Backyard Biology

Nature stories from my backyard and beyond

Nature Stories

Our Native Daughters

Tuesday, June 8, 2014

Imagine a world without honeybees. It’s not hard to imagine. All one has to do is a search on the internet for life without honeybees. My search showed 1,310,000 hits. Many of them claim that 1/3rd of the food we eat will no longer be available to us since they are pollinated by bees - mostly honeybees. Some even put a number to the amount of years we can survive before starvation dooms the entire human race. Regardless of the claims, honeybees do pollinate many of the foods we have come to rely on. One article*, a wikipedia article of a list of crops pollinated by bees, lists well over 100 plants that depend on them for pollination. Among the crops pollinated by honeybees are onions, cashews, celery, broccoli, cauliflower, cabbage, peppers, watermelons, coffee, cucumbers, squash, strawberries, cotton, apples, alfalfa - well, you get the idea. With all of the talk of the disappearance of honeybee colonies, one can only imagine a pretty bleak world.

Now imagine a world before honeybees. That is not very hard to imagine either. That world was North American before 1622, the earliest record of honeybees being imported to the Americas. That’s right. Before 1622, there were no honeybees in North America. They are not a native bee. One might even consider them an invasive species!

There are some 4,000 bees that are native to North America. They, along with the wasps, flies, butterflies, moths, birds and others were responsible for plant pollination before the arrival of the honeybee. These native bees come in a wide variety of sizes, colors and lifestyles.

The largest and best-known of our native bees is the bumblebee. Like the honeybee, thebumblebee bumblebee is a social bee - living in large colonies with a queen and many workers. The bumblebee nests underground, usually in an abandoned mouse nest. Unlike the honeybee however, the hive lasts only one year, with only the queen surviving the winter.

Similar in looks to the bumblebee, but quite different in lifestyle is the carpenter bee. Like most of our native bees, the carpenter bee is a solitary bee. There is no hive, per se. In the solitary bees, the queen prepares a nest, lays an egg and provisions it with food - a mixture of pollen, nectar and saliva. This chamber of egg and food is sealed up and another is created. Once the queen has created and provisioned a number of chambers, she closes up the nest and leaves to start another nest. There are no worker bees to watch over the eggs and feed the young. In fact, there are no worker bees at all, only male drones and queenns.

In the case of the carpenter bee, the queen drills a perfectly round hole in a piece of soft wood or pithy plant stem. The tunnel quickly makes a right-hand turn and in this tunnel she lays her eggs - one egg plus food per chamber.

Two other bees that use wood cavities for nest sites are the mason bees and the leaf-cutter bees. Generally, these bees do not excavate their own holes, but will utilize existing holes made by beetles or other insects. Their names suggest the materials they use to divide their nest into chambers - the mason bees using mud and the leaf-cutter bees using leaves.

Then there are the ground-dwelling bees. Among these are the sweat bees, polyester bees, squash bees, digger bees and mining bees. sweaat beeSweat bees, small dark iridescent bees, are named for their habit of licking the sweat off a person for the salt. Polyester bees are so named for their creation of a plastic-like substance that they use to surround the egg chamber. Squash bees, as the name suggests, are pollinators of plants in the squash family. Like the others in this group, digger and mining bees construct their nests in a hole in the ground.
Some of these bees will gather in large numbers in an open patch of dirt in one’s back yard. The dirt patch may be filled with nest holes and dozens of bees can be seen flying back and forth over this patch. What may look like one large nest of bees, however, is actually many solitary nests. In a matter of a day or two, the holes will be plugged up, the bees gone for the year and no trace of the nests that lie just below the surface.

Being native to North America, these bees have evolved with the native plants. Therefore they are in tune with the needs of the plants as pollinators, and well adapted to the climate conditions they encounter. Many of them fly earlier in the spring and later in the fall than the honeybee. They are much more likely to be active in inclement weather. And some of them have developed techniques to get at the pollen of plants that honeybees are not able to access. Ounce for ounce, they are much more efficient pollinators than honeybees.

So, imagine a world without honeybees. It is not hard to imagine. All I have to do is look around my back yard. I have spent the last few weeks searching for bees. I have seen sweat bees, carpenter bees, bumblebees, mason bees, digger bees - but no honeybees. Despite this lack of honeybees, I am still expecting a good crop of my garden fruits and vegetables, all thanks to the pollination done by the native bees.

However, lest we get too complacent that we can always rely on our native bees should the honeybee disappear, keep this in mind. Recent evidence suggests that our native bees, like the honeybees are also disappearing. Much of this is due to habitat loss. Since many of our native bees are flower specialists, pollinating only a few types of flowers, we need all of our native bees. However, with many farms producing only one or a few types of crops and many of our large lawns producing no flowers to speak of, our native bees are suffering.

Imagine a world without honeybees and without native bees. Not a pleasant world at all.

*http://en.wikipedia.org/wiki/List_of_crop_plants_pollinated_by_bees