities associated with this program. CAC are granted authority identified in the Food and Agricultural Code to enforce various apiary and pest prevention laws intended to ensure the vitality of the beekeeping industry and to prevent the introduction into, or the spread within, the state of pests.
Understanding Honey Bee Viruses.
Humberto Boncristiani Freire, Jr
In the last decade an increased amount of research showed honey bee viruses playing an important role on honey bee colonies decline. Honey bee viruses can be associated with pests (Varroa/Nosema), pesticides use, bad nutrition and virtually any other components of honey bee health. Dr. Boncristiani will give an overview about honey bee virus replication, transmission, pathogenesis, and prevention, making easier to understand why theses viruses can take advantage of many different circumstances.
A Database Hosting a Collection of Data Pertinent to World Populations of Honey Bees.
The bee database and a web application to access the database have been developed as part of the collaboration between Florida International University (FIU) and University of Puerto Rico (UPR). The main functionality of the application is to collect data pertinent to bee specimens from around the world. At this stage, the database is a source of information in regards to the packages received by UPR and the samples contained in each package. Each sample comes with an assortment of information about the specimen, including but not limited to, country of origin, genus, species, subspecies, gender, caste, and so on. The database was designed taking scalability into consideration. It is capable of efficiently guaranteeing data integrity and avoiding redundancy through the normalization process. Applications built on top of the database can leverage its design to query, analyze, and manage the data in an efficient and effective way. The extensive normalization process involved in the design of the database allows the developers and administrators to effectively scale and accommodate new entities, data, and relationships. Currently, the database serves as the central repository of the data collection process and is capable of extending its current scope into more ambitious schemas, possibly integrating new types of schemas, data, queries, and operations.
Honey bee viruses, evolution and interaction with other stressors.
More than 30 viruses can infect honeybee colonies. The Deformed wing virus (DWV) has been shown to be related to colony losses, and co-exposure to other stress factors is suspected to severely weaken honey bees, altering both survival and behavioral performances. Because viral strains may not have the same virulence, we first investigated virus genetic diversity and evolution. More, we evaluated their putative role in host/vector/virus co-evolution for resistance to varroa. Then we assessed the thermal responses of the host-pathogen system to better understand their dynamics in changing environments. High temperatures significantly decreased DWV titers close to the initial viral load at emergence but increased bee mortality. We also investigated the impact of a virus/pesticide co-exposure, both in experimental conditions and in natural conditions, by inoculating newly emerged bees with CBPV and DWV and exposing them to field-relevant doses of a neonicotinoid. Co-exposure caused an increase in CBPV loads up to viral levels related to overt infections. Combined exposure to DWV and thiamethoxam did not result in higher DWV loads compared to bees exposed to DWV alone, but induced precocious foraging, increased the risk of not returning to the hive after the first exit, and decreased survival. These studies underline that viral infections have to be considered not alone but in combination with other stressors.
European and Africanized honey bees share a key adaptation to survive dearth: increased longevity.
Mehmet Ali Doke
Currently, honey bees live on every continent except Antarctica. However, the species has originated in lower latitudes and they later radiated to higher latitudes and experienced temperate winters where the main stressors are cold and lack of foraging resources. In winter, honey bees halt or severely limit brood production and worker bees live up to four times longer than their siblings in spring months.
There are two possible evolutionary histories for the change in longevity in this species: 1) flexible longevity was favored by positive selection while the populations radiated into the temperate zones or 2) some of the traits that had existed in honey bees to cope with environmental stressors other than winter were coopted during the species’ radiation – thus, acting as preadaptations.
Despite relatively stable temperatures, PR has strong seasonal differences based on flower phenology which creates a similar stressor to temperate regions where forage resources are abundant in one part of the year and heavily reduced in the other. This decoupling of resource availability and cold stress makes PR an excellent location to test whether increased worker longevity is a winter-specific adaptation or a more generalized response to seasonal dearth.
Impact of population-wide disturbances: honey bees in Puerto Rico after Hurricane María.
Donthu Ravi kiran
The honey bees of Puerto Rico are a distinct Africanized population. In Puerto Rico these “killer” bees lost their aggressive behavior while retaining Africanized characteristics such as resistance to ectoparasites (e.g. Varroa mites), and small size. Our goal is to determine whether the loss of aggressive behavior is due to anthropogenic factors and/or population-wide disturbances that are common in islands such as Puerto Rico. These forces can lead to direct selection of certain genotypes or random elimination of individual honey bee colonies resulting in genetic drift. To assess the possible role of population-wide disturbances, we sequenced individual honey bees, using BGISEQ at 30X coverage, collected prior and post hurricane María. We identified single nucleotide polymorphisms (SNPs) in the two sets of samples after aligning the reads against the European honey bee reference genome sequence. Using the SNP genotypes, we performed principle component analysis and calculated Fst values between the two groups of samples. Manhattan plots were generated using Fst values distributed across the reference genome. We identified SNPs with the highest Fst values and their specific location on honey bee chromosomes. Genes that overlap with these SNPs are considered as candidate genes under selection.
Developing a stock certification program for the Puerto Rican honey bee
Western honey bees (Apis mellifera L.) in Puerto Rico (PR) are likely descended from Africanized honey bees (A.m. scutellata hybrids: AHBs) introduced from the U.S. mainland. The AHBs in PR are said to be gentle (gAHBs), unlike their mainland counterparts, and tolerant to several pests and diseases. Consequently, the PR gAHBs could be of practical value to beekeepers trying to manage bees during a time of high pest/disease pressures and high gross loss rates of managed colonies. This has led to discussions on exporting responsibilities for PR beekeepers/scientists and importation requirements that may be levied by states composing the U.S. mainland. Subsequently, this discussion has expanded to include export/import requirements for all U.S. states and territories intending to export live honey bees (queens, colonies, package bees, etc.) to the U.S. mainland. Many states have specific requirements regarding the importation of live bees, requirements that may otherwise prohibit importation of a bee such as the PR gAHB. Accordingly, various state and federal U.S. agencies are interested in developing rules for stock certification programs and exportation requirements for live bees exported by U.S. states and territories to the U.S. mainland. The development of a stock certification program for PR gAHBs could serve as a model for other U.S. states and territories intending to export live honey bees to the U.S. mainland.
Diseases, vectors, and bee health.
Jay D. Evans
Honey bees play key roles in agriculture and are a model species for understanding social behavior and disease dynamics. Honey bee colony losses have been especially high in recent years, in part due to heavy pressure from parasites and pathogens. Of these, Varroa mites and their associated viruses are especially important. DWV strains differ in virulence and undergo complex interactions with each other and with host defenses. I will discuss approaches including modern sequencing techniques and a recently developed reverse-genetic system for DWV to 1) establish strain virulence, 2) directly measure host defenses and virus counter defenses and 3) determine whether specific viral strains act to limit the impacts of more virulent strains. I will also discuss metagenomic approaches for identifying novel and known pathogens.
Pollination and breeding system of Guaiacum sanctum (Zygophyllaceae), in two Caribbean islands.
Jose J. Fumero-Caban
Jose J. Fumero-Caban2,3,5,6 and Elvia Melendez-Ackerman3,4
2Department of Biology, College of Natural Sciences, University of Puerto Rico, Rio Piedras Campus, PO Box 23360, San Juan, P.R. 00931; 3Center for Applied Tropical Ecology and Conservation, College of Natural Sciences, University of Puerto Rico-Rio Piedras, P.O. Box 70377, San Juan, Puerto Rico 00936-8377; 5Department of Environmental Sciences, College of Natural Sciences, University of Puerto Rico, Rio Piedras Campus, PO Box 70377, San Juan, P.R. 00936; Present address, Escuela de Ciencias, Tecnología y Ambiente, Universidad Ana G. Méndez, PO Box 21150, San Juan PR 00928-1150.
A long-standing hypothesis about insular pollination systems suggests that plant species on islands are more likely to exhibit reproductive mechanisms that allow for self-compatibility or self-fertilization. We documented various aspects of the reproductive ecology of Guaiacum sanctum a highly valuable timber species of dry Neotropical forests in two Caribbean dry forest reserves (Mona Island and Guánica Forest) in Puerto Rico. We evaluated the diversity of floral visitors, visitation rates, the plant’s breeding system, and the relative success of self vs. cross-pollinations using field observations and hand-pollination experiments. Flowers were pollinated by insects, with the diversity of flower visitors being higher in Mona Island than in Guánica where honeybees were the most abundant pollinators. However, visitation rates to flowers were significantly higher in Guánica. Flowers were not apomictic and autogamy rates were negligible suggesting that insect visits are required for flowers to set fruits. Artificial cross-pollinations produced twice the fruits and twice the seeds produced by artificial self-pollinations. These differences were consistent between populations suggesting that G. sanctum is partially self-incompatible. Seed germination was higher from cross-pollinated seed but only in Guanica suggesting that inbreeding depression is stronger in Guánica than in Mona Island. Honeybee behavior might increase the rates of self-pollinations which may override any increase in visit rates experienced by Guánica trees. We argue that even when reproductive success is equivalent between populations, the Guanica site may be more vulnerable to catastrophic phenomena that may influence pollinator abundance given the smaller diversity of pollinators.
Climate and landscape influence infestation of Apis mellifera males by Varroa destructor in drone congregation areas.
Galindo-Cardona, A.1,2*, Scannapieco, A.1,3, Escalante K.4, Geria M.4, Lepori N.4, Ayup MM.1,4,5, Russo R.3, Muntaabski, I.1,3, Liendo MC.1,3, Landi L.6, Giray T.7, Monmany-Garzia AC.5 1Consejo Nacional de Investigaciones Científicas y Técnicas, CONICET. 2Fundación Miguel Lillo, FML. 3Instituto de Genética, INTA-Castelar. 4Facultad de Ciencias Naturales, Universidad Nacional de Tucumán, UNT. 5Instituto de Ecología Regional, IER. UNT-CONICET. 6Instituto de Recursos Biológicos, INTA Castelar.7Departamento de Biología, Universidad de Puerto Rico
Apis mellifera reproduction system involves drones and virgin queens that mate up in the air in sites called drone congregation areas (DCAs). Bees' parasites, such as Varroa destructor can also be present in the DCAs, causing infestation and subsequent impact on the health of the colonies. The objectives of this study were: 1. to locate DCAs in two eco-climatic regions of Argentina (Buenos Aires (BA): temperate, and Tucumán (TU): subtropical), 2. to determine the genetic variability of the drones at those DCAs, 3. to quantify parasitism by the mite in the surrounding colonies and in the DCAs, and 4. to identify the environmental variables that were more related to percent Varroa at the DCAs (i.e. climate, topography, landscape, hive management). We found 11 DCA in total in 2017 and 2018. The average distance of the DCA to the nearest apiary was 500 m. In the apiaries’ of both regions we detected only European lineages (C1, C2J). In the ACZ we found European (C1, C2J) and Africanized (A1, A2) lineages. In the apiaries, infestation with Varroa was 1.90% in TU and 1.14% in BA. In the DCAs, infestation with Varroa was 2.7% in TU and 0.7% in BA. We report the relative contribution of environmental variables to percent parasitism at the DCAs. Our results provide valuable information on an understudied component of bees’ reproduction and health, on the dynamics of a lethal cosmopolitan mite, and on bees' genetic variability.
SNP honey bee diagnostic panel.
The population of honey bees on Puerto Rico (PR) is less aggressive than Africanized Honey bees (AHB) and is exposed to fewer infectious agents than its counterpart on the U.S. mainland. To support the effort of developing a certification program for the exportation of the honey bees of PR we developed a diagnostic single nucleotide polymorphism (SNP) assay that can unambiguously identify PR honey bees. Honey bee SNP genotype data from populations originating from North and Central America, Europe and African countries were used to perform discriminant analysis on principal components (DAPC) to determine population specific diagnostic SNP markers. DAPC was repeated multiple times with iteratively fewer number of SNPs until the fewest number of SNPs that differentiated all the populations were identified. This process yielded 134 final diagnostic SNPs. Using these SNPs an Agena MassARRAY SNP assay was developed. This panel was tested using 834 samples from 21 countries (Argentina, Bolivia, Costa Rica, France, Israel, Italy, Kenya, Madagascar, Malta, Mexico, Morocco, Panama, Portugal, Georgia, Seychelles, South Africa, Spain, Tunisia, Turkey, U.S. and Zambia) as well as 163 samples from PR. Of all the samples tested, 92% matched their predicted assignation.
Colonization, Impact and Control of Africanized Honey Bees in Mexico.
Mexico is the world’s sixth largest honey producing country and the third exporter of honey. Africanized honey bees (AHBs) colonized and intermixed with exiting populations of European bees in Mexico in less than 10 years. This process took place between 1986 and 1996. By 1996, honey production, exports and yields per hive had decreased by 35, 45 and 25%, respectively. Between 2006 and 2016, thirty years after the Africanization process started, honey production, exports and yields per hive rebounded and remained stable during that decade, but are still lower than before the Africanization process, by 25, 40 and 20%, respectively. The number of colonies initially decreased from 2.2 to 1.8 million hives but by 2016 the number of managed hives was 2 million. Clearly, AHBs affected the productivity of the Mexican beekeeping industry, but the degree of damage was lower than initially expected. On the positive side, the presence of AHBs in Mexico stimulated queen production. The number of queens reared tripled in 30 years and many queen producers breed for gentleness and honey production. Additionally, a new generation of beekeepers emerged and learned how to manage AHBs with new techniques, which allows them to make them profitable.
A Reference Genome of the Puerto Rico Gentle Honey Bee.
Using Oxford Nanopore MinIon long read sequencing technology, we have sequenced and assembled Puerto Rico gentle honey bee genome. From two flowcells, we generated 28Gbps sequence data with longest sequence read at 165kbps and N50 read length at 30kbps. The long reads were assembled using Canu version 1.8 and the assembled genome has a total length of 234 Mbps in 150 contigs with the longest contig at 13.782Mbps, N50 contig length at 11.028MBps and 10 contigs above N50 length. Initial Comparison of the assembled genome to the published European honey bee Apis mellifera genome (HAv3.1) show a similar overall genome structure, though several structural variation are also obvious (inversion, translocation, etc). We are in the process of polishing the genome with illumina short reads and hope in the near future to have a high quality reference genome for the Puerto Rico gentle honey bee and provide a genomic resource for understanding their evolution and behavior
Transportation sensitizes honey bees to insecticides.
Shudong Luoa,b, Zachary Y. Huang,b
a Institute of Apicultural Research, Chinese Academy of Agricultural Sciences, Beijing, 100093. b Department of Entomology, Michigan State University, East Lansing, MI 48824
Honey bees are critical pollinators whose managed populations face global declines due, in part, to an increased use of insecticides. Transportation of honey bees is necessary all over the world to meet the demands of fruit and vegetable pollination. Previous studies have shown that transportation can affect honey bee physiology adversely but it is not clear whether sensitivities to pesticides change in transported bees.
We hypothesize that transportation weakens honey bees such that they are more prone to insecticide poisoning. Our results showed that transportation and mock transportation both sensitize honey bees to insecticides, including imidacloprid and thiamethoxam. We then tested whether this is because transportation makes bees age faster and that older bees are more sensitive to insecticides. Indeed, significantly higher juvenile hormone titers were found in mock transported bees than that in control bee and older bees are more sensitive to pesticides. These results suggest that the mechanisms of sensitization are due to transportation making bees age faster and aged bees being more vulnerable to insecticides. Thus the widely-practiced transportation of honey bee colonies sensitizes them to insecticides, increasing their risk of pesticide poisoning. Further studies are needed to provide measures to counter these effects.
Genetic structure – geography relations of honeybee subspecies in Turkey:
A survey and a test of niche overlap.
Mert Kükrer1, Ayşe Turak2, Can Bilgin1
1Department of Biology, Middle East Technical University, Ankara, Turkey.
2Nature Conservation Center, Ankara, Turkey.
Subspecies or “geographic races” of honeybees (Apis mellifera) differ in morphology, biogeography and behavior and appear to have diversified following reproductive isolation during the Pleistocene glaciation. Habitat-specific features such as daily temperature, abundance and phenology of nectar flow, length and severity of winter, or predator pressure are expected to influence morphology, foraging strategy, honey storage, production of young, overwintering success, swarming behavior or aggression in different races. We surveyed potentially adaptive behavioral traits for each genetic component identified by microsatellite-based STRUCTURE analysis, and explored relations with climatic conditions prevalent where those components are geographically concentrated. We used ecological niche modeling by MAXENT to estimate distributional ranges and identify possible climatic drivers of adaptation for four subspecies and one ecotype.
Niche modeling produced ranges for each subspecies/ecotype that roughly correspond with particular ecoregions in Turkey. A comparison of niches, predicted ecological divergence between honeybee subspecies. Hybridization between C and O lineages where niche models overlapped was confirmed with genetic evidence. No models produced were found to be covering the range of another O-lineage subspecies in Eastern Anatolia not included in this study. Relationship between an ecotype in Aegean coast and a scale insect (Marchalina hellenica) of East Mediterranean Pine (Pinus brutia) that provides an annual cycle of resource availability impact on life history of that ecotype was also concordant with its distribution models and observed distribution of both the pine and the scale insect. We discuss adaptive values of the traits of honeybees and suggest hypotheses to test these associations at the genome level.
Honey bee biting behavior as a defense against Varroa destructor.
Hongmei Li-Byarlay1,2 and Jada Smith 2
The honeybees are the most important managed pollinator for plant health, production, plant products, and sustainable agriculture. Among all the biotic stressors, a parasitic mite Varroa destructor has become a major contributor to the demise of bee colonies worldwide. Our new research program at Central State University is focusing on selecting mite biting behavior of honeybees. The central hypothesis is that the feral colonies and mite biting colonies are more mite resistant than commercial colonies by 1) displaying higher rate of mite biting behavior and defense against the mites, and 2) different shapes of mandibles. We have surveyed mite biting behavior by collecting mites from the field and score the mite biting behavior under the microscope. We have scanned pairs of mandibles using an advanced microCT scanner and detected morphological different in their 3-D shapes. Our results showed the first scientific evidence of the mite biting behavior in Ohio feral bee population, and its potential defensive mechanism using bee mandibles. Our results will provide a significant knowledge in the breeding of mite resistant bees.
Video analysis and machine learning for large-scale monitoring of the foraging behavior of tagged and untagged honey bees.
The ability to automatize the analysis of video for monitoring animals and insects is of great interest for behavior science, ecology and agriculture. Due to the high number of interacting factors to explain behavior, a multi-faceted analysis is required. In this presentation, we report the development of a new system for the detection, localization and tracking of honeybee from video on the entrance ramp of the colony. The proposed system builds on the recent advances in Convolutional Neural Networks to detect honeybee body parts with high precision and high velocity. This can be used to analyze the foraging behavior for both bees tagged with a unique barcode identifier, as well as counting all untagged bees and whether they bring pollen. These models are currently being applied to analyze weeks of videos in the context of NSF BigData project “Large-scale multi-parameter analysis of honeybee behavior in their natural habitat” at University of Puerto Rico (UPR). The results can be visualized and analyzed in a Web application we developed and that is currently deployed at the UPR High-Performance Computing facility (HPCf) to study the individual variations of behavior of honeybees.
Spying on bees: Analysis of continuous data from bee colonies.
As continuously monitoring pulse, respiration, blood pressure and other variables is becoming commonplace for humans, so it is for honey bees. Monitoring physical variables, including weight, temperature, respiratory gases, sound, and forager traffic, is becoming feasible for most honey bee researchers as cost and size of sensors decrease while their precision and capacity increase. This approach to gathering data on colony-level behavior is logical because obtaining data from sensors reduces or eliminates colony disturbance, and provides new kinds of information about colony health and activity. These points will be illustrated with data from recent field and laboratory experiments involving the exposure of bee colonies to sublethal pesticide doses.
Evaluating insect diversity of mango flowers at the Juan Diaz Experimental Station, Puerto Rico.
Elvia Melendez-Ackerman and Irma Cabrera Asencio
Mangifera indica is a widespread economically important tropical fruit. In Puerto Rico, is one of the most important fruit crops in production and extent of cultivation second only to citrus. An ongoing study at the Juana Diaz Experimental Station in Puerto Rico aims at understanding the factors that influence local pollination success and fruit yields in four mango varieties (Keitt, Kent, Tommy Atkins, Julie) at different temporal scales. We describe the ongoing study and present preliminary results of insect collection campaigns that evaluated flower visitor communities of two of those varieties (Tommy Atkins and Julie) in the spring seasons of 2017 (before Hurricane Maria) and 2018 (after Hurricane Maria). Results show clear changes in the profiles of potential pollinators and are consistent with studies elsewhere in the wide diversity of pollinators that visit mango flowers. Management implications of our findings are discussed.
Antibiotics is hives: Effects on honey bee development.
Recurrent honey bee losses make it critical to understand the impact of human interventions, such as antibiotics use in apiculture. We studied the effect of antibiotics on the bee microbiota, metabolism, and behavior throughout development. We found that core microbiota diversity was similar during development, but composition varied and clustered based on development stage; early vs. late development. Antibiotic treatment reduced microbiota diversity and numbers (“ablation”) and doubled bee adiposity. The timing of antibiotic ablation, at adult or larval stages, and “rescue” by exposure to typical colony conditions or microbiota had distinct consequences for the age of onset of behaviors such as cleaning, nursing and foraging. Behavioral development in honey bees is typically under endocrine regulation, we show genetic expression data of how development and behavioral associated genes changes due to antibiotic exposure. The effects were shared across the two commercial beekeeping antibiotics tested. We conclude that the bee microbiota has an integral role in endocrine regulation of host metabolism and behavioral development, one that seems to be affected by current use of antibiotics.
Honey Bee Genetics and Breeding in Turkey
Honeybee diseases and pests have become resistant to the commonly used and previously effective chemical treatments. Different studies have shown that honeybees have genetically determined mechanisms for disease and varroa mite resistance such as hygienic behavior. The effectiveness of hygienic behavior against American foulbrood disease depends on infected pupae being removed before the infectious stage of the bacteria, definitely before sporulation ensues at 10–11 days after egg-hatching. we aim for genetic improvement in Muğla Honeybee (Apis mellifera anatoliaca) resistance to American foulbrood diseases.
In our study 200 Mugla bee (A. m. anatoliaca) colonies collected from Mugla province. Colonies were identified with genetic methods. The position of Muğla bees of the study among 250 honeybee colonies from 18 provinces of Turkey was determined by making use of 30 microsatellite markers. Colonies evaluated 2 times for hygienic behavior in April each year. The colonies showing hygienic behavior over %95 in at least two measurements were selected and used as breeder colonies for queen production. Daughter queens were instrumentally inseminated with 10 µl of semen from randomly collected drones from the whole population. We used the “Closed Population” breeding program. Hygienic behavior increased in the population after 3 years of selection on queens with mating control (instrumental insemination). Hygienic behavior ratio was significantly different among years. High heritability was observed between 2 periods.
Amitraz resistance in Varroa mites and considerations for miticide resistance management.
The Varroa mite, Varroa destructor, is the major causes of honey bee colony losses. Most beekeepers manage Varroa populations with in hive miticides. Overreliance on these materials may result in resistance. Amitraz is the most widely used miticide to effectively control Varroa populations, but reports of reduced effectiveness are a critical issue. This research seeks to establish baseline bioassay data on amitraz sensitivity in Varroa, evaluate the effectiveness of amitraz in cage exposures, and identify management factors that may induce amitraz resistance in Varroa. Preliminary tests in the spring identified low to moderate levels of amitraz resistance in commercial beekeeping operations. Varroa were sampled from commercial beekeeping operations in New York and South Dakota in July and August 2019. While these data are forthcoming, it is anticipated that operations that use a long history of amitraz use and those that apply amitraz more than once a year will have higher levels of amitraz resistance and reduced field efficacy. These data will be important for disrupting the selective pressures that lead to amitraz resistance and Varroa control failures. It is critical to extend the utility of amitraz as few novel control materials are expected to be available in the immediate future.
Plant invasions on Caribbean islands: the role of habitat and species traits.
A fundamental goal in invasion ecology is to identify the factors explaining why some alien species become invasive while others fail. When naturalized species become invasive, their level of invasion depends on features of the invaded community, propagule pressure, and climate. In this talk, I will discuss the relative importance of factors such as introduction history, invasive status, habitat preferences, and biological and ecological species traits on driving invasion success and invasion patterns at different scales on Caribbean islands. I will use a comprehensive regional dataset of >1,000 alien plant species to address the following questions: (1) Which alien species are becoming invasive on Caribbean islands? (2) What are the species and habitat traits contributing the most to the invasion success of alien plants on these islands? (3) Is there a correlation between geographical, ecological, and socioeconomic factors with invasion? I will conclude by stressing the urgent need to implement more effective prevention policies at all scales and to perform more studies evaluating the impact of invasive species on the region as well as recommendations for their control and management.
Parasite-host interactions between the Varroa mite and the honey bee from Argentina: an approximation to grooming behavior.
Russo RM1; Muntaabski I1,2; Liendo MC1,2; Landi L 3; Merke J4; Pietronave H5; Fain H5; Galindo-Cardona A6; Lanzavecchia SB1; Scannapieco AC1,2.
1Instituto de Genética Ewald A. Favret, INTA, Buenos Aires, Argentina. 2Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina. 3Instituto de Recursos Biológicos, INTA, Buenos Aires, Argentina. 4Estación Experimental Agropecuaria Rafaela, INTA, Santa Fe, Argentina. 5Estación Experimental Agropecuaria Reconquista, INTA, Santa Fe, Argentina. 6Fundación Miguel Lillo, FML, Tucumán, Argentina.
Varroa destructor is associated with high winter mortality of Apis mellifera colonies in the Americas. One mechanism limiting Varroa population growth in colonies is the ability of some honey bees to groom mites from their bodies. In Argentina, a stock of honey bees from a subtropical region has been obtained after several years of survival without acaricide treatment. In order to explore the contribution of grooming behavior to Varroa-tolerance, we compared two lines (M, mite-tolerant vs C, susceptible). Eleven colonies from each line were evaluated for two consecutive seasons. The number of colonies that survived the winter season was higher in M than in C lines. The dynamics of Varroa infestation were similar between lines, but M maintained the mite loads at lower level. M showed a higher proportion of fallen and damaged mites than C lines through the season. Our results suggest that grooming behavior could explain the difference in Varroa-tolerance between M and C lines, by regulating the mite loads prior to the exponential mite population grown. The level of the fallen mites appears to be a good predictor of grooming and could be used as a selection target of programs breeding for Varroa tolerant honey bees.