Since the issue does not seem to want to fly away, we set out to determine where the controversy came from and what scientific research has been completed since this topic first migrated onto the scene. We reviewed the most recent, relevant studies on the topic. We then offer our suggestions for ongoing implications the scholarly duels about monarchs might have for those marketing fresh produce.

 

In short, here's what we found: the butterfly scholars are still dueling. The older controversy (1999) about the effects of GMO corn pollen on monarch larvae seems to stand as a good reason never to conclude too quickly that the sky may be falling. Currently, there is agreement that the monarch butterfly's prime habitat (milkweed) in the U.S. has declined due to the widespread use of glyphosate-resistant corn and soybeans. However, the jury appears still out on whether or not this decline in habitat is actually affecting overall monarch populations. One 2011 report suggested that monarch populations are declining, while another suggested the data were too close to call.

 

The Origins of the Controversies

Controversy over monarchs and GMOs can be traced back to research reported by Cornell University scientists in 1999(ii). Bt-corn had been approved for farm use in 1995, and the Cornell researchers found that pollen from Bt-corn plants could kill monarch butterfly larvae in the lab. (Bt-corn, of course, is corn genetically engineered with genes from Bacillus thuringiensis to combat European corn borer, an insect pest of corn in the Midwest.) The research was published in no less than the journal Nature.

 

Killing monarch butterflies with GMO corn pollen was not a particularly popular idea. The average consumer tends to like butterflies, and annual monarch migrations are nothing short of spectacular. Groups in opposition to GMOs netted the report from Nature into their public relation arsenals, and the media firestorm began.

 

A few months later in 1999, other scientists at Cornell pointed out that the researchers had been feeding the monarch larvae such high levels of GMO pollen that it was no wonder the larvae died. Said one scientist at the time, "If I went to a movie and bought a hundred pounds of salted popcorn, because I like salted popcorn, and then I ate the salted popcorn all at once, I'd probably die. Eating that much salted popcorn simply is not a real-world situation, but if I died it may be reported that salted popcorn was lethal....The same thing holds true for monarch butterflies and pollen. Scientists have a duty to be incredibly responsible for developing realistic studies. Scientists need to make assessments that are pertinent to the real world."(iii)

 

 

A flurry of research ensued, including efforts coordinated between scientists, corn seed companies, and government regulators. Environmental and consumer food groups seized the opportunity to continue their PR blitz and public protests, pollinating the issue with additional complexity. In the end, the science said that Midwestern corn pollen from the Bt varieties approved for use at that time was not killing the monarchs. Bt-corn continued development and new varieties were approved for release as seeds.

 

But the new confluence of streaming electronic media, concerns about GMO food crops, and dueling scientific scholars highlighted a changing food policy environment in America. The prominent Pew Initiative on Food and Biotechnology released a report three years after the controversy's origins summarizing the monarch/Bt-corn controversy impacts on how science, industry and the public interest interact.(iv)  

 

So were monarch butterflies ready for pinning and mounting in the history of science and food policy? Not quite.

 

From New York to Iowa

While the monarch controversy initially lit from various spins on research conducted in New York, one must land in Iowa to determine the issue's current nature. For a related question, in light of some current claims about declining monarch populations is this: are there fewer milkweeds, the monarch's prime habitat, in Iowa and other Midwestern states?

 

A report published in 2010 by an Iowa State University agronomist clearly documented the reduced incidence of milkweed from 1999 to 2009. This research reported that:

 

• Common milkweed was present in only 8% of Iowa soybean and corn fields in 2009 compared to 51% in 1999.
• The total area occupied by common milkweed in infested fields declined by 90% from 1999 to 2009.
• Widespread use of glyphosate is likely a main factor in the reduction of common milkweed.(v)

This makes good sense to us. Glyphosate kills milkweed, and glyphosate has been sprayed on most corn and soybean fields in the Midwest during the past decade as farmers utilize glyphosate-resistant feed crops. But can the decline of the monarch's main habitat, the milkweed plant, be absolutely linked to reduced monarch populations? And are monarch populations actually reducing? That was the question for 2011.

 

Where the Debate Lands Today

Last year (2011) saw yet more jousts between monarch scholars. A research report in the journal Insect Conservation and Diversity reportedthat during the 2009-10 overwintering season "the total area in Mexico occupied by the eastern North American population of overwintering monarch butterflies reached an all-time low. Despite an increase, it remained low in 2010-11."(vi)  The report cited factors causing the observed decline as degradation of forest in overwintering areas, loss of breeding habitat (from milkweed declines and land development) in the U.S., and severe weather patterns.

 

Meanwhile, the same journal published a report last July that studied trends in monarch populations from two fall monitoring stations in the U.S., in New Jersey and Michigan, during the past 15 years.(vii)  That research found no significant trend in average monarch numbers counted over time. In other words, the number of monarchs on their way from the U.S. to Mexico in the fall has not been observed to be in decline. It stated:

"Even though it is difficult to imagine how monarchs will fare in the future with so many threats to their population, the data presented here suggest that the population remains stable for now, probably because of the high fecundity of the species and its ability to rebound from small winter numbers." 

 

Our Observations and Implications for Produce Marketing

Are monarchs dying from eating Bt-corn pollen? No, that controversy was put to rest a decade ago. Has the monarch's habitat in both the U.S. and Mexico been influenced by disappearing milkweed populations? Most probably-but whether that is affecting the overall monarch population in North America is still being debated. And are monarch populations in steady decline? The dueling scholars with their conflicting research reports in 2011 indicate that it is too soon to tell.

 

Until more data are established, it seems risky for marketers of non-GMO produce to publicly ride the wings of the ongoing monarch debate. The consumer preferring non-GMO, or the customer philosophically opposed to the production of genetically modified crops, is likely to already be familiar with the monarch controversy. For shippers of non-GMO produce wanting to highlight potential effects of GMOs upon monarchs, a sounder strategy might be to simply point consumers to reliable reports from the popular or scientific press updating the research debate. Such consumers are a highly-interested group that will appreciate such information, and social media make it fairly easy to present information for customers merely to consider.

 

As one 2011 study pointed out, the monarch butterfly may prove remarkably resilient and adapt to the changes in its habitat. We also note reports in the U.S. farm press of weeds developing resistance to glyphosate. Could there be a possibility for glyphosate-resistant milkweed? That seems a question unaddressed to date that may prove relevant to the monarch controversy.

 

Finally, we think the whole monarch issue underscores the complexity, adaptability and flat-out wonder of the natural biological systems that we in the fresh produce industry rely upon and work with for our livelihood. Communicating to our consumers the many ways we and our clients work within the natural systems and their awesome phenomena, such as the beauty of migrating monarch butterflies, seems a sound strategy no matter how this debate plays out.

 

[i] Pollack, Andrew. "In Midwest, Flutters May be Far Fewer." The New York Times. July 11, 2011.http://www.nytimes.com/2011/07/12/science/12butterfly.html?pagewanted=all

 [ii] "Toxic pollen from widely planted genetically modified corn can kill monarch butterflies, Cornell study shows." http://www.news.cornell.edu/releases/May99/Butterflies.bpf.html

 [iii] "Two leading researchers take issue with three recent studies on the effects of genetically

engineered crops." http://www.news.cornell.edu/releases/Sept99/Shelton.monarch.bpf.html

 [iv]"Three Years Later: Genetically Modified Corn and the Monarch Butterfly Controversy."

Pew Initiative on Food and Biotechnology.

http://www.pewtrusts.org/uploadedFiles/wwwpewtrustsorg/Reports/Food_and_Biotechnology/

vf_biotech_monarch.pdf

[v]Robert G. Hartzler. (2010), Reduction in common milkweed occurrence (Asclepias syriaca)

occurrence in Iowa cropland from 1999 to 2009. Crop Protection.

http://dx.doi.org/10.1016/j.cropro.2010.07.018

[vi] BROWER, L. P., TAYLOR, O. R., WILLIAMS, E. H., SLAYBACK, D. A., ZUBIETA, R. R. and

ISABEL RAMÍREZ, M. (2011), Decline of monarch butterflies overwintering in Mexico:

is the migratory phenomenon at risk?. Insect Conservation and Diversity.

doi: 10.1111/j.17520in

 [vii] DAVIS, A. K. (2011), Are migratory monarchs really declining in eastern North America?

Examining evidence from two fall census programs. Insect Conservation and Diversity.

doi: 10.1111/j.17520in