Hoary Commas: Woodland Butterflies at Yosemite and Tahoe

Commas, members of the family of butterflies known as the Brushfoots, are typically woodland butterflies.  I've seen several Hoary Commas (Polygonia gracilis) fluttering about Sierra Nevada woodlands recently, and always stop to admire them.  Many species of commas rarely feed on flower nectar, instead obtaining nutrients from tree sap, carrion, dung and mud.  The Hoary Comma, found predominately in the mountains of the western part of the North American continent, is more likely to visit flowers than other species of commas. 

 
The main larval foodplant for the Hoary Comma is currant (Ribes spp.), and eggs are laid on petioles (leaf stems) and the undersides of leaves.  Hoary Commas have a lifespan of about one year.  Breeding takes place in the spring, and eggs hatch in the summer.  Commas overwinter as adults by hibernating during the winter, often in the cracks and crevices of logs and trees, and may emerge to fly on warm days.  Once the weather warms up in the spring, they emerge to breed and the cycle is complete.

The underside of the Hoary Comma's wings provide excellent camouflage as they hibernate in
cracks in logs and trees. 

Comments

  1. Alastair DriverJuly 18, 2019 at 2:00 PM

    Hi Siera, I have stumbled across your great blogspot in my early attempts to identify various bird, mammal, insect and wildflower species from my memorable visits to Yosemite NP over the last week. I am a lifelong keen naturalist who has had the pleasure of working as a professional conservationist in the UK for 40 years now. (I was national Head of Cosnervation for the Environment Agency and now I am the Director for Rewilding Britain amongst other things. Like you, I suspect, I always want to know what species I am seeing and photographing. Would there be any chance of me sending a few images to you for verification of id ? If so please could you email me at ali@sonningdrivers.plus.com
    Many thanks Prof Alastair Driver

    ReplyDelete
  2. Siera NystromJuly 22, 2019 at 11:47 AM

    Hello, Prof. Driver! Thank you for your kind words. I'm so glad you were able to visit Yosemite and that you found my blog was useful! I've sent you an email.

    ReplyDelete

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