Monthly Archives: September 2012

Plight of the Bumble Bee Part V: What I’ve Learned

Time to wrap up my Bombus segment. I hope that you enjoyed reading about the bumble bees and maybe even learned a couple things. I certainly did. A quick recap, a la “what I have learned:”

1. Our Southern Neighbors

In Plight of the Bumble Bee Part III: Not-So-Impossible-Giants, I posted this photo of a beautiful bumble bee I saw on a trip to Patagonia:

La Gigante Imposible (c) 2012 MRS

 

I mentioned that, while I was sure this bee was in the genus Bombus; (the bumble bee genus), I didn’t know which species it was.  Well just last week I stumbled across an article (incidentally also titled Plight of the Bumblebee so I guess I’m not as clever as I thought) that says there is only one bumble bee native to Patagonia, Bombus dahlbomii. This bee is the largest bumble bee in the world.

Our poor Southern neighbor appears to be suffering from similar issues to her North American cousins (see my post The Plight of the Bumble Bee Part IV: Pandora’s Bee Box, as described in this Science article.

2. Tricky Bee ID

The Mystery Bee Among the Blossoms

I was very flattered to receive a site visit from the highly esteemed Robbin Thorp of UC Davis, who happens to be the bee identification guru. He informed me that the conclusion I drew from my Is it a bumble? quiz, that the bee in question was most likely Bombus impatiens, was incorrect, and that the mystery bee was actually a male Eastern Carpenter Bee, Xylocopa virginica. The reason that the bee did not have any scopae (pollen collecting hairs) was because this individual was, in fact, a male (see The Dastardly Deeds of Male Bees, and while the male Eastern Carpenter Bee is often mistaken for the Common Eastern Bumble Bee, Bombus impatiens, certain aspects of the leg morphology can be used to tell them apart (for those of you keeping score, the hind tibia is swollen and shorter than the basitarsus).

In this blog, I will probably not be able to give positive identifications to a lot of the live bees I photograph. This is because I am still learning how to identify bees, and even for bee identification gurus, much of the time bees are nearly impossible to identify on the wing (the specimen must be taken for examination under a microscope). So I am always grateful to those wiser than I who are around to correct my mistakes. Thank you, Robbin Thorp!

Tune in next time for more photos of bees, large and small.

Diadasia My Dear

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(c) 2012 MRS

A small aside, I just wanted to mention that I have finally updated my header photo. Instead of showing an admittedly photogenic Halictus tripartitus, truer to form this bee is a titular Diadasia species. This particular bee is Diadasia enavata just finishing a visit to a native sunflower (Helianthus bolanderi), which is fitting since Diadasia enavata are sunflower specialists, meaning they only visit sunflowers for food.

The Plight of the Bumble Bee Part IV: Pandora’s Bee Box

Nate Pope, Bee Biologist Extraordinaire

Illuminated by a single red light, Nate bent over the open cardboard box, alternately counting objects with a clicker and manipulating objects with gloved hands holding a long pair of tweezers. A swelling chorus of low buzzing made me more than a little nervous. Even though I knew that the  contents of the box couldn’t escape, I kept seeing phantom angry, swooping objects in the darkness.

In the above photo, Nate is removing pollen stores from a bee nest to see how much they ate this week (thus the gloves, long tweezers, and angry buzzing). Bees’ eyes are not designed to see red, so Nate works under red light to keep the bees from flying away when he opens the box.

From the title of the post, you’ve probably guessed what kind of bees Nate is studying.

Bombus impatiens colony. Please excuse the poor photo quality!

This is a domesticated colony of the Common Eastern Bumble Bee, Bombus impatiens. It is the most common bumble bee encountered on the east coast of North America from Ontario, Canada to Florida, USA.

By far the largest colony member, the queen perches protectively over a profusion of pots in which food (pollen and/or a thin watery honey) is stored, and larvae are raised. The queen is surrounded by smaller worker bumble bees. Bombus impatiens typically build underground nests.

Alternative Pollinators

(c) David Besa 2005

Despite their widespread use as agricultural pollinators, honey bees are often surprisingly bad at their jobs compared to native bees. Tomatoes, for example, require sonication, or buzz pollination. This involves producing large vibrations to shake pollen free from pollen-holding structures in the plant: something that bumble bees do quite well, but honey bees cannot. Farmers that grow tomatoes in greenhouses can therefore purchase colonies online, which are shipped via snail mail in cardboard boxes. The bumble bees are released in the greenhouse to pollinate their tomato plants to ensure a robust yield.

The Dark Side of Globalization: Tiny Smallpox Blankets

Most of us Americans have heard stories in school about the introduction of smallpox by European settlers the Americas. Although the European settlers had some natural resistance to the disease, the indigenous peoples of the Americas, who had never encountered the disease, had no immunity. The disease ran rampant in these communities, killing millions.

Parasitic mites, such as these tracheal mites infecting the air passages of a honeybee, can be spread from one bee to another similarly to pathology in humans.

In the past decade, bumble bees have also been in in decline in the Americas. Although there are multiple causes for these declines, including habitat destruction and agricultural pesticide use, diseases transported along with Bombus impatiens colonies used for greenhouse pollination are a major culprit. Many of these bees are raised in the Old World, where they pick up diseases such as tracheal mites (bugs that live in the bee equivalent of lungs) and transport them to the New World. New World bumble bees have not evolved defenses to these diseases because, like the indigenous peoples of the Americas, the bees have never been exposed to them before. Tragically, once these diseases get out of the bee box, it is almost impossible to reverse their spread through native bee populations.

Bombus franklini, photo courtesy of Robbin Thorp. Click the picture to view the Red List Profile.

One of the casualties of the bees-in-a-box is Bombus franklini, a species discovered by UC Davis Professor Emeritus Robbin Thorp. Thorp’s research showed that from 1998-2006, sightings of B. franklini decreased drastically. Only one bee was sighted in 2006, and as far as I know, there have been no more sightings of Franklin’s bumble bee since.

For more information on how to help our sisters the bumble bees, please check out the Xerces Society’s Bumble Bee Conservation Initiative.

Small Bees, Huge Bees, Green Bees, Blue Bees (Part I)

Well, it’s been a busy summer, but some kind words of encouragement convinced me to start posting to my bee blog again. I think, to get warmed up, I’ll just post some photos I took over the summer that encompass some of the many sizes and colors different bees come in.

Although many bees are yellow and black striped, some come in beautiful hues. Take this bee I saw in Tahoe National Forest this August:

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Green Bee on Wyethia angustifolia (c) MRS 2012

I don’t know what species of bee this is since I didn’t collect it to key it out, but it was a beautiful green metallic color with pink undertones.

The most common green bee that I encounter here on the West Coast is Agapostemon texanus, the green metallic sweat bee. The females are entirely green, while the males have a black and yellow striped abdomen. Here’s a beautiful photo of a male Agapostemon texanus from wikipedia.org:

 

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Agapostemon texanus, from Maricopa Co., Arizona, USA.