A new study finds that monarch wings are getting larger, possibly because climate change has forced the butterflies to travel longer distances as breeding grounds shift farther north.
It’s not too late to save them, but it’s a question of whether we make the effort, scientists say.
6 Minute Read
PUBLISHED December 21, 2018
The epic 3,000-mile monarch butterfly migration may become a thing of the past. Each fall, monarchs travel from their summer homes in the northern U.S. and Canada to winter habitats in California and Mexico. But the 2018 Western Monarch Thanksgiving Count found that the number of west-coast monarchs spending the winter in California had plunged to only 20,456 butterflies—a drop of 86 percent since last year. And the number of eastern monarchs overwintering in Mexico this year has dropped 15 percent since last year, for a total decline of more than 80 percent over the past 20 years, according to the National Wildlife Federation.
“A lot of environmental threats can pile up on top of each other,” says University of Wisconsin entomologist and director of the UW-Arboretum Karen Oberhauser. And the consequences can be hard to predict.
Although monarchs teeter on the edge of an extinction tipping point—in which their numbers drop too low for the species to recover—scientists like Obserhauser say all is not yet lost. Creating new monarch habitat by planting native milkweed species may provide crucial fuel and rest stops for the traveling butterflies, as will taking more action to address climate change.
WHERE’S THE MILKWEED?
A 2004 email from a Midwestern farmer first alerted Kansas University entomologist Chip Taylor to the pending monarch apocalypse. The creation of herbicide-resistant corn and soybeans meant that farmers could eradicate weeds and other understory plants, including milkweed, that competed with their crops.
The invisible hand of fear and dread gripped Taylor’s gut. He had spent years studying monarchs and knew they depended on the milkweed studding their migratory corridor across the Midwest. The advent of these new crop varieties meant the death of milkweed.
Data over the next few years only confirmed Taylor’s worst fears: monarch numbers began to plummet. “In a very short period of time, monarchs took a tremendous hit, with tremendous consequences,” Taylor says.
In addition to the loss of milkweed across farms, drought also harms milkweed quality. A 2013 drought in Texas decimated milkweed there, which contributed to low monarch numbers that year.Nectar-rich flowers are important for monarchs’ continued survival. And milkweed, the only plant monarch caterpillars eat, is especially important.The loss of milkweed has clued in an increasingly concerned public that the beautiful butterflies they love might go the way of the passenger pigeon and the woolly mammoth. Awareness of vanishing milkweed bled over into fears of how monarchs would fare as the climate continued to change. A series of papers in the last few years shows that these worries were not misplaced.
Rising carbon dioxide levels from the burning of fossil fuels sit at the heart of climate change, and this increase of carbon can alter how plants like milkweed build certain molecules, explains ecologist Leslie Decker, a postdoctoral researcher at Stanford University. Milkweed produces toxic steroids called cardenolides. The monarchs have evolved in a way that allows them to tolerate low levels of this poison, storing it in their bodies as a bitter-tasting deterrent to predators.
Models predict an 11 to 57 percent chance that monarch numbers would drop so much in the next 20 years that the species wouldn’t be able to recover.
Cardenolides also help the butterflies by impeding the growth of a monarch parasite with the tongue-twisting name Ophryocystis elektroscirrha. “I had to practice pronouncing this when I was in grad school,” Decker laughs.
The single-celled parasite can infect newly hatched caterpillars by drilling holes in their gut to replicate. If the caterpillars survive, the resulting butterflies have misshapen wings and lowered endurance. Cardenolides help the monarchs tolerate the parasite so that it doesn’t harm them.
But when Decker grew milkweed in a greenhouse with carbon dioxide levels of 760 parts per million (ppm)—what climate scientists project will happen in 150 to 200 years as the current level of 410 ppm continues to rise—she found that the plants produced a different mix of cardenolides, one that was less effective against monarch parasites. She published her findings in July 2018 in Ecology Letters.
“We don’t know how we’re changing the green pharmacy around us,” Decker says.
Read the full story here
HT/RobD
So what did they do during the Medieval Warm Period? Utter utter unsubstantiated speculation.Since when was speculation part of the scientific method? Assertion without statistically significant empirical data to support is is just that. Alarmist Rubbish!
The MWP is evidence that the current warmth is not unprecedented. That’s not really the problem here.
This is a continuation of the ‘enhanced CO2 makes plants less nutritious’ meme. The problem with that is that greenhouse growers use enhanced CO2 with food crops with no noticeable loss in nutrition content. link
This is the age of “Millennial Science”
o Feelings, not a well articulated, falsifiable theory is what counts
o There are safe spaces from having to face reality
o We’re spending other people’s money, so ethics be damned
o Scientific opinions of people who wouldn’t know a differential equation if it bit them in the ass (especially psychologists,) are every bit as valid as dudes with physics PhDs (especially if the PhDs are skeptics)
o Facts do matter, as long as they are ours
o Of course we don’t want to beat anybody up or throw them in jail simply for their opinion … ooops … scratch that
o The cumulative IQ of the 97% of us that believe this is the way to proceed is less than 97
Maybe it’s postmodern education in general. Camille Paglia notes the death of overview courses in the arts because there is nobody with sufficient breadth of knowledge to teach them. link
Time after time, we see papers published that contradict well known and widely confirmed facts. In this case, as I observe above, we have a ton of papers asserting that extra CO2 will reduce the nutritional content of food crops. That is in the face of the fact that greenhouse growers routinely enhance CO2 to increase yields and there is no evidence that their crops are less nutritious.
There is the old joke about PhDs who know more and more about less and less until they know everything about nothing. link A scholar who doesn’t know how her subject fits in the context of the greater world isn’t much of a scholar.
Well, the answer is simple. Plant Milkweed. The plants are extremely resilient to drought and work very well in front yards everywhere in Texas at least. The only problem is that if you plant milkweed in your garden, Monarch caterpillars will arrive everywhere and eat almost the entire plant.
The wife and I have several milkweed plants in our English garden. The first year we hatched about five monarchs. Since then, none. Not sure why.
Monarchs were plentiful here in northern Michigan
Those must be very hardy.
The monarch is COMPLETELY DEPENDENT upon the milkweed plant for its entire life cycle. The milkweed grows back pretty quickly. I have a few plants and the larvae ate them all up, so only the stalks were left, then they disappeared. (I hope they weren’t eaten!) but the milkweed grew right back, within weeks! (North Florida)
You do have to thin the eggs. Remove all but one visible egg (it’s my thought you’ll never remove all of them, I say leave one just in case you do find them all but you’ll probably have as many as 6 hatch) so they don’t denude the plant and then starve before they reach maturity. I can confirm from experience that only 3-4 caterpillars/per plant are too many.
Agreed! More milkweed to offset losses from herbicides is the most likely answer.
How about Glyphosate-resistant milkweed?
Would it give the butterflies cancer?
Loss of habitat/ milkweed in N. Am. is only a small part of the problem. The loss of Mexican forests that support the Monarchs on the southern leg of their life-cycle to make room for the growing of avacados is the biggest problem.
What! There’s a variable that isn’t in the models which completely invalidates the CAGW science. Blasphemy! Fund 50 times more articles so he’s silenced and invalidated. Whew! Almost let the truth out again. We don’t want that happening.
Ah! right.
Lets just introduce milkweed like we encouraged the growth of palm oil plants, to save a butterfly.
A milkweed that’s been ‘tested’ in a greenhouse (read test tube) at 760 ppm with, of course, no external influences on the plant.
What could possibly go wrong?
In these areas, milkweed is a native plant. It’s not an introduced species.
And there are several kinds of milkweed too.
Common Milkweed, Asclepias syriaca, is native to the lower 48. It’s decreasing in numbers as farms use roundup-ready seeds, which enable total eradication of weeds via arial spraying.
Oddly, the Maryland DNR has taken to planting milkweed in median strips. Not sure the survival rate of Monarchs that cross the median to lay eggs.
Here in west MD, there is plenty of milkweed. But there is limited farmland & alot of woodland edges, so I realize the situation might be quite different in areas w/little woodland edges (which are away from the farmers’ herbicides) where the milkweed can proliferate. One thing I do notice tho, is that over time grasses (native and introduced) can choke out not only milkweed but even the mainstay of open, ungrazed fields –goldenrod and asters.
There is a project, already funded and operated on. It involves planting milkweed in the “median” between the two side (lanes) of I-35, from MINNESOTA to Louisiana.
This helps compensate for the milkweed that has been removed from farmer’s fields because of “universal” application of Roundup, on genetically engineered “Roundup” resistant plants. The YIELDS are much better with this practice, but all extraneous plants are removed. (Milkweed was not considered a big problem in Corn fields, for example. So farmers did not try to get rid of it.)
I-35 does not go to Louisiana. It runs MN, IA, MO, KS, OK, TX
We quit growing corn on the farm from 1988 to 2012 because we needed forage for the dairy cattle and corn was usually cheaper to buy than produce. Prior to 1988 milkweed did not grow in the cornfields, atrazine, a few other herbicides, and cultivation kept the fields pretty clean. Milkweed grew in the fence rows which we still have on the farm but most of the neighbors have removed theirs.
The other thing that changed was the influx of urbanites to development communites that took farmland (and fencrows) out in favor of green desert lawns. And in winter those people complained like crazy when snowy roads kept them from rushing home. So the townships started mowing the ditches more often and in fall will mow almost the entire right of way to reduce snow drift. Time to quit blaming farmers for problems that have a lot of causes.
gail
Thank you for your practical insight.
Salute gail,
Lots more to loss of the milkweed than Roundup [ the new poster child for evil human use of chemicals to increase food produciton for humans, the filthy vermin].
Secondly, we here in the Panhandle of Florida have a great migration of the critters, and not overgrown with milkweed, so I doubt the things only chew on milkweed, though they highly prefer it as another poster in north Florida has witnessed.
Lsstly, I likes this one
Apparently, the wintering grounds will stay where thay are presently and become living hell, exacerbating the poor scenario for the monarchs. The horror. But wait!!! If the normal flying range of the butterfly is like a rope of “x” length…….? And “gorebull warming” is truly “global”. And we pull the rope to the 30-year basis for anomalies? Wouldn’t the other end of the rope move northward or southward [for SudAmerica and Oz]’
Gums ponders….
Gums, you make good points, but know that the eggs of Monarchs are only laid on milkweed and the caterpillars only eat milkweed. Adults consume nectar like other butterflies.
gail nails the main issue!
From USA’s Fish and Wildlife department:
1) Small eco units have far more variables involved than just CO₂! Alleged researchers playing with doll gardens are fantasizing.
2) Farmers have never tolerated milkweed growing with their crops!! It is bad stuff to feed animals!
3) Farmers have always allowed fence rows, fallow ground, swampy grounds, etc to grow and provide shelter and food for wildlife
Urbanites and suburbanites are narrow minded regarding plants that harbor wildlife. Many thoroughly detest animals but chipmunks, a few rabbits and a few common birds. After they decimate the insect populations, they’ve knocked off or discouraged birds dependent upon those insects; e.g. bluebirds.
4) Anyone can plant milkweeds
5) Both milkweeds and monarch butterflies have coexisted for a very long time. Childish assumptions and false alarms are not scientific nor do they assist anyone or anything.
From “The Daily Garden“:
Those poor monarchs endure the carnage of crossing the freeway to get to the milkweed in the median…it’s almost like they want to kill them in car grills 🤔
Max H: “… planting milkweed in the “median” between the two side (lanes) of I-35…”
I can just see Monarch butterflies plastered all over the grills and windshields of cars and semi’s.
It involves planting milkweed in the “median” between the two side (lanes) of I-35,…
…great idea, sorta like baiting deer
At least they don’t plant the Moose’s favorite food in the median…
Information from those who actually show they care:
https://www.americanmeadows.com/perennials/milkweed/how-to-grow-milkweed
We live in Colorado Springs — we usually see few Monarchs during the fall migration. This fall, we had a glut of them. Don’t know if they changed their migration route, or what. We usually see a lot of Painted Lady butterflies instead.
A lot of wind farms in Texas. Can’t see a butterfly having much of a chance against those whirly things.
Monarks tend to fly low. well below the lowest tip of a wind turbine. So the wind turbines probably have minimal affect on the population. But that behavior makes them vulnerable to cars.
In the 90’s I was driving south on interstate 5 in California and my car kill a lot. As well as everyone else driving on the road that day.
During migration they are known to fly quite high. For example:
https://journeynorth.org/tm/monarch/HeightFallFlight.html
Turbulence from a passing blade could suck them up higher.
Approved.
and my car kill a lot. As well as everyone else driving on the road that day.
≠==========
Your car killed everyone…. that is where the problem is.
…minimal effect…
“Models predict…” is a red flag. Of course these people do not want to give up any luxuries to save anything, but talking it up is important to them.
So loss of milkweed feed is the primary threat to Monarchs, but of course climate change has zilch to do with modern farming practices that reduce milkweed density. But somehow, climate change is suddenly the topic of conversation.
Of course, exposing Monarchs who are adapted to 400 ppm CO2 to a sudden increase nearly doubling that cause a biochemical response. So? If doubling CO2 over the next 150 years is a real outcome, which of course cannot be predicted, there are hundreds of future generations of Monarchs will are most likely to gradually adapt to the gradual increase in CO2 and thereby produce quite different results than this.
Oh, and by the way, changes trace gas concentrations in the atmosphere is NOT “climate chang”e.
Duane
It was the milkweed they exposed to elevated CO2, not the butterflies.
No – if you read the article, the reduction in milkweed is solely due to modern farming practices such as widespread herbicide usage. The milkweed is not affected by CO2 at all, other than the fact that all plants that use photosynthesis to produce food require and thrive on CO2 which is why greenhouses typically pump more CO2 in to promote plant growth.
The study was clearly pointing to exposing monarchs to a near doubling of CO2 and measuring the biochemical changes in the butterflies.
Learn to read before commenting.
I know that spouting nonsense is your forte’, but did you really have to get so good at it?
Sheesh, could you try again, this time with the intention of making sense?
If your comment is aimed at Duane, then I’m not sure what your point was. With the exception of the doubling of CO2 being tested on the milkweed, not the butterflies, everything he said was correct. And even with the CO2 he was essentially correct. Hell, the experiment has to assume that NEITHER the milkweed or the monarchs can adapt to the raising co2 level over hundreds of generation. It also assumes that somehow in the next century we don’t come up with a better power generation source then burning Fossil Fuels. That seems unlikely to me.
~¿~
He’s a kneejerk idiot. He is POd at me because I am not a kneejerk Trump sycophant like he and quite a few other commenters and writers are at WUWT.
WUWT needs to stick to the science, and leave the political propaganda to the right wing media. The more that WUWT focuses on kissing Trump’s butt, the more credibility it loses in defeating climate alarmism. Remember that over 60% of Americans by virtually all polls think Trump is a moron and a loser. Trying to tie him into scientific skepticism of CAGW is the best way to lose the argument.
You’re a kneejerk idiot. Buzz off. My comment whizzed about a thousand feet above your ignorant head.
Want to know what is really going to decimate wildlife habitats in North America? The millions of new homes we’re going to have to build to accommodate the millions-to-billions of new residents arriving as a result of our de facto open borders policy.
Breeding grounds shifting to the north??
Is Point Pelee on the move? Someone ought to warn the Canadians!
Wikipedia: Monarch butterfly
Monarch butterfly research history in Canada dates back to about 1937.
Article includes photos of Monarch butterfly migration marking to collect information. Also includes many references on Monarchs.
https://en.wikipedia.org/Monarch_butterfly_migration
Aarghbh! Nothing to do with climate change. Mostly to do with the susceptibility of milkweed to herbicide, and conversion of wild meadows to mowed hay land by farmers.
Many thanks for the hat tip.
This article caught my attention as my brother in law lives on the coast just south of Santa Barbara where his dozen or so cliff side trees have in the past easily held 20,000 Monarchs each. The butterfly count was probably low because they were either a bit early or a bit late. These aren’t Capistrano Swallows. Of course this year’s extensive fires might have had something to do with lower and/or disrupted counts.
Rob_Dawg
Smells all a bit Polar Bear fishy to me.
A bit like the Bee’s that were all going to die and put paid to humanity. But didn’t.
Sniff test methinks.
There were exactly “20,456 butterflies” this year in California. There was an 86% drop from the year before (30,084).
Throwing out estimates like “20,000” just shows that your empirical evidence is not be trusted. If you want to establish credence with the California butterfly counting society you need to be (act) more precise; you should say “20,019” or “19,974” to let everyone know that you know what you are talking about. 🙂
There is probably a law in California requiring them to register. That is how they can be so precise.
California knows the number of Monarch butterflies in the state down to the single digits, but can only estimate the number of illegal aliens to within an order of magnitude.
~¿~
We have a 10 day cooling off period on metamorphosis, so all butterflies must first register with the state.
We currently grow increasing yields of staple crops on a reducing land area due to the same mentioned improvements in crop varieties and many other enhancements in agricultural efficiency. This is further aided by rising CO2 and a very slight rise in average temperatures. The result is less hunger and more land left in a natural state where milkweed and other wild plants can flourish. Those wild plants can also benefit from the increasing CO2 and warmth as evidenced by the global greening measure by satellites. In fact the biosphere that supports monarchs is being enriched by the gas that radical environmentalists and hoodwinked policy makers have labeled a pollutant. Perhaps these facts deserve equal coverage to the more alarmist assumptions and guesses presented above.
Part of the problem has been the increased acres being used to grow corn for fuel.
Part of the problem has been the increased acres being UNNECESSARILY used to grow corn for fuel, WHEN THERE’S PERFECTLY GOOD OIL FOR THAT.
There, fixed it for ya (yes, I know I’m “preaching to the choir”).
nothing crossing the boarder is required to register in California same can be said for Organics
Perhaps that was in response to Phillip, above?
Yes. Complete waste of land, no environmental benefits and makes food more expensive for those who can least afford it. Every day politicians fail to fix this is a travesty.
> more land left in a natural state where milkweed and other wild plants can flourish.
Not sure where you hail from but in agricultural Southern California the trend has been quite the opposite. Interstitial sites have been systematically repurposed for industrial agriculture.
Not here in Indiana. I don’t think I’ve ever seen in my lifetime even a single acre ‘farmed’ that wasn’t already part of a field. WHAT went into each field might change based on market expectations and crop rotation plans, but no new fields were ever created out of fallow ground.
What has happened is just the opposite. New subdivisions keep expanding the suburbs outward, and in the country new homesteads keep cutting out an acre or five from formerly productive fields. And all that land looks like it’s going to be out of the farming circle for good.
~¿~
I’ll try not to get too long winded with my post.
I have lived all of my 56 years in the same central Texas city (Temple, TX). It has grown from around 35,000 people when I was a teenager to around 75,000 people now. Yet it still takes only minutes to travel to rural areas outside the city limits.
Here are the land use changes I have noticed over these years. Much of the land near the city that used to be farms, ranches and fields are now covered with subdivisions. So all of the native plants have disappeared to be replaced with manicured green lawns.
Now expand on that process. Larger metropolitan areas, Dallas/Ft Worth, Houston, Austin, San Antonio cover large areas of land where native plants may be far and few between.
A couple of years ago I conversed via email with a professor that studies Monarchs. I had some questions regarding current building practices, more houses on smaller lots, more privacy fences, etc and whether this impeded Monarchs on their migration. The professor assured me this was no a problem as the Monarchs fly high enough.
What he said was a problem was large urban areas the Monarchs travel through on their migration. They are so large and offer so little food sources that the Monarchs have difficulty crossing them before they fatigue.
I can travel those few minutes to the rural areas outside Temple, TX and find milkweed, even along roads next to farms, where Roundup is said to kill milkweed due to spray drift. But I sure don’t find any milkweed in any of those manicured green lawns.
As for fewer California Monarchs making it to Mexico? Well those devastating wildfires caused by poor land management left vast areas of no food or water for migrating Monarchs.
So milkweed adapts to changes in CO2 concentration? Makes sense.
And the testing in a greenhouse proves it.
But Monarch Butterflies cannot adapt to changes in CO2 concentration? That makes no sense.
And there is no testing to prove it.
Evolution is real. These self-proclaimed entomologists should face that fact.
Is anything today different from yesterday? THE END IS NIGH.
We had a substantial hatch and migration here in Western Massachusetts this year.
Monarchs have a thriving static population in the warm top-end of New Zealand. It’s possible to watch the entire life-cycle. Milkweeds are often grown in gardens, parks and cemeteries.
Monarchs can also be seen occasionally in the cooler South Island where they rely on swan plants instead of milkweed.
Just a minute . Monarchs in New Zealand. Monarchs in North America . Does that mean that they have survived since Australasia and the Americas were combined in a Gonwana- Laurasia supercontinent , about 200 million years ago?
Or is the term “Monarch” used indiscriminantly and actually refers to widely different genera .
I suppose they could have been introduced to NZ by travellors from America , perhaps inadvertently aboard a trading vessel .
Yes, they were introduced.
They first arrived in NZ in 1870s..self-introduced.
They island-hopped across the Pacific and through S.E.Asia in the 1800s.
Either came across from Australia or down from New Caledonia.
https://www.abc.net.au/radionational/programs/offtrack/flying-weeds:-how-the-monarch-butterfly-colonised-australia/6768228
Milkweed very common in the Sierras such as Yosemite Valley.
There are about 10 generations of Monarchs per year. That means 800 generations of adaption until 2100 CE. Now lets go back 800 generations of human adaption. Fringe survival, cave paintings in Spain, Neanderthals, Americas very likely unoccupied.
I’m thinking the butterflies will be fine. 200 million years times 10 generations per year of practice and they got it all over us “mayfly hoomins.”
A more simple explanation is that with more CO2 in the atmosphere, their food sources(plants) are doing better and they are responding to more and better quality food?
But wait I forgot there are no positive effects of extra CO2.
Now wait just a damn minute. Farmers are killing off milkweed, the favored habitat of the migrating butterflies, and yet alleged CO2 based GHG warming is responsible for their decline? WTF? Are you authors (I won’t dignify you by calling you scientists) frackin’ (Battlestar Galactica reroll) insane?
Dr. Jim Steele, wet mess cleanup needed at National Geographic.
Milk weed was considered a noxious weed up to a short time ago. In a lot of places you were required to kill it.
My take is bio-fuels are responsible. Too much corn and pesticides. And that’s the heart of it.
And Nat. Geo’s nose is growing longer too because of….