丁香园AV

The Pollination Ecology Lab at 丁香园AV

Pollinators of Southern British Columbia

Female bees are the most important pollinators in our region, because they collect pollen and nectar to feed their offspring.  This means they visit more flowers per unit time and are more likely to contact and move pollen than other flower visitors like flies, wasps, butterflies, and birds.  But of course, any animal that visits a flower has the potential to be a pollinator!  

Almost 90% of flowering plants need pollinators to reproduce, so bees are important for ecosystem stability.  Like all animals, pollinators need two basic things:  food and a place to nest. I've created this page with information about food and nest requirements because I get asked for information on pollinators of BC so often!  I am most frequently asked questions about honey bees, which are not native to BC and are best considered an agricultural animal.  Next frequent are questions about the identity of particular pollinators, or how homeowners can help with bee conservation.  The first thing you need to know is that there are more than 450 species of bee in BC (and counting!).  That is more than the number of birds in all of Canada!  So identification to species can be challenging and often isn't possible from a photograph.  Regarding conservation, the number one threat to pollinators (like all plants and animals at risk of extinction) is habitat loss.  So, considering how you can create habitat in your backyard or on your balcony is a great place to start.

Keep scrolling down for information on how to recognize some of the more common bee families in BC, as well as suggestions for garden plants that are highly attractive to bees.   A version of this page is available as a 2-page pdf:  Bees and Gardens.   Also available (bottom of the page) is info on the most pollinator-attractive wild plants from habitat restoration projects in Metro Vancouver.

For information about the status of pollinators in southern BC, you might be interested in a report former student Julie Wray and I wrote for Metro Vancouver.  The Report includes some information about wild plants to consider.  

Also check out my "Plea for the Bees Needs" presentation on the "Videos" tab, and here are two excellent resources:

for Invertebrate Conservation (tons of info, including planting guides and plans for making bee nests)
an initiative of Earthwise Society, with great info on plants for our region

Pollinator Groups

Bumble Bees

• Social:  have a queen and workers
• Most in our region are ground-nesters, using existing holes (like mouse holes, or air spaces in compost!).  A few nest above ground, and sometimes will occupy chickadee nest boxes.
  
• Active in Spring, Summer, and early Fall. 
  

Bumble Bees of the South Coast of BC

Clockwise from upper left: 

• Bombus melanopygus has an obvious red end to the abdomen; 
• B. bifarius also has red on the abdomen but the tip is yellow, and there are two white spots on the back of the thorax;
• B. mixtus is a 'boring' looking bee, with a rusty end to the abdomen but not as clearly red as others, and the bee tends to have longer hair giving it a fuzzier appearance;
• B. occidentalis is being considered for listing under Canada's Species at Risk Act, and is very uncommon.  The abdomen tip is white.  Please let us know (with photographic proof!) if you see this bee in the Lower Mainland!!
• B. vosenesenskii has a yellow face and a yellow stripe on the abdomen tip;
• B. flavifrons comes in two colour forms, an orange abdomen tip or a black one (inset).  
  
  

Sweat Bees

• Solitary or semi-social bees;  each female starts a nest in many cases, but there are exceptions.
• Nest in the ground.  Holes are often excavated in compacted soil with little plant cover, sometimes in banks.
• Range greatly in size;  common species include some that are just a few millimeters in length, other common species are around 1.5 centimeters.  Include some metallic bees.  Body type is long and thin.
• Active in Spring and Summer.

The photo at the upper left shows a nest aggregation (individual nest at upper right);  scale is about a meter across.  Most bees in the photos are about 1-1.5 cm in length  except the two photos at lower left, where bees are less than 0.5 cm. 

Mining Bees

• Solitary bees;  each female starts a nest.
• Nest in the ground.  Holes are excavated by the female, just like sweat bees.
• Range greatly in size but most are about 1-1.5 centimeters in length.  Body type long and thin.
• Active mostly in Spring in our region.

Examples of mining bees in our region.  Note the hairy eyebrows on the bee in the lower right--diagnostic for this group.

Hairy-Belly Bees

• Solitary bees;  each female starts a nest.
• Most nest in existing holes in wood (some nest in ground).  Many will use 'bee condos', or will nest in fence posts or wood siding.
  
• Most species around a centimeter in length or so;  body type is more squat and rounded.  They are called "hairy-belly bees" because they carry their pollen under their abdomen (notice the picture lower left).
• Mason bees use mud in nest construction and are active mostly in Spring.  Leafcutter bees use leaves to line nests and are active in Summer.  A few species in this diverse group are managed for crop pollination

Upper left shows a blue orchard bee (a "BOB") on a "bee condo".  Lower right shows typical holes in leaves made by leafcutter bees. Note the pollen carried on the 'hairy belly'.

Honey Bees

• Highly social, a single queen in a nest with thousands of offspring workers.
• Nest in cavities in nature.  Introduced worldwide for use in pollination of agriculturally important crops.
  
• When managed, nest in pretty white boxes!
  
• Can be active year round if weather is satisfactory.

Other Pollinators

Include hummingbirds, butterflies, flower flies, other flies, beetles, wasps....anything that visits a flower!  These groups visit flowers to feed themselves (sometimes as part of a variable diet) and their offspring are often fed other things. Nests are quite variable.

What to Plant in Your Garden or Habitat Restoration

To make any area a refuge for pollinators, you should aim for the following:

• Long bloom times (early spring is especially important!)
• Lots of variation in shape, size, and colour--this attracts lots of variation in pollinators.
• In general, "easy access" flowers where the pollen is visible will be attractive to more pollinators.
• Large patches of each kind of flowering plant--about a square meter of each, if you have space.
• No pesticides, of course!  And we encourage you to be forgiving of some 'weeds' like clover and dandelions.
• Consider nest sites:  bee condos, places ground nesters can use, and plants with hollow stems.

Below are some of our data from research projects in different areas of southern BC, as well as in gardens near Victoria! 

The colours indicate pollinator type, and each bar is for a different plant.  These "top-25" lists show which plants had really high visit rates by pollinators, and also useful is that bars with lots of different colours attract many different pollinator types.

In all cases the names of my amazing students who collected the data as part of their theses is indicated.  Please be sure to leave these attributions on the graphs if you wind up using them!