Two species of newts can commonly be found in Midpen preserves: California newt (Taricha torosa) and rough-skinned newt (Taricha granulosa). Both are similar in appearance — the California newt has orange skin around the bottom of its eye while the rough-skinned newt has gray skin at the bottom its eye. The California newt also has eyes that protrude beyond the edge of the jaw line when viewed from above, while the eyes of the rough-skinned do not protrude.
Midpen is partnering with Peninsula Open Space Trust and other agencies to conduct a newt population and mortality study to estimate the number of newts attempting to travel to and from Lexington Reservoir across Alma Bridge Road and the percentage that are killed by vehicles during a single breeding season. The study will build upon several years of community science data collected and all data will be analyzed to quantify impacts on the local newt population. Although Midpen does not own or operate Alma Bridge Road, we are committed to working with regional partners to implement solutions.
We are grateful for the volunteers and newt advocacy groups who brought this issue to our attention and who worked diligently to document over 11,000 newt deaths since 2017.
The proposed study will build upon existing community science data and help all parties to better understand:
- size of the breeding adult newt population
- the proportion of newts crossing Alma Bridge Road to and from Lexington Reservoir
- the percentage killed by vehicles during a single breeding season
- carrying capacity of Lexington Reservoir
Participating organizations include:
- Peninsula Open Space Trust
- California Department of Fish and Wildlife
- Santa Clara County Roads
- Santa Clara County Parks
- Valley Water
- United States Geological Service
Additional information can be found below in the report and presentation from the September 23 Board of Directors Meeting.
November through March is migration and breeding season for the California newt, a native salamander species. Newts make their way from sheltered upland areas to ponds, lakes, creeks and other wet areas to breed. Once in the water, they become aquatic and can swim.
Newts migrate in a mass and can be seen in large groups crossing Midpen trails and local roadways, especially in rain and heavy fog. Trail users are asked to proceed slowly and keep an eye out for newts. Areas of known newt migrations in and near Midpen preserves include:
- Los Gatos Creek/Lexington Reservoir including the Jones trail, Los Gatos Creek Trail, Alma Bridge, Montevina and Black roads
- Mindego Hill Trail from Alpine Road to the council circle
- Alpine Road near the Ancient Oaks Trail
- Mt. Umunhum Road
If I see migrating newts on the trail, what should I do?
- Do not remove newts. They do not make good pets and they secrete a powerful neurotoxin through their skin to repel predators. This poison can cause death in many animals, including humans, if ingested.
- Do not handle local newts, instead pass slowly and alert other trail users. Although some newts are not able to successfully cross a road or trail, many do make it as evidenced by the ongoing migrations seen each year.
- Report newt observations using community science, like iNaturalist, which Midpen uses along with other sources to determine where migrations occur and to identify areas of conflict where dead newts are observed.
Migrating Newts at La Honda Creek Open Space Preserve