With gratitude to WRPN Women’s International Film Festival for this honor
Dear Friends of Beauty on the Wing,
I hope you are all doing well and fortunate enough to have good health.
After a brief cold snap we are having a beautiful Indian Summer here on Cape Ann. I hope you have the opportunity to get outdoors today and enjoy nature. Bird and butterfly migrations are well underway. At Parker River National Wildlife Refuge, rangers shared that they have never seen a migration such as this year’s, with over 180 species sited at the refuge this past week. The birds appear to have benefitted from decreased human activity over the past seven months. On the other hand, the Atlantic Coast Monarch migration seems stalled or nonexistent. Perhaps we will have a late, great migration as we did several years ago. And there are some positive signs for the butterflies, especially through the Mississippi Flyway as Monarch Waystations further north, such as the one at Point Pelee have been reporting that the Monarch migration is doing well. I’ve seen Monarchs migrating through Cape Ann in good numbers as late as the second week of October, so we’ll be ever hopeful.
Good news to share -the page for Beauty on the Wing is up on American Public Television World Wide! Here is the link, including information with a link on how to license Beauty. The page looks great and the line-up of films, stellar. We are so honored to be included in this fine catalogue of Science, Health, and Nature Programming!
And more super good news to share – Beauty on the Wing has been accepted to the Boston International Kids Film Festival! This is an outstanding festival for kids, by kids, and about kids and is organized by a dynamic group of women: Laura Azevedo, Kathleen Shugrue, and Natalia Morgan. A complete list of films for the 2020 BIKFF will be posted in the upcoming days, along with information on how the festival will be organized for safe viewing during the pandemic.
I have been following (or become enchanted is a more accurate description) a small flock of Bobolinks. Click here to read a story posted on my website: Bobolinks Amongst the Sunflowers. While reading about Bobolinks, I came across a link to The Bobolink Project, a truly worthwhile organization. The Bobolink Project habitat conservation plan not only helps Bobolinks, but many species of declining grassland birds.
The sun is coming out and the temperature still summery. Stay well and enjoy the day!
Winds from the north brought a tiny kaleidoscope of Monarchs to our shores over the weekend. Isn’t that a wonderful official word for a group of butterflies! A bunch of caterpillars is officially called an army.
Will there be more waves of Monarchs passing through? Time will tell. Along the Atlantic Coast Flyway, we’ve seen far fewer butterflies so far this year, especially when compared to last year’s numbers. Keeping my hopes up though 🙂
Female Monarch depositing egg on Common Milkweed (Asclepias syriaca)
Evaluating the Migration Mortality Hypothesis Using Monarch Tagging Data
Frontiers in Ecology and Evolution
August 7, 2020
Orley Talor, Department of Ecology and Evolutionary Biology, University of Kansas, Lawrence, KS, United States
John M. Pleastant, Department of Ecology, Evolution and Organismal Biology, Iowa State University, Ames, IA, United States
Ralph Grundel, U.S. Geological Survey, Great Lakes Science Center, Chesterton, IN, United States
Samulel D. Pecoraro, U.S. Geological Survey, Great Lakes Science Center, Chesterton, IN, United States
James P. Lovett, Monarch Watch, Kansas Biological Survey, University of Kansas, Lawrence, KS, United States
Ann Ryan, Monarch Watch, Kansas Biological Survey, University of Kansas, Lawrence, KS, United States
The decline in the eastern North American population of the monarch butterfly population since the late 1990s has been attributed to the loss of milkweed during the summer breeding season and the consequent reduction in the size of the summer population that migrates to central Mexico to overwinter (milkweed limitation hypothesis). However, in some studies the size of the summer population was not found to decline and was not correlated with the size of the overwintering population. The authors of these studies concluded that milkweed limitation could not explain the overwintering population decline. They hypothesized that increased mortality during fall migration was responsible (migration mortality hypothesis). We used data from the long-term monarch tagging program, managed by Monarch Watch, to examine three predictions of the migration mortality hypothesis: (1) that the summer population size is not correlated with the overwintering population size, (2) that migration success is the main determinant of overwintering population size, and (3) that migration success has declined over the last two decades. As an index of the summer population size, we used the number of wild-caught migrating individuals tagged in the U.S. Midwest from 1998 to 2015. As an index of migration success we used the recovery rate of Midwest tagged individuals in Mexico. With regard to the three predictions: (1) the number of tagged individuals in the Midwest, explained 74% of the variation in the size of the overwintering population. Other measures of summer population size were also correlated with overwintering population size. Thus, there is no disconnection between late summer and winter population sizes. (2) Migration success was not significantly correlated with overwintering population size, and (3) migration success did not decrease during this period. Migration success was correlated with the level of greenness of the area in the southern U.S. used for nectar by migrating butterflies. Thus, the main determinant of yearly variation in overwintering population size is summer population size with migration success being a minor determinant. Consequently, increasing milkweed habitat, which has the potential of increasing the summer monarch population, is the conservation measure that will have the greatest impact.
Since the late 1990s, the monarch butterfly, Danaus plexippus, population has declined significantly based on measurements made at the Mexican overwintering grounds (Brower et al., 2011; Semmens et al., 2016). Identifying the cause or causes of the decline is important in order to focus conservation measures appropriately. Two explanations for the decline in the size of the overwintering population dominate the literature. The first, known as the “milkweed limitation” hypothesis, posits that the decline in the number of milkweed host plants in the major summer breeding area in the Upper Midwest of the U.S. (Figure 1) has led to a reduction in the size of the migratory population (Pleasants et al., 2017). The second, known as the “migration mortality” hypothesis, posits that the resources and conditions during the fall migration have declined resulting in an increase in mortality during the migration and a decline in the overwintering population (Agrawal and Inamine, 2018).
Figure 1. All wild-caught butterflies tagged from north of 40° latitude and east of 100° longitude were included in the study. This area includes the region we are calling the Midwest, encompassing the area from 40 to 50° latitude and 80 to 100° longitude (outlined in red) and the region we are calling the Northeast, encompassing the area from 40 to 50° latitude and 65 to 80° longitude (outlined in blue). What we are calling the Total Area is the Midwest and Northeast combined. The NDVI values (Saunders et al., 2019) come from the region that encompasses the area from 30 to 40° latitude and 90 to 105° longitude (outlined in green). The dark blue square indicates the location of the overwintering colonies. Butterflies were tagged in other sectors besides the Midwest and Northeast but those data are not included in this study.
The milkweed limitation hypothesis is supported by data showing that in the early 2000s the majority of monarch production came from common milkweed, Asclepias syriaca, in corn and soybean fields in the Midwest (Oberhauser et al., 2001) and that the abundance of those milkweeds declined precipitously due to glyphosate herbicide use in those fields (Pleasants and Oberhauser, 2013; Flockhart et al., 2015; Pleasants et al., 2017; Thogmartin et al., 2017a; Saunders et al., 2018). The loss of the milkweeds from corn and soybean fields began in the late 1990s with the adoption of glyphosate-tolerant crops. Milkweeds had been nearly eliminated from these fields by 2006 (Pleasants, 2017). During this period, an estimated 71% of the monarch production potential of milkweeds on the Midwest landscape was eliminated, amounting to 25 million hectares of agricultural habitat that no longer had milkweeds (Pleasants, 2017). The subsequent decrease in the availability of milkweed is thought to have limited the size of the summer breeding population. Support for this hypothesis comes from the pattern of decline in milkweed availability that parallels the decline in the size of the overwintering population (Pleasants et al., 2017). Further support comes from the strong correlation between yearly late summer Midwest monarch egg production and yearly overwintering population size (Pleasants and Oberhauser, 2013; Pleasants et al., 2017).
In thinking about where have all the butterflies gone, I am reminded of the poignant song written by Pete Seeger “Where Have All the Flowers Gone,” which although a song about the futility of war, sums up much about the environmental impact of habitat loss. Without wildflower habitat, there will be no pollinators of any sort.
Where have all the flowers gone?
Long time passing
Where have all the flowers gone?
Long time ago.
Where have all the butterflies gone? Different species of butterfly populations fluctuate from year to year. For example, some years you may see far greater numbers of Buckeyes, the next year not so much. That same year you may hardly see any Tiger Swallowtails but will the following.
That being said, everyone must realize that every year there are fewer butterflies than the year before. Butterflies thrive in meadows, the very same topography that is the easiest to build upon. Every time a new house or shopping mall is built on a meadow, we decrease not just butterfly habitat, but a whole community of wildlife habitat.
In the above photo you can see a Monarch with a Black Swallowtail flying overhead. This stunning patch of wildflowers and nectar plants was sited in Gloucester at a prime spot for Monarchs to rest and refuel after migrating across Massachusetts Bay. The new home owners ripped out most of the wildflowers and planted the site in a more formal style, with non-native perennials and shrubs. At this location, I would often see Monarchs, Tiger Swallowtails, Black Swallowtails, Painted and American Ladies, Sulphurs, and many other species. That is no longer true.
Tiger Swallowtail drinking nectar from Joe Pye-weed at the same wildflower patch, no longer in existence.
Butterfly and bee populations are declining overall, not only because of habitat loss, but because of the unbridled use of herbicides and pesticides in agriculture and home lawn care.
Butterflies are especially sensitive to fluctuations in weather, and also to overall climate change. This year we had a long, cold wet spring. The inclement weather is continuing, too, from a butterflies perspective, because although we are seeing some warmer temperatures the past few days, it has mostly been rainy, foggy, or overcast. Butterflies thrive during long stretches of sunny, hot weather. Their wings don’t work very well in the damp and cold. Because of global climate change, we have seen a seven percent increase in precipitation worldwide.
One of the best years I have ever seen for dozens and dozens of species of butterflies, including Monarchs, in the Northeast, was the summer and fall of 2012. That year, we had a warm winter followed by a warm spring, then a warm, dry summer, and a long, warm Indian summer. It was butterfly bonanza that summer and autumn!
Adding to people’s concern is the fact that last year, there was an abundance of spring rain that in turn created an extraordinary wildflower bloom in Texas, which got all the butterflies off to a good start. In 2019, we were seeing Monarchs as early as early June, which was very unusual for Cape Ann. Folks are comparing this year to that of 2019, however, 2019 was not an average year.
Monarchs are a case unto themselves. Their spring and summer numbers largely depend upon an additional variety of conditions, including how successful was the previous year’s autumn migration, whether or not there were nectar providing wildflowers on their northward and southward migrations, and wind and weather conditions all along their route, from Canada to Mexico.
Particularly in the northeast, the wind patterns during the Monarchs spring northward migration matter tremendously. My friend Charmaine at Point Pelee, in southern Ontario, which is 49 degrees latitude (we are 43 degrees latitude) has been raising and releasing Monarchs for over a month now, while most of us on Cape Ann have only seen a smattering. The Monarchs moved this year in a straight northward trajectory. If the wind does not blow from west to east during some part of their northward migration, far fewer will end up along the eastern shores.
All is not lost. I am 90 percent certain we will soon be seeing some of our migratory and non-migratory local populations, we just need some good weather. They are later than usual, but not gone entirely.
For so many more reasons, I am hopeful for the future of wildlife and their habitats and see such tremendous, positive change. Despite the current administration’ s extremely harmful stance against the environment, many, many individuals and organizations are gaining a deeper appreciation about the importance of habitats and taking positive action. Many have made it their life’s work. These individuals and organizations are creating wildlife sanctuaries and conserving existing habitats. If the Monarch is declared an endangered species, that will surely bring an added awarenesses and increased federal spending for protecting and creating habitats.
How can you help species such as the Monarchs, which in turn will help myriad species of other butterflies and pollinators)? Plant wildflowers! Both Marsh and Common Milkweed for their northward migration, and lots of nectar-rich later summer blooming wildflowers for their southward migration, including New England Aster, Smooth Aster, Purple-stemmed Aster, Seaside Goldenrod, and Canada Goldenrod.
Overjoyed Beauty on the Wing has been accepted to the New Haven Documentary Film Festival!
2019 Honors Filmmaker
Our last little Monarch to emerge struggled to gain the warmth needed for takeoff. What is the minimum air temperature needed to allow Monarchs to fly? When at Cape May several weeks ago and witnessing a large overnight roost of butterflies, the air temperature the following morning was the same as Gloucester’s temperature this morning–low forties–but the sun was shining. No sunshine today, combined with the low temperature, made flying impossible. Monarchs cluster together in overnight roosts for warmth. Our little guy was all alone on an isolated branch and with temperatures expected to dip into the mid thirties, I brought him indoors for the night.
Why the late season stragglers? Warmer than usual fall temperatures allowed eggs and caterpillars to reach maturity when in colder years, freezing temperatures would have prevented development
Some Monarchs begin migrating southward as early as August. And as we have seen, during the warm fall season of 2017 in particular, as late as November. The Monarch migration continues until halted by freezing temperatures. This staggered migration is yet another chapter in the survival strategy of the Monarch’s life story. If all Monarchs began migrating at exactly the same time, a powerful storm or hurricane, such as Harvey or Irma, could have devastating consequences on a great many Monarchs.
Today, November 13th, a Monarch will emerge from its chrysalis in a garden 2,800 miles north of its winter sanctuary. The thing is, Monarchs typically arrive in Mexico at harvest time and around Day of the Dead celebrations, or when Americans celebrate Halloween. In the language of the indigenous Purépecha peoples, the name for the Monarch is “Harvester” butterfly. Under the most ideal conditions, this Monarch won’t arrive until Christmastime.
Along the northern leg of his journey, he will find little or no nectar plants as we have had several nights of freezing temperatures. All the wildflowers and garden plants have finished blooming for the season. With little fortification, is it possible for Monarchs to fly great distances? Biologists look for this type of climate change mismatch to track how global warming is affecting wildlife. Butterflies can survive rain. The water beads up and drips off its wings, but snow and below freezing temperatures are fatal to Monarchs.
With a hope and a prayer, fair winds and good weather, perhaps our little intrepid Monarch will make it to sunny Mexico, or possibly, shorten his journey, and at least make Florida his home for the winter. Here’s hoping.
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WITH THE GREATEST APPRECIATION FOR OUR COMMUNITY OF FRIENDS AND SPONSORS, I AM OVERJOYED TO SHARE THAT TO DATE WE HAVE RAISED $23,960.00 FOR THE DOCUMENTARY FILM “BEAUTY ON THE WING” ONLINE FUNDRAISER!
Friends of the Monarch Butterfly: If you would like to help towards the completion of the documentary film Beauty on the Wing: Life Story of the Monarch Butterfly, please consider making a tax deductible donation here:
Donors contributing over $5,000. will be listed in the credits as a film producer.
For more information, visit the film’s website here: Monarch Butterfly Film
For an overview of the film’s budget, please go here: Budget
Thank you so very much for your help.
Whirlwind trip to Cape May to check on the late, great Monarch migration of 2017. Leaving at 5am, from Gloucester, it is an eight to nine hour drive. I spent the afternoon and evening there and then left the following day at noon. Although brief, I found all that I was looking for and much, much more. There are vast areas of wildlife habitat along the southern New Jersey coastline and so many beautiful connections between Cape Ann and Cape May; I would love to return again soon!
The Monarchs are in trouble. I am hoping with all my heart that the tens of thousands that are currently held back by winds blowing from the wrong direction, along with intermittent inclement weather, will be able to cross the Delaware Bay as soon as possible. Will write much more this weekend after catching up with work and after I am able to sort through photos.