American badger and burrowing owl photos.

We know that American badgers, a species of special concern in California, live in the grasslands of many Midpen preserves and that the burrows they make are often used as winter homes for burrowing owls. But what we don’t know is how large their population is, where they are located and where they travel (identifying wildlife corridors and habitat fragmentation). This information will help us make science-based decisions to manage our grasslands and coordinate with other landowners so these animals can survive and thrive. To make this happen, Midpen is conducting a three-year badger and burrowing owl habitat study, which began in 2019.

Badger ©Chris Fielding/Santa Clara County ParksAmerican Badger
(Taxidea taxus, fossorial carnivore)
California species of special concern

  • Elongated black head with distinctive white stripes
  • Small ears, short legs and flattened gray body
  • Nocturnal and solitary; shelter in underground burrows
  • Large foreclaws adapted for digging (main diet is burrowing rodents)
  • Burrows have a distinctive soil mound on one side only and claw marks on the sides
  • Roam and hunt large home ranges (1,000+ acres), sleeping in burrows along the way

Burrowing owl ©Carlos Henrique Luz Nunes de AlmeidaBurrowing Owl
(Athene cunicularia)
California species of special concern

  • Small, long-legged
  • Yellow eyes and bill, rounded head, no ear tufts
  • Mottled brown and white feathers
  • Active during the day
  • Stand on the ground or low fences
  • Jerk up and down when alarmed
  • Eat insects and small animals
  • Shelter in burrows often made by other animals, like badgers

Badger at Windy Hill captured via Midpen wildlife camera during this study.

Research Goals and Techniques

The goal of our research is to gain additional expertise in the management of grasslands for American badgers and burrowing owls, which will also benefit other related species, by:

  • Creating a detailed habitat suitability assessment for these animals that includes Midpen preserves and neighboring lands, as much as possible.
  • Determining the presence, use and status of these species within the available habitat.
  • Recommending specific management measures to protect and enhance this habitat.

The research techniques are being used in this study include:

  • Computer mapping and habitat linkage analysis
  • Field transect surveys and visual monitoring
  • Wildlife camera monitoring
  • Banding and telemetry to determine breeding locations (owls)
  • Genetic analysis of hair (badgers) and fecal samples (badgers and owls)

This study is being conducted for Midpen by Pathways for Wildlife and the San Francisco Bay Bird Observatory.

Badger ©Mike Bolte

Volunteer

Volunteers are needed to help with transect survey field research that involves walking a 1-km transect to assist with the search for and recording of badger burrows (or burrowing owls) and to help take vegetation measurements. Research will be done separately for each species.

  • If you are interested in being a badger volunteer, please contact Tanya Diamond, wildlife ecologist at Pathways for Wildlife, at tanya@pfwildlife.com.
  • If you are interested in being a burrowing owl volunteer, please contact Dan Wenny, landbird biologist with San Francisco Bay Bird Observatory, at dwenny@sfbbo.org.

Burrowing owl ©Lesley Hamamoto

Report Sightings

If you see a badger or burrowing owl in our region, alive or dead, we want to hear from you so that we have as much data as possible for analysis. Please email Tanya Diamond (tanya@pfwildlife.com) with sighting details. This information will be added to our database to inform the study. For badger roadkill, we may be able to follow up to retrieve hair samples for genetic testing.