Invasive Plant Species a Boon to Bees in Fiji, Suggests New Biodiversity Opportunities

Invasive plant species can be the bane of gardeners because they encroach upon native flora, often overwhelming other plantlife. But new research on an invasive plant species in Fiji suggests that while it may be invasive, it's also beneficial to bees on the island, causing a positive ripple effect that contributes to the overall biodiversity there.

Researchers in the Suva area of Fiji examined the distribution of the bee species Braunsapis puangensis in association with the invasive creeping daisy Sphagneticola trilobata.

More than 100 types of arthropods were documented on and around the invasive creeping daisy, but the bee B. puangensis was seen to be particularly abundant.

The researchers pointed out that B. puangensis is also not native to Fiji, but probably of Indian origin and carried by humans to the islands. That a foreign bee species is thriving in an area filled with non-native plants suggests that the world's threatened honeybee colonies may be supplemented by different types of bee, the researchers said. 

"There is growing concern regarding the global decline of honey bee populations and the implications of this demise for the pollination of crops. In the future we may rely on other insect species to perform crop pollination services, including naturally-occurring native or introduced species of bees," said researcher Simon Hodge from Lincoln University in New Zealand.

"Pollination success of generalist plants tends to be positively related to pollinator diversity, so any habitat modifications that increase the number of pollinating species present at a site would tend to be of some inherent value," he said.

Hodge said the results of the study indicate that plants considered invasive may be more useful than previously believed.

"Our study suggests it is important to realize that although S. trilobata is considered an invasive 'nuisance weed' in one context, it may be of value to crop growers, and commercial honey producers, by attracting and augmenting local populations of pollinating insects," he said.

Hodge and his colleagues' research is published in the open-access Journal of Hymenoptera Research.