Why do Butterflies Gather on Sandbanks?

07 November, 2015 5 comments Leave a comment

Last June, during our trip to British Columbia, I photographed these male Tiger Swallowtail butterflies on a sandy beach on a lake in northern Ontario. They stayed in the same spot for at least an hour, while we had a picnic lunch close by. At the time, I wondered what phenomenon kept them there in one spot for so long. Read on to the end of this article to find out the answer.

This fall, I taught a two-day watercolour workshop 'Butterflies on the Beach', using these reference photos. I began by masking off the paper margin and the butterflies with self-adhesive contact paper and drawing gum (masking fluid). Using a toothbrush, I spattered on lots of drawing gum, which forms a temporary, waterproof coating in the shape of small pebbles.

Then, using several mixtures of primary colours (Raw Sienna, Permanent Alizarin Crimson, and Indigo), I spattered on paint, sprayed on clear water, and tilted the paper to make some areas soften and run together in a cool, sandy colour. Once the paper had dried, I wiped the paint off of the plastic mask so I could take the photo below.

I peeled the plastic mask off of the butterflies and stuck the pieces onto the margin, in case I needed to re-use them. I removed all drawing gum from the sand background, to reveal white paper in the shape of small stones and large grains of sand.

Using the same primary colours mentioned above, I painted the butterflies with a pale yellow layer, let it dry, and masked out the intricate dots of light colour on the outside edges of the butterfly wings. When the masking was dry, I painted the black details over top. Then I painted in the shadows cast by pebbles and butterflies, as shown below.

To complete the painting, I removed all masking from the butterflies, added bits of blue and red dots on the wings, and bry-brushed in the details on all the little stones. Below is  the finished painting, with an integral margin. When mounted and varnished, the margin resembles a mat, such as one would use when framing with glass. The title is 'Sunbathing Swallowtails'.

Sunbathing Swallowtails (watercolour, framed size 19.5"h x 25.5"w)

Below is a detail of some of the butterflies.

Now, why do male butterflies gather at sandbanks, you ask? Apparently they are ingesting sodium and nitrates, often found in mud or damp sand. This process is commonly called 'mud-puddling', and is vital for digestion, reproduction, and flight. Who knew?

Click here for more information about the finished painting.

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  1. Lesa Robertson January 22, 2016

    What a lovely painting Karen and I enjoyed your inspiration story as well.

  2. Anne Sims January 21, 2016

    Lovely, Karen! Enjoyed the story of how this work originated.

  3. SHARYN YATES January 20, 2016

    Beautiful work as always. Still love my “Doors of Port Perry”.

    Hope you and John are enjoying good health.

    Take care

  4. Margo McLean January 19, 2016

    looking forward to classes whenever you start….. also happy birthday

  5. Helen Smith November 07, 2015

    Absolutely incredible painting!