The MountBuzz Borneo team 2026 consisted of Andrea Errante – his third trip within the MountBuzz project now! – Julian Gericke, Isabella Fresner and Hong Chen. They were further accompanied by PAIn lab member Ben Lazarus, who introduced the team to artificial vibration experiments and single visit experiments with bees. The team was lucky in finding many species in flower, but unlucky with equipment failure. The air particle counters we use for pollen counting stopped working – despite having worked perfectly fine when tested the day before departure in the lab. The team readjusted the fieldwork plan somewhat, decided to use an alternative method for pollen collection (in Eppendorf tubes) and further refined the single visit experiments test stand! Julian in particular turned out to be a bee whisperer and just recently surpassed the 200th single bee visit, for which he also obtained accurate bee size measurements and audio recordings! Another great surprise for the team waited at one of our lower elevation sites – while in 2025, the team could only locate a single species in flower (Melastoma malabathricum), this time, they found three other species in full flower, covering tribes that we had not sampled previously! Discoveries like those show how valuable it is for us to go back to the same field sites at different times, because they might hold treasures previously unnoticed! Congratulations to the whole team for working through many challenges and keeping up the spirit!
Lalaina and Tsito from our Madagascar MountBuzz team had just finished their first year of data collection in December 2025, when starting to make plans to go back to the field in February 2026. The reason was that during the October-December fieldwork, while highly successful for finding certain genera such as Medinilla in flower, few species of the genus Gravesia flowered, and especially few at the lowest elevations. Because we need assessments of plant-pollinator interactions across the entire elevational gradient, capturing the low elevation species is equally important as capturing the high elevation species. For this reason, Lalaina and Tsito went back to the field for another month and conducted a highly successful fieldtrip, finishing pollinator observations at low elevations, with many different bee species visiting the available Gravesia flowers! They further had a chance to monitor flower and fruiting phenology, adding to the dataset collected last year, and revealing exciting patterns of stacked flowering of different Melastomataceae genera. Hiking back up to the summit further allowed them to evaluate the results of the hand pollination treatments performed by Andrea and Gregor in 2025. Lalaina and Tsito are now busy reviewing the pollinator video data collected in 2025 and 2026 to estimate flower visitation rates, as well as working on bee identifications. If all goes well, they will visit the PAIn lab at the University of Vienna later in 2026 to work on pollen counting and complete datasets for their respective PhD projects on Medinilla and Gravesia.
In late March 2026, the MountBuzz Brazil team wrapped up fieldwork in the Atlantic Forest in Eastern Brazil, where they had spent three months revisiting sites we had worked at in 2025, and scouting for a few new sites and species. Throughout the fieldwork, the team struggled with heavy rainfalls and bad weather – which also, on the other hand, led to several exciting discoveries, such as that it is literally impossible to extract pollen through mechanical vibrations from Melastomataceae anthers when it is rainy. Likely, this inability to extract pollen comes from humidity-induced clumping of pollen grains, and makes it even more understandable why bees don’t forage under these rainy conditions! This second year’s fieldwork was structured around filling small gaps in the dataset collected last year, but primarily oriented towards new experiments, particularly single-visit pollination experiments with different bees. In single visit experiments, a previously unvisited flower is made available to a single bee visit only, and then collected in order to count pollen grains deposited on the stigma, and pollen remaining in the anthers. We will compare the remaining pollen to pollen available in unvisited flowers to obtain a measure of how much pollen the bee has removed. For these experiments, we have developed a novel test stand where we fix the flower in a standardized way and connect it to a piezo-microphone with which we can measure the tissue-borne vibrations. Amongst other things, we hope to obtain reliable measurements of vibration amplitude, which generally cannot be measured accurately under field conditions. Apart from single-visit experiments, the team was also busy performing artificial vibration experiments for as many species as possible to explore how morphologically distinct species release pollen when exposed to the full spectrum of the bee-vibration parameter space. César, who led the fieldwork, is getting ready to present preliminary findings at several conferences later this year, including the 6th Pollination Biological Symposium in Brazil in August, the 13th Colombian Botanical Congress in October, and the 40th SCAPE meeting in Sweden in October! If you are going to any of these conferences, make sure you get to listen to his talk! =)
The first year of data collection has come to an end, with the PhD students César Arvelos, Andrea Errante, Lalaina Ramiliarisona and Tsito Randriatsitohaina having spent six months in the rainforests to study Melastomataceae reproductive biology. They were joined by highly movtivated field assistants and together were able to ammass an incredible dataset, covering 100 species of Melastomataceae across more than 20 genera and 12 distinct tribes. Some tribes, like Melastomateae, Miconieae and Sonerileae are represented by many species across different elevation zones in the elevational gradients! The fieldwork teams could document several novel instances of pollinator shifts in Melastomataceae, encompassing different diurnal bird and nocturnal rodent and bat pollinators! They could also document different cases of generalist insect pollination and record bee vibrations for a large diversity of different bee species visiting the whole breadth of flower morphological diversity of Melastomataceae. Currently, we are working our way through more than 10TB of pollinator video recording data, extracting sound files to characterize bee vibrational properties, identifying bee and plant taxa, counting pollen grains (from many thousands of flowers collected in Eppendorf tubes) and preparing for DNA extractions of bees and plants. Several of the plant species we found during fieldwork are new to science, and the same likely holds true for some of the bee species! Detailed species descriptions will thus also form part of our work in the next years.
While this first field season has come to an end and much of the collected samples still await processing, new field teams are forming to start data collection for the second field season. The second field season is inteded to fill small gaps in the year 1 dataset, allow digging deeper in some unresolved cases (specifically regarding the mating systems of some Melastomataceae) and implement more risky (but very fun!) pollination experiments! Updates on the next fieldtrips will follow! (photo credit: César Arvelos)
Our Malagasy PhD students Lalaina Ramiliarisona and Tsito (Richard) Randriatsitohaina had visited Mount Marojejy together with Agnes in March for an initial exploratory trip to understand species diversity, select study areas and start monitoring phenology. In July, during the Madagascar winter, Lalaina and Tsito returned to Marojejy, camping high up in the cloud forest under continuous rain and temperatures below 10 °C. Besides the unpleasant weather, they could report that none of the Melastomtaceae species we had found in March was flowering in July, a pattern we had expected, but which needed empirical verification. In early October, Lalaina and Tsito returned to Marojejy for the third time, accompanied by Andrea Errante and Gregor Traun from the University of Vienna, as well as our engaging and highly motivated local guide Ris, who counts with 20 years of experience as a research assistant in ecological and conservation projects (like lemur conservation). Fieldwork in Mount Marojejy is the most challenging because the entire gradient can only be reached by foot, there is no electricity in the field to recharge camera batteries or freeze samples and accommodation is in tents. Because Lalaina and Tsito had experienced severe rains in Marojejy before, they advised us to bring additional tarps to shelter tents, as well as a shovel to dig trenches for better water runoff. We, on our end, stocked up on rechargeable camera batteries which would be recharged whenever the team leaves the forest, and adapted the whole MountBuzz protocol to work without electricity and freezers for bee or pollen storage. Before heading to the field, the team – now experienced in the field cuisine – did a great job buying all necessary food supplies for ten days in the forest – more than 100 cups of rice, 60 cups of beans, vegetables, coffee, sugar, tea… we are lucky that local porters are ready to help in Marojejy, carrying all equipment, food, tents and personal bags up the mountain for us – they always leave hours after us, but arrive hours before us! Another big contrast – as European scientists, we are told to wear high boots and long pants and long sleeve shirts and use tons of mosquito repellent – locals walk barefoot in shorts and shirts and are just fine 🙂
When entering the forest and making our way up the mountain, the classical MountBuzz pattern seemed to haunt us – sterile or fruiting plants… this had been expected to some extent because peak flowering in Marojejy supposedly happens in November and December, but we wanted to have a head-start in case phenological patterns change (the worst a pollination biologist can find in the field are fresh fruits…). And indeed, in the higher elevation cloud forests, we were not disappointed, as several species of the beautiful genus Medinilla had already started flowering! After some exploration, we could also successfully launch the first phase of data collection for MountBuzz in Madagascar, putting up video cameras, waiting in front of flowers to catch bees, performing manual pollination experiments and monitoring of floral longevity. The pollinator observations in Madagascar will be particularly interesting because to our knowledge, there are only five pollination studies for Melastomataceae for all of Africa – with approximately 500 Melastomataceae species on the continent, and 500 on Madagascar. Given that Marojejy also is a destination for nature-enthusiastic tourists, and that Madagascar is suffering a continued high rate of deforestation, one of our project aims with Lalaina and Tsito also is to prepare little leaflets about Melastomataceae, their pollination, and the importance of plant-pollinator interactions for the maintenance of biodiversity and human well-being in both Malagasy and English, to share our results more broadly. Stay tuned for those leaflets!
steep cliffs create biodiversity gradientsrainproof?Lalaina joining the lemurs to mount a cameraour food is packed in rice bags for the porters to bring it to our campbeautiful Medinilla in flower!cloudforets have their name for a reason…arriving at the mountain campexploring the highest areas in search of flowers
In early September, the MountBuzz Ecuador team united in Ecuador, consisting of César Arvelos and Juliane Nazari-Montazer (University of Vienna), Laura Lopresti (James Cook University, Australia), and Madelén Quistial and Juan Carlos (INABIO, Ecuador). During the first weeks, the fieldwork team was joined by Diana Fernández-Fernández and Agnes Dellinger for an exploration trip to all the study sites. At first, we thought we were only going to find fruits… Diana had visited the area a few months prior (July) and found many Melastomataceae species with flowers – understanding phenological patterns still is a major challenge in tropical ecosystems, and obviously, Agnes’ observations from her PhD did not fully match up – Agnes had worked in the same area during her PhD and normally found many species in flower in the months between September and November. Eventually, however, more intense explorations paid off, and the team could locate good areas with many flowering Melastomataceae, such as in the few remnant rainforests in the Chocó. The trip to the Chocó, coming from the high Andes and cloud forests around Quito, was particularly impressive, troublesome and thought-provoking. The Chocó is one of the most biodiverse (and wettest!) areas of our planet, yet has suffered from intense deforestation, which we could unpleasantly testify when driving through barren grasslands where only about 30 years ago, there had been pristine primary rainforests. For the trip to the Chocó, we were joined by our long-term friend and colleague Pancho Sornoza, bird specialist and conservationist in Ecuador, who had been instrumental in preserving some of the remaining forest patches of the Ecuadorian Chocó. Waking up to the calls of howler monkeys and falling asleep to a tropical frog concert, getting a glimpse of ice shields of the majestic Cayambe volcano when the cloud forest clouds lifted for a moment, and watching many buzzing bees on Melastomataceae flowers certainly stick out as highlights from the exploratory trip.
After settling on the field sites, we started training and data collection in the high elevation cloud forests, and were immediately rewarded by exciting discoveries. Besides the bee-pollinated Melastomataceae, we could record new instances of pollinator shifts to vertebrate pollinators, namely hummingbirds and bats, by putting up cameras during day and nighttime. We further performed a range of manual pollination experiments to understand whether reproductive strategies of Melastomataceae change to reproductive autonomy at high elevations (where bee pollination is often limited by adverse weather conditions). At this point, also a big shout out to the Ecuador team – this type of fieldwork is all but easy, and besides harsh conditions during work in the field, living conditions may also be harsh – like sleeping in a tent on a cold stone floor at 3000 masl. The upside: a bucket-shower under the starry sky 😉
Starting our road trip to scout for study sitesexploring…and exploring…and exploring…making herbarium specimens is an essential part of our workon a bumpy ride on a road that no one thought was passableworking hard to move the car out of the mud…in every plot, we found the largest Melastomataceae genus, Miconiabeautiful Bellucia!Monolena on a waterfall cliff!our luxury campingmating system experiments in the fog…putting up cameras for pollinator monitoringprecious cloud forests!
In March 2025, we also started our work for MountBuzz on the island of Borneo, in the Malaysian state of Sabah in Northern Borneo. We – that is a team of three students from the University of Vienna (Imran Sadovic, Andrea Errante, Isadora Skudelny) together with Agnes, our collaborators from the Universiti Malaysia Sabah (botanist Florina Anthony and insect evolutionary ecologist Sze Yek Huei) and Belle Damasus, who is a Master student with Florina and working on filmy fern ecology on Mount Kinabalu. On our initial exploration trip in the first week, we were accompanied by several expert botanists from the Universiti Malaysia and from Sabah Parks, whose knowledge helped us not only to identify different Melastomataceae genera which we all saw for the first time in Borneo, but also to learn a lot about other rainforest plants and which ones can be used for medicinal purposes, or prodcue yummy fruits. Eating and cooking became a thing in the team in the course of the trip, with our Malaysian colleagues introducing vegetables and cooking techniques to the European team members that they hadn’t known about, such as the use of differnet Cucurbitaceae shoots in stir fries and soups… and vice versa, the European team members prepared a few classical central European meals, such as Gulasch (a paprika-heavy beef stew) with Spätzle (a type of pasta) or boiled potatoes with butter and salt.
Our exploratory trip featured different areas of Mount Kinabalu, including lowland foothills around Poring hotsprings (where the world’s biggest flowers, Rafflesia, grow!), mid-elevation montane rainforests with beautiful streams, and a hike into the higher elevations of Mount Kinabalu where one transitions from montane forest to cloud forests and will, eventually, reach treeline. Interestingly, Melastomataceae on Mount Kinabalu do not reach the Alpine zone above treeline, which they do on all other gradients. We do not know the reason for this difference, but it is an interesting question to ponder on in the future. Initially, we found many species just with fruits or sterile, but as always, as we kept looking and exploring more in the forest, more and more individuals with flowers and buds started showing up. The most common genera we found were Medinilla, Melastoma and Sonerila, with the latter being small herbs growing on the shaded forest floor in dense moss layers. We also found some more rare genera such as Catanthera, Astronia, Phyllagathis and Dissochaeta. At this phase of the project, any flowers we find are exciting, since almost all of these genera don’t have any information on their reproductive biology, and if they do, often only for one species from a single locality, while many genera (such as Medinilla, Melastoma and Sonerila) are actually large and geographically widespread. Again, we put up cameras for video monitoring of pollinators, backed up by direct observations and bee catching to identify bees and collect pollen samples from them. We further started manual pollination experiments to understand whether the species can reproduce in the absence of pollinators, monitor flower longevity and flower traits. The team will employ this protocol and data collection across multiple different sites in different areas of Mount Kinabalu in order to understand how reproductive strategies change across elevation.
At the end of February, Agnes travelled to Madagascar for an exploratory trip to prepare fieldwork later in 2025. In Antananarivo, the capital city, Agnes was warmly welcomed by Lalaina Ramiliarisona, our Malagasy team member and PhD student in the MountBuzz project, and Richard Randriatsitohaina, field assistant. Lalaina had done a great job in the previous months getting research permits ready and gathering as much information as possible to prepare the trip to Northern Madagascar to Marojejy National Park. Fieldwork at Marojejy is different from all other fieldsites in MountBuzz because there are no research stations, but the team will actually camp in the forest. We are very lucky, however, in that Mount Marojejy counts with a trail from almost sea level all the way to the summit, making our work along the elevational gradient a lot easier! Furthermore, there are camps established at three different elevations, and they feature basic cabins and roofed kitchen areas for preparing food and sorting specimens. And, a luxury: the first two camps are right next to beautiful rivers, which make for refreshing baths at the end of fieldwork days, while just a few meters away in the pristine primary rainforest, different lemur species forage on leaves and fruits (including from Melastomataceae!).
When we arrived, Lalaina had already made arrangements with a local guide, cook and porters who greatly helped us bring our equipment and luggage to the camps, find plants and keep us fed throughout the trip. We embarked on the first week-long journey into the forest, with many to follow in the coming months. In the course of her project, Lalaina will get to know Marojejy very well since she does not only study the Melastomataceae pollination and breeding system ecology in the frame of MountBuzz, but also will look into flowering and fruiting phenology as well as dispersal. To this end, Lalaina will return to Marojejy repeatedly over the next two years. In our exploratory trip in March 2025, our aim was to find and identify as many different Melastomataceae species as possible along the summit trail. We could locate many species of different genera, including Gravesia, Medinilla, Rousseauxia and Dichaetanthera. The genus Memecylon is notoriously hard to find since leaves don’t have the typical Melastomataceae venetation and resemble the leaves of other genera – we found some candidate individuals, but will need to wait for flowers in order to be sure. All Melastomataceae we found, we marked with bright orange tape to make it easier to relocate them on future trips, took GPS points, made herbarium collections, measured flowers and fruits and recorded the phenological state of the plants (so if they were flowering, fruiting, sterile, …). If flowers were accessible for experiments, we also placed mesh bags over buds to prevent pollination by animals – if fruits form in the bags regardless, this would tell us that the plants can actually reproduce without animal pollinators. The results of these pollinator exclusion experiments we will only have once Lalaina goes back to the field later in 2025. Well… hopefully we will have results! Although no detailed studies have been conducted, it seems like lemurs do actually forage on Melastomataceae fruits – thus, we are curious to see whether lemurs will remove the bags we placed on inflorescences to get to the juicy, sweet fruits!
Our exploratory trip was also interesting because it happened during the cyclone or rainy season of Madagascar, where usually not many botanists go to the forests. Preparing for our trip, we had been told by several colleagues that likely, we wouldn’t find any flowers because of the rainy season making it less likely for bee pollinators to be around. Our first interesting observation was that there were actually a lot of species bearing flowers, but obviously, if no biologists go to the field in the rainy season, no one knows. On the other hand, it will be very important for us to come back also in 2026, since flowering and fruiting phenologies in the tropics can be very variable and influenced by El Nino events, so multi-year data is a must. In the next months before returning to the field, Lalaina will be busy comparing the many herbarium collections we have made to existing collections in different herbaria in Antanananarivo to identify the Melastomataceae species we have found.
February has been a very busy month in project MountBuzz, with the Team Brazil continuing their fieldwork at different sites in the Atlantic Rainforest. After the high elevation sites in Itatiaia National Park, the team moved to the lowest sites at the seaside around beautiful Picinguaba to continue their work on plant-pollinator interactions and reproductive strategies of Melastomataceae. They were very successful and could find a species (Henriettea sp.) from a tribe we had not sampled yet, thereby importantly increasing our sampling across the phylogeny. Also, they managed to work with several species of Pleroma and could document very large carpenter bees on the flowers, as well as a high diversity of bee visitors on much smaller-flowered Miconia species. We all start dreaming about the pollination networks that we will be able to plot very soon after data collection and identifying the plants and pollinators we are working with. Photo credits: César Arvelos.
Also, at the end of February, Agnes travelled to Madagascar for the first time to meet local PhD student Lalaina Ramiliarisona, who will work in the MountBuzz project and collect additional data on Melastomataceae phenology and fruiting strategies. Agnes was received very warmly by her Malagasy colleagues and very much enjoyed the opportunity to interact with students from the University of Antanananarivo and the Madagascar Biodiversity Center in a lecture on Melastomataceae pollination and a workshop on the use of trait syndromes in ecology and evolution. Tomorrow, Agnes and Lalaina will head out to the field to explore the study sites for the MountBuzz project!
In early January, the Brazil team, consisting of César, Marcela, Jota and Carlos met at Sao Paulo Airport with Agnes, and together with Vini de Brito and more students from the Universidade Federal do Uberlândia, the team started scouting for suitable fieldwork sites in the Mata Atlantica. The Mata Atlantica, or Atlantic Rainforest, is a megadiverse wet rainforest on the Eastern coast of Brazil, with only fragments of the natural forest remaining at low elevations close to the popular beaches. Biogeographically, the AF is a very important region since it shows a very interesting connection to the Andean (cloud) forests, with many plant genera having closely related species both in the Andes and the AF.
We chose the AF as our first gradient for the MountBuzz project since it harbours a large diversity of Melastomataceae, and has relatively easy accessibility, perfect for a project where we want to work at different elevations and in different forest types. In the first days, we explored forests starting at the sandy beaches of Parque Estadual do Serra do Mar, and worked our way up through the mountain forests into the high elevation fields of Itatiaia National Park, Brazil’s oldest national park. Our aim is to study pollinator diversity of Melastomataceae communities, as well as reproductive strategies, flower longevity and flower traits of Melastomataceae along the gradient to understand how changes in abiotic and biotic conditions affect trait functioning. To do so, we set up the first three study plots over the past days and spend much time in the cloudy, rainy weather manually pollinating flowers. During sunny hours, we could capture bees and document their behavior. Bee pollinators of Melastomataceae exhibit a very exciting behavior called buzz-pollination, where bees vibrate flowers in order to extract pollen. We use cameras and special microphones to record these bee vibrations to better understand how bees extract pollen from flowers, and whether they vibrate different flowers differently. Besides bee-pollinated species, at high elevations, we also found species which produce nectar and are pollinated by more diverse pollinator assemblages, including wasps, flies, honeybees and hummingbirds.
Our first week of data collection was very successful, and Team Brazil will spend the next 2.5 months collecting these data along the AF elevational gradient. Stay tuned for updates!!
