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A 10,000 Foot View of Monarch Conservation

Apr 05, 2018


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Monarch conservation has a rich history of science, discovery, and partnerships that has led us to today. As monarchs continue to face complex challenges in our changing landscape, it is important to understand where we’ve been and where we are headed.

In the February 2018 Monarch Conservation Webinar, Monarch Joint Venture Coordinator Wendy Caldwell laid out this framework for understanding monarch conservation. In this article, we share Wendy’s main points and provide resources for digging deeper. You can see the recorded webinar on our website, or keep reading to see the abbreviated story in written form.

A review of population trends for eastern and western monarch populations

Monarch populations are facing dramatic declines across the continent. Measurements of the eastern population have been reported since the mid-1990s. A record high measurement of over 18 hectares of area occupied at their Mexican overwintering sites was documented in the winter of 1996-1997. A few years ago, the population reached a record low of 0.67 hectares of area occupied. While monarch numbers today are higher than the record low, the population is still well below the 20 year average and below the population size which researchers have deemed safe.

Western monarchs have also experienced significant decline. In the 1980s, the western population is estimated to have been as high as 10 million butterflies. In 2017-2018, the Western Monarch Thanksgiving Count showed fewer than 200,000 butterflies at California overwintering sites. While recent counts have yielded a seemingly consistent population size between 200,000-300,000 butterflies, it is important to note that with time, the number of sites monitored has increased. With more effort, one would expect monitoring to result in more butterflies, which has not been the case.

Graphs of the eastern and western monarch butterfly populations

How did we get here?

Monarchs face a multitude of human-induced threats, such as loss and fragmentation of habitat, the widespread use of pesticides, and more. Habitat loss is one of the primary drivers of monarch and other pollinator declines, with natural habitats being fragmented or converted for other uses and advancing agricultural technology eliminating milkweed from crop fields. Monarchs are also subject to predators, parasites, and diseases.

The history of monarch conservation

While gaining tremendous interest over the past few years, monarchs have captivated people for ages. A key milestone was the work of Fred and Nora Urquhart, Ken Brugger, Catalina Trail and volunteer citizen scientists in documenting the migration from the United States and Canada to the overwintering sites in Mexico in 1975. Since then, NGOs, researchers, federal agencies and individuals from across the monarch range have had a strong interest in the species. The charisma and popularity of monarchs have made them accessible as a research organism and an educational tool engaging scientists, educators, citizen scientists and the broader public.

In 2008, the Commission for Environmental Cooperation published the North American Monarch Conservation Plan. The monarch community gathered around this plan to strategize how to coordinate efforts and from this conversation, the Monarch Joint Venture (MJV) partnership was formed. 2014 brought another turning point driving the expansion of monarch conservation; the petition to the US Fish and Wildlife Service (USFWS) to consider listing monarchs under the Endangered Species Act (ESA) was issued and the record low population size ever recorded for the eastern population was reported.

Where are we now?

The 2014 ESA petition resulted in the USFWS conducting a 90-day finding to evaluate whether the claims in the petition warranted further assessment of the species. From 2015-2018, the Service has been conducting a Species Status Assessment to look in depth at all of the information available about the species current status and history in order to inform their final listing decision.

Another factor in the USFWS evaluation is consideration of what groups are doing to help. The Service will soon launch a Monarch Conservation Database to help track activities, both planned and existing. These activities will then be evaluated to determine whether species recovery is likely given the collective efforts of those planning or working on monarch conservation. Finally, USFWS is scheduled to make a listing decision by June of 2019.

A primary goal articulated by many involved in monarch conservation is to contribute voluntarily to monarch conservation at a magnitude that prevents the need for species listing and avoids possible regulatory outcomes.

What are our goals?

A goal set forth for the eastern population is to reach a population size of 6 hectares occupied at the overwintering sites in Mexico. 6 hectares is the size at which research suggests monarch populations would be able to endure severe events affecting the population (i.e. extreme weather). To accomplish this, it is projected that we need between 1.3 and 1.8 billion additional milkweed stems across the breeding range. For western monarchs, population targets are still in development.

How does science help us conserve monarchs?

In order to be effective in achieving this goal with limited conservation dollars and lands, it is essential to integrate science into our efforts. We understand the basics of what monarchs need, and that drives habitat conservation efforts forward at full momentum in the immediate term. However, integrating additional research and monitoring efforts into ongoing conservation is essential for our long-term strategy. The more information we have for the species and its habitats, the more effective our conservation efforts will be.

Citizen science has played an integral role in monarch conservation. Much of what we know about monarch biology and ecology is due to the contributions of citizen scientists.

A group of researchers in the U.S. that is tackling big questions and driving a number of publications is the Monarch Conservation Science Partnership (MCSP). A large effort by a subset of researchers in the MCSP is the development of a national monitoring strategy. The Integrated Monarch Monitoring Program goals are to build a robust data set that can help track monarch population status and trends across the U.S., as well as evaluating conservation practices to improve effectiveness. Program information will also update and improve models used to determine monarch population goals.

All Hands, All Lands

Recent research has illustrated the need for “All Hands on Deck”; meaning, in order to reach our conservation targets, we need everyone to be involved. Agricultural lands, Rights of Way, developed areas, public lands, and conservation lands all have a role to play.

Similarly, since monarchs occupy such a broad geographic range and have different needs during different stages of their yearly cycle, another publication shows that we can’t focus our conservation efforts in just one region. We need conservation efforts everywhere.

The many co-benefits to monarch conservation make it logical for partners of all kinds to engage! Honeybees, pheasants and quail, water quality, soil health, grassland song birds, farm income, sustainability, and more, all benefit from creating monarch and pollinator habitat. From all of these varying interests, habitat provides common ground.

All hands and all lands are needed to engage in monarch butterfly conservation.

How do we get there?

Coordination and planning is critical to get “all hands on deck” and succeed in reaching 6 hectares of overwintering monarchs. Partners across the country are coming together to protect monarchs and their habitat. By working together we can scale up our efforts to meet our goals.

The Monarch Conservation Implementation Plan identifies and prioritizes monarch conservation actions in the U.S. that will help restore the monarch butterfly population to a sustainable level. Anyone is encouraged to use this plan to identify and integrate priority actions into their existing or planned efforts. 

One of the main goals of coordination around monarch conservation is to make this issue more accessible. There are many ways to get involved. Coordinating efforts can provide a launching point into monarch conservation by having a central information clearinghouse to help direct those interested in what best fits their interests or skills.

Coordination takes place at many scales. The table below outlines examples of coordination efforts at scales ranging from tri-national to local.

Table showing examples of monarch coordination efforts at different scales.

MJV’s work at the national scale focuses on coordinating partners and other stakeholders, implementing conservation actions, and providing information. MJV partners are the boots on the ground that are driving monarch conservation forward. Coordination helps provide the framework and foundation for our partners to be a part of a national strategy to protect monarchs, and helps partners hit the ground running.

Together, we’ve built a solid foundation for pollinator conservation, now it is time to spread our wings and fly. Strengthening and expanding partnerships across disciplines during this unique moment in time is critical in scaling up monarch and pollinator conservation. 

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The Monarch Joint Venture is a national partnership of federal and state agencies, non-governmental organizations, and academic programs working together to conserve the monarch butterfly migration. The content in this article does not necessarily reflect the positions of all Monarch Joint Venture partners. Header photo by Wendy Caldwell at El Rosario in March 2018.

Correction: In the initial post, the western monarch population was stated to have been measured at 10 million butterflies in the 1980's. In fact, 10 million butterflies is an estimate made based upon data analysed via a Population Viability Analysis funded by USFWS and conducted by Washington State University in 2017. It is an extrapolation of available data, as opposed to a recorded measurement at the time. We apologize for this error!