A quieter week for publications, but the Asian hornet keeps advancing across Europe: a first nest has been confirmed in Poland, and a first active nest was destroyed in Apulia, southern Italy. On the research side, an Italian review traces the history of Varroa resistance to synthetic acaricides, and a Korean study uses RFID tags to test how two pesticides affect foragers' return to the hive.
In brief
- Poland: first Asian hornet nest confirmed, near Kraków; genetic tests should show how the species arrived.
- Italy: first active nest documented in Apulia, in Taranto, far from the known range.
- Varroa: a review traces the history of resistance to synthetic acaricides in Italy and calls for new studies.
- Pesticides: at the doses tested, neither fenobucarb nor carbendazim had a consistent effect on foragers returning to the hive.
Poland: first Asian hornet nest confirmed
The yellow-legged Asian hornet (Vespa velutina) has reached Poland. According to the Polish Press Agency PAP, as reported by RMF24 on 16 October 2026, a developed nest was found in Wielka Wieś, near Kraków; individual hornets were also seen at the AGH University apiary in Kraków, where no nest has been found so far. The detection started with a photo posted on the iNaturalist app, followed by photos from beekeepers; researchers from several universities confirmed the species and alerted the nature conservation services. Scientists had expected the hornet to arrive further west, in Silesia, and believe more nests exist. About a dozen specimens will be genetically tested to determine whether the hornets spread naturally or were carried by human transport. A French team specialised in nest removal is expected on site. This is based on press reports; no official statement has been published yet. See the Asian hornet page.
Source: PAP, via RMF24 (16 October 2026). Niepokojący moment. Szerszeń żółtonogi dotarł do Polski, jest pierwsze gniazdo. rmf24.pl
Italy: first active Asian hornet nest in Apulia
An Asian hornet nest was found on 27 September 2026 in San Vito, a district of Taranto, in a tree 5 to 10 metres up, close to busy areas. It was an active secondary nest containing adults and larvae. Reported through the national stopvelutina.it portal, it was fully destroyed by the Taranto fire brigade with support from the regional beekeepers’ association of Apulia (ARAP). According to the University of Salento, it is the first active nest of the species documented in the region, far south of the known Italian range. On 13 October, the university reported the find to the regional government and asked it to set up a regional surveillance task force and train beekeepers in monitoring. A single nest does not show whether the species is established locally: monitoring next spring will be needed. See the Asian hornet page.
Source: University of Salento, press release reported by Villaggio Globale (15 October 2026). Vespa velutina, a Taranto scoperto un nido attivo. vglobale.it
Varroa: the history of resistance to synthetic acaricides in Italy
Michela Bertola, Arrigo Moro and Franco Mutinelli (Istituto Zooprofilattico Sperimentale delle Venezie) have published a review of the effectiveness of synthetic acaricides against Varroa destructor and the development of resistance in Italy, the country with the longest research history on the subject. They trace how findings on resistance shaped the development and adoption of treatments, and how quickly those changes happened. Because scientific papers capture only part of the picture, they also draw on grey literature. The authors raise a concern: as climate shifts the timing of the colony cycle, synthetic compounds may become the main viable option, which makes their effectiveness all the more valuable. Yet recent studies are scarce, and the current extent of resistance is unknown. They call for new research. This is a synthesis of existing work, with no new field data. See the Varroa mites and varroosis page.
Source: Bertola M., Moro A., Mutinelli F. (2026). Effectiveness of synthetic acaricide treatments and development of resistance in Varroa destructor in Italy: historical overview and current considerations. Bulletin of Insectology, 79: 171-181. doi.org/10.3897/bull.insectology.208281
Pesticides: tracking forager homing with RFID tags
A team from South Korea’s National Institute of Agricultural Sciences (Bala Murali Krishna Vasamsetti, Kyongmi Chon, Kyeong-Hun Park and colleagues) fitted 540 foragers from three colonies with RFID tags to measure their return to the hive within 24 hours of ingesting two pesticides: fenobucarb, a carbamate insecticide, and carbendazim, a fungicide. Doses were based on residues found in pollen and bee bread, and multiplied by ten to simulate high exposure. Fenobucarb changed neither return rate, return time nor number of trips. Carbendazim lowered the return rate at the low dose (about 76% versus 92% in controls) but not at the high dose: this effect, which does not follow the dose, needs confirming. To validate the method, the authors checked that thiamethoxam clearly reduced homing. Limits: three colonies, adult foragers only, short-term effects, no effects on brood or at colony level. See the Pesticide poisoning in honey bees page.
Source: Vasamsetti B. M. K., Chon K., Kim J. et al. (2026). RFID-based assessment of sublethal effects of fenobucarb and carbendazim on honey bee homing flight. Applied Biological Chemistry, 69: 76. doi.org/10.1186/s13765-026-01145-7