It's not news that bees are in trouble. And not just honeybees. Declines in native populations of wild bees have been noted as well. This could present a serious problem for the many agricultural crops we depend on for food. But some recent research suggest that the loss of biodiversity of bee species, separate from the actual number of individual bees, may have far-reaching implications for ecosystems as a whole.
In an experiment carried out in Colorado and described in the New York Times, researchers studied 20 plots of meadowland of approximately 500 square feet each. Individual insects of the most populous species of bumblebee were caught in nets and removed from the test plots, and the plots were patrolled to see that this species remained excluded. According to their mathematical models, the researchers expected that the other species of bumblebees present would fill the gap and pollinate the flowers that the removed bee species had previously visited. The flowers, larkspur specifically in the study, wouldn't ″notice″ any difference.
But things turned out differently than expected. With the most populous species removed, the other species of bees took advantage of the lack of competition and broadened the range of flowers they visited. Whereas before, certain species of bees concentrated on certain species of flower, the bees now visited many different kinds of flowers. This reduced the likelihood that on each flower visit a bee would be carrying the pollen of that same kind of flower so that pollination could occur. Because of this change in bee behavior, the larkspur plants in the test plots ended up producing about 30 percent less seed than in control plots, a significant impact from an ecological perspective and a reminder of the interconnectedness of the natural world.
To read more about this study, go to NY Times Science.