The Amateur Anthecologist: Floral Visitors

Bombus sp. on Echinacea purpurea

The following series of photos (twentieth post in the Floral Visitors series) will be short on commentary. This is a mixture of native pollinators (and honeybees which are nonnative) on both native and nonnative (garden) plants. The title, Floral Visitors, is descriptive of the fact that pollinators may visit a flower without necessarily contributing to pollination, thus they are merely floral visitors gaining sustenance from the floral rewards (nectar and/or pollen) while the plant gets nothing. This is a concept of anthecology (literally translating to flower ecology) in which plants support pollinators which may be important for the reproduction of other plant species. With enough biodiversity, the hope is that things balance out and everything gets what it needs. When diversity decreases or foreign species are introduced (introduction of nonnatives, benign or noxious) the system is thrown out of balance. I may sound hypocritical when saying this since I plant a lot of nonnative flowers in my garden, but my mere presence is disrupting the natural balance by taking up space (houses, roads, etc.) as well as byproducts of my presence (pollution from light, etc.). Perhaps I'm just being cynical, but when I started seeing life on the scale of my photography I started thinking about life in a new light, and that we ourselves are an invasive species.

My hope is that be illuminating the subject, and not only focusing on honeybees (no doubt paramount to our proliferation as a species), others may see the small life that I see which is more complex than we can know at our current level of awareness. Many of the smaller species of bees do not travel long distances, some no greater than 200ft, and so require food sources within that small span of their nest, or vice versa. Predatory and parasitic wasps, the vast majority are of little to no threat to people, require specific hosts of prey to survive. Either by pollination or by pest reduction, these small creatures are doing us a great service where they are prevalent, but the use of pesticides and the lack of nutrition (flowers) degrade their numbers thus requiring the use of honeybees, which is expensive.

A study by the Xerxes Society (Losey et al. 2006) reported an estimated $57 billion in ecological services provided by insects in the United States. Why would we not want to take advantage of these free services, use less pesticide, and take some of the pressure off of honeybees? The manufacturers of pesticides would not like to see this happen, and so the stereotype of insects being malicious and evil, the fear of these very small creatures, is propagated and shoved down our throats. Surely the number of benign, even beneficial arthropods far outweighs the ones harmful to us and our things, so long as a balance is maintained. What can you do? Plant flowers (preferably native to your region), and use less pesticide.

Apis mellifera on Navarretia squarrosa, an Oregon native.

Apis mellifera on Holodiscus discolor (oceanspray). Though the flowers of this native shrub were visited by a variety of small native bees and bumblebees, the honeybees practiced the peculiar behavior of "swimming" through the inflorescences.

Apis mellifera on Holodiscus discolor

Calliopsis sp. on Horkelia daucifolia

Plantago lanceolata with a honeybee, making it rain pollen.

Apis mellifera on Allium cepa, aka common onion.

Lucilia sericata on Allium cepa

Gasteruption sp. on Allium cepa. Wasps in this family feed on flowers as adults, but the larvae feed on other hymenopteran larvae or their food stores.

Stenodynerus, a predatory mason wasp which preys primarily on moth larvae. The mason wasps are not very aggressive and are solitary rather than social, meaning that each female provisions their own nest. On Levisticum officinale.

Stenodynerus on Levisticum officinale

Dolichovespula arenaria, the common aerial yellowjacket. This is a predator which hunts for other insect as protein rich prey for their young. Yellowjackets are social wasps, infamous for their defensive behavior. When they are not near the nest they can be quite docile.

Polistes dominula on Salvia sclarea. A European invader, this paper wasp is one of the few pollinators to be interested in the clary sage in my garden. Despite their nasty reputation (not unlike that of yellowjackets or other social vespids) they are docile when visiting flowers.

Xylocopa tabaniformis on Salvia sclarea. Large carpenter bees like this one are the most conspicuous visitors to the clary sage which has seeded around my garden. This species sometimes has a brownish coat of hair on its thorax, but the one in these photos is entirely black with a coating of pollen. Note that the stigma is in contact with the bees back in this photo.

Xylocopa tabaniformis on Salvia sclarea. Other bees, like carder bees (Anthidium sp.) have been busy on the clary sage.

Xylocopa tabaniformis on Salvia sclarea

Bombus vandykei ♂ on Lavandula angustifolia. The males of B. vandykei are a completely different color than the females. Males are mostly yellow while the females are mostly black except for yellow on their faces and a few bands on their thorax and abdomen. They are particularly attracted to the English lavender.

Bombus vandykei ♂ on Lonicera hispidula, a native honeysuckle.

Machimus sp. with prey on a tomato leaf. Robber flies are predatory and prey mostly on other dipterans and perhaps small hymenopterans or other small flying insects.

Blepharipappus scaber, visited by honeybees and bumblebees in Central Point in one of our apiaries.

Madia gracilis, visited by honeybees and small solitary bees in Ashland in another apiary. The flowers are only open in the morning, like other Madia species.

Apis mellifera with a dusting of pollen on Madia elegans in our Central Point apiary.

Apis mellifera on Madia elegans. M. elegans is a native annual which has flowers that are open in the morning but close as the sun and heat rise. This is an adaptation to prevent the nectar and flower itself from drying up. By the looks of it this is an effective strategy, bees were all over these flowers.

Apis mellifera on Madia elegans.

Madia elegans with plant bugs (Miridae)

Apis mellifera on Trifolium arvense in Gold Hill. This native clover blooms over a long period, yet honeybees seem only marginally interested in it. As other floral sources dry up, I may be seeing the bees work these flowers more and more.

Solitary bee on Coreopsis lanceolata in the garden.

Clockwise from left: Apis mellifera, Bombus vandykei ♂, and an unidentified Bombus sp. on Allium sphaerocephalon

Bombus vandykei ♂ on Allium sphaerocephalon. Male bumblebees are easy to photograph early in the morning or in the evening. Most males don't live in nests, and rather wait by flowers to meet a mate (or several) and ensure the survival of their genes. Therefore, I find them often just clinging to flowers over the course of the night, too cold to move, and thus excellent subjects for photography.

Bombus vandykei ♂ on Allium sphaerocephalon

Bombus vosnesenskii ♂ on Dasiphora fruticosa 'Abbotswood'

Bombus vosnesenskii ♂ on Hyssopus officinalis

Bombus vosnesenskii ♀ on Lathyrus latifolius. Females generally differ from males by having corbicula, or pollen sacks, which the males will not have.

A mated Apis mellifera queen, held by the thorax (and never by the abdomen). I work for a comercial beekeeper, and one of my duties is to catch queens for sale or our own use. Queen honeybees, unlike the working females of most other bee genera, only leave the nest to mate and so do not collect pollen or nectar or anything besides semen. This is on stark contrast to bumblebee queens which in the beginning of their life have to collect food and build a nest before they build up a work force. Bumblebee colonies are usually diminutive with up to 400 individuals while a productive honeybee hive can have upwards of 50,000. Honeybee queens can lay up to 2,000 eggs per day! Think about that.