Thursday, June 25, 2020

Eastern Tiger Swallowtails: Wings of the Woodlands

The eastern tiger swallowtail lives in deciduous woods along streams, rivers and swamps and can be seen flying along the roadways here in the Mountains. Eastern tiger swallowtails are loners but are known to be quite friendly to humans and have been observed following people around their yard or in Fields.  

Males are yellow or yellow-orange with black tiger stripes. Their wings are bordered in black with yellow spots, and there are black “tiger stripes” running across the top of their wings. Their long black tails have blue patches on them.

Females can range in color from the yellow of the male to an almost solid bluish-black. The black form of the eastern tiger swallowtail is most common in the southern part of its range in areas also inhabited by the pipevine swallowtail, a butterfly that has an unpleasant taste. The black form of the eastern tiger swallowtail may be an example of deceptive coloration using mimicry by pretending to be the poisonous pipevine.

Males will fly from place to place looking for a mate and will only mate once in a lifetime. After mating the Male butterfly will continue bouncing from flower to flower, pollinating until he expires. 

The Females lay single green eggs on the leaves of woody plants and have the ability to lay 200-430 eggs, at a rate of about 30-50 per day. The eggs will turn a dark gray just before hatching, which takes about 10-13 days.  Once hatched the larvae eat the leaves of a variety of woody plants including wild cherry, tulip, birch, ash, cottonwood, and willow and can be found on fennel in your garden.  The caterpillar is brown and white when it is young, but it changes as it grows older.  When the eastern tiger swallowtail caterpillar matures it is green with orange and black false eyespots. The eye spots are a type of deceptive coloration that helps protect the caterpillar from predators. Predators see the eye spots and think that the caterpillar is a much large animal than it really is! These caterpillars look more like stubby snakes, complete with a fake green head, faux black and yellow eyes, and an orange, forked fleshy antennae which remain inverted at the top of the head but can evert, expand, and move, releasing a stinky substance in the process. After reaching the 5th instar (about 3-4 weeks old) the last stage before pupating, the caterpillar will climb to a high location, affix itself with a string of silk and form a J- position.  This is a sure sign the butterfly will pupate within 24 hours.

The Pupa or Chrysalis stage lasts 10-20 days.  When the chrysalis becomes clear, the adult butterfly is about to emerge and begin another generation. It completes its life cycle (from egg to adult butterfly) in one month and as an adult butterfly usually lives another month.

This process continues until cold weather begins to set in. This large, yellow butterfly does not migrate. It spends the winter in the chrysalis stage.  As Fall sets in, the longer nights and cooler temperatures will trigger the caterpillar to become a chrysalis and wait until spring to emerge.  The adult emerges in the spring after sufficient warmth, usually about the same time that lilacs bloom and the new year generations begin.

As adults these butterflies eat the nectar of flowers from a variety of plants including the butterfly bush, milkweed, Japanese honeysuckle, phlox, lilac, ironweed, and wild cherry.  Unlike bees, butterflies are highly attracted to red blooms.  The brighter the flower the more pollinators like Eastern Tiger swallowtails will be observed.

Having long legs and a proboscis, or feeding tube, a butterfly’s body may never actually touch the flower it’s resting on. But its wings still brush against and collect pollen, especially when hanging onto down-facing blooms. Pollination happens when this butterfly gently brushes its pollen-covered hindwings against the stigma — the flower’s female organ that receives pollen thus giving the plant a chance to reproduce itself.  Some plants have a structure where the anther (male) and stigma (female) parts are widely separated, leaving the chances that a small bee could come into contact with both parts to spread pollen extremely low. However, the swallowtail with its wide wingspan (3.5 to 4.5 inches) can reach both parts of the flower, therefore becoming the main means of pollination for particular plants such as the flame azalea.

How to help

If you want to help these beautiful pollinators and witness their presence:  Here are six things you can do:

  1. Ditch the pesticides.  Pesticides, particularly malathion, Sevin, and diazinon, will kill butterflies.  One of the best and most natural ways to make pesticides at home is salt spray. In fact, not only does it help deter pests, it will also help increase nutrition absorption like magnesium and help plants take up vital nutrients like phosphorus and Sulphur. You can add some salt in water and stir the solution well. Add it into a spray bottle and sprinkle on the plants. You can also sprinkle salt around the base of your plants, reapplying every week.
  2. Grow native plants. Growing native plants in your garden is akin to supporting your local farmers markets. It’s better for the planet, provides you with the easiest to care for crops, and it will support pollinators like butterflies and other local fauna that have evolved with the local flora.
  3. Keep the sun in mind. Even if you have just a small patch of land or a balcony, if it gets good sun, you could help support butterflies. There’s a reason we often associate butterflies with gorgeous sunny days; they typically only feed in full sun.
  4. Plant the right colors. Butterflies like bright colors. Think red, yellow, orange, pink and purple. And make sure the blossoms are flat-topped or have short flowering tubes.
  5. Plant the right milkweed. Monarchs only eat from the milkweed plant. But did you know that there are many types of milkweed? If you plant the wrong one for your region, it might not do monarchs any good.  You can find the right milkweed for your local butterflies online.  In the Adirondacks swamp and common milkweed are most utilized by Monarchs.
  6. Create butterfly spas.  Butterflies prefer to rest in full sun, so nice flat rocks, for them to sun on will bring these gorgeous creatures to your yard. They also love puddling, which is basically hanging out in damp sand or mud where they drink a little water and mineralize. You can create specific puddling spots for the butterflies by filling shallow dishes or pans with sand and a bit of water and placing them in sunny spots in your yard.

Beneficial plant pairings

The following plants are recommended for these common butterflies:

  • Alcon Blue – buckwheat, lupines, milkvetch
  • American Painted Lady – cudweed, everlast
  • Baird’s Swallowtail – dragon sagebrush
  • Black Swallowtail – parsley, dill, fennel, common rue
  • Coral Hairstreak – wild black cherry, American and chickasaw plum, black chokeberry
  • Dun Skipper – sedges, grasses including purpletop
  • Eastern Tiger Swallowtail – wild black cherry, ash, tulip tree, willow, sweetbay, basswood
  • Giant Swallowtail – prickly ash, citrus, common rue, hoptree, gas plant, torchwood
  • Gray Comma – gooseberry, azalea, elm
  • Great Purple Hairstreak – mistletoe
  • Gulf Fritillary – maypops, other passion vines
  • Henry’s Elfin – redbud, dahoon and yaupon hollies, maple-leaved viburnum, blueberries
  • Monarch – milkweeds
  • Painted Lady (Cosmopolite) – thistles, mallows, nievitas, yellow fiddleneck
  • Pygmy Blue – saltbush, lamb’s quarters, pigweed
  • Red Admiral/White Admiral – wild cherries, black oaks, aspens, yellow and black birch
  • Silver-Spotted Skipper – locusts, wisteria, other legumes
  • Spicebush Swallowtail – sassafras, spicebush
  • Sulphurs – clover, peas, vetch, alfalfa, asters
  • Variegated Fritillary – passion flower, maypop, violets, stonecrop, purslane
  • Viceroy – willows, cottonwood, aspen
  • Western Tailed Blue – vetches, milkvetches
  • Western Tiger Swallowtail – willow, plum, alder, sycamore, hoptree, ash
  • Woodland Skipper – grasses
  • Zebra Swallowtail – pawpaw


You can make a difference in the life of a Butterfly!

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Jackie Woodcock was born and lives in the Adirondack Mountains. She is an apiarist, lepidopterist, conservationist, teacher, writer, artist, and a co-owner of SkyLyfeADK. You can find her SkyLyfeADK on Instagram and Facebook.

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