Skip to main content
GrowersHelp your business growResearch reports, publications, fact sheets and more Stingless bees as effective managed pollinators for Australian horticulture (PH16000)
Ongoing project

Stingless bees as effective managed pollinators for Australian horticulture (PH16000)

Key research provider: University of Western Sydney

What’s it all about?

This is a project in the Hort Frontiers Pollination Fund. It is examining Australia’s native stingless bees for their suitability as alternative pollinators to honey bees in horticulture crops.

While honey bees are excellent pollinators in many situations, their availability as both managed and wild pollinators faces various threats. This includes Varroa mite, which could lead to the collapse of wild honey bee populations if it establishes in Australia. The industry therefore needs to consider alternative pollinators, investigate their performance in different crops, and find better ways to propagate and deploy them.

The leading alternative pollinator candidates are stingless bees, which live in large colonies like honey bees, pollinate a wide variety of plants, and can be kept in managed hives. There are indeed a growing number of stingless beekeepers, and stingless bees are already used in macadamia farms. Managed stingless bees may therefore have wide but underdeveloped potential for crop pollination. Stingless bees (particularly Tetragonula species) are also used in crop pollination in several Asian countries, including in India and Thailand, so there is good scope to exchange knowledge and expertise on bee biology, husbandry and deployment in horticulture.

In looking at stingless bees, this investment is conducting studies across range of fruit and vegetable crops – testing first if the bees visit the flowers and transport the crop pollen. Where they do, the effectiveness of stingless bee pollination and its impact on crop set, yield and quality is set to be examined. For the most promising crop/bee combinations, the project team will then conduct studies of the potential of stingless bees to be effective managed pollinators in glasshouse conditions.

Trial hives for the project are established in the National Vegetable Protected Cropping Centre at Western Sydney University, which is run under this Hort Innovation Vegetable Fund project.

Specific crops involved in field work include:

  • Almond
  • Avocado
  • Lychee
  • Macadamia
  • Mango
  • Vegetable crops in both field and glasshouse conditions.

While there were some impacts due to COVID-19 restrictions, most work continued as planned with only some delays experienced due to factors such as laboratory access limitations.

Pollination in mango orchards in the Northern Territory

The team carried out extensive fieldwork on mango pollination and NT stingless bees, leading to several new findings.

As in 2019, the stingless bee T. mellipes was the most abundant mango flower visitor (56 per cent of all visits), followed by a hoverfly Mesembrius bengalensis (29 per cent). Honeybees were very rare (1 per cent). T. mellipes both carried and deposited (onto stigmas) more pollen than M. bengalensis, making it the most important pollinator overall.

Early fruit set was found to be positively correlated with stingless bee visitation rate. Research revealed about 75 wild T. mellipes colonies in bushland surrounding the orchards, showing how native vegetation supports ‘free’ pollination services. These wild bees were flying almost 500m to obtain mango pollen, suggesting potential for their use to pollinate under-visited areas of large mango blocks.

A long-term beehive design trial

Investigation of stingless bee visits to crop flowers continued, showing the bees consistently visit macadamia, using it a lot during early-to-mid flowering and less as flowering proceeds further. The team found the bees clearly prefer macadamia over avocado and will travel hundreds of metres to access it, even when avocado is much closer. Overall, stingless bees showed strong activity on lychee and macadamia, but only visited avocado well when preferred crops were absent.

In stingless beehives deployed on Lismore macadamia orchards, the researchers found that the proportion of foragers returning with pollen increases towards the end of the flowering period, but the proportion of macadamia pollen decreases. Variation in the number of foragers returning with pollen is probably correlated with variables such as hive weight, climatic conditions and brood activity, with some of these factors to be explored further.

Analysis of the effects of glasshouse ‘pollination duties’ on stingless beehive health

Previously, the team focused on the success of stingless bees in pollinating glasshouse strawberries. During this reporting period, they assessed how this pollination service affects the bees, finding that colonies of both species tested (Tetragonula carbonaria and T. hockingsi) lost weight while in the glasshouse but recovered well (to more-or-less their initial hive weight) when moved back outside with access to a wide range of foraging resources. The team are now assessing how moving hives into the glasshouse affects the bees’ gut microbiomes.

Related work showed that stingless bees are not good candidate pollinators for cucurbits, and that watermelon in open fields and polytunnels were mainly visited by honeybees and native halictid solitary bees.

A wide range of laboratory experiments and data analyses was also undertaken to obtain key results from earlier fieldwork periods.

Throughout the year, project updates were shared at events, farm visits, field days, seminars, meetings and through various publications. The team will continue to engage across industry as research progresses.

ACT NOW

Read these articles about the project’s activites and outputs:

Related levy funds
Details

This project involves the vegetable levy, in addition to other funding sources, and is funded through the Hort Frontiers Pollination Fund