Bees: The World’s Star Pollinators

A World Without Chocolate? Try to imagine our modern world without apples, pears, citrus fruits, carrots, grapes, olives, tomatoes, and almonds. Then try to imagine our California wildlands devoid of beautiful spring wild flowers. We know you can’t imagine the world without chocolate so we won’t ask. About 1/3 of our vegetable, fruit, and nut crops (including cocoa beans), along with many of our wildland flowers, depend on the pollinating services of bees. If we extend our thinking to the tropics, virtually all flowering plants depend on animals for their pollination, and the majority in the New World and Old World tropics are bees. The world’s star pollinators, bees, play an important, but sometimes invisible role in our everyday lives. And, their services in wildlands are free.

Pollinator Stars: Bees depend on pollen and nectar for their reproduction and survival. They are specially equipped to collect these resources. As they buzz from one flower to another, pollen gets caught in specialized hairs and other special pollen-collecting body structures. Some of this pollen makes it back to the nest to feed bee babies (larvae) but some of it accidentally rubs off onto the reproductive parts of other flowers. If the flowers are of the same species, cross-pollination will likely occur. Nectar (or sugar water) fuels their foraging flight and also is added to nest cells to feed baby bees.

Celebrate Diversity: Bees are very diverse in species and in habits, which makes them especially efficient at pollinating diverse flower species such as ours in California. There are about 1,500 different bee species in California, ranging from the giant black Xylocopa, or carpenter bees, to the tiny Andrena, which look more like winged ants than bees, to the gorgeous metallic green “flying jewels” known as Osmia. Only the common European honey bee (Apis mellifera), the Alfalfa Leaf-Cutter bee (Megachile rotundata) and a close relative, Megachile apicalis, are exotic to northern California.

Each of these bee species is specially equipped for the flowers with which they come into contact. Their body structures and even their sense of timing have evolved to form complex seasonal and spatial relationships with diverse plant species. In other words, certain flowers bloom and certain bee species emerge from their nests according to a tight schedule so that the right bees have access to the right plants during specific times of year.

Native Californians: We don’t often notice native bees (non-honeybee species) unless we are looking for them. In contrast to the social honey bees, which make hives and live in colonies, more than 95% of our native bees are solitary in life style. That is, a single female bee mates with a male, and then goes about foraging and constructing a nest by herself to raise another generation of bees. There are no social structures or colonies associated with the solitary bees.

Declining Populations: Recent surveys (conducted in the early to mid 1990s) indicate that pollinators world-wide are declining. The cause for decline is habitat destruction brought about by human development. This was the subject of a recent book, “Forgotten Pollinators,” and has been a focal area for much new research aimed at how to conserve and protect existing pollinators, - especially bees. One of the outcomes of the downward trend of pollinators has been to awaken the scientific community to the need for extending information to the public and increasing general awareness of bees and other flower visitors to protect this valuable natural resource for the future.