Wednesday, January 11, 2017

Two Ice Observations

Friday and Saturday nights were two of our rare Austin area hard freezes, with the temperature getting down into the low 20s. (As I write this on Wednesday evening it's already back up in the 70s!) On Sunday morning I birded the east half of Lake Creek Trail and made a couple fun observations involving ice.

By the pond formed by the last dam on Lake Creek I ran into Steven McDonald and we remarked on a very thin layer of ice covering over half of the water's surface. Steven spotted a Yellow-rumped Warbler hopping (and occasionally sliding) around on it, very actively foraging. Later we spotted another, along with a Ruby-crowned Kinglet and a Common Yellowthroat, all hopping around on the ice. I've never seen this before and really enjoyed watching them. I'm guessing these birds were foraging for insects, although I wish I knew for sure since it seems like it would be too cold to find any. All of these birds weigh about half an ounce, light enough for this very thin layer of ice to support them. Here are a few photos I got of the original Yellow-rumped Warbler on the ice:

Yellow-rumped Warbler on Ice - 2

Yellow-rumped Warbler on Ice - 1

Yellow-rumped Warbler on Ice - 4

In the strip of woods along the north edge of the pond I discovered another ice-related natural phenomenon. Frostweed (Verbesina virginica) is a common native shrub that favors shade and blooms in the fall. Its clusters of white flowers are very valuable to pollinators, including migrating Monarch butterflies. So why is its common name "frostweed?" After it has died off in the winter, a hard freeze will cause the bases of the stems to split open and water and sap will ooze out the cracks to form thin ribbons of ice in interesting shapes. There were a few patches of frostweed in this patch of woods and just about every plant had "bloomed" into an ice sculpture! Here are a few photos:

Frostweed Ice - 1

Frostweed Ice - 2

Frostweed Ice - 3

Frostweed Ice - 5

Frostweed Ice - 6

Look for frostweed after our next hard freeze!

It was also fun to see some returning wild ducks on the creek and on the Parmer Village Pond. Here are some American Wigeon that were on the pond. What a beautiful bird!

American Wigeons - 1

Here's my complete bird list.

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