In preparation for spring, you can make nest sites for native cavity nesting solitary bees for your garden. Get a block of timber (that has not been treated with any chemicals!) and drill some holes in it. Holes of 6mm and 8mm diameter seem to be good, and will attract resin bees and leafcutter bees. But why not experiment too? Drill some other random sizes and see what you get? Drill as deep as you can, up to a depth of about 13–15cm for the larger diametres. The holes should be angled slightly up, so the bee goes up a very slight incline as it crawls in. After drilling the holes, it can also help to flame the hole entrances slightly. One way of doing this is to briefly pass the timber over a burning gas cooking ring. I suggest just having a series of small nest blocks scattered around, rather than a big block or a ‘bee wall’, as large aggregations can increase the incidence of pests and disease. Put your nest block outside in a place where it is protected from rain and harsh summer sun. Now wait patiently, and when it starts to warm up, females of various solitary bee species might move in. If you miss seeing the bees coming and going, you will know when someone has nested in a hole because the end will be sealed up. Remember that solitary bees can sting, but usually only if handled. In nature these bee species often nest in the holes left by wood boring beetles.
Heard of the night parrot? I bet you have. What about night bees?? Yes, there are nocturnal and crepuscular (fly at dawn and dusk) bees!! And yes, they collect pollen and nectar and do the things that day-flying (diurnal) bees do. But in the dark! All bees have three little spherical structures on their heads called ocelli, which are like little extra eyes that help them see and orientate. Compared with day bees though, night bees have much larger ocelli, relative to their head size, which is one of the traits that enable them to fly in low light. In the photos below are one nocturnal bee (Megalopta centralis) and one crepuscular bee (Rhinetula dentrictus) from Panama. These I encountered while light trapping in rainforests there. They were attracted to light just like moths. Here in Australia we have one bee species, Reepenia bituberculata (QLD), which is believed to be a night flyer? It has enlarged ocelli, but no one has actually observed it flying at night. Elusive? The elusive night bee of Queensland…?!!
As you know, most of Australia’s ~2000 native bee species are soil nesting bees. In addition to providing patches of appropriate bare soil (among lawns, garden beds, or in mounds), we can add other components to increase the appeal to female bees looking for nest sites. Adding large stones or pieces of concrete that provide sheltered overhangs can increase the likelihood of bees starting nests. In the photo below, an old grave in a cemetery provides a sheltered overhang and you can see the soil below is riddled with insect burrows, including those of bees. Some bee species also favour nesting in soil among small pebbles, so providing little collections of them on patches of appropriate soil may be of benefit too.
We had a massive day at the Logan Eco Action Festival on the last Sunday of May, speaking to hundereds of native bee-interested people! Our live stingless bee hives with observation panels were a hit as always, and so were our new pollination info-graphics by Loy. Thanks to eveyone who came by and had a chat. We enjoyed hearing all your bee stories. Thanks to Bec Condon and everyone at Logan City Council for having us! See you next time.
Asian honeybees (Apis cerana - pictured below) are now pretty easy to see around Cairns, QLD, and recently I saw them daily as I’ve walked around Cairns city. A. cerana was accidentally introduced to Cairns in 2007, and despite a short-lived government funded eradication program that ended in early 2011, they have managed to do pretty well. Unfortunately that means Australia has them now for good...! Another invasive species to put pressure on Australian ecosystems and biodiversity (through things like competition with native species for floral resources and nest sites). Honeybee keepers in Australia are also concerned about the potential for a resident population of A. cerana to make honeybee pest and disease transmission more complicated to detect and manage. A few months ago, another incursion of A. cerana occurred, in Townsville, where authorities found a single colony on a ship in port. The colony was destroyed, along with the Varroa mites it was found to be harbouring. Varroa mites will not affect any of our native bee species, only introduced Apis mellifera and Apis cerana (it coexists with A. cerana, but kills or weakens A. mellifera colonies).
Contrary to popular belief, pollination by Honeybees does not result in one third of the food we eat…!!! It’s probably much closer to one sixth or one ninth… Yes, about one third of the food we eat is the result of BIOTIC pollination (as opposed to wind pollination in cereal crops), but honeybees (Apis mellifera - pictured below) are just a part of the pollinator mix. Many of the other 20,000+ bee species on the planet also perform crop pollination, as do other insects such as flies and wasps. While determining precise, generalisable percentages is very difficult, we know from research in the UK that of the crops requiring biotic pollination (in the UK, in 2007), honeybees likely perform only a third of the overall pollination (so, are just responsible for a third, of a third, of the food produced in the UK in 2007!). The majority of biotic pollination in this instance was likely the result of non-honeybee native bees, and other native insects. We also know that globally, yields of a wide range of important crops increase significantly when visited by wild, non-honeybee pollinators, and often wild pollinators are more effective crop pollinators than honeybees. So, honeybees are indeed important to our global food production (even one ninth is very significant for a single bee species!), but other non-honeybee wild pollinators likely collectively contribute more, and as such must be given the recognition and protection they deserve.
Bee or Fly? The picture below is of a Hoverfly. People often misidentify Hoverflies as Australian native bees, particularly the darker coloured species. Other than the shape of the head, an easy feature to tell a fly from a bee is wing number. Bees have four wings, while flies only have two (a single pair). Hoverflies (also called Flower Flies) are collectively the second most important group of pollinators on the planet, after bees! As well as the Hoverflies, there are many other fly families with species that are pollinators.
Boy teddy bear bees doing what boy teddy bear bees do. At night, males of Amegilla (Asaropoda) bombiformis roost on lower twigs or stems of shrubs, clinging on with their mandibles. Sometimes five or more can be seen attached in a snug row. Males of many solitary bee species snuggle up and roost in groups like this at night. Teddy bear bees are close relatives of blue banded bees. The males of both species roost in the same way, and the females of both have similar soil nests. Also like blue banded bees, teddy bear bees are common garden visitors, and are also 'buzz pollinators'.
A female native Blue Banded Bee, Amegilla (Zonamegilla) cingulata (pictured). Yesterday I visited a friend who lives in a mud brick house and has about 50 of these bees nesting in one of her walls. They are a solitary bee species, the females of which nest individually (although often near each other, in aggregations). A single female excavates a burrow in the ground (or a mud brick, or the side of a dry riverbank or gully), where she lays just five or so eggs (in individually partitioned cells). She forages on lots of flowers, makes small parcels of pollen and nectar to provision each of her eggs, and then seals up the nest. Having done what female solitary bees do, she then usually dies. Over time, the eggs develop into larva, and then pupa. Finally, fully developed bees emerge from the nest, and go forth and repeat the process (males just live lives of mating, eating, and hanging out at night in posses, on the undersides of shrubs). These bees are 'buzz pollinators', and are great pollinators of tomatoes
These are a collection of posts that have appeared on the Bee Aware Brisbane Facebook page over the last couple of years.