Bombus ternarius, Tricolored bumble bee on mountain mint |
Recently I discussed
the idea of allowing dandelions on the lawn to benefit pollinators. I
pointed out that such practice only benefits a handful of generalist
pollinators, but not the specialists. The latter can be more numerous
than the former when they are all counted. They also account for the
wide diversity of nature.
Bombus impatiens, Common Eastern Bumble Bee on blanket flower |
Andrena cornelli, Azalea andrena on azalea |
Let me expand on the
concept of biological diversity or, as it is often called by
ecologists, biodiversity. There are 4,000 species of bees in North
America, from the familiar, big and plump bumble bees to tiny bee
species that remain unnoticed to all except to those who study bees.
Bear in mind that even bumble bees aren't just one single species but
about 46 in North America.
Augochlora pura on thistle |
Nomada, cuckoo bee on spring beauty |
Bee species vary not
only in size but in many other ways. Some are active from early
spring to the end of fall. Others complete their whole cycle in just
a few weeks and remain dormant the rest of the year. Some are adapted
to different climates and cover a large area, others are more limited in their geographic distribution.
There are even some species, called cuckoo bees, that don't bother raising a family. Instead, just as cuckoo birds, lay their eggs in the nests of other bees.
Some bees have a long tongue that enables them to reach into fairly deep throated flowers. Others can only visit flowers that are relatively flat and open. Finally, some are very particular about the flowers they visit.They collect pollen from only one species of plants (monolectic) or a few related species (oligolectic). They may visit a wider range of flowers for nectar, but only their choice plants will satisfy their pollen needs.
There are even some species, called cuckoo bees, that don't bother raising a family. Instead, just as cuckoo birds, lay their eggs in the nests of other bees.
Some bees have a long tongue that enables them to reach into fairly deep throated flowers. Others can only visit flowers that are relatively flat and open. Finally, some are very particular about the flowers they visit.They collect pollen from only one species of plants (monolectic) or a few related species (oligolectic). They may visit a wider range of flowers for nectar, but only their choice plants will satisfy their pollen needs.
Agapostemon splendens on seaside goldenrod |
Lasioglossum pilosum on coneflower |
Losing a few of
these specialists may not be catastrophic, but it is preferable to
preserve as many of them as possible. A rich variety of species
confers resilience to an ecosystem. This is why it is important to
have a wide range of specialists along with the handful of
generalists. One way to help the specialists is to plant a variety of native plants to ensure that some of them satisfy their needs.
Colletes on Cerceris canadensis |
Bombus perplexus, confusing bumble bee on common milkweed
|
All images ©
Beatriz Moisset
List of articles
Beginners Guide to Pollinators and Other Flower Visitors
© Beatriz Moisset. 2016
List of articles
Beginners Guide to Pollinators and Other Flower Visitors
© Beatriz Moisset. 2016
Fabulous photos and a very interesting article.
ReplyDeleteI believe your photo of Augochloropsis metallica is actually Agapostemon
ReplyDeletehttp://bugguide.net/node/view/1021174/bgimage
Indeed! Thanks for catching that. I substituted one image for another and forgot to change the caption. Now it is fixed.
Delete