Yesterday, Birds at the Burke, was a wonderful experience for anyone with the slightest interest in birds. If I understood correctly the Burke has the largest collection of bird specimens in the world, which is an incredible research opportunity and within walking distance of Union Bay.
It would be impossible to say which guest speaker was the most interesting. However Tom Daniel's presentation about how birds fly was especially memorable. In particular the hovering hummingbird presentation. It turns out that the hummingbird's wings are actually more similar to our wrists and hands rather than our shoulders and arms. This allows the hummingbird to turn the wing over at the end of each stroke. Which means that regardless of whether the stroke is forward or backward it provides lift. In other words there is no wasted return stroke, both directions are power strokes. If you hold your hands out and up to each side of you body, with your elbows against your sides and then trace horizontal figure eights in the air you will be imitating the motion of the hummingbird's wings. If you where a bit lighter, with feathers instead of fingers, you would be hovering at this point. :-)
One of the questions asked during my presentation was how do woodpeckers know when there are insects inside of trees. This morning's research of the web provided a number of alternative options. Which included:
- Watching insects, like ants, traveling into the tree,
- Seeing holes the insects make to get into the tree,
- Being able to hear the insects moving about inside the tree (widely accepted),
- Drumming on the tree to hear if it is hollow which indicates insects have been here.
This discussion centered around Elvis and some of his work last winter. Still the following photos of a female Downy Woodpecker (DW), seen last week near last spring's nesting spot, show a similar method for finding food as well. Note: Cornell says that the female DWs are relegated to searching the trunks and larger branches when a male DW is present. Curiously if you look at the branch sizes in the last springs photos you will see the male prefers to find food on the smaller branches. He is seen on the tree trunk only when he is returning to the nest, usually with food.
In any case as you look at these new photos see if you get the impression that the female DW is searching for food using the Stop, Look and Listen technique.
Also of interest is the natural camouflage of the DW.
The feet nearly disappear. The spots on the back look similar to the bright spots on the trees bark and the coloring on the back of the head makes the shape of a head difficult to pick out.
Even up close the "camo" is still fairly effective.
Looking for food in all the right places.
Finally when the DW reaches the top of the snag the search begins for the next best tree.
If you missed Birds at the Burke this year you should make a note to watch for it next year. There were lots of activities for children as well. Including getting to hold and touch bird specimens, draw birds with the guidance of excellent illustrators and a host of expert birders who were all happily sharing their knowledge.
Have a great day on Union Bay...where nature lives in the city!
Larry
PS: In the previous post are 20 pictures of mostly common birds found around Union Bay. If you have not taken the challenge you could time yourself to find out how long it takes you to determine all 20 types of birds. Feel free to post your time in the comments section. For birders you should also note the gender of each bird in the photos when possible. For master birders please help point out the age of the birds when possible. Good Luck!
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