Thoreau's Legacy by Richard Hayes Page B

an eastern black swallowtail. Watching this unexpected guest pull an anise blossom to her mouth and eat, I remembered a friend’s question: “Where are the butterflies this year?”
    Our high-desert yard and kitchen garden usually attract five species of swallowtails, plus monarchs, sulfurs, painted ladies, fritillaries, western whites, and common blues. Anise swallowtails are normally so abundant that I plant extra anise in order to feed the plump caterpillars.
    But not this year, when every butterfly has been cause for remark. Until this accidental houseguest, in fact, I hadn’t found a single swallowtail caterpillar in the garden. My plants had flourished unmunched.
    What has changed? After a decade of increasing drought, this year’s weather patterns oscillated wildly, bearing out the predictions for global climate change in our region. First came a winter snow pack so abundant that it broke records, and then nothing: no wet spring snow, no summer rain until it was too late to do any good.
    Watching our caterpillar houseguest chew another flower, I counted out the weeks and calculated that she would metamorphose just in time for winter, tricked by abnormal weather.
    Over the next few weeks, Gluttonous ate her way steadily through the anise bouquet, growing larger and plumper by the day as autumn flared gold outside the windows. One morning she slung herself under a branch of anise, held by her stumpy pairs of hind legs and one glistening strand of white silk. Forty-eight hours later, her striped skin had hardened into a pale green chrysalis. The miracle of metamorphosis had begun—and snow painted the peaks white.
    We debated what to do with our nascent adult eastern black swallowtail. She has no future inside or out. Yet she is the only butterfly our garden produced this year.
    If this heartbreaking hatch of a single caterpillar, whose maturity comes too late to seed future generations, is the gift of global climate change, I grieve for us all. Because what we are losing is not just a single species but the thread of connection with the everyday wild that secures our place in nature’s community.

    Susan J. Tweit is a plant ecologist by training and the author of twelve books, including her latest, a memoir titled Walking Nature Home: A Life’s Journey. She lives with her husband in a house heated and cooled by the sun in Salida, Colorado.

A Chambered Nautilus
    Ursula Freer
    Almost all mollusk shells are made of aragonite, a naturally occurring crystalline form of calcium carbonate. If we continue to follow the fossil-fuel-intensive scenario outlined by the Intergovernmental Panel on Climate Change, by 2060 the oceans will likely become so acidic that aragonite will start to dissolve.

    Ursula Freer is a painter and digital artist working in Sante Fe, New Mexico. Her work is primarily devoted to the beauty of the natural world.

    A chambered nautilus, Nautilus pompilius, phylum Mollusca, class Cephalopoda. Digital collage by Ursula Freer.

Salmon in Alaska
    Sue Mauger
    I HAVE WATCHED KING SALMON SWIM BY ME ON
their return to the Anchor River; over Memorial Day weekend the Chinook wend their way past wader-clad fishers at the river mouth as they head upstream to spawn. They swim along a channel that continually reworks itself, shifting gravel bars, moving downed cottonwoods, searching for new angles of repose after the two hundred-year floods of 2002. The sediment-rich waters flow out of the Caribou Hills; snow is still melting from the two-hundred-square-mile watershed, which is virtually undeveloped compared to the Lower Forty-eight.
    The returns of king salmon to the Anchor River have been strong, even though the forest has died. After the warm, dry summers of the 1990s, the bark beetles swarmed in dark clouds and ate their way across 1.4 million acres of the Kenai Peninsula. The dead gray trees that remain after the salvage logging and windstorms are a reminder of the forest that was.
    I first stepped into the