Be a Community Scientist: Join the Western Monarch Count! | Cal Parks
Published: November 13, 2023
Lone monarch butterfly spotted at the Pismo Beach Monarch Butterfly Grove, Pismo State Beach | Photo courtesy of Yiming Chen.

It's that magical time of year again—western monarch butterflies are returning to California!   

Every year in the late fall, these brilliant flyers end their annual migration at special groves on the California coast, where they take shelter for the winter. These overwintering sites provide the specific microclimate that monarchs’ need to survive the season — including shelter from the cold, dappled sunlight, and ample nectar sources — before the butterflies disperse in the spring.  

Western monarch butterflies used to number in the millions. However, their population has plummeted in recent decades due to habitat loss, pesticide use, predators, disease, and increasing climate change. To track the health of the western monarch butterfly population, conservation organizations, scientists, and community members have been working together since the 1990s to count how many monarchs return to California every year. Known as the Western Monarch Count, this extraordinary effort helps inform and shape conservation projects.  

The Western Monarch Count 

2023 Western Monarch Count Dates:

Thanksgiving Count: November 11, through December 3 
New Years Count: December 23, through January 1 

Monarch butterfly clustering at Natural Bridges State Beach, Santa Cruz.

The yearly Western Monarch Count stretches from Mendocino to Northern Baja, Mexico, and includes two counting periods. The Thanksgiving Count — a three-week event centered around the holiday — is the height of this volunteer effort, followed by the shorter New Year’s Count at the end of the year.

The monarch population has drastically declined since the start of the Western Monarch Count in 1997 and less than 2,000 butterflies were counted in 2020. However, some good news has come in recent years. The western monarch population increased in 2021 and 2022, with more than 350,000 butterflies counted last year.  

The rebound in the western monarch population is promising, but continued monitoring is important to support conservation work and ensure monarchs’ long-term survival. To help with this crucial work, come be a part of this year’s 27th annual Western Monarch Count!

How Can I Participate?

The easiest way to get involved is to log your monarch sightings. To join the Western Monarch Count as a community scientist, check out their Step-by-Step Monitoring Guide here.

Step 1: Complete the Annual Volunteer Registration Form
Step 2: Connect with a Regional Coordinator
Step 3: Attend a Training (Online Training Videos & In-Person Training Events)
Step 4: Review Resources & Prepare Your Materials
Step 5: Monitor Your Site
Step 6: Submit Your Data
Step 7: Share Your Experience + Check Back for Updates 

Another way to record your monarch sightings is the community science application iNaturalist. All data you enter feeds into the Western Monarch Milkweed Mapper, a tool researchers use to map and better understand monarchs’ migration patterns and habitat locations.

Monarch sightings logged on iNaturalist at Lighthouse Field State Beach, Santa Cruz.

More Ways to Help Western Monarchs 

Joining the Western Monarch Count isn’t the only way you can help protect monarchs! This November, we will celebrate Giving Tuesday, a global day of giving and an opportunity for us all to think of others and give back to our community. With our focus on monarch and monarch habitat restoration, your gift will directly contribute to protecting the species! Plus, check out our other blogs on how you can help protect monarchs. 

Participating in the Western Monarch Count can be an inspiring experience that reminds us of California’s extraordinary beauty and the importance of preserving this iconic species. By visiting state parks, learning about monarchs, joining the count, and inspiring others to come along, you too can help protect these incredible creatures. Let's do our part to ensure that future generations can experience the wonder of the western monarch butterfly!

For more information on how to protect and preserve the western monarch butterfly, follow us on Instagram, Facebook, X/ Twitter, and LinkedIn.

Monarchs clustering at the Monarch Butterfly Grove at Pismo State Beach.