Ruby-throated Hummingbirds love red flowers. In my garden, they particularly like the Cardinal Flower, which sends up 4 foot tall stalks with a bright red plume of flowers that develop sequentially from bottom to top of the stalk over a 4-6 week period. Apparently, it produces some really good nectar too, because it is the first flower they visit in the morning.
Sometimes the probing is just a test to see what might be there, as the bird tastes with the tip of its tongue.
When there is sufficient nectar at the base of the flower, hummingbirds hover for several seconds in place while they mop up every drop. In this case, the bird’s head almost disappears into the flower as it inserts the bill all the way in.
The bill of the Ruby-throated Hummingbird is the perfect size and shape for this flower. When it dips its bill deep into the base of the flower, the top of its head brushes a fringe of anthers which deposit pollen on the surface of its head feathers. Later when it visits a different flower, perhaps on a different plant, the pollen will be rubbed against that flower’s stigma, adhering to the sticky surface. If it is the right type of pollen, it will germinate and a pollen tube will grow down the stalk supporting the stigma (the style) into the ovary. Sperm can then leave the pollen grain, swim down the tube, and fertilize the ova to begin the process of seed production.
Hummingbirds don’t care which flowers deposit pollen on their head, but the plants want to ensure that a particular flower receives pollen from a different individual (i.e., avoid self-pollination). To maximize the potential for out-crossing, Cardinal flowers develop the male parts first — promoting pollen donation, and after a few days, the style and stigma emerge to protrude beyond the anthers — promoting pollen reception.
Coevolution of cardinal flower structure and Ruby-throated Hummingbird sugar appetite has made this system a perfect fit for both.
Those are fantastic shots. I’ve never met a cardinal flower in person, but I’ve seen plenty of hummingbirds. They come here because of the hosta blossoms.
Oh that’s interesting. I have lots of hostas (some with flowers the deer haven’t eaten yet), but haven’t watched for hummingbirds on those. Supposedly cardinal flowers like damp places (like the giant lobelia), so I expect you have them there too??
Yes, I have over 200 hostas in the yard and hummingbirds seem to love them. I haven’t seen any yet this year but they’re usually always around. We have cardinal flowers here and they grow near streams and rivers but I have a lot of trouble seeing them because of color blindness.
It seems strange that you have so much snow and them have hummingbirds in your garden in the winter. They are such exotic beautiful birds.
Unfortunately, no hummingbirds will stay here in the winter. (There are few bird species that stick out winter in Minnesota!) The hummingbirds will leave pretty soon for parts of Mexico, Central America, and the Caribbean. It’s amazing to think that this tiny little bird can migrate thousands of miles, sometimes clear across the open water of the Gulf of Mexico to northern South America.
Wonderful post, Sue, with lots of great photos and information. Earlier this summer I looked carefully at the cardinal flowers when I photographed some tiny bees on them and read that hummingbirds pollinate the flowers. I couldn’t visualize how they accomplished that and your photos make it easier to understand now. The hummingbird shots are amazing–your time in the blind definitely paid off.
Thanks, Mike. Yes, time well spent, even if it was a very sweaty time. I think bees are better suited to the giant blue lobelia, which has a much shorter floral tube. I haven’t tried photographing them yet. Thanks for the idea.
I had read on-line that hummingbirds were the only pollinators for the cardinal flower, but I got some shots of a tiny bee covered in pollen from what I think were the male parts of a cardinal flower. It seemed to me that a “normal” sized bee would have been too big.
Interesting! Did you post any shots of that bee? I think the bee might be able to receive the pollen OK, but it might not be big enough to deposit it on the stigma when it elongates beyond the anthers.
I posted them here http://michaelqpowell.wordpress.com/2013/08/12/tiny-bee-on-cardinal-flower/. The more that I read about cardinal flowers, the more I was confused about what this little bee was doing.
Oops, I accidentally replied to this on your blog instead of mine…brain dead tonight.
Absolutely spectacular photographs Sue! And a remarkable example of symbiosis and timing.
Thanks, Finn. You have to love it when nature makes it work so perfectly.
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Excellent photos. Thanks for sending me the link! It looks like it was well worth the sweat!
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