California Department of Transportation

Effects of Construction Activities on Valley Elderberry Longhorn Beetle Habitat

The Valley Elderberry Longhorn Beetle is a species whose biology is poorly understood and for which the impacts of management activities need to be mitigated under the Federal Endangered Species Act. Current mitigation practices are based on the small amount of ecological information available about the species and Caltrans has spent a considerable amount of money on mitigation.

Transportation activities including construction lead to three types of potential impacts on the beetle:

  1. Dust from construction sites may influence both the beetle and its sole host plant, the elderberry.
  2. Noise and vibration from both construction sites and highways might impact the beetle.
  3. Highway maintenance activities may necessitate pruning of elderberry shrubs.

Each of these is being studied by using manipulative experiments and observational studies that compare potentially impacted and non-impacted areas. The investigations will allow more accurate assessment of the effects of both highways and construction on the Valley Elderberry Longhorn Beetle and will be used to improve estimates of incidental take and mitigation requirements.

Valley Elderberry Longhorn Beetle Habitat
Valley Elderberry Longhorn Beetle Habitat