NATIVE BEES: WHO ARE THEY, WHAT THEY DO, AND HOW TO KEEP ‘EM HAPPY

Presented by Anthony Melathopoulos (Dalhousie University)

There is much more to those little buzzing creatures than meets the eye and more of them than many might realize.  I’m referring to native bees; there are hundreds of species in Nova Scotia ranging from very small to surprisingly large! Honeybees, one of the most common bee species that may come to mind, are however a domesticated species.

Unfortunately all native bee species around the globe are in decline largely due to anthropogenic causes:  habitat fragmentation and pollution.  Anthony Melathopoulos hosted the Native Plant talk on March 15, and discussed how to recognize native species of bees, their role in the environment, and how to house them and keep them content in your own gardens.

First, a bit of history:

One hundred and fifty million years ago native bees separated off from wasps on the evolutionary path. They co-evolved with many of the angiosperms (flowering plants) they are commonly associated with.  They are dependent on plants for their entire livelihood.

Who Are They?

As there are over a hundred different species in Nova Scotia, many bees do not look like the typical black and yellow striped critters that come to mind and some creatures, such as yellow jackets, that have this colour pattern are in fact wasps, not bees.

To distinguish bees from others it is important to note that they are hairy, have two pairs of wings, and sturdy antennae. Compared to flies they have a longer abdomen, larger eyes on the side if their head, and can fold their wings behind their back when they are resting.

Bee colonize consist of a queen, workers, and drones. The queens are about the same size as the workers just with a larger abdomen and they do all the reproducing.

There are around 400 species of bees in Canada with a wide range of appearances. The main species discussed were: leafcutter bees, wild bumblebees, digger bees, mason bees, and sweat bees.

Leafcutter bees are not social bees. They are quite small; fly size or smaller.  They are black to bluish in colour, carry pollen on their abdomen, and nest in holes made by beetles in wood.

Bumblebees are a medium to large size bee. They are a social species and often occupy abandon rodent dens. They carry pollen on their legs, and their colouring is species specific.

Digger bees are a solitary, small species that reside in the soil. They are rather specific when choosing plants and can be identified by their unique velvety area between their eyes.

Sweat bees are a small bee with a metallic/ iridescent gold or green colouring. This species is both social and solitary and lives in the soil or soft wood.

What Do They Do?

Bees make honey yes, but they also pollinate flowers, an essential duty for maintaining life on Earth. The processes involved, their routines, and life cycles are quite interesting.

Most bees are not picky when choosing which flowers they visit and move from bloom to bloom as the season goes in. Some bees however, are specialists. For example some live exclusively off willows.

With the pollen the bees collect they pack it into honey combs and use it to feed their young.  (It is interesting to note that honey from different flowers is different colour and even tastes different!)

Reproduction habits vary among species. Three species’ habits that were highlighted are: bumblebees, leafcutter bees, and mason bees.

Bumblebees are seasonal and live underground over winter. When it is warm enough they emerge from their den and begin to gather pollen to make wax and honey. They only have about four babies which are very small at birth. They grow throughout the season and are the largest in the fall when they mate and the cycle continues again.

Leafcutters lay multiple eggs inside a tube such as a twig and the babies chew their way out.

Mason bees make a cocoon in preparation for the winter.

Different species emerge from their dens at different times in the season. In April the mason bees and digger bees come out, followed by the leaf cutters and bumbles in mid-season, and finally the sweat bees near the end of the summer.  Because of this alternating pattern, in order to support bees in your garden through the season, you need to ensure there are successful blooms to accompany them.
This leads us to:

 How to Keep Them Happy

An important factor is there needs to be enough plants and a diversity of flowers within the garden as not all bees can use the same flowers.

Providing nesting sites and water can ensure happy bees!
Many bees nest in holes and making homes for them can be simple:

– take a block of wood and drill holes all the way through the block
– if the block is in two pieces you can break it open and get the cocoons to keep them safe

-plexiglass used as a cover allows for observation of them in their holes
– securing a bunch of straws together will attract bees that use tubes for nests such as the  leafcutters.

These are just some basic ideas. Visit the how to build nesting boxes blog for more ideas and insights on how to share your summer season with bees!

 

Written by Kaitie Porter

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3 thoughts on “NATIVE BEES: WHO ARE THEY, WHAT THEY DO, AND HOW TO KEEP ‘EM HAPPY

  1. Pingback: Lizzy Hill » Blog Archive » Halifax gardeners pressure nurseries to sell more native plants

  2. I have noticed some interesting patterns in the bees in my garden in Halifax. Earlier in the summer, I had a lot of bumble bees (as well as many other bees). Then there was a period in late July, when there were no medium to large size bees of any sort. Now I have a lot of medium sized bees. There have been bee friendly flowers the whole time, and I never use any pesticides beyond an occassional Bt on my kale (which shouldn’t affect bees)
    Do bees have seasons? Do bumble bees normally disappear later in the summer?
    I have a serious infestation of european fire ants, which have nests throughout my property and are very aggressive. So i wonder if they could be affecting my bee populations, particularly those which may be nesting underground.

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