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Canadian Tiger Swallowtails Puddling

In April, during mud season, living on a dirt road can be a curse.  But in May and June, when swallowtails emerge, it can be a blessing as you often witness a phenomenon called “puddling.” This phenomenon consists of clusters of butterflies (predominantly males) gathering to obtain salts and minerals that have leached from the soil into standing puddles and moist dirt.

Because butterflies do not have chewing mouthparts they must drink their meals. While nectar is their main source of nutrition, males often supplement their diet with minerals. The sodium uptake aids in reproductive success, with precious nutrients often transferred from the male to the female during mating. This extra nutrition helps ensure that the eggs survive.

Pictured are Canadian Tiger Swallowtails puddling.  They are easily mistaken for Eastern Tiger Swallowtails as they look very much alike and their ranges overlap. To determine which you have seen, look at the underside of the butterfly’s forewing and see if the yellow band along the margin is solid and continuous (Canadian Tiger Swallowtail, Papilio canadensis), or if it is broken up into spots (Eastern Tiger Swallowtail, Papilio glaucus).

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6 responses

  1. Alice

    Actually, I learned about ‘puddling¡ from you, Mary, in a previous post. Fun to see that many butterflies.

    June 3, 2020 at 8:23 am

  2. Diane Alexander

    Did you get a frost on Sunday night? We got close, but not quite. Last night it was in the 50’s. Sheesh! Wendy thinks I should form a protest group here in Winchendon. I don’t have a clue how to do it. Lots of protesting going on in SLC. They are under cerfew every night from 8PM-6:30AM until Monday. Then what will happen on Monday? The country is in turmoil. Rightly so I think. I definitely support the rebellious movement. Things have got to change.

    Will call you soon. XOXOXOXO you. Di

    June 3, 2020 at 8:54 am

  3. Pat Thomas

    thanks for making the day shine, mary. we have canadian tiger swallowtails in duluth. it’s very special to see them puddling. spring is in the air

    June 3, 2020 at 9:36 am

  4. Alan Keitt

    Puddling – Reminds me of similar behavior in Spring thaw when we were wearing galoshes with large buckles and perforated clasps. We managed to get our feet wet anyhow. Great sport

    June 3, 2020 at 11:15 am

    • Hi Alan! I LOVED my black galoshes, and snapping those buckles! I wonder if they still make them! Am about to head to a retirement place here in VT — tell me I’ll survive it!

      June 3, 2020 at 5:15 pm

  5. I’ve seen this in my backyard, usually three or so in a bare spot (now getting overgrown). Years ago, after a huge storm on Lake Huron, I was walking on the beach. Weeds had been rolled onto the sand. They were simply teeming with monarch butterflies; I suppose doing something similar.

    June 3, 2020 at 11:45 am

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