This project aims to increase knowledge of Australian blue-banded bees and use this to develop protocols for their large-scale rearing and deployment as pollinators in commercial greenhouses.

In the current reporting period, two PhD students have joined the project and boosted several research activities. Due to persistent La Nina weather conditions, the bee flight season started later than normal, but bee activity has been good in the field since January. This has allowed the project team to collect a considerable amount of data on the bees’ daily rhythms and foraging behaviour in field conditions, and to collect pollen samples from bees to identify what they are feeding on.  In addition, there has been good uptake of the bee bricks deployed at several field sites, with many bees using these for nesting. The flight season has now ended and the research team has brought the occupied bricks into the glasshouse where the offspring will hopefully emerge to start a captive population next spring. A subset of the bricks will be dissected to confirm presence of bee larvae and try to rear a few in Petri dishes. 

Preliminary glasshouse / greenhouse experiments have also been conducted with the bees in both Richmond NSW and Brisbane QLD. In both sites, wild-caught bees adapted to the enclosure quickly and began to visit bee forage plants such as Salvia and Duranta, as well as both crop and non-crop Solanaceae. In addition, the bees were observed to feed from an artificial sugar feeder and use the nest blocks overnight. At least one wild-caught bee was observed undertaking nesting activity in the block. 

Over the past six months, the project team have reported progress in the following areas:

• Two PhD students have been selected to join the research program.
  
  
• Due to persistent La Nina weather conditions, the bee flight season has started later than in most years, but bees have been flying since late November, and they are nesting in artificial nest blocks at some of the field sites.
  
  
• A glasshouse has been prepared to receive the bees early in 2023, but the project team will not translocate the artificial nests for a few weeks, to allow the bee larvae to develop further and more eggs to be laid. This will also allow time to take advantage of good opportunities to collect data on the foraging behaviour of these bees at known field sites over this period.
  
  
• A dataset has been compiled on blue-banded bees from records submitted to the Atlas of Living Australia. This reveals that they have been recorded visiting a wide variety of plants, with Salvias and other plants in the family Lamiaceae making up the highest percentage of records. While there are intrinsic biases in such data, there is evidence that the bees prefer flowers that appear purple, pink or white to humans, suggesting a UV component to preferences.
  
  
• This survey has been used to select 12 species / varieties of flowering plants and establish these in flower beds for further studies with the bees. The research team has also trialled a method for sampling pollen from live bees without harming them such that they can be released back into a captive population, or the wild, after pollen removal for DNA analysis.
  
  
• Finally, the team has also engaged with stakeholders through a Project Reference Group meeting, a walk-and-talk presentation on glasshouse pollination for the Protected Cropping Association, and a webinar talk and Q&A session on blue-banded bees for National Pollinator Week.

Investigations on nesting materials have begun by constructing five types of artificial nesting blocks, using different designs, housing materials and substrates. These have been deployed at 13 sites of known blue-banded bee activity in the Greater Sydney Region. While bee activity has been severely depressed in the latest spring and summer seasons due to the extreme rainfall and flooding, the project team have observed blue-banded bee activity around the artificial nests and preliminary observations suggest that the design that involves pieces of rectangular PVC pipe with tennis court loam filling is the most promising.

DNA barcoding testing is underway to characterise diets of wild-caught bees in a non-destructive way. This was achieved by taking swabs from captured adult bees using sticky tape followed by releasing the live bees.

Trials were also run to assess how adult blue-banded bees adapt to glasshouse conditions with floral resources and artificial nest sites. Results showed that the bees were active and foraged on the flowers, however, they did not survive for long or establish nests.