By Jeff Gaffney
Each fall and winter, one of the most fragile, recognizable, and endangered species, the western Monarch butterfly, makes its way to the tall eucalyptus trees around Moran Lake County Park. Fewer in number, with only hundreds remaining, they gather in the eucalyptus trees close to the Lode Street Sanitation facility, using the grove’s protection to rest and endure the colder season. These butterflies are not just a stunning seasonal sight; they are part of a vulnerable, shrinking population that requires secure, wind-shielded resting areas to finish their migration journey.
As caretakers of Moran Lake County Park, Santa Cruz County Parks has been collaborating with science-focused organizations such as the Xerces Society, agency partners, and local residents to ensure that we are maintaining both public safety and the butterflies’ overwintering habitat. In cooperation with the Santa Cruz County Sanitation District and a team of arborists, biologists, and entomologists, we are revising the Moran Lake Monarch Butterfly Habitat Management Plan, initially approved in 2010, to incorporate the most recent scientific findings and recommended practices from monarch conservation specialists, including the Xerces Society.
This revision goes beyond simply planting trees or eliminating dangers; it involves thoughtfully maintaining a fragile environmental system while addressing the practical demands of community security, climate resilience, and enduring sustainability.
Findings from the wind analysis
In reply to inquiries from the community that took place during our public meeting in July 2024, we initiated an extensive wind analysis earlier this year. This research, finalized in April 2025, examined how the existing tree cover shields the monarch cluster areas from wind, and how different approaches to tree management might impact the monarch butterfly population.
The results were promising, as we determined that it is safe to lower the height of eucalyptus trees in certain areas near the lake without affecting the monarchs’ overwintering habitat. Indeed, the research enabled us to locate particular groups of trees that could be pruned to decrease the chance of tree damage and enhance public safety without harming the fragile butterfly environment.
According to the results, County Parks proceeded with tree maintenance this summer in the North and South Moran Lakeside regions, along with finishing the removal of trees at the 40 Moran Way property. These locations were chosen due to their closeness to recent tree incidents, combined with advice from arborists.
This project was carried out by Lewis Tree Service as per a contract approved by the Board of Supervisors. As part of the rehabilitation plan for this region, we intend to plant indigenous trees there following the winter rainfall period.
Phased progress, long-term vision
Some community members have inquired about other sections of the park, including the Placer Street windbreak. A number of trees in that area were pruned by the Sanitation District in 2024, and further work is not part of this summer’s plan.
We are implementing a step-by-step strategy, focusing on regions that require attention according to scientific evidence, safety standards, and environmental considerations. Our ultimate objective is to slowly substitute non-native blue gum eucalyptus trees with indigenous species such as Monterey Cypress and White Alder over an extended period. These native trees benefit monarch butterflies, improve riparian ecosystems, encourage a wider range of plant and animal life, and are better suited for both the local community and the Monarch habitat.
In December 2024, we initiated this change; local volunteers assisted us in planting 64 indigenous trees in key areas designated for planting, with additional trees planned for the upcoming fall and winter seasons.
We take pride in the adaptive management strategies we have integrated into the care of Moran Lake County Park; we are committed to the meticulous, science-driven efforts that support the essential Monarch butterfly habitat, while collaborating with our active and dedicated community; we appreciate their continuous support and advocacy in shaping the park’s future, while safeguarding this unique and important natural asset.
Jeff Gaffney serves as the head of Santa Cruz County Parks.
