New Study Traces the African Carder Bee in Western Australia

Researchers from Curtin University in Perth, Australia have recorded the first known appearance of the African carder bee, Psedoanthidium (Immanthidium) repetitum, in Western Australia.

The report, published in the latest Pacific Conservation Biology, documents the first appearance of the carder bee in Western Australia. It started back in 2000 in Queensland, before experiencing a rapid increase in population on the east coast. By 2015, it was already common among urban gardens in Victoria in the southeast.

The report first noted how globalization has increased the instances of species being introduced to foreign areas.

A Rapid Expansion by the African Carder Bee

Curtin University's School of Molecular and Life Sciences' Kit Prendergast, doctorate candidate, Forrest Foundation Scholar, and lead author for the study, noted that the first documented occurrences represented a major distribution of the particular species of bee.

"So far there are three confirmed and one unconfirmed site where this species has been seen, all in residential areas of WA's Mandurah region," Prendergast said in the University's press release. She added that female specimens were taken from a garden located in the Mandurah suburb of Halls Head, a coastal residential area in Western Australia.

The African carder bee was found together with another introduced species, the European honeybee, and Australia's native bees - all foraging together.

Noting the sheer distance between Africa and Australia, Prendergast believes that the African carder bee arrived to Western Australia with assistance from humans. Adding that it was recorded in Mandurah, a coastal area and a major port, suggests that it might have arrived on the continent by boat.

Impact of Introduced Species to Local Flora and Fauna

She also added that while the carder bee's presence in WA remains rare and localized, the impact of introduced species needs to be carefully monitored. The introduction of non-endemic species has been known to create a negative effect on the local ecosystem.

Prendergast notes that while carder bees are currently "benign," they might actually be considered as "sleeper" species. Sleeper species experience a lag phase before becoming a full-blown environmental pest, hence the need for monitoring.

Unlike other species of bees, African carder bees are easily identifiable through their nests - made from hair-like plant fibers scraped by the females from plants, rolled into balls, and ultimately looking like cotton wool. Moreover, native bees in Australia create nests only for themselves. These foreign bees, however, nest communally. Brood cells from multiple females are usually found in one place.

Requests for Carder Bee Witnesses

The Curtis University press release also invites people who witness the black and white-striped bee, or its communal nests, to report to Kit Prendergast's Facebook group, "Bees in the burbs." The bees in the suburbs, or "burbs," are often found inside electrical meter boxes.

Aside from the ongoing efforts of the Curtis University's Kit Prendergast, a similar call is made by the Insect Behaviour and Ecology Lab from the University of Sydney's School of Agriculture. In their website, they shared a 2014 survey noting that it was the third most common bee species in community gardens across Sydney.

They also listed down traits to help people identify an African carder bee from others. Ranging from 5 to 8 mm, the Sydney-based initiative noted that carder bees have colored exoskeletons while other species only have colored furs.