Western Tiger Swallowtail – Papilio rutulus
The western tiger swallowtail, a common butterfly, gets its name from its vibrant black and yellow wings that resemble tiger stripes. This species is found all the way from British Columbia to southern New Mexico. Western tiger swallowtails prefer to live in woodlands near rivers and streams, but you can find them often in wood suburbs, parks, roadsides, and your backyard! 

July is the perfect time to spot the tiger swallowtail because it is seen most often throughout summer. Keep your eyes open in your garden or at your local park as its life span is only between 6 to 14 days long. Western tiger swallowtail adults eat nectar from a variety of plants which include thistles, California buckeye, zinnia, and many others. The species of butterfly help contribute to native plant pollination.  

The tiger swallowtail adults lay green, glossy round eggs one at a time, some adults will lay up to a hundred individual eggs. Each egg is laid on the underside of the leaves of host plants. The common host plants for this swallowtail are willows, aspens, ashes, alders, and cottonwoods. Once the caterpillar emerges from the egg, it will feed on the leaves of these trees.  
Each swallowtail caterpillar will molt five times and reach five centimeters in length. After the series of molts, the caterpillar will become a pupa, the stage before becoming a butterfly. During the summer a butterfly can emerge after just 15 days but in colder months the butterfly will not emerge until warmer weather, usually in spring or early summer.  

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Western Tiger Swallowtail