The Monarch Butterfly Story...

Photo Credit: Flickr/Creative Commons

Monarchs face many risks that are resulting in declining populations in both the eastern and western parts of their North American range. The largest impacts come from the loss of habitat for breeding, migrating, and overwintering. In addition, pesticides that are used to control insects and weeds have harmful unintended consequences for monarchs, a changing climate may be making some habitat less suitable and forcing changes in migratory patterns, and monarchs face many risks from natural enemies, such as predators, parasitoids, and diseases.

The loss of milkweed in agricultural fields is a major cause of decline in monarchs, though there are other factors contributing to the decline in milkweed availability. Herbicide application and increased mowing in roadside ditches and agricultural margins is eradicating milkweed habitat even more from rural areas.

If managed appropriately, roadsides could provide millions of acres of habitat suitable for monarchs and other pollinators.

These areas are often mowed or sprayed regularly throughout the growing season to control weedy species, but if transformed into a native plant community, they could require signficantly less maintenance once established while providing important habitat. If mowing is used to manage weedy species or invasives, it is best to do it during times when monarchs will be least affected by the disturbance. In addition, leaving sections of the habitat untouched will allow pollinators and other wildlife to find refuge in those areas while the disturbed portion of the site recovers.

Urban sprawl and continuing industrial development are also major factors influencing the decline in quality monarch habitat. Other anthropogenic factors, such as ozone pollution or increased carbon dioxide levels, can affect the health and distribution of milkweed plants.

Monarch Joint Venture: 2018 Monarch Conservation Implementation Plan

The 2018 Monarch Conservation Implementation Plan is designed to help facilitate cooperation and coordination in the United States to help accomplish our nation's goals for monarchs and other pollinators.

Photo Credit: USFWS

It identifies and prioritizes current important actions for monarch conservation in the U.S., and promotes cooperation between diverse organizations working together to achieve the goals outlined in the plan.

The plan was originally derived from the North American Monarch Conservation Plan (CEC, 2008), and is updated annually by the Monarch Joint Venture (MJV) partnership. As a national coordinating body, the MJV encourages the widespread use of this plan and will help identify opportunities for collaboration between different entities.

Recognizing that it will take an "all hands on deck" approach to reach our nation’s population and habitat targets, this plan was created in an effort to better coordinate monarch conservation in the U.S.

The plan is now available here and on the MJV website here. If you have any questions regarding the plan, please contact the MJV.

Monarch habitat Needs

Native Milkweed

Milkweed is an essential feature of quality monarch habitat. There are over 100 species of milkweed in North America, though monarch conservation organizations have prioritized species for each region of the U.S. The Monarch Joint Venture has produced a Milkweed Fact Sheet describing these priority species.

Photo Credit: Courtney Celley/USFWS

Many milkweed species are very hardy and grow in various landscapes. Common places to find milkweed include short and tall grass prairies, livestock pastures, agricultural margins, roadsides, wetland areas, sandy areas, and gardens. Though monarchs do use sites with very few milkweed plants, more plants can support more monarchs.

Fewer plants may result in higher per plant monarch density, which can increase the risk of spreading disease and can result in competition for food between larvae. Including native milkweed species in your monarch habitat is extremely important. Not only does native milkweed offer a food source for monarch larvae, but it provides nectar for a variety of other pollinators and also provides habitat for many other organisms.

Native plants are well adapted for the climatic conditions of their region and are easy to care for. Diversity in native plant communities supports many native insects and also provides a number of ecological benefits, such as erosion reduction and filtration.


Unlike larvae that rely only on milkweed to survive, adult monarchs use diverse nectar sources for food. Nectar plants are a key component to prime habitat for monarchs and other pollinators.

Spring blooming nectar plants (blooming approximately March 20 -- June 1) fuel the monarch migration northward from Mexico and inland from the California coast. Without abundant nectar sources through the migratory corridors, monarchs are less likely to survive and may not be able to reproduce successfully.

Summer blooming nectar sources (blooming approximately June 2 -- August 15) throughout the breeding range are vital to sustain a healthy breeding population.

Fall blooming nectar plants (blooming approximately August 16 -- October 30) are equally important; monarchs rely on abundant nectar sources in the fall to store enough energy not only to survive the long journey to their overwintering sites, but also to survive winter with very minimal nectar availability.

While non-native species can be used for nectar, native nectar plants are significantly more beneficial to an ecosystem. Native plants are well suited for the climatic conditions of an area and are responsible for important ecosystem functions, such as erosion control and filtration.

Surrounding area

The area surrounding a monarch habitat can influence monarch use of a site and survival. Land use changes have caused natural areas to be fragmented into smaller, more distant parcels of land disbursed throughout an ecosystem. Surrounding areas covered by natural vegetation are more beneficial to monarchs than surrounding land that has been altered by development or agriculture.

Natural vegetation surrounding any wildlife habitat reduces the risk of danger by human contact. Milkweed habitat mixed within human inhabited areas is important for monarch populations, but it can increase the risk of injury or death to monarchs by vehicles or human activity, such as pesticide use.

Monarch breeding habitats in close proximity to each other allow monarchs to find suitable habitat without traveling long distances.