- Author: Kathy Keatley Garvey
Westward, ho!
The western migration of the Monarch butterflies (Danaus plexippus) to their overwintering sites along the California coast is underway.
Butterfly expert Art Shapiro, distinguished professor of evolution and ecology at the University of California, Davis, recorded four Monarchs at his Suisun monitoring site yesterday. He's been monitoring butterflies in Central California for some four decades.
This morning, a male Monarch fluttered into our yard to sip some nectar from a Mexican sunflower (Tithonia). (A distinguishing feature of the male Monarch: a small black spot on each of its two hindwings. See photo below.)
Monarchs head for sites along the coast, including Santa Cruz, Monterey, Natural Bridges and Pacific Grove, to overwinter, Shapiro noted.
"There used to be a small site in Fairfield, near the old Juvenile Hall on West Texas Street, in a row of Eucalyptus. It's been gone for decades. Some years they try to overwinter in Marin and Sonoma counties, but usually give up and shift south in December. In the past few years there has been a little winter breeding on the south coast. This was never recorded before."
The migration of the Monarchs to overwintering sites in central Mexico is well-publicized, but some monarchs head for the California coast. According to the monarchwatch.org website, monarchs east of the continental divide generally migrate to central Mexico from as far away as Ontario, Canada. "Monarchs west of the divide fly to the coast of California to spend the winter. They cluster together on tree limbs during the winter months in California by the thousands, and in central Mexico by the millions." (Download the PDF on the monarchwatch.org site.)
We're glad to see the huge national campaign to plant milkweed, the host plant of the Monarchs. The Xerces Society for Invertebrate Conservation has posted a wealth of information on its website for us to take action. The Monarch population has declined by more than 90 percent in under 20 years.
“Monarch butterflies are declining due to loss of habitat,” said Monarch Watch director Chip Taylor. “To assure a future for monarchs, conservation and restoration of milkweeds needs to become a national priority.”
It also helps to provide nectar resources for the Monarchs to help them along in their migration. In our yard, they like the Mexican sunflower (Tithonia), the butterfly bush (Buddleia davidii), and blue beard (Caryopteris × clandonensis). See list of Monarchs' favorite plants on the monarchwatch.org site.
Meanwhile, an occasional Monarch flutters into our family bee/butterfly garden to sip some nectar. Sometimes territorial native bees chase them away but the Monarchs return, determined to grab some flight fuel.
Westward, ho!
- Author: Kathy Keatley Garvey
The Xerces Society for Invertebrate Conservation issued news today that is both disturbing and hopeful.
Disturbing in that the monarch butterfly population (Danaus plexippus) has declined by more than 90 percent in under 20 years.
Hopeful in that the monarch may receive federal protection through the Endangered Species Act.
The Xerces Society, the Center for Biological Diversity, the Center for Food Safety, and monarch scientist Lincoln Brower, have filed a legal petition with the U.S. Fish and Wildlife Service to protect the monarch through the Endangered Species Act. The agency must respond within 30 days as to whether the petition warrants further review.
“Monarchs are in a deadly free fall and the threats they face are now so large in scale that Endangered Species Act protection is needed sooner rather than later, while there is still time to reverse the severe decline in the heart of their range,” related Lincoln Brower, preeminent monarch researcher and conservationist, who has been studying the species since 1954.
Tragicallly, the monarchs have lost more than 165 million acres of habitat, including nearly a third of their summer breeding grounds that contain their host plant, milkweed. The female monarchs lay their eggs on milkweed and this is the only food their larvae eat.
As Lynn Kimsey, director of the Bohart Museum of Entomology and professor of entomology at UC Davis, told us today: "Might be too little too late but they have to preserve/conserve milkweeds (Asclepias spp.) That's more important than the butterfly itself."
Xerces earlier sounded the alarm on the critical role that milkweeds play in the monarch's life cycle.
Senior scientist Tierra Curry of the Center for Biological Diversity, hammered home this point in the news release: “The 90 percent drop in the monarch's population is a loss so staggering that in human-population terms it would be like losing every living person in the United States except those in Florida and Ohio.”
And the loss of habitat is equal in size to the state of Texas.
The news release said that the butterfly's dramatic decline is "being driven by the widespread planting of genetically engineered crops in the Midwest, where most monarchs are born. The vast majority of genetically engineered crops are made to be resistant to Monsanto's Roundup herbicide, a uniquely potent killer of milkweed, the monarch caterpillar's only food. The dramatic surge in Roundup use with Roundup Ready crops has virtually wiped out milkweed plants in midwestern corn and soybean fields."
Science policy analyst Bill Freese of the Center for Food Safety was quoted as saying: "The widespread decline of monarchs is driven by the massive spraying of herbicides on genetically engineered crops, which has virtually eliminated monarch habitat in cropland that dominates the Midwest landscape. Doing what is needed to protect monarchs will also benefit pollinators and other valuable insects, and thus safeguard our food supply.”
Monarch butterflies are known for their spectacular multigenerational migration each year from Mexico to Canada and back, the news release said.
"The population has declined from a recorded high of approximately 1 billion butterflies in the mid-1990s to only 35 million butterflies last winter, the lowest number ever recorded," according to the release. "The overall population shows a steep and statistically significant decline of 90 percent over 20 years. In addition to herbicide use with genetically engineered crops, monarchs are also threatened by global climate change, drought and heat waves, other pesticides, urban sprawl, and logging on their Mexican wintering grounds. Scientists have predicted that the monarch's entire winter range in Mexico and large parts of its summer range in the states could become unsuitable due to changing temperatures and increased risk of drought, heat waves and severe storms."
Endangered species director Sarina Jepson of the Xerces Society worries--and rightfully so--that the monarch may become extinct, just like the passenger pigeon.
We are, too. We've seen only two--two--of these majestic butterflies fluttering in our family bee garden this year.
- Author: Kathy Keatley Garvey
Think of them as "the good guys" and "the good girls."
Insects such as lacewings, lady beetles and flower flies.
We're delighted to see that the Xerces Society for Invertebrate Conservation has just published a 250-page book on "Farming with Native Beneficial Insects."
The book advocates the use of beneficial insects to prey upon crop pests, thus "reducing or eliminating the use of pesticides," say co-authors Eric Lee-Mäder, Jennifer Hopwood, Mace Vaughan, Scott Hoffman Black, and Lora Morandin.
"This comprehensive guide describes how to recognize these insects and their habitat, and how to evaluate, design, and improve habitat for them," they write. They offer specific solutions, including native plant field borders, mass insectary plantings, hedgerows, cover crops, buffer strips, beetle banks, and brush piles.
The much-acclaimed book, available for purchase on the Xerces website, is drawing well deserved accolades, including this one from Claire Kremen, professor and co-director of the Berkeley Food Institute, University of California, Berkeley:
“If you are a grower or a backyard gardener, this is a ‘must have.' Readable and filled with gorgeous photos and handy charts, this book provides reams of information about how to get the upper hand on your pest issues with reduced or no pesticide use.”
Xerces officials say the release of Farming with Native Beneficial Insects coincides with its launch of a new nationwide workshop series on natural pest control: the Conservation Biological Control Short Course. The course, to begin in the West and Midwest, "provides farmers, crop consultants, and government farm agency staff with a comprehensive, hands-on training in the natural pest management strategies described in the book. A similar workshop model previously offered by Xerces trained tens of thousands of people in farm communities across the U.S. to conserve bees and restore pollinator habitat, and helped facilitate the restoration of more than 100,000 acres of wildflower habitat for bees."
Speaking of "the good guys" and "the good girls," be sure to read the UC Statewide Integrated Pest Management Project's website on beneficial insects and natural enemies. The natural enemies include assassin bugs, bigeyed bugs, brown lacewings, convergent lady beetles, damsel bugs, dustywings, syrphid flies and twicestabbed lady beetles.
What is Integrated Pest Management (IPM)? "Integrated pest management uses environmentally sound, yet effective, ways to keep pests from annoying you or damaging plants. IPM programs usually combine several pest control methods for long-term prevention and management of pest problems without harming you, your family, or the environment. Successful IPM begins with correct identification of the pest. Only then can you select the appropriate IPM methods and materials."
UC IPM points out:
- Many pests can be managed without the use of pesticides.
- Use pesticides only if nonchemical controls are ineffective and pests are reaching intolerable levels.
- Use pesticides in combination with the methods described above.
- Choose pesticides carefully. Use the least toxic, most effective material to protect human health and the environment.
- Examples of least toxic insecticides include:
- Soaps;
- Oils; and
- Microbials such as Bacillus thuringiensis (Bt) and spinosad.
The more we learn about pests and the natural enemies of pests, the oft-heard quote, "Keep your friends close and your enemies closer" rings quite true. The more we learn about our enemies, the less likely they will be able to harm us.
- Author: Kathy Keatley Garvey
Got milkweed?
If not, monarch butterflies are in a heap of trouble.
An interesting study just published in journal PLOS One by researchers at the University of Jamestown, North Dakota, and the University of Georgia, Athens, Georgia, revealed that the larvae of monarch butterflies that skip meals (host plant, milkweed) will become adults with a smaller wing size, as much as 2 percent smaller.
That's important because monarch butterflies (Danaus plexippus) are migratory animals that travel long distances, and without milkweed, Asclepias spp., their migration will be adversely affected.
In their research, “Does Skipping a Meal Matter to a Butterfly's Appearance? Effects of Larval Food Stress on Wing Morphology and Color in Monarch Butterflies,” Haley Johnson of the University of Jamestown and her colleagues also found that monarch larvae deprived of food became adults with a different wing coloration: paler wings.
This study nails home the point why we need to plant milkweed. As the Xerces Society for Invertebrate Conservation says on its website: “The loss of milkweed plants in the monarch's spring and summer breeding areas across the United States is believed to be a significant factor contributing to the reduced number of monarchs recorded in overwintering sites in California and Mexico. Agricultural intensification, development of rural lands, and the use of mowing and herbicides to control roadside vegetation have all reduced the abundance of milkweeds in the landscape.”
To address this seed shortage, the Xerces Society launched Project Milkweed to produce new sources of milkweed seed “where seed has not been reliably available: California, the Great Basin, Arizona, New Mexico, Texas, and Florida."
Bottom line, the Xerces Society is:
- raising public awareness about milkweeds' value to monarchs and native pollinators
- promoting the inclusion of milkweeds in habitat restoration efforts
- developing milkweed seed production guidelines, and
- building new markets for milkweed seed.
The Xerces website also offers sources of native milkweed seed in your state.
Meanwhile, the butterflies that overwintered in Mexico are on the move and in Texas. For more information on butterfly migration, see Monarch Butterfly, Journey North.
- Author: Kathy Keatley Garvey
The world's "100 Most Endangered Species" are back in the news again, and well they should be.
Back in 2012, The International Union for Conservation of Nature (IUCN) and the Zoological Society of London released a list of the 100 Most Threatened Species when the IUCN World Conservation Congress met in South Korea.
It's good to see the list is still making the rounds. A slide show posted this week by Huffington Post should keep it in the spotlight. Last year Live Science listed them.
That means more attention to Franklin's bumble bee (Bombus franklinii), a critically imperiled bumble bee that UC Davis native pollinator specialist Robbin Thorp has monitored since 1998.
Thorp, emeritus professor of entomology, says the distinctively marked bumble bee has the most restricted range of any bumble bee in the world. Its habitat is--or was--a small area of southern Oregon (Douglas, Jackson and Josephine counties) and northern California (Siskiyou and Trinity counties).
Franklin’s bumble bee frequents California poppies, lupines, vetch, wild roses, blackberries, clover, sweet peas, horsemint and mountain penny royal during its flight season, from mid-May through September. It collects pollen primarily from lupines and poppies and gathers nectar mainly from mints.
Thorp and the Xerces Society for Invertebrate Conservation are the forces behind the Franklin's bumble bee campaign to find it and protect it. See the Xerces website for more information about the bee.
Thorp sighted 94 in 1998; 20 in 1999; 9 in 2000 and only 1 in 2001. Sightings increased slightly to 20 in 2002, but dropped to 3 in 2003. Thorp saw none in 2004 and 2005; one in 2006; and none since. Now scores of people from all walks of life are looking for it, but no one has found it.
Franklin's bumble bee is one of several insects on the worldwide list. The other species include several butterflies, Actinote zikani, Parides burchellanus and Pomarea whitneyi; the Seychelles Earwig (Antisolabis seychellensis); Beydaglari Bush-cricket (Psorodonotus ebneri); and a damsel fly (Risiocnemis seidenschwarzi).
Or Franklin's bumble bee.