Inventive nesting behaviour in the keyhole wasp Pachodynerus nasidens Latreille (Hymenoptera: Vespidae) in Australia, and the risk to aviation safety

Abstract

The keyhole wasp (Pachodynerus nasidens Latreille 1812), a mud-nesting wasp native to South and Central America and the Caribbean, is a relatively recent (2010) arrival in Australia. In its native range it is known to use man-made cavities to construct nests. A series of serious safety incidents Brisbane Airport related to the obstruction of vital airspeed measuring pitot probes on aircraft possibly caused by mud-nesting wasps, prompted an assessment of risk. An experiment was designed to determine the species responsible, the types of aircraft most affected, the seasonal pattern of potential risk and the spatial distribution of risk on the airport. A series of replica pitot probes were constructed using 3D-printing technology, representing aircraft with high numbers of movements (landings and take-offs), and mounted at four locations at the airport. Probes were monitored for 39 months. Probes blocked by mud nesting wasps were retrieved and incubated in mesh bags. Emerging wasps were identified to species. Results show that all nests in probes were made by P. nasidens, and peak nesting occurs in the summer months. Nesting success (as proportion of nests with live adult emergents) was optimal between 24 and 31°C and that probes with apertures of more than 3 mm diameter are preferred. Not all areas on the airport are affected equally, with the majority of nests constructed in one area. The proportion of grassed areas within 1000 m of probes was a significant predictor of nesting, and probe volume may determine the sex of emerging wasps.

Nesting of the keyhole wasp Pachodynerus nasidens (Latreille, 1812) (Vespidae, Eumeninae) in a nest of a paper wasp (Vespidae, Polistinae)

“…Pachodynerus nasidens nesting peaks occur in months of higher temperature and humidity throughout the year (House et al 2020). The ideal temperature for egg development ranges from 26 to 31 °C (Jayasing and Taffe 1982), while higher humidity ensures the availability of water and mud for nest building (Freeman and Jayasingh 1975), explaining our record in the hot and humid season.…”

“…Nests completely built by P. nasidens are rare. This species commonly acts as an inquiline, in cavities made by humans (House et al 2020) or in abandoned nests of other hymenopterans (Freeman and Jayasingh 1975;Matthews and González 2004). P. nasidens also build mud structures in the ground and fixed to plants (Carpenter 1986).…”

Evidence for Range Expansion and Origins of an Invasive Hornet Vespa bicolor (Hymenoptera, Vespidae) in Taiwan, with Notes on Its Natural Status

“…Biological invasions often cause improper affection to the natural ecological environment, such as the decline of biodiversity or deterioration of ecosystem functions [45][46][47], threat to the native flora [48], and threat to agricultural and urban environments [49][50][51], and the levels involved can also harm the human and social systems [52]. Additionally, they posed a risk to aviation safety in Australia recently [53]. Due to multiple factors, hornet has become an invasive alien species (IAS), not only causing harm to the ecological environment, but also bringing a lot of challenges to human society, economy, and agricultural production safety.…”

A Key to the Pacific Genera of Eumeninae (Hymenoptera: Vespidae)

“…This is an American genus consisting of nearly 50 species; the so-called keyhole wasp, Pachodynerus nasidens (Latreille), has been introduced on islands all over the Pacific (e.g., Krombein, 1949;Yamane et al, 1996;Gusenleitner, 2011), thanks to its indiscriminate choice of preexisting cavities as nesting sites. At Brisbane airport these nesting habits now present an aviation hazard (House et al, 2020a(House et al, , 2020b)! Type species: Alastor tuberculatus de Saussure, 1853, by subsequent designation of van der Vecht, 1967: 31;confirmed by Opinion 893 (ICZN, 1970).…”