Gardening for Wildlife Makes a Positive Impact

Western tiger swallowtails (Papilio rutulus) have been a steady presence in our garden for the past five weeks or so. It used to be that I would feel lucky to see a single one briefly in an entire summer, but now it’s rare to step outside or glance out the window and not see one. This is an encouraging sign that gardening for wildlife—even one yard—can and does make a difference!

Western tiger swallowtails only live 6-14 days in the adult butterfly stage, and during this time they lay eggs on the underside of host plants such as aspen, alder, ash, and willow. Our Scouler’s willow (Salix scouleriana) is the size of a small tree now, and I suspect they are laying eggs on it, meaning we have a regular stream of adult butterflies in our yard! They seem to favor showy milkweed, fireweed, and showy fleabane. I feel so grateful to have a six-year pesticide-free yard where they can breed and complete their life cycle. Even our neighbors have been commenting on the rise of butterflies this year, though they mistakenly think these are monarchs. 😊

Building habitat where western tiger swallowtails can thrive requires their host plants, a mineral source (consider a drip system into a pan of sand), a food source (native species are best for high-quality nectar and preference of the species to feed on plants with which they evolved), canopy layers for shelter, and discontinuation of pesticide use. It’s taken six years to see western tiger swallowtails thrive in our yard, so remember that it takes time in certain areas where habitat destruction and fragmentation have been occurring for 150 years for wildlife to build populations up again. We can do this—one yard at a time! ✨