San Diego Management & Monitoring Program


Vertebrate Species
Northern Harrier (Circus cyaneus) Surveys

in progress

Project description

Northern harrier is a species that has disappeared as a breeding resident from many areas in southern California. Once abundant and widespread in San Diego County, there are few known breeding populations remaining in marshes and grasslands on Conserved Lands. In 2021, AECOM surveyed for northern harriers at historic and recently documented breeding sites and in other suitable habitat to determine if harriers are present during the breeding season, and to estimate population size and breeding status. AECOM used an SDMMP protocol to evaluate habitat quality and threats at each suitable habitat site, even those without northern harriers. SDMMP will use these data, and data from subsequent surveys, for the development of management priorities.


Project protocol

Name: San Diego County 2021 Northern Harrier Surveys: Breeding Surveys and Habitat and Threat Assessments

Description: This survey protocol outlines the methods for conducting NOHA surveys across San Diego County between April and July, 2021.


Project Data - Files


Project focus

Project type: Monitoring

Target species: Northern harrier

Data steward: Emily Perkins

Main implementing entity: San Diego Management and Monitoring Program

Partner: AECOM

Point of contact: Loren Merrill

Project Page manager: Sarah McCutcheon

SDMMP lead: Kris Preston

Study lead: Andrew Fisher; Loren Merrill


Project Funding

San Diego Association of Governments

Files and Documents