Metropolitan Airpark Vernal Pool and Burrowing Owl Habitat Mitigation Project
-
Focus
Vernal pool and western burrowing owl habitat restoration
-
Location
Otay Mesa, San Diego County, CA
-
Habitat Types
Vernal pool and associated watersheds, maritime succulent scrub, coastal sage scrub, native grassland, and burrowing owl breeding and foraging habitat.
-
Implementation
Non-native biomass removal, upland and vernal pool seed collection and bulking, vernal pool and mima mound/berm creation (site grading), artificial burrowing owl burrow construction and installation, container plant and irrigation system installation, and hydro- and drill seeding.
-
Maintenance
Irrigation system operation, non-native species control, and as-needed remedial planting and seeding.
-
Monitoring
Drone surveys, protocol fairy shrimp surveys, hydrological monitoring, upland and vernal pool vegetation surveys, and burrowing owl habitat monitoring.
Over 60 acres of native habitat are being restored as mitigation for the development of the Metropolitan Airpark at Brown Field. The largest parcel of mitigation includes a 35-acre vernal pool and burrowing owl restoration site where RECON has created vernal pool basins, mima mounds, and berms for western burrowing owls. Within one month following installation, aerial drone surveys captured the vernal pools’ maximum extent of ponding. Drone surveys were conducted to document each pool’s ability to hold water for the required duration to support sensitive plant and animal species, which were introduced into the pools in winter 2023/2024.
The associated uplands and mima mounds outside of the vernal pools are being planted and seeded with species indicative of maritime succulent and coastal sage scrub habitats to blend with the native vegetation of the canyon edges found adjacent to the site. Within the berms, RECON installed artificial burrows where western burrowing owls have successfully nested and fledged just months after installation. The areas around the berms are being restored through the introduction of native grasses and low growing annual and perennial species to support owl foraging. Ongoing maintenance will continue to be conducted in a manner that gently shapes this previously degraded site into a viable and enduring habitat, capable of supporting a wide range of species.
