Pollinator Study

Sunday, October 20, 2013

The Mystery of the Funny-colored Bees

If you have a pollinator garden, after a while you become familiar with the cast of characters that frequent it. That is why one late summer day of 2011 I was mystified to notice that some of the bumble bee guests to my garden were looking kind of strange, colorwise. A species of bee called Bombus vosnesenskii, or, the “yellow-faced bee”, which should have a cream-colored face like this: 


was showing up in my garden with an ochre-colored face, like this:

 
Not only that, but on some of the bees, even the pale yellow stripe on the abdomen was this same orangish color.


My first thought was that it had to be pollen staining. But looking around my garden, I could see no flowers that would stain a bee like that. I thought about any native plants that could cause it, and could come up with nothing. Besides, in looking at the bees, there didn’t seem to be any actual pollen on them, just color.

So I then hypothesized that perhaps the bees were color morphs, meaning insects with a color variation from the norm. Yet I could find nothing in the Bombus vosnesenskii literature that mentioned such a thing. Finally, I considered that these bees could be the result of interbreeding with some other bumble bee species, but again, nothing I read could confirm this possibility.

The summer ended, and with it, the pollinator season. The mystery remained unresolved, a fun riddle that I would occasionally ponder when looking my photos of the “funny-colored bees”.

In late August of the next summer, the same thing happened. Some of the B. vosensenskii coming to my lavender bush had the same weird hue. The mystery deepened in my mind, yet I seemed no closer to finding the truth.

Then in August of this year, some of my neighbors, knowing of my interest in bumble bees, invited me to their garden to see the bees that were “all over our dahlias”. You can probably guess where this is going.

The first thing I saw when I entered their garden was a Bombus vosnesenskii perched on a spent dahlia blossom looking gob-smacked.



The hairs on its face were absolutely loaded with orange pollen. I wondered if the pollen had somehow “jammed its frequencies”, making it unable to function. In that instant I knew I had the answer to my multi-year mystery.

In looking around, a saw several more pollen-stained bees, and the specific dahlia that was causing it. It wasn’t a particularly showy variety, but it did have a few attributes that made it attractive to bumble bees.



First, like all dahlias, it had a composite flower, which means that the centers of the big, daisy-like blooms are actually made up of many tiny flowerets, each of which has a nectar gland its base. Two, this hybrid hadn’t had the nectar bred out of it, or the petals made so numerous that the nectaries were blocked. Three, the pollen on this particular species was particularly thick and plentiful. Pollen is the protein-rich substance that bumble bees gather to feed their larval young.

All good reasons for Bombus to frequent these dahlias, but what these particular bees were after was nectar. And to get at it, they had to stick their tongues and faces deep into the flowers, which put them in contact with the pollen-laden stamens. The effect was similar to sticking one’s face in a bowl full of spaghetti to eat it. Orange pollen was everywhere, staining the bees' hairs.


One of the bees, I noticed, was a very large, beautiful, newly-minted B. vosnesenskii, the hair on her body as sleek and shiny as a black cat’s. She was a next-year’s queen, who would spend the winter in the ground until emerging in the spring to start the subsequent generation of bees.  She was stoking up on dahlia nectar to help her survive the cold, dark months beneath the soil.


No messy eater, she, though. As befits a queen, and with benefit of her long tongue, only the very front of her face, looking like a dainty little powder puff, bore a pale orange dusting of pollen. I was charmed.

I’m always on the lookout for great new pollinator plants, so when I asked my neighbors if I could have a dahlia tuber to plant in my garden, they kindly agreed. With any luck, by next August I will be getting a buzz from watching my own episode of the nature documentary called The Funny-Colored Bees.




 
Here's some additional video of the B. vosnesenskii queen on a dahlia:

 http://www.youtube.com/watch?v=XR-oBFif4jc&feature=c4-overview&list=UUG3jWO8v65u8iJuwiX2blSA











  



Sunday, August 25, 2013

The Pollination Trap

Bumble bees are so cool. One facet of their lives I find most interesting is their interaction with flowers in their role as pollinators. A bee covered in pollen grains is a magical sight to me, but a couple of summers ago I discovered that the floral kingdom can be endlessly inventive in creating methods of insect pollination.

A perennial I really enjoy in my garden is the July-blooming Asclepias tuberosa. A member of the milkweed family, it is also known by the common name butterfly weed. Its thousands of tiny, bright orange, nectar-filled flowers are a trifecta for attracting pollinators – hummingbirds, butterflies and bumble bees all love it. So I was kind of surprised to discover that asclepias has a darker side.

One day a few years ago I was observing a yellow-faced bumble bee (Bombus vosnesenskii) perched on a sneezeweed flower. I noticed the bee was acting strange - stumbling around while frantically trying to groom itself.

When I leaned in for a closer look I saw that its claws were covered with teardrop-shaped flakes of what I assumed to be nectar and pollen. I'd never seen anything like it. I tried to figure out where this weird-looking, sticky pollen was coming from but couldn’t fit the puzzle pieces together So I decided to take some pictures and a couple of videos and send them on to Carol Anne Kearns, a bumble bee expert who wrote the book The Natural History of Bumblebees.

I asked her, "I'm wondering if you have ever seen this before? I couldn't find anything online about it. It kind of looks like the bumble bee is wearing clown shoes. I was trying to figure out which flowers in my pollinator garden were causing this. I think it must be the butterfly weed, because that's what all the vosnesenskii bumble bees are focused on right now. They will nectar from the sneezeweed as well, but they also like to use it as a place to groom, since it's right next to the Asclepias."

Ms. Kearns kindly wrote me back saying: "Butterfly weed produces pollinia - sticky packages made up of many pollen grains, rather than individual pollen grains. That seems to be what is stuck on this bee!
See http://www.backyardnature.net/fl_milkw.htm for a photo."

Pollinia, eh? I’d never heard of it. But now I wanted to find it in an asclepias flower. That turned out to be easier said than done. I went to my garden and harvested a few of the tiny flowers. I tore them apart but couldn’t find any pollinia. Where were they?

I decided to dissect a few more flowers, concentrating on the very base of the blossom. Finally, I found one

No wonder I had difficulty - they’re really tiny – no bigger than Franklin Roosevelt’s nose on a dime! They’re pretty cool looking though – like miniature wishbones.

According to the information that Ms. Kearns sent me, pollinium (plural pollinia) is a pollination strategy that only a few species of flowers utilize, asclepias and orchids among them. From what I’ve seen and read, it can be as sticky as velcro onto a bee’s legs and so resistant to release from the blossom that occasionally a bumble bee will pull its leg off in the struggle to free itself.

There is always something fascinating going on in the pollinator garden, and this year I will again be looking for bumble bees wearing clown shoes. But at least now I’ll understand what it is I’m seeing, and appreciate anew the complex and wondrous interaction between bees and flowers.


Other Resources:

Wiki on pollinium:


Beautiful photo of milkweed pollinium:


Showing how a pollinium is removed from a milkweed flower:


The effectiveness of different pollinators that come in contact with milkweed pollinia:




Sunday, May 19, 2013

The Water Sprites


The Water Sprites

By Nancy Partlow

The first in a series called, “Shoot the Deschutes; Photographing the Fauna and Flora of the Deschutes River Valley and Beyond”

We are so blessed to have a wonderful park in our midst; a park that, thanks to the dedicated work of the Olympia Tumwater Foundation, is experiencing a rejuvenation. English ivy is being pulled and replaced with the native plants species that originally flourished there.  Needed infrastructure improvements are taking place.  I’m beginning to love Tumwater Falls Park again the way I did when I was a child.


But as much as I love the park for its beautiful scenery and nourishment of spirit, there is another who loves it more.  An enchanting and unique little creature, it is North America’s only aquatic songbird – the American Dipper (Cinclus mexicanus).

Also known by its older, more charismatic name of Water Ouzel, the dipper thrives in a beautiful and ever-moving world of cascades and cataracts. Observing it from riverside, this is clearly a being at one with the element in which it abides – cold, rushing water.

I’ve always been aware of dippers at the Falls, but it wasn’t until recently when I sought them out for my Shoot the Deschutes project, that I really got to see them up close.  What I discovered was captivating.


The dipper is a slate-gray bird whose cryptic coloration helps it blend in with the water and weathered basalt of the river.  It is a couple of inches smaller than a robin but larger than the wren it resembles with its short, often-cocked tail.  Compulsively flexing its legs in a bobbing motion reminiscent of deep knee bends, it perpetually genuflects to the river from which it gains its sustenance. My college biology professor once told me that “no one knows why the dipper dips”, and I believe this still holds true.

The dipper makes its living among the rocks and rills of river gorges, hunting for aquatic insects above and beneath the surface of fast moving streams, eating larvae from river bottoms and the undersides of midstream boulders. Fish eggs and small fry are also on its menu.  The toes of its feet are very long, to help it maintain a grip upon the streambed, while the wings are short and stubby to facilitate its ability to “fly” under water.


The water ouzel has a genuine song of “piping notes and trills”, which is loud enough to often be the only avian voice discernible above the roar of the river.

The dipper’s nest is about the size of a football, with a mossy outer shell and an interior cup nest composed of grasses, leaves and bark strips.  According to an article by Dianna Moore of Grays Harbor Audubon, “The female chooses a nest site in the bank along a stream, behind a waterfall or under a bridge."

My recent experiences with dippers at Tumwater Falls Park fortuitously coincided with the fledging of two juveniles from a nest somewhere along the gorge.  I never did discover the nest site, but it was the piercing calls of the babies begging food from their mother that helped me track the trio as they flew in short jaunts up and down the riparian corridor.


The first time I actually saw one of the birds, it was clinging to a near-vertical rock face at the base of the lower falls.  A youngster, its downy feathers dotted with tiny silvery sequins of spray, was watching and waiting for its mother.  The child had obviously been there for quite some time as three small, dead fish were laid out before it, as if on a moss-covered platter.

This bird soon joined its sibling on the Washington State Fisheries barge tethered a few feet away.  From that platform I got a great view of them eagerly propositioning their harried parent for something to eat, excitedly flapping their wings with gaping mouths whenever she drew near.


Though the next day was rainy, I came back to the park carrying a longer-lens camera and an umbrella.  I felt fortunate to witness and film the young dippers exploring their brand new world of the upper estuary.  I admired their mother's swimming skills, as she zigzaged at lightning speed beneath the rippled waters tracking and catching small salmon (very kindly just released by Fish and Wildlife into the estuary). She then rapidly knocked the stunned fingerlings upon the river cobble before stuffing them down the babies’ gullets.
On my third visit, I was standing on the wooden footbridge bridge directly over the lower waterfall when a group of students from the Raymond School District showed up.  I had been following the dipper family around the middle falls, then back down to the estuary.   But now, the ouzel chicks seemed perilously perched on a large fallen tree wedged directly above the roaring torrent.  I pointed out the birds to the students, who were enthralled but worried about the babies.  Yet the mites seemed entirely at ease and unafraid.  Mama soon came and fed them, and once again they all moved on.


A dipper’s habitat requirements include the clear, clean, well-oxygenated water that supports its favorite prey.  So, I wonder, how do dippers cope with the raging and silt-laden Deschutes during our periodic great storm events?

Dippers are uncommon residents of Thurston County and elsewhere in their range, which stretches from Alaska, throughout the U.S. and Canadian mountain west and into Central America. Other than Tumwater Falls Park, the only other place in Thurston County that I know they occur is within a picturesque gorge in the upper Deschutes watershed, where a water ouzel was once seen flitting along the rim of a large waterfall.


It seems somehow fitting to me that these marvelous little birds safeguard both ends of the Deschutes.  That these evanescent water sprites, slipping easily between the realms of fluid, air and earth, at once keep the river’s secrets, yet reveal its hidden beauty to any one with the eyes to truly see.

  
Addition Resources:

Videos:

A short video of adult feeding a juvenile at Tumwater Falls Park:

Some great videos of American dippers pulled off of YouTube:

American dipper building nest at Whatcom Falls: https://www.youtube.com/watch?v=HtpVi3fWnfU

Dipper adults feeding babies in nest on Dosewallips River, Olympic Pennisula: http://www.youtube.com/watch?v=j8bkjt6gQy0


American dipper swimming under water: http://www.youtube.com/watch?v=cV6IDY1TSC0

Dipper diving into roaring river: http://www.youtube.com/watch?v=sfkGvKEeqVM




Wednesday, February 27, 2013

Mima Mounds


Mima Mounds Prairie
March 2012

The Mima prairie sprawls out in front of me,
 snagged in the feet of the Black Hills.
Late winter winds shear off the iced hills,
swirling restlessly around the mounds.
In my mouth the metal taste of snow.

On the prairie, last year’s bunch grass:
stiff hollow stalks rattle together like sabers.
Cold creeps up my back

Greening mats of kinnick kinnick carpet the mounds
Tiny flower bells emerge from clots of lichens
Faint pink flash of bloom tantalizes my eyes.

Soon enough, the sun will return:
the hot breath of summer and the smell of vernal grass
sweet-baked in the heat.
Now, the west wind sings a chilly dirge to the Mima Mounds.
Deep in the soil, the shooting stars sleep.

Poet's Shooting Star wildflower



Janet Partlow
Resources:
poem by Janet
Mima prairie photo by Nancy Partlow