Plight of the pollinators: From monarchs to honey bees, the helpful insects are in decline

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MONARCH BUTTERFLIES IN DECLINE

Monarch butterflies have experienced losses of approximately 90 percent of their populations in recent years. Tina Shaw/U.S. Fish and Wildlife Service

Gardening takes faith.

It’s a faith that Ric Plese, local horticulturist and owner of Cliffrose Garden Center and Gifts in Cortez, has been cultivating in his customers for 16 years and counting. Faith that it will rain, and that it won’t snow. Faith that the sun will shine, but not too hot, and that the growing season will last long enough for plants to bear fruit. A belief that seeds will germinate, that the soil is proper, and that pollinators will show up.

But lately pollinators have been showing up to farms and gardens across the United States in fewer and fewer numbers. The decline is so pronounced that the Obama administration recently issued what was dubbed an “all hands on deck” call to ensuring future pollinator health. The administration plans to help armies of bees, butterflies, moths, bats, birds, beetles and any number of other crawling or winged creatures seeking fresh blooms and foliage through direct action, research and partnerships. The National Strategy to Promote the Health of Honey Bees and Other Pollinators, created by the Pollinator Health Task Force, a group appointed by President Obama last June, was released by the administration on May 19.

The lengthy document calls for dedicating the highest levels of the American government to reversing devastating domestic honey-bee colony losses, increasing monarch populations before the butterfly goes extinct across America, and restoring or enhancing 7 million acres of land over the next five years to benefit pollinators.

Here in Cortez, Plese hasn’t seen the recent declines in pollinators affecting his plants. “I know people who have bee colonies and that they have their declines,” Plese said in a recent phone conversation. “But on my nursery stock, it’s insane all the things buzzing around – when I see what’s on the flowers.” He noted that pesticides are not used at Cliffrose, and speculated that maybe his greenhouses are a sanctuary for local pollinators.

“Society needs to change,” Plese said. “One little patch in Montezuma County isn’t going to help the whole species.” He points to corporate agriculture’s vast monoculture fields of corn and soybean, liberally doused with pesticides, as the real issue. But he also believes that whatever homeowners can do to help will make a difference.

Now may be the time to make a difference for monarch butterflies. The large, beloved insects with orange, black and white wings found throughout North America have experienced a sustained population decrease of approximately 90 percent in recent years, according to the U.S. Fish and Wildlife Service.

The decline is so steep that the service is in the middle of a one-year review that will determine whether the monarch, and its critical habitat, will receive protection under the Endangered Species Act.

The monarch’s quirky penchant for travel sets it apart from other butterflies – and puts it at risk. According to the U.S. Forest Service, the monarch is the only butterfly known to make a birdlike two-way migration. A single generation of monarchs travels across the eastern United States, flying up to 3,000 miles and coming from as far north as Eastern Canada. They arrive en masse in the oyamel fir forests of the Sierra Madre Mountains in Michoacan, Mexico, northwest of Mexico City, in late October and stay for the winter. Their numbers are so great that their population is not counted in butterflies, but in the number of acres that they literally blanket, roosting together in trees for warmth.

This same generation of butterflies gets the traveling itch around February. After mating in Mexico, they head back north to lay their eggs on milkweed plants, the sole source of food for their larvae — very hungry, yellow-black-and-white- striped caterpillars.

Other butterfly species can survive a winter in the United States’ cold northern climates, either as caterpillars, cocooned chrysalises, or even as butterflies. Monarchs cannot – they must migrate or die – and their little-understood though much-studied migratory feat only adds to their appeal.

To add another complexity to their particular ways, several generations of monarchs complete the journey north in the spring. These successive generations live a mere two to five weeks, compared to the winter set’s longevity of nine months. Each generation is compelled to find flower nectar for food and stands of milkweed for egg-laying and caterpillar nurseries, or the links in the great monarch migration are broken.

In the western United States, a similar, but shorter migration takes place between the Rocky Mountains and the sunny environs of Southern California. The Four Corners region bisects the eastern and western migration routes. The western monarch population has experienced the smallest decline, although the decrease in local monarch populations is still pronounced.

“I have not seen a living monarch in at least 10 years,” said Deborah Kendall, a doctorate professor of entomology at Fort Lewis College. “In the past, monarchs would migrate through our local habitats from overwintering habitats in Mexico and Central America. They would follow the progressive milkweed flowering times as they migrated northward.”

Kendall said monarchs are extremely rare due to both habitat destruction and the spraying of herbicides on their host plant, the milkweed. Enormous populations have been destroyed in their overwintering sites in Mexico and additional habitat has been lost because of insufficient regulation of monarch habitat and pesticide application, especially on crops.

The president’s pollinator strategy plan agrees, citing the primary stressors as the loss of milkweed breeding habitat in corn and soybean fields, the loss of breeding habitat due to development, illegal logging and deforestation at overwintering sites, and extreme weather conditions that drop the temperature or humidity below what monarchs can endure.

In addition, diseases, parasites, and predators, such as assassin bugs that attack caterpillars like vampires, piercing them with their sharp beaks and sucking out their body liquids, all contribute to population declines. Even a few species of birds can tolerate the high levels of poisonous cardenolides found in the butterflies and caterpillars, a toxin in the milkweed that caterpillars eat. These birds can quickly reduce monarch populations.

Farmers, ranchers and homeowners also contribute to population decline when they use insecticides.

Although the harm done to pollinators by pesticides in general, and neonicotinoids specifically, is addressed in the plan put forth by the Obama administration, the plan calls for further study instead of direct action. Neonicotiniod pesticides protect plants against insects that would like to eat them, when the poison is applied to the seed, roots, or other part of the plant, and the plant spreads it to all areas, including leaves, nectar and pollen. Neonicotinoids are more toxic to insects than to mammals, and were thought to be a safe way to prevent pests. However, published studies have shown that neonicotinoids can be a deadly neurotoxin to bees and that bees are sensitive to prolonged exposure.

The president’s strategy cites the critical role pesticides play in no-till agricultural, invasive-species control, and in suppressing insects that transmit human diseases or kill crops. The document also claims “it is the misuse and overuse of these pesticides that leads to adverse ecological and human health consequences.”

But not everyone shares this view. In response to the President’s plan, Lisa Archer, Food and Technology Program Director at Friends of the Earth, said in a statement, “Four million Americans have called on the Obama administration to listen to the clear science demanding that immediate action be taken to suspend systemic bee-killing pesticides, including seed treatments.” Lending a hand to monarchs, and other butterflies that are more commonly found in our region such as the tiger swallowtail, mourning cloak, painted lady, juniper hairstreak, sulphur and cabbage white, can be as easy as growing milkweed and forgoing pesticides and herbicides. “Flat flowers attract butterflies,” Plese said.

Plese sells three varieties of native milkweed in pots and four varieties of seeds for planting at his greenhouse. Four Seasons Greenhouse in Dolores has already sold all of their butterfly milkweed for the summer.

Several varieties of the plant will grow locally and will sustain monarchs and many other pollinators. Plese said that the perennials take full sun and can be planted in versatile soil, but can be killed by overwatering. He noted that milkweeds have other benefits: they are deer resistant, have fragrant delicate blooms that make cut flowers for decorative use, and grow up to 3 feet tall, adding variety to a flower garden.

To attract additional local pollinators, such as domestic honey bees and their wild and native counterparts, such as bumble bees, leaf-cutter bees, sweat bees, and several fly species that resemble bees, such as syrphid flies and bee flies, Plese recommends leaving dandelions alone, and planting nectar-rich flowers such as Russian sage or blue spirea. “Bees just love it! They [the blue spirea] are just loaded with bees. The bees are so inebriated with the nectar that they aren’t a nuisance.”

Although it is already June, Plese said it’s not too late to plant. “People think you can only plant in the spring. With containerized plants you can plant all year long.”

To learn more about monarch butterflies and other pollinators, visit Xerces Society for Invertebrate Conservation at www.xerces.org.

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