Illegal Logging “Stopped,” but Climate Change, Aerial Insecticides Spell Challenges for Monarch Butterflies

Good news from the Monarch butterfly roosting sites in the mountains of Michoacan this week: for the first time since the creation of the Monarch Butterfly Biosphere Preserve in 2000, officials declared that illegal logging there has practically been eliminated.

Logging

Illegal logging in Mexico has practically been eliminated, says the World Wildlife Fund, Mexico

Mexican government officials and the World Wildlife Fund, Mexico, made the announcement after a review of aerial photographs of the Oyamel forests in Michoacan province this week revealed no detectable loss of forest to logging.  Approximately 50 acres fell victim to drought, erosion and disease.

“The battle is not yet won,” Omar Vidal of the environmental group WWF Mexico, told the Associated Press in a widely circulated report.

Unfortunately the good news in Mexico was tempered with the harsh reality that 2012 will be tough for the Monarch butterfly migration this fall.  A year “like no other,” according to Dr. Chip Taylor, founder of Monarch Watch–and a year that includes climate change, drought, wildfires, and now massive aerial insecticides in the strategic North Texas migration flyway.

Monarch migration map

Monarchs must pass through Texas coming and going to Mexico.

The year started with a wet spring that arrived strong and early, creating a timing snafu here in the “Texas funnel.” The Lone Star State is always the first stop on the multi-generation Monarch migration spring tour.  A sound launch here in April, based on mild temperatures and fresh, ample milkweed host plant, sets up a successful first generation of Monarch butterflies to lay eggs, hatch caterpillars and chrysalises, and carry the torch northward.

But that didn’t happen this year.  The Texas spring came on hot, early, and accompanied by strong winds.  When Monarchs arrived in March, a lot of wild milkweed wasn’t even out of the ground yet.    The wet, mild winter provoked a bountiful wildflower showing, creating serious competition from more aggressive species.

Then we had a slew of 80- and 90-degree days that sped up growth of both the caterpillars and plants.  Readers of this blog contacted us with tales of a serious milkweed shortage.  “Plants grew rapidly this spring with many species blooming 10-30 days earlier than normal,” wrote Taylor in his annual Monarch Population Status blogpost, published July 30.  ”Plants that typically flower in the fall began blooming in June and reports continue of water stressed plants blooming early.”

Resident Monarch butterfly at the San Antonio River Milkweed Patch

Milkweed shortages dogged Monarch butterflies this year.

That’s a problem because Monarch caterpillars prefer young, healthy plants rather than those that are over-the-hill and “senescing,“ as scientists call it.  Studies of caterpillars reared on older, mature milkweed suggest less healthy butterflies, and problems like the OE virus and tachinid flies are more common.

Summer brought extreme heat and no rain, with the historic drought suffered in Texas last year now expanding to the Midwest–not good for butterflies and devastating for host and nectar plants.  Successive generations of Monarchs seem to having a tough time syncing their schedules with the new climate calendar and plants seem confused, too.

It will be an interesting migration.   We generally start to see the vanguard of migrating Monarchs in late August here in Texas.  By Labor Day, a dribble of early arrivals grace our goldenrod at the ranch.  On the way, they will have seen a torched landscape from wildfires in the Midwest and Oklahoma, and now, massive aerial insecticide sprays in Dallas, a response to an outbreak of West Nile virus there.

The aerial spraying of insecticides like Duet, the chemical dispersed last night over 106,00 acres of Dallas county, has not taken place since 1966.  The Environmental Protection Agency and Centers for Disease Control and Prevention have said that Duet, comprised of synthetic pyrethenoids, are safe and pose no health risk to humans or pets.  Descriptions of the chemical provided by Clarke Corporation say the chemical is even safe for bees.

Scientists and citizens expressed reservations about aerial spraying.  The Dallas-area town of Lancaster even voted to not participate in the program.

Dr. John Abbott, Curator of the Entomology Collection at the University of Texas at Austin, questioned the effectiveness of such a measure.  ”All this will do is knock out the adults that are flying, but it doesn’t do anything about the eggs and larvae,” he said.

“Aerial spraying will kill some, but not all adult mosquitoes, but it won’t solve the problem since the spraying will not impact the breeding sites,” said Dr. Taylor via email.   “Why aren’t they attacking the breeding sites?”

Dr. Mike Merchant, Professor and Extension Urban Entomologist at the Texas AgriLife Extension Service in Dallas, dismissed concerns of Duet effecting the Monarch migration.  ”I wouldn’t anticipate that Duet would have much impact on Monarch migrations or survival, ” he said via email.  ”The insecticide lasts for just a few hours before degradation or evaporation.”   Merchant added that since spraying is done at night, butterflies would be less likely to encounter it and that studies suggest these insecticides are less toxic to larger insects.

“That said, we are taking a wait and see approach,” he wrote.

And that’s what we will do, as we await the first arrivals of this year’s Monarch migration.

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Wildflower Bonanza-to-be on the San Antonio Mission Reach, Thanks to Above-average Rains

Bluebonnets, coreoposis, red and blue sage–who knew it was February in San Antonio, Texas?   Recent Texas rains have drenched our drought-parched landscape, but Nature seems bent on making it up to us.

A recent walk on San Antonio’s Mission Reach, the nine-mile linear park that extends from the south part of downtown San Antonio all the easy to Mission Espada, revealed bounties of budding wildflowers, awaiting slightly warmer temperatures and doses of daily sunshine to put out full blooms.  After the 2011 historic drought, it’s heartening.   The butterflies will follow shortly, as will the birds who find their caterpillar life stage a favorite treat.   Not far behind are other returning critters–raccoons, opossums, nutria, even foxes and coyotes eventually.

For a quick preview of what’s coming later this spring, see the slideshow above.   For insights on the complex collaboration of planners, scientists, engineers and specialist contractors tapped to set the stage for these blooms, see my story at The Rivard Report.

Occupy Michoacan: Monarch Butterflies Move West Because of Deforestation and Climate Change

Monarch butterflies seem to have taken a cue from our Wall Street protesters and moved to more friendly environs for the winter.  The migrating insects, numbering in the millions, have moved slightly west in their roosting sanctuaries, from Mexico state to Michoacan, says a report in El Diario Michoacan.

Monarch butterflies in Michoacan

Monarch butterflies in Michoacan

“It appears the butterfly now prefers the forests of Michoacan to those in Mexcio,” stated a dispatch on the website of the daily publication based in Uruapan, the municipal seat for Michoacan province.

The article quoted Oscar Contreras Contreras of the Monarch Butterfly Conservation Foundation (Funacomm) who said climate change and human activity such as illegal logging have been causing changes in the butterflies arrival and departures dates and population size for the past five years.

El Diario quoted another source who said that in the La Mesa sanctuary, in the town of  San José del Rincón, the butterflies only stayed for two months “because now the conditions for their hibernation and protection no longer exist.”

The butterflies typically occupy 12 sanctuaries that straddle the mountains of the Southern Sierra Madre and Transvolcanic Belt in the Mexican states of Michoacan and Mexico.  Their whereabouts change from year-to-year, and they move within and between the sanctuaries before taking flight in February and March to begin their migration north.

But this year seems different.

Monarch watchers are predicting a dreadful count, as a result of drought and wildfires in Texas, general habitat loss throughout the country and tough conditions in Mexico–environmentally and economically.  The budding ecotourism industry built around the migration has been stopped in its tracks by narco violence, which has caused many tour operators to cease organizing Monarch butterfly watching tours for fears of safety.  It would be no surprise that local Michoacanos might return to illegal logging as a way to feed their families and warm their homes.

We await official reports on this year’s population status, usually made available in February or March.   Like the Occupy Wall Streeters here in the U.S., there’s no question the butterflies will return this spring–but in what numbers?

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