Marin Monarch Working Group
Western monarch butterflies used to be a common sight in Marin. But the number of monarchs in the county has declined by 99% since the 1980s.
Causes of this decline include climate change, habitat loss, natural predators, and pesticide use.
It’s not too late to act…but the time to act is now. Join the Marin Monarch Working Group to learn how you can help the monarch!
Who We Are
The Marin Monarch Working Group was established in 2019 to address the existential crisis facing the western monarch, one of California’s most iconic creatures.
We call on educators, biologists and botanists, gardeners and monarch lovers to join us and learn how to become involved in supporting the survival of the Western monarch butterfly.
Public Education and Advocacy
We disseminate science-based information about monarchs via our newsletter, website, social media, on-line meetings, and tabling at local events. We encourage and guide local residents’ outreach to local and state officials about policies and practices for helping monarchs.
Community Science
Community science draws upon data collected by community members trained to observe and create a record of their observations. We connect local monarch lovers with training and monitoring opportunities led by MMWG co-founder, Mia Monroe.
Habitat Restoration
We take on projects to create and restore monarch habitats in private and public spaces. And we work with other groups engaging in this important work.
Updates from the MMWG!
Sign up for a Butterfly ID Clinic…
11 AM on Saturday June 13
MMWG is sponsoring a butterfly identification clinic. Take it for fun or use it to brush up your ID skills if you plan on participating in one or both of the local butterfly counts happening this summer (see box below).
The event will take place at the Marin Art and Garden Center, 30 Sir Francis Drake Blvd. in Ross. The instructor is longtime butterfly enthusiast and count leader Wendy Dreskin. We will hear from Wendy and look around for butterflies in the extensive MAGC garden.
Bring your lunch and join us at MAGC. A $10 donation is suggested for non-students. Please bring cash or donate using this link: https://secure.everyaction.com/fAOB1TlsLkuahhdaz5UcvQ2
Please RSVP at marinmonarchwg@gmail.com and we will respond with specifics about where to meet Wendy and the group.
AND….Take Part in the 2026 Butterfly Counts in Marin
The North American Butterfly Association has run the Butterfly Count Program since 1993. Each of the 450 annual counts consists of a compilation of all butterflies observed at sites with a 15-mile diameter count circle in a one-day period. Comparisons of the results across years is used to monitor change in butterfly populations and study the effects on them of habitat loss, climate change, and pesticides.
The NABA dataset was a primary source of information for the influential study published in 2025 in the journal Science: Rapid Butterfly Declines across the United States during the 21st Century.
In Marin there are two butterfly counts. You can take part in either one whether or not you have attended an ID clinic.
Central Marin Butterfly Count on Sunday June 21st. To participate contact Wendy Dreskin at wendydreskin@gmail.com
Point Reyes Butterfly Count on Saturday July 18th. To participate contact Ed Nute at pointreyesbutterflycount@gmail.com
We are advised to “leave the leaves” on the ground in the fall. What should we do with them in the spring?
Many Marin gardeners allow fallen leaves to remain on the ground throughout the winter. During that time, the leaves gradually decompose, forming mulch that retains moisture in the soil and provides nutrients for plants. Importantly, leaf litter also offers shelter for ground-nesting bees, moths, beetles, lacewings, and other beneficial insects. And allowing leaf litter to decompose naturally helps rebuild soil health.
But what about when spring arrives? As spring flowers emerge in your garden, you may feel tempted to create a cleaner look by removing the remaining leaf litter, possibly replacing it with purchased mulch.
The dilemma: While newly applied mulch may look tidy and will indeed benefit the plants, its application may destroy the habitat of insects hidden among the decomposing leaves.
Here are three general options to consider:
If you decide to remove leaf litter, wait until the weather is relatively warm (i.e., daytime temperatures above 55-60 degrees). In Marin, this is usually in late March to mid April inland, and somewhat later along the coast. By this time fewer insects will need this habitat.
If you really do not like the look of leaf litter, consider adding a thin layer of purchased mulch over it. This will likely preserve some of the insect habitat while affording a more uniform backdrop for your plants. And the new mulch will also contribute to soil health.
Try a mix of approaches in your yard. For instance, you might consider leaving the leaf litter untouched under trees and shrubs, or in fenced-in or less visible areas. In publicly visible areas or in those where the plants are young and small, you can add a a thin layer of mulch on top of the leaf litter.
One last thought: If you leave leaf litter on some or all of your yard, you can post a yard sign from the Xerces Society that explains your reason for keeping the leaves.
Note: Monarch butterflies are not part of this picture — they are overwintering in tall trees along the coast and have no need of a leaf-litter habitat!
To some gardeners, the small plants in this winter garden may seem overwhelmed by the abundant leaf litter and magnolia petals. To others, it is a pleasing palette that will continue to improve as the growing plants take up more space (photos: Susan Holloway)
How to Design Fire-wise Gardens for Pollinators
County officials are encouraging property owners to make sure their landscaping will not provide fuel for flames. Do some of these suggestions run counter to recommendations for creating a thriving native plant garden for pollinators? Yes, to an extent, but there are workarounds that can satisfy both goals.
First, pick the right plants. Many types of native trees and pollinator plants are fire resistant. If you are selecting new plants, this list of fire-resistant and fire-prone plants can be very helpful. In general, less fire-prone plants have leaves that are high in moisture, contain less wax, oil, and resin, and have an open structure.
Second, pick the right mulch. Native plant gardeners have typically been advised to allow organic matter to remain on the surface of the soil in order to accommodate plant self-seeding and to provide habitat for insects and other creatures.
Current fire-safe advice is less supportive of leaf litter, specifying the removal of dry, woody vegetation including clumps of fallen leaves and pine needles. One option is to remove the leaf litter near your home, but allow some of it to remain in a portion of your garden.
Fire-safe advocates typically acknowledge the role of organic mulch in conserving soil moisture, impeding the grown of weeds, and adding organic matter as it breaks down. However, fire-safe versions commonly recommend that gardeners use nonorganic mulch such as rocks and gravel in the five foot zone surrounding homes. In the area beyond the five foot zone, it is better to use composited wood chips — rather than fine, stringy mulch.
To obtain detailed information on these topics, consult these helpful guides by Fire Safe Marin and the Marin Master Gardeners.
Join our mailing list
Everyone on the mailing list receives our monthly newsletter and an email invitation to attend our regular MMWG zoom meetings, where we share information on the status of the monarchs and plan actions to safeguard their welfare.
Please consider making a donation
Everyone associated with MMWG activities works on a volunteer basis, but we welcome donations to support our projects. Donated funds are used to cover purchases like plants for restoration projects and materials for the production of our handouts.
If you would like to contribute to MMWG, please write a check to the Marin Monarch Working Group and send it to the following address:
MMWG (c/o TIRN) PO Box 370 Forest Knolls, CA. 94933
Comments Welcome!
Please send comments and suggestions about this website to Susan Holloway at susandholloway@gmail.com