Friday, June 21, 2013

Native Bees, Honey Bees and Natural Areas

Spring beauty bee © Beatriz Moisset

It is common practice for nature centers to have a beehive. Often, a glass wall allows observation of the colony's busy life, seldom failing to catch the eye of visitors. This serves an educational purpose by providing a great opportunity for a behind-the-scenes peek at the private lives of honey bees. Thus, visitors learn about these useful insects and their role as crop pollinators.

Honey bee © Beatriz Moisset
Sometimes I wonder if we are delivering the right message. The purpose of nature centers is to protect natural wildlife and to promote conservation of natural resources. This is clearly stated in many of their mission statements. Honey bees and chickens are domestic animals. They are both important to agriculture. However, we don't keep chickens at the bird feeders to teach about birds. Do we need honey bees to teach about insects?

Nowadays, agriculture relies heavily on honey bees; however, we must bear in mind that honey bees were introduced to this continent by Europeans a few hundred years ago. Until then, all pollination was accomplished by native pollinators, more than 4,000 species of bees and many other insects, such as flies, moths, wasps and even beetles, as well as some birds and bats.

Jack-in-the-pulpit © Beatriz Moisset
Fungus gnats © Beatriz Moisset

Native plants didn't need honey bees then, and they don't need them now. A few examples should suffice. In early spring a number of delicate little flowers carpet the forest floor. They are in a rush to take advantage of the sunlight during the absence of foliage and don’t last long. Thus, they are called "spring ephemerals." None of them is visited by honey bees. In fact, many resort to highly specialized pollinators which have been around for as long as the plants themselves. Skunk cabbage and Jack-in-the-pulpit are pollinated by flies. Spring beauties and trout lilies are visited by an assortment of bees and bumble bees; but get help, in particular, from their own specialized pollinators, the so called spring beauty bee and the trout lily bee respectively.

Azalea bee © Beatriz Moisset
Shortly after, when azaleas bloom another set of specialists comes into service, the buzz pollinators. These are experts at shaking the pollen out of the flower stamens. One of these experts is the azalea Andrena bee. Its name needs no explanation.

So, what are honey bees doing in the meantime? They devote their time to the nectar and pollen of willows and maples. Thus, honey bees make use of these trees, but the trees themselves benefit from an abundance of native pollinators and don't need the extra help. Honey bees also gather pollen from hazelnuts. This is good for the bees but doesn't help the trees in the slightest because they are wind-pollinated.

Magnolia and mordellid beetles © Beatriz Moisset
Honey bees don't pollinate azaleas or rhododendrons. They also ignore dogwoods. As for magnolias and their close relatives, tulip trees, these plants are primarily pollinated by beetles and flies, all of them native. Honey bees are more inclined to visit generalist flowers, the ones receptive to a wide range of pollinators. Therefore, native pollinators are all that the flowers need.

Another problem with honey bees in natural areas is that they may contribute to the spread of non-native plants by pollinating them preferentially. They also may compete with native pollinators for floral resources.
Tricolored bumble bee © Beatriz Moisset
In summary, native plants and native pollinators are members of a complex community. They have adapted to each other and work well together. Honey bees, while important to agriculture, are not needed in natural areas. The only justification for keeping beehives at nature centers is to use them as a gate to the understanding and familiarization with insects and their usefulness. If the visitor leaves the nature center as ignorant of native pollinators as he was when he came in, then the center has failed to deliver the most valuable message of the bees.

It is imperative that naturalists and educators at nature centers with beehives devote time to informing the public about native pollinators and their significance to native plants. Posters with this information would also be helpful.
Augochlora pura © Beatriz Moisset

Tom Bain presents some good suggestions in his blog "GeoEcology. Earth and life through time..."

 "There is an essential piece missing from the typical presentation about pollination in many nature centers, that is the discussion of native pollinators and their essential continuing role in native and not so native ecosystems. Each presentation about honey bees should be accompanied by a hands-on activity to plant native plants that are partners to native pollinators, or the construction of simple solitary bee houses from dry bamboo canes or wood blocks. We would make progress if our children earned great take-home's like solitary bee bundles in place of coloring-in honey bee illustrations; and, planting native seeds to grow purple coneflower or other natives in place of marigolds, etc. A little effort and a subtle change in emphasis would shift attention to native pollinators."

© Beatriz Moisset. 2013

Sunday, June 16, 2013

One Bite out of Three and Wildlife

So, we all agree that we owe one third of our food to pollinators. Now let us stop thinking about us; instead let us devote a few minutes to our companions on planet Earth. Does wildlife need pollinators as much as we do? It seems that nobody has looked at this matter systematically, thus, it is not an easy question to answer. Yet, we can try.

I will try to look at the diets of some feathered and furred creatures, mammals and birds and ignore for now the scaly or slimy sorts, amphibians, fish and reptiles. I will merely list the foods that need the services of pollinators, rather than attempting to estimate percentages for lack of information in the matter. What we are trying to see is whether wildlife requires the services of pollinators. Also, I will not bore you with long lists of animals and their diets, simply limit myself to some better known examples.

Birds that come to our backyard feeders are easy to observe. They show a preference for sunflower, thistle and peanuts. Summer and winter, many birds depend on berries, from blueberries to raspberries to crabapples to holly. Of course, not all their food is insect pollinated like the ones mentioned above. Many birds feed on insects and or grass seed. You can learn more about the role of pollinators on the diets of some of the most beloved songbirds such as wood thrushes and blue birds at the North American Pollinator Protection Campaign fact sheet.

Another common wildlife of our forests and backyards is the squirrel. The eating habits of squirrels are similar to ours as a look at the way they dig through our leftovers proves. When there is no human garbage around, they go through a variety of berries, seeds and tender leaves. It would be safe to conclude that they are as indebted to pollinators as we are. The same could be said of raccoons.

One animal that symbolizes wildlife more than most is the bear. Let as take a quick look at what a bear eats through the year. When it comes out of hibernation, there isn't much plant life around, except for skunk cabbage, and skunk cabbage becomes its breakfast, lunch and dinner with some Jack-in-the-pulpit as a side dish. A bear must have a strong stomach because these plants have tiny salt crystals that would make most other animals, including us, very, very sick. I mentioned in previous posts that skunk cabbage and Jack-in-the-pulpit are both pollinated by small flies, which are the only pollinators flying around so early in the season.

Other foods become available later on. A bear will add some vegetables to a wide range of other things. When fall comes and berries ripen, it is the time to eat berries. In areas where blueberries are abundant, a bear is likely to spend long hours in blueberry fields, gorging itself. Do I need to repeat that most berries are pollinated by insects?

The many herbivores, deer, bison, skunk, rabbit, may eat mostly wind-pollinated grasses; but they also need other nutrients that can only be obtained from flowering plants, from clovers to asters.

Finally, if you are wondering, even meat-eaters benefit from pollinators, since much of their food, the herbivores, feed thanks to them.

Now, we have further reasons to be grateful to pollinators. It isn't just us, humans, who are in their debt, but practically all other animals of our fields and forests.

List of Articles 

© Beatriz Moisset. 2013

Friday, June 7, 2013

A Sea of Blue Flowers

Field of Camas on a private property in Oregon. © Beatriz Moisset
When Lewis and Clark parted in their expedition across the continent in 1804, many wonders awaited them. When crossing the Mississippi they left behind many familiar things and faced others totally unknown to European settlers.

Blooming flowers in June. © Beatriz Moisset
A marvelous, astonishing sight west of the Rocky Mountains was a valley that looked like a blue sea with gentle waves rippling across it. A dense carpet of blue flowers stretched for miles deceiving the eye to the point of looking like a vast lake.

The flowers, unknown to them, were the camas lilies (Camassia quamash) of the west. They look like small lilies, although they are more closely related to the agave than to other lilies. Their nutritious bulbs provided an important food to the local peoples. Despite the laborious preparation to eliminate toxic components the Nez Perce and other tribes resorted to this food through the winter pounding it into flour and baking it into bread-like cakes. Lewis and Clark were happy to supplement their dwindling supplies by purchasing camas lilies cakes from the Nez Perce.

Nature Conservancy Camassia Natural Area. © Beatriz Moisset
Most of the land of the camas lilies has been taken for cultivation of crops. We can only imagine the full glory of the blooming fields of two centuries ago when looking at the scattered small plots which represent their last remnants.

One of the familiar things the expedition members left behind was the honey bee or domesticated bee. There were no domestic bees west of the Mississippi in those days, only native ones. It would take another fifty years for some enterprising folks to carry beehives from the eastern United States to California. Only one hive survived the ordeal of such a trip. Many years passed before honey bees became established and significant beekeeping operations got underway.

Native bumble bee pollinating a camas. © Beatriz Moisset
 Camas lilies were not deprived of pollinators. They had no need for honey bees; abundant insects made their living from gathering their pollen and nectar. When the new crops and agricultural methods including monocultures took over much of the land, the honey bee became the workhorse of crop pollination.

Nature Conservancy Camassia Natural Area. © Beatriz Moisset
Where did the native pollinators go after the numbers of camas lilies shrank to insignificance? Probably we'll never know. We can guess that some found pollen and nectar elsewhere and survived, although their numbers, too, must have been reduced. We acknowledge the disappearance of a way of life and of the seas of blue flowers. The pollinators of centuries ago went about their job silently and unnoticed. Thus, we cannot appreciate their absence.

One Bite out of Three

© Beatriz Moisset. 2013