Monarch – Mouse Connection?

Logitech, an innovative company known for its keyboards, mice, webcams and other peripherals for your digital world, has begun using the monarch butterfly in an advertising campaign for their new state-of-the-art MX Air Rechargeable Cordless Air Mouse. Oddly enough, this pairing makes sense – the mouse features orange LEDs against a black body and its “Freespace” motion sensing technology allows you to move the mouse gracefully through the air as you navigate your Mac or PC to listen to music, browse photos, or surf the web. It certainly evokes images of a monarch butterfly in flight…or maybe that’s just me.

If the monarch helps sales, maybe the folks at Logitech would in turn help support a severely underfunded monarch program dedicated to education, conservation, and research…perhaps one whose name begins with “Monarch” and ends with “Watch“? If any Logitech-ians are reading, please feel free to drop us a line!

Overwintering Monarch Population 2007-2008

It’s official – the monarch population numbers are low again. Measured at 4.61 hectares, this year’s overwintering population is the third lowest since detailed measures of all overwintering colonies began in 1993. The three lowest populations in this 15-year record have all occurred from 2000 to 2007 and the mean number of hectares for this interval is 6.3. The mean for the 7-year interval from 1993-1999 was 9.3.

On the surface, the difference between the last 8 years and the first 7 years would appear to suggest that the monarch population is declining. That may or may not be the case. At the moment, we don’t have the capacity to distinguish the impacts of anthropogenic factors (such as the loss of 100 million acres of breeding habitat due to the adoption of Roundup Ready crops, the annual loss of 2.2 million acres in the United States due to development, or the degradation of the overwintering sites) from those attributable to natural causes. The preponderance of evidence suggests that the monarch numbers are largely driven by climate and the lower mean for the last 8 years can be explained by less favorable climatic conditions than those in the 90s.

Based on the climate models I’ve been working on for the last several years, the lower numbers were not unexpected. The unrefined model predicted a total population of approximately 5 hectares, relatively close (as such predictions go) to the final number of 4.61 hectares. For previous discussion of this point see last month’s “Monarch Population Status” post.

How are the monarchs overwintering? It is now the 7th of February and all I can say to this question is: “so far so good”. The winter has been “normal” with most daytime temperatures in the 60s and nighttime temperatures in the 30s; there have been no reports of mortality due to freezes or storms. In another week, around Valentine’s Day appropriately enough, some of the monarchs will begin courting and mating; in the forth week of February some monarchs will begin the long flight back to the breeding grounds in the southern United States.

As to the coming season, will the monarch numbers be up or down? Much will depend on the conditions – primarily the temperatures and nectar availability – the returning monarchs encounter as they move north through Mexico and into Texas.

The numbers of hectares that represent the overwintering monarch populations from 1993 to present are given in the figure below.

Figure: Size of Overwintering Monarch Populations, 1993-2007.

We are indebted to many individuals who have spent long hours measuring the colonies over this 15-year interval, including Eligio Garcia Serano and, in recent years, Eduardo Rendon Salinas and his crews from World Wildlife Fund Mexico. We are also indebted to Carlos Galindo Leal who coordinates the monarch program for WWF-Mexico. The official report on the areas occupied by monarchs for each colony can be downloaded from the WWF-Mexico site (200K PDF file, in spanish): “Monitoreo de las colonias de hibernación de Mariposa Monarca: Superficie forestal de ocupación en diciembre de 2007”

[ Article revised 19 February 2008 ]

Crackdown on Illegal Logging in Mexico

Nibble, nibble, nibble…

Each year illegal logging nibbles away at the forests in the Monarch Biosphere Reserve. These activities originate with local residents in some communities and with outside businesses that hire and organize crews to invade forest plots, often at night, to cut down and remove large numbers of trees in a short period. The larger illegal operations operate boldly in the daytime defying local authorities. From the outside, it looks like the deforestation continues until it can’t be ignored and then the government steps in and raids sawmills, confiscates a few trucks, and arrests a some of the illegal loggers or “talamontes”. This scenario is followed by promises to protect the forest by the government and protection, especially at Sierra Chincua, in the form of the army and special patrols is evident. But then, somehow, the cycle starts again. Illegal logging picks up and continues until some threshold is reached and the government responds.

Shortly after he took office, the President of Mexico, Felipe Calderón, promised to eliminate illegal logging and to protect the Monarch Biosphere Reserve. Illegal logging picked up again last summer but this time it didn’t go unnoticed and as reported by the Associated Press and other news services on and after the 6th of December, the government conducted the biggest sweep of illegal logging operations in the history of Mexico in the vicinity of the Monarch Biosphere Reserve.

The newspaper accounts vary but the facts appear to be the following:

• 19 sawmills and lumber yards were raided.
• Approximately 6,600 tons of logs and lumber were confiscated. The amount of wood products was said to be equivalent to 600 truckloads and over 1,750 mature trees. Most of the forests in the Reserve have tree densities of at least 300 trees per hectare so this harvest represents approximately 5 hectares.
• The raids were conducted by 600-700 police and environmental agents.
• 45-56 loggers (talamontes), mill operators, truck drivers, and others were arrested and charged. The fact that those arrested were actually charged with crimes drew the attention of some commentators in Mexico since charges don’t often follow arrests in these cases.

In the past year, the Mexican government has shut down 59 illegal sawmills and charged 193 people with crimes associated with illegal logging. These raids and the government’s attempts to shut down illegal logging throughout the country are promising. A reduction in the rate of deforestation is badly needed. In 2005-2006, over 574 hectares of the 56,260 hectare reserve were deforested*. Losses at this level (10%) over such a short interval are unsustainable. Hopefully, the rate of loss of forests in the Reserve will slow sufficiently so that natural replacement and reforestation efforts will be able to keep pace with these losses.

*See WWF-MX report (300K PDF, in spanish): “PÉRDIDA Y DETERIORO DE LOS BOSQUES EN LA RESERVA DE LA BIOSFERA MARIPOSA MONARCA 2005-2006”

Janis Lentz standing along side the base of a recently cut old-growth oyamel at San Andres (2004).
Photo by Chip Taylor.

Stump of an old-growth oyamel at San Andres (2004). The widest diameter of this tree was at least 56 inches.
Photo by Chip Taylor.

Oyamel logs cut to length and placed so they could be easily rolled downhill to an awaiting truck.
Photo by Chip Taylor.

2008 Tagging Kits

We are now accepting orders for the 2008 Monarch Watch Tagging Kits. As most longtime taggers know, we have a limited number of monarch tags created each year and demand always exceeds the supply. If you would like to participate in the 2008 season tagging this fall, please place your order for tags as soon as possible so that you don’t miss out. The tags will be mailed out via USPS 1st Class Mail beginning August 1, 2008 – in plenty of time for the migration in your area. Read the rest of this entry »

Pismo Beach Monarch Grove

From time to time (usually during the monarch overwintering period) we receive information about the western monarch population – here is a recent communication regarding the operations at the Pismo Beach Monarch Grove in California.

We have 40 active State Park docents and volunteers working in two-a-day shifts at the grove every day from November 1st to March 1st. We have three “jobs”: (1) selling monarch related items from a portable trailer, grossing over $50,000 per season; (2) roving the grove to answer visitors’ questions; and (3) giving at least two talks per day.

The last two years we have had over 60,000 visitors and expect this year’s total to be even greater.

[Monarch Watch Note: El Rosario is the most visited monarch overwintering site in Mexico and is said to have in excess of 100,000 visitors each season.]

We always check with the other three major California sites – Natural Bridges State Park in Santa Cruz, Pacific Grove, and Ellwood Main in Goleta. We usually have the greatest number of butterflies. That’s true this year, so we are able to tell visitors that they are visiting the largest aggregation of overwintering Monarch butterflies in the U.S.

All western sites are down in numbers this year, we’re currently reporting 19,000 monarchs.

Dr. Dennis Frey, now retired from Cal Poly, has been our resource person for the past 15 years and continues to be a huge aid to us docents.

For more information about the Pismo Beach Monarch Grove visit www.monarchbutterfly.org

New Tree Nursery Near Cerro Pelon

The monarch colonies in Mexico are scattered over a number of distinct mountains. Among these is Cerro Pelon, a mountain near Zitácuaro that harbors 1-3 relatively small monarch colonies each year. Although it ranks as the third most important monarch overwintering location, there has been a significant loss of forests on this mountain over the last decade due to illegal logging. According to Lincoln Brower, a number of former colony sites on Cerro Pelon have been completely logged over.

Before my trip to Mexico last February I learned of a monarch colony known as Aseradero* on Cerro Pelon that had died out early in the winter. I managed to visit the site in the first week in March. The horseback ride to the site took almost three hours and some parts were rough going. Along the route there were signs of recent deforestation and we passed scenes of destruction of older trees with basal diameters of 3-4 feet. No old growth trees were seen. Most of the backside of the mountain, an area seldom seen by visitors, has been deforested. New growth was evident here and there in the cut over areas but natural regrowth was uneven, perhaps because the loggers removed all or nearly all of the seed trees. The colony site consisted of a relatively sparse stand of 10-15 year old oyamels. The trees offered poor cover on a steep and exposed slope most of which had been clear-cut. Yet, the monarchs had settled there and many of them died, apparently after a cold night or two in January. If there were survivors, they had dispersed long before our visit. Why the monarchs chose this location is not clear, it was a poor choice, but this spot was said to be the site of previous colonies. The dead monarchs formed a carpet covering more than 50% of the forest floor in the small area of the colony that we examined. The butterflies were in remarkably good shape. We took pictures of over 200 monarchs with intact wings for a study of the sizes of the monarchs that reached Mexico and then headed down the mountain.

Chip taking pictures of dead butterflies. Photo by Janis Lentz.

Looking out over the valley from the colony site. Photo by Janis Lentz.

On the ride back I tried to ignore the sounds of chainsaws in the distance and I looked for signs of reforestation. Old plastic plant bags were evident here and there and I spotted some seedlings but most were spindly and overgrown. It is a major task to replant these cut over areas and to protect the seedlings until they become well established.

Protecting the remaining forest on Cerro Pelon and reforesting the logged areas will be challenging. Hopefully, this challenge will be met through the development of a new tree nursery known as “Las Novias del Sol” in the indigenous community of San Juan Xoconusco. This community is located in the municipality of Donato Guerra, 40 kilometers from Zitácuaro. The residents have a long history of resisting illegal logging and now they have a chance to restore much of what has been destroyed over the last decade.

The nursery was inaugurated on 8 December 2007. The goal is to produce a total of 800,000 seedlings per year (oyamels, pines, and cedars) that can be planted at different altitudes and slopes in both the core and buffer zones of the reserve. The nursery will have social and economic benefits. By employing 15 full time workers and 30 others during the planting season, the nursery will contribute to the economic and social fabric of the community. Hopefully, the jobs will reduce emigration to the cities and will lead to community directed sustainable forest management.

The initial cost of the project was 874,000 pesos (US$80,000) of which an alliance of WWFMX-and Telcel, a communications giant in Mexico, contributed 682,000 pesos. An additional 192,000 pesos was provided by the Programa de Coinversión Social de la SEDESOL federal and the Secretaría de Desarrollo Social del Estado de México. The community aided in development of the nursery with manual labor and PROBOSQUE contributed a variety of supplies and seed.

This text was derived from an article published by World Wildlife Fund Mexico in December 2007: “Inaugura Comunidad Indígena del Estado de México vivero forestal ‘Las Novias del Sol’”

*Subsequently measured at .244 hectares (Lincoln Brower, pers. com.).

“Monarch River” at Cerro Pelon

Last October, our tagging program was featured in an ABC World News segment (“A Nation on Monarch Watch“). This segment utilized some of my footage (shot in March, 2007) of streaming monarchs at Cerro Pelon in central Mexico. To stand in the “river” of tens of thousands of monarchs as they race down the ravines from the colony at Cerro Pelon on their daily quest for water is one of the most amazing natural phenomena I’ve ever had the privilege to experience.

Monarchs “streaming” at Cerro Pelon. Photo by Chip Taylor.

Movement of monarchs from the colonies to sources of moisture occurs on most warm days during the overwintering period from November through late March. Relative to the total population, the proportion of monarchs engaged in this activity is modest until mid February when the search for water intensifies. From that point onward monarchs “streaming” down from the colonies to moisture sources becomes a common sight. At Cerro Pelon, the butterflies, in what I call the “Monarch River,” are so abundant that you can hear the light clatter of the wings as they rush past at 10-12 miles per hour. If you are standing in the right place (or the wrong one from the butterflies’ point of view) they bump into you frequently as they are going so fast that they can’t always avoid obstructions. The “streaming” starts at 9am on warm clear days, lasting until early afternoon. Once the butterflies have acquired the water they’ve sought, they begin to “stream” uphill at a more leisurely pace, usually taking a different route back to the colonies. The quest for water is frenetic and energetically demanding and seems to take priority over visiting flowers for a source of moisture. The streaming precedes the migration northward and it could help prepare the monarchs for the return migration. Although streaming can last for weeks, it is not clear how long individual butterflies participate in the daily traverses down and back up the mountain.

Video: Monarchs “streaming” at Cerro Pelon, 2007; 30 seconds.

Streaming could serve several functions. The overwintering butterflies are in reproductive diapause and have a low metabolism. This low metabolic rate is under hormonal control, a control that is broken when ambient temperatures increase causing the butterflies to become sexually active. The water seeking activity, with its rapid flight, certainly raises body temperature and could accelerate this process by activating the hormonal cascade that breaks diapause. Further, the water acquired is probably used to metabolize lipids into sugars for flight and to facilitate the development of the latent reproductive organs. At the time these changes are occurring, environmental information is acquired and processed by the monarchs – in a manner as yet unknown. It may be that a genetic cascade is initiated that up-regulates the expression of some genes while down-regulating other genes with the overall effect that the butterflies reacquire the behaviors, five months dormant, needed to migrate northward to reproduce and start the annual cycle once again. We have a lot to learn about this process.

How do the monarchs find water? We don’t really know, but if monarchs are like other insects whose water seeking has been studied, they probably have special receptors for water known as hygroreceptors. Whatever they use, it certainly works. On a Sunday in March near Macheros, the village that leads to Cerro Pelon monarch colony, while filming streaming and water seeking monarchs I noticed a man watering his front “lawn” (mostly dirt with a sparse head of grass). He watered for quite some time and, as each portion of the front yard was watered, monarchs began to settle. By the time he finished watering there were thousands of monarchs in the front yard. Shortly thereafter the first guests arrived for an afternoon party. As each guest walked across the yard to the front door hundreds and hundreds of monarchs took flight around them. It was a delightful sight and I’m sure the rising monarchs were the host’s gifts to his guests and that the water was an intentional gift to the monarchs.

Monarchs watering on moist grass. Photo by Chip Taylor.

Monarchs “streaming” down a ravine at Cerro Pelon. Photo by Chip Taylor.

Map showing the location of streaming monarchs. View Larger Map

Revised 06 Feb 2008.

2007: Unusual Migration & Hotter Than Normal Fall

Tagging has shown that the timing and pace of the migration is generally quite predictable (see “Peak Migration Dates“). The pace of the migration was normal this year as the butterflies advanced from 50 degrees latitude in the north to about 40 degrees in the middle of the country – then the migration appeared to slow. The slowdown corresponded to a prolonged high-pressure system, with hot temperatures over the central portion of the country from late September through most of October.

As you know I’ve given myself the responsibility of trying to interpret monarch numbers on a year-round basis. This task is not difficult and most of the time I can articulate at least a general description of the relative size of the population and can usually explain why the numbers might be up or down. It’s pretty general stuff and subsequent events usually show that I’m not too far off the mark. There are challenges however, and this fall presented one such challenge. Monarch numbers appeared to be above normal once again in the east, although not as numerous as in 2006. Further, it was clear that the numbers of butterflies originating from the upper Midwest were greater than in 2006. Yet there were signs that the population coming through the central portion of the country was below the long-term average for this region.

The progression of the migration through both the central portion of the country and along the coast was unusual. In addition to a slowed migration as mentioned above, relatively low numbers of monarchs were reported from southern Minnesota through Oklahoma, with few exceptions. As this was happening, I was speculating that the monarchs were there but just weren’t being seen or reported. Due to the numbers of observers, much of the migration moves through the Midwest unreported in most years so this speculation seemed reasonable. The number of observers in Texas is much greater and I was expecting large numbers of monarchs to be reported as they moved through that state. It didn’t happen. In addition, the number of monarchs moving along the Gulf Coast from east Texas to Corpus Christi was one of the largest seen in decades.

Our understanding of what happened this fall was greatly enhanced by the efforts of Mike Quinn. Mike is an Invertebrate Biologist at Texas Parks & Wildlife and he has established a substantial network of professional and amateur naturalists that report monarch sightings during both the fall and spring migrations. Mike also marveled at the unusual nature of the monarch migration through Texas and the numerous observations and reports led him to post a summary of the sightings to Dplex-L, a Monarch Watch discussion list. Mike’s summary and analysis is represented below. The only note to add is that Monarch Watch received reports that large numbers of dead monarchs had washed ashore at Galveston and other locations along the coast or were seen flying over the Gulf, emphasizing the hazards of coastal travel.

Each fall, the majority of Texas monarch sightings consistently fall into what we call the Central and Coastal Flyways.Central (and larger) Flyway is generally most active from early to late October.

Conversely, the Coastal Flyway is generally active from mid October to mid November.
Question, are these flyways “real” and if so, why are they not synchronized?

Recapping the fall 2007 monarch migration.
Monarchs start heading south in late August.

By the first week in October, monarchs start crossing the Red River
The monarch front appears somewhat asynchronous at this time.

By mid October, monarchs pour through the Central Flyway.
This major monarch migration corridor generally extends from I-35 to Midland.

During the third week of October, the monarch flow appears to shift to the southeast.
At this time, monarchs occupy portions of the Central and Coastal Flyways.

By the last week of October, monarchs are primarily restricted to the Coastal Flyway.
The Coastal Flyway is more variable that the Central Flyway and is generally active from mid October to mid November.

The relative lack of monarch watchers across the southeastern U.S. contributes to the mystery of the origin of the coastal monarchs, but they likely started in the northeast.

If so, then the greater distance traveled from the northeast might account for the asynchronous timing of the Coastal Flyway, versus monarchs traveling a shorter distance from the Midwest and using the Central Flyway.

If the Coastal Flyway is populated by monarchs originating from the northeast, a potentially significant contributing factor to the delayed flight along this flyway may be the fact that winds rarely blow from the NE to the SW. Therefore, butterflies traveling such a route would encounter more cross winds than monarchs flying through the central flyway.

Some monarchs overwinter along the Gulf Coast. Is it possible that the impetus to continue migrating is lost due to the lateness of their arrival?

Concentrations of monarchs (shown in blue) seen along the Gulf Coast of Texas in late October 2007:

Monarch Roost map graphics created using Journey North‘s Fall 2007 Monarch Roost Maps

Roundup-Ready Crops and Resistant Weeds

One of our justifications for the Monarch Waystation program has been the loss of milkweeds in 100 million acres of row crops* that followed the adoption of Roundup Ready soybeans and corn. In June of 2004 I wrote “Effects of Transgenic Crops on Milkweeds” where I drew attention to this issue and to the rapid development of weeds resistant to Roundup (glyphosate) in Argentina and concluded “Roundup resistant weeds seem to be in our future.” They are here and are spreading rapidly.

Weeds resistant to Roundup are showing up in many areas of the United States. On the 20th of August 2007 National Public Radio aired a report on this topic by Dan Charles (“Farmers Switch Course in Battle Against Weeds”).

When I wrote the June 2004 article, 15 weed species in Argentina were notably resistant to Roundup. According to Dan Charles’s report there are already 13 Roundup resistant species in the United States. We are catching up fast.

Curiously, the use of Roundup is changing the composition of weed communities due to selection that favors species that are naturally resistant to Roundup such as lambsquarters, velvetleaf, giant ragweed, and Asiatic dayflower. Other species, with genetic variants that are resistant to Roundup, are increasing as well. This scenario may apply to wild parsnip, pokeweed, evening primrose, and horseweed – species that are showing up in row crops, a habitat in which they had previously been relatively uncommon.

*Note: Genetically modified seeds for major crops are now the rule, not the exception. In 2007, 92 million acres of corn were planted and of these 61% had been genetically engineered to express Bt toxins to kill or inhibit several types of insects, to resist Roundup, or both. Of the 64 million acres of soybeans planted in 2007, 91% were Roundup Ready. Due to the soy/corn rotation, my interpretation is that we’ve lost at least 100 million acres of milkweeds in these row crops since the first Roundup Ready plants were brought into production in 1996. This is an increase from my earlier estimate of a loss of milkweeds in 80 million acres of row crops. If you find milkweeds in corn or soybean fields, take a picture – it’s now a rare sight.

1,800 Monarch Waystations and Counting

The number of certified Monarch Waystations continues to grow. In 2007, we added nearly 800 habitats to the registry and the total number of registered Monarch Waystations to date is 1,835. We hope to add another 1,000 (or more!) habitats to the Monarch Waystation Registry in 2008 but we need your help!

The growth of the Monarch Waystation Program is clearly dependent on publicity but the publicity has to be at the right time and right place. One year we placed an advertisement promoting Monarch Waystations in a magazine for birders. The cost was not insignificant. Although the publication has a good circulation, the response was very weak. Given this experience and our extremely limited budget, advertising is out of the question and we have to rely on articles about our program in newspapers and magazines to get our message to the public. Last February an article on our program and Monarch Waystations appeared the gardening section of the San Francisco Chronicle:

“Gardeners save the day as butterfly habitats disappear”

The response to this article was overwhelming and in a matter of a few days we had orders for over 1,000 California Monarch Waystation Seed Kits. Articles in Midwest Living, Mother Earth News (“Relief for Weary Monarch Butterflies“) and the Chicago Tribune also generated good responses. However, we can’t count on the media to inform the public of this program every year so we are asking all of you to help spread the word. A number of people with Monarch Waystations have helped promote the program through contributions to online forums and through blogs. Others hand out literature at public events and during educational programs. Bob Morton (Monarch Waystation #613) has a sidewalk garden where he displays the Monarch Waystation sign to which he has attached a “take” box containing brochures describing the value of creating habitats for monarchs. All of these methods are great ways to get the public’s attention. Please help us spread the word!

Our special thanks to all who have participated in this program. We appreciate your continued support of Monarch Watch and monarch conservation.