What was it all about?

The project evaluated managed fly pollinators in blackberry, raspberry, blueberry, pumpkin and zucchini crops across New South Wales and Tasmania.  

Researchers tested pollination performance in cages, polytunnels and commercial field settings, studied optimal release strategies for flies, assessed pollinator activity under different weather conditions, and investigated habitat enhancements to attract and support beneficial insects. Wild pollinator surveys were also conducted to better understand the insects visiting berry and cucurbit crops.

The research found that the common drone fly (Eristalis tenax) was an effective pollinator of blackberries under commercial conditions, producing fruit comparable in size and quality to fruit pollinated through existing bee-based systems. In blueberries and raspberries, flies successfully pollinated flowers and produced commercial-grade fruit, although fruit were generally smaller than those pollinated by honeybees. The project also identified practical approaches to support fly populations through habitat improvements such as floral strips and artificial ponds.  

The work addressed concerns about pollination reliability in horticultural crops that depend on insects for fruit set and quality. Many berry and cucurbit crops rely heavily on effective pollination, while pressure on honeybee populations, including impacts from varroa mite, has increased interest in alternative and complementary pollinators. The project found that managed flies performed poorly in pumpkin and zucchini crops, indicating they are not suitable replacements for pollination in those crops. However, surveys showed native bees and other insects play important roles in cucurbit pollination, and co-flowering plants such as basil attracted beneficial pollinators.  

The findings will help growers diversify pollination strategies and reduce reliance on a single pollinator species. For berry growers, managed flies may provide the greatest benefit as a complement to honeybees because the two pollinators are active under different weather conditions. Flies remained active in cooler conditions when honeybee activity was reduced, which could improve pollination consistency and fruit quality.  

The project also produced industry articles, grower fact sheets, conference presentations, habitat management insights and practical recommendations that will support future development and adoption of fly pollination systems in Australian horticulture.