Well, if the problem has been defined, i.e. reduction of the larval host plant and logging in Mexico, then these need to be addressed. It is for US wildlife activists to persuade their government to increase the area under Asclepias curassavica, or better, indigenous larval host plants in the US and Canada, These are pretty plants and easy to grow, so even people with a bit of space in their backyards can be encouraged to grow this. So far as logging in Mexico is concerned, it is illegal, so pressure has to be put on the Mexican government to apply their laws. Probably the logging is going on in connivance with lower echelon employees of the governmental apparatus. Perhaps we on researchgate should get up a petition to appropriate authorities in the US, Canada and Mexico to address the problem seriously.

Having said that, one should also not ignore the fact that North America has been experiencing some unusual weather, which might have had an effect on the emergence of the butterfly. So it might make sense to wait a few years and see whether this is a natural dip in the population which will level off in a year or two, or whether this is a permanent drop. Remember that insects lay a large number of eggs and when conditions are favourable, the population can increase rapidly to outbreak proportions. Similarly, if one or more conditions are unfavourable, the population can drop sharply, as seems to be the case with the Monarch at the moment. The Monarch belongs to a tropical subfamily, this particular species is probably the northernmost representative of the subfamily, so it is not difficult to understand that it has colonized an extreme habitat, by subfamily standards. The fact that it migrates south rather than overwintering there underscores the fact that it cannot tolerate too much cold. So if there has been even a slight change in some vital parameter (temperature, humidity, etc), it can cause the population to crash. We discovered that a prolonged dry winter in the western Himalaya caused the species diversity of the butterfly community to be reduced almost by half the following season. It was lucky that I had a number of pupae, which all were desiccated, so it was possible to make the connection, else we would have been in the dark about the drop. Needless to say, the population rebounded to normal in the following years.

On the whole, I would suggest a policy of wait and watch. It is very likely that populations will recover in a year or two.

Here is an article from yesterdays paper on the subject.

http://www.washingtonpost.com/blogs/wonkblog/wp/2014/01/29/the-monarch-butterfly-population-just-hit-a-record-low-heres-why/?wpisrc=nl_wnkpm

An interesting paper which gives an insight into the issue probably.

http://www.jstor.org/discover/10.2307/2387997?uid=3737464&uid=2&uid=4&sid=21103320655241

I do think there are natural dips and later outbreaks in populations from year to year. When I was a young butterfly collector and lepiodopteran enthusiast I saw one year in Wyoming when Parnassiinae spp would be very populous some years almost to the point that walking the meadows there would be clouds of them. Then there would be variant years that as I would walk the same habitats and other locations there would be significant declines. These observations of course was made by me, a 9 year old kid on the abundant year and then the anecdotal observations without an organized study. Sadly, I was guilty of collecting bunches of these butterflies so I contributed to providing collection information but the butterflies were sold to The Butterfly Art Jewelry Company where probably there are bunches of paper bodied (real wings) in lamp shades and plastic paper weights that i sold in triangle envelops. This company has long since shut down, the Glanz relaxing fluid was the owners invention and he sold butterflies world wide again as anything as collectors to art jewelry for painted wings (especially Morphids). I regret that I did this but I loved collecting and at the time my meager few hundred butterflies paid for school clothes and school supplies it came in handy I also trapped rabbits and sold their pelts, this is a confession (with deep chagrin and regret) that I want to say none of us are saints and have done our own levels of destruction to the environment and species that live with us . In later years I saw this in many different species of lepidoptera and other insects with dips and outbreaks of populations and suspect that the abundance of food sources, changes in precipitation, cycling of diseases and parasitoids and even adequate protected areas, to pupate from predation (ie grizzly bears eating pupa under rocks in late fall for supplementing dietary needs prior to hibernation). I DO NOT want to dismiss or reduce the impacts of urban sprawl or of the illegal logging of areas that are the monarchs refuge especially when there are only the California and Mexican locations (though some have postulated that there is an additional migration location unknown at this time). I think that learning more about its migration habits such as locations in the U.S and Canada and determining factors of reduction that can be documented and acted on. Some aspects as the number of monarchs i notice in parking lots in the grill of vehicles. So many factors are out of our hands and there are and will be continue rampant reductions and extinctions. We are and have been poor stewards of our little blue globe, with past examples of mass huntings and collectings to the point of extinction or endangerment. Some in the desire to have rare and exotic creatures before they disappear, sad commentary on what we should see as fellow species that even share some of our DNA. Most of all and lastly we as citizens need to encourage the populace to understand and appreciate what naturalists and scientists both amateur and professional studies yield to the body of knowledge of preservation or even understanding the organisms that my soon be extinct or endangered. One of the greatest concerns I have when judging science fairs is the uncorroborated websites spewing junk science as a popularization with flagrant dishonesty and exaggeration of science studies. The students are quoting sites ie John Doe's site on geology.com (fictitious). I encourage students to be constantly discriminating of information insuring that the websites are from sources such as .edu or .gov then to some extents .org and even then they have to try to sort out the hype from fact, politically engendered and popular hype. We all love big beautiful animals but have a hard time loving some endangered slug, or insect. All this of course is my personal view and should not reflect the views of my employer.

Franklin, please excuse the diversion from your question, but, Leslie, I am most interested in your observations about the population outbreaks in N. American Parnassini. May I request you to please share your observations? I am doing a paper on Himalayan Parnassini, and your observations seem to be valuable, regardless of the fact that they were not quantified. If it is ok with you, if I use them, I would be happy to add you as a co-author of the paper.

D. plexippus was incredibly common this year in Central Mexico! Surely highest number since 10 years....

It means that without understanding why...migration didn't occur normally this year and most of population was staying as resident.

Normally D. plexippus is very rare (resident population) during rain season in Morelos/Guerrero and very common only from late November to February (migrants). This year it was very common all the year.

What was disturbing migration is more the real problem.

Given all the inclement weather, it is not surprising that migration did not happen! I wouldn't have gone north this season, either! :)

It seems to be as interesting as the phenomenon of animals retreating before the tsunami struck India some years ago, so that although there were a great number of human casualties, there were hardly any animal casualties.

Thanks everyone for sharing this enlightening conversation among persons more knowledgeable on this topic than I am. As a human ecologist, I am torn between the notion that we may be looking at a phenomenon similar to the proverbial "canary in the coalmine", and yet agreeing with the notion that we maintain a policy of "wait and watch", for a few more seasons. As an applied scientist however, I have a inherent drive to link research with (at least) the potential for action. Indeed, action may already be justified on the basis of "prudence", even as more evidence about what is actually happening comes to light. Clearly there seems to be a legitimate basis for action regarding the illegal logging in Mexico, the need for better land conservation practices and setting more rigorous protective limits on industrial scale agriculture. Interestingly, with regard to climate change as one potential explanation, I have been engaging in another RG conversation regarding the northward (and southward depending on the hemisphere) expansion of vector-borne diseases of importance to humans. Participants might find the "one health" initiative to be of relevance here, as a unifying concept. To check this out, visit: http://www.onehealthinitiative.com/

Dear Franklin

Real situation in Michoacán (Main site for D. plexippus in Mexico) is much more complex than just "illegal logging". Of course, this is a reality but as you may know this state was becoming the most dangerous of the country with many problem between Narcos, Army/Police(s) and citizens. As the monarch represents money....it is now in the middle of all these conflicts and I'm not fully convinced that logging is the main (or sole) threat.

Thanks Luc for this insight. Complexity lies at the core of most global challenges. In this instance, the overlaps between insect ecology, conservation ethics, greed, environmental management, criminality, and drug dependency (a human health challenge), not to forget climate change and the realities of economic development, all seem to come together to illustrate this.

As a species, is it likely that humans have the ability to resolve all this? Certainly we will not succeed if we stay locked within our disciplinary silos; leadership seems to be the missing element, but where will it come from in this instance? Tipping point?

I could not access this article.

Some evidence of global leadership may just have emerging from this weeks summit involving the USA, Mexico and Canada. See the AP report pasted below:

MEXICO CITY (AP) — Mexico, the United States and Canada have agreed to form a working group on the conservation of Monarch butterflies, whose numbers fell to record lows this year at their wintering grounds in central Mexico.

Mexican President Enrique Pena Nieto announced the decision Wednesday at the end of a one-day summit with U.S. President Barack Obama and Canadian Prime Minister Stephen Harper.

Experts say the butterflies' annual migration from the United States and Canada is in danger because of extreme weather, habitat loss due to deforestation and the displacement of milkweed, the Monarchs' main food source.

Pena Nieto did not announce any specific measures.

The World Wildlife Fund in Mexico called the announcement an important step, but said concrete measures are needed to protect the butterflies' habitat.

Source: Associated Press (AP) February 22, 2014. http://bigstory.ap.org/article/mexico-us-canada-work-monarch-butterflies

The monarch butterfly decline appears to be a real and consistent phenomenon both east and west of the Rocky Mountains. In Mexico, monarchs only occupied 7 of 17 overwintering sites this winter and have declined from a measured high of 21 hectares to this year's 0.67 hectares. In California measurements of monarch overwintering numbers show a decline from 1.2 million to less than 200,000. These trends are likely to be the result of overwintering forest loss and degradation and milkweed habitat changes. Perhaps the most important mitigation that could be changed quickly would be for the EPA to revise its risk assessment policy to measure risk appropriately. Rather than use a value of risk (R), they should show the impact of different levels of R on the life history of target species like the monarch butterfly. The issue of monarchs and Bt corn is a good example. The EPA concluded that risk (R) was negligible because the value was low. Even when the value was recalculated to more than 10 times higher, it was still "low" and so assumed not to be at risk. But what do the values mean? In the USA use of corn for biofuel has dramatically increased corn acreage and increased corn prices. Farmers love herbicide resistant corn and the combination of GM corn and increased acreage results in loss of milkweed and many other plant species important to a wide range of pollinator species as well as valuable natural enemies of pests.

Lastly, please, please don't suggest planting Asclepias curassavica as a way to increase milkweed biomass for monarch use - this is a potentially invasive weed, that is attractive and very easy to grow. It has a different latex system and seems to have an impact on a monarch pathogen. But the bottom line is North American monarchs should have almost no access to this species and we don't know the impact of this species on monarch life histories - for example the plant flowers continuously and is likely to break reproductive diapause of monarchs, so rather than put on fat in fall, they will try to lay eggs - a good example of this is the impact of the A. curassavica planted in downtown Chicago that autumn migrant monarchs find and the presence of perfect plants, when all native milkweeds are senescing, starts to play havoc with monarch endocrine cycles.

Thanks for providing some data, Steve.

Recent article onTyrone Hill, frogs, atrazine, Syngenta and the EPA in the New Yorker shows how political these environmental policy decisions are when billions of corporate profit are at stake.

I agree that modifying the environment with cultivated milkweeds is not the way to stave off the natural catastrophe that seems to be occurring.

Thanks Andy! I hate to add to the list of problems, but even where there are existing regulations they are ignored because there is no, or limited, implementation by USDA (perhaps understandably through budget cuts) - for example, GM crops are supposed to be planted with a non-GM buffer to slow the evolution of resistance genes. But when we tested this in corn we found that in Michigan farmers usually don't bother and everything in the field is planted as Bt corn. This means that in addition to the evolution of resistance genes, the risk to non target species such as monarch butterflies is higher than most estimates show.

Colleagues: a positive development on this issue.

Three days ago, the US Government announced financial support to help save the monarch butterfly.  The following extract has been clipped from a PBS report by  Dina Cappiello, AP February 9, 2015 at 3:25 PM EST.  URL: http://www.pbs.org/newshour/rundown/u-s-government-pledges-3-2-million-save-monarch-butterfly/

WASHINGTON — The federal government on Monday pledged $3.2 million to help save the monarch butterfly, the iconic orange-and-black butterfly that can migrate thousands of miles between the U.S. and Mexico each year. In recent years, the species has experienced a 90 percent decline in population, with the lowest recorded population occurring in 2013-2014.

About $2 million will restore more than 200,000 acres of habitat from California to the Corn Belt, including more than 750 schoolyard habitats and pollinator gardens. The rest will be used to start a conservation fund — the first dedicated solely to monarchs — that will provide grants to farmers and other landowners to conserve habitat.

The move by the U.S. Fish and Wildlife Service comes as it’s in the midst of a one-year review to determine whether to classify the monarch butterfly as a threatened species under the Endangered Species Act, which would afford the butterfly more protection. In December, the agency said that there was enough evidence to trigger a review.

Dear Franklin

Thankfully this year migrating Monarchs are, at least, 3 times more abundant than these last years in Michoacán/Estado de Mexico.

It seems that we are far to understand everything !!!!

Nice that some funding is planed. It will help anyway.

Cheers from Luc

Thanks for your observations Luc, most welcome.

I agree there is more complexity in this issue, than we can fully understand.

We must remain on guard for the Monarch. As the political dictum goes: "The price of freedom is eternal vigilance."  And a butterfly species cannot be responsible for such vigilance.  So we humans, a flawed species, must remain vigilant for the Monarch.

Moving now from one species to another (perhaps from one extreme to another), with "one health" and the role of human behaviour in mind, perhaps you may wish to comment on another question I have posted, on the plight of the rhinoceros?

You can locate this on my RG page.  Any early comment would be most welcome. 

Best wishes.

The following report is extracted verbatim from Bird Studies Canada Latest News - 7 August 2015