Biologists have attached tiny trackers to five of Goleta’s beloved monarch butterflies to track behavior, for the first time ever along the Central Coast. 

One of the biologists attaching the tracking devices is Charis Van der Heide, a consulting biologist for the City of Goleta with Althouse and Meade Inc. 

“It’s incredible to be on the forefront of breaking research,” she said.

The data gathered can inform conservation efforts. The tracking device also allows people to see butterfly activity themselves through the app, Project Monarch Science.

On tagging days, biologists arrive at Ellwood Mesa at dawn to capture the butterflies, using early morning temperatures to their advantage. Butterflies can’t fly when it’s 55 degrees or colder, according to Van der Heide.

“They do these very clever zigs and zags, and it’s quite tricky to run after them with a butterfly net,” she said. 

At cold temperatures, the butterflies fall into the net, allowing biologists to bring them to a tagging station, where they inspect wing health and ensure that the butterflies weigh more than 0.5 grams, enough fat to hold the device. 

The butterflies are then laid out with weights on their wings to give biologists a clear view of the body using tweezers to adhere the small tracking device with eyelash glue, easily found at any beauty or retail store.

Van der Heide compares the weight of the tracker on the butterfly like a person carrying a 20-pound backpack. The tracker is made up of an antenna and a small square solar panel, small enough to fit in the palm of a hand and on the butterfly’s body.

The whole thing is equivalent to the weight of a grain of rice, according to her.

Even with the extra weight, the butterflies seem to fly normally, according to Van der Heide.

After the 20-minute tagging process, the butterflies are released from where they were taken. 

Jade and Rob Thiel, Washington D.C. tourists visiting the Ellwood Mesa on Monday, were astonished when Van der Heide showed them the trackers.

The research is partially funded through a grant from the U.S. Fish and Wildlife Service under the Coastal Program, according to Van der Heide. Ellwood Friends also purchased additional tags for the research. Through the two avenues of funding, 40 of the $200 tags were purchased.

The tiny but expensive tags also need a small data plan to collect data via a Bluetooth connection. 

“Our butterflies have cell plans, and we are paying for it,” Van der Heide joked.

The City of Goleta set up a motus tower, which is a radio tower with an antenna that tracks the movements of the tags on top of the Bluetooth tracking.

She said she hopes the trackers will give insight into the butterflies’ movements and noted that one of the butterflies, Danny, named after her career mentor, has only stayed close to one spot at Ellwood.

“I expected there to be more movement between this site to the north of us and the Ellwood Main,” she said. 

Before this research, despite the monarch butterfly being one of the most recognizable insects, biologists did not know much about its movements.

“What I am really interested to learn is if there is one place that the butterflies go for nectar,” Van der Heide said. “Then we can know where we should be planting more nectar plants.” 

The monarch butterfly has been historically dwindling in numbers, according to the U.S. Fish and Wildlife Service. Only four were counted at the Ellwood Main Butterfly Grove in 2024. 

Some of the primary threats to the population include loss of milkweed habitat for breeding because of herbicide-resistant crops, pesticide use, climate change, logging and development, according to the Xerces Society for Invertebrate Conservation.

In 2024, the butterfly also was proposed to be included in the Endangered Species Act to halt possible extinction.

The 2025 season is seeing similar low numbers so far as monarch butterflies migrate to Goleta beginning in October through February, known as overwintering. The population usually peaks in mid-December. 

Biologists go out into Ellwood Mesa biweekly throughout the overwintering season to count the population. 

Part of conservation efforts in the Ellwood Mesa include planting eucalyptus trees to make up for 25% of the trees that dried out in 2017 following a long-term drought. 

“This technology is able to inform our restoration efforts over the coming years as these trees grow in. We’ll see the response from the monarchs and how they use the site,” said George Thomspon, Goleta’s open space manager. 

He added that the information gathered has the potential to influence future city policies regarding the butterflies. 

While Van der Heide wrapped up tagging by Friday, she hopes more tagging can be done in the spring to potentially track movement out from the overwintering sites. 

Community members also have the chance to name a butterfly fluttering in Ellwood Mesa. However, it comes with a cost — $1,000 exactly. The first 20 donations to Ellwood Friends will receive the opportunity. As of Tuesday, only two people had donated. 

People are able to donate other amounts to Ellwood Friends as well. 

The city updates the public on current monarch counts, and Thomson believes the main takeaways from the collected data might be published there. However, it is too early into the research process to know when it might be available. 

People can visit the butterfly grove for free and can park at the Ellwood Mesa Open Space & Sperling Preserve at 7729 Hollister Ave. After parking, a half-mile walk will get people to the grove. Click here for a map.