Biological Monitoring

Our expert biologists provide wide-ranging biological services, including surveys, field studies, habitat assessments, and endangered species and vegetation monitoring.


Providing Wide-Ranging

Biological Services

SAWA’s Wildlife and Habitat Management Services biologists play an active role in restoring the watershed by performing field studies involving birds, bats, reptiles, amphibians, small mammals and plants. Our biologists also monitor animals and plants during removal of invasive species to protect wildlife from potential impacts during restoration. SAWA biologists are permitted local experts on the endangered Least Bell’s Vireo and Brown-headed Cowbird management. They document all known vireo territories and monitor the bird’s nests to help recovery efforts of this species. Though all of SAWA’s biologists are considered local experts on the Least Bell’s Vireo, they each have a variety of backgrounds and taxa specialties. The Wildlife and Habitat Management Services staff produce quality comprehensive reports for all projects.

SAWA biologists conduct various services, including endangered species monitoring and breeding.










In addition to monitoring vireo and supporting SAWA’s restoration activities, biologists monitor nests of the endangered California Least Tern Colony in Huntington Beach and conduct surveys for other threatened and endangered species, such as the California Gnatcatcher, Southwestern Willow Flycatcher, Coastal Cactus Wren, Stephens’ and San Bernardino Kangaroo Rat, and the Santa Ana Sucker.

Biologists also support community environmental activities by surveying sites before clean-ups and flagging sensitive areas. Local government agencies contact SAWA biologists when analyzing projects to get information on where endangered and sensitive species are located within the watershed.

Biological Monitoring,
Management & Reporting

SAWA biologists are graduates of accredited universities with bachelor’s or master’s degrees in Wildlife Biology, Zoology or closely related fields. They have more than 50 years of combined experience with Least Bell’s Vireo monitoring, Brown-headed Cowbird management and a variety of local flora and fauna studies.

The department consists of a manager, supervisor and six specially trained biologists. Our manager, supervisor and biologists are experts in Least Bell’s Vireo monitoring and Brown-headed Cowbird management. Each biologist works on various other plant and wildlife studies, some of which are listed in the Projects Section. SAWA also employs 7 to8 seasonal cowbird assistants during the vireo’s nesting season (March 15-July 31)


SAWA Biological Monitoring Staff


Melody Aimar

Biological Monitoring Programs Manager

Allyson Beckman

WHMS, Biologist Supervisor

Andrea Campanella

MSHCP, Biological Monitoring Program, Biologist Supervisor

SAWA Wildlife Habitat
Management Department Projects

SAWA is currently working on two wide-ranging projects. The first runs along Reach 9 of the Santa Ana River in Riverside and Orange County for the U.S. Army Corps of Engineers (USACE). The other is along Reach 3B in San Timoteo Canyon, within Riverside and San Bernardino Counties, for the USACE and USFWS. The following are the services included in these major projects: projects


This project includes Least Bell’s Vireo Monitoring, Brown-headed Cowbird Management and Agency Coordination


This project includes Least Bell’s Vireo Monitoring, Brown-headed Cowbird Management, Agency Coordination, Breeding and Wintering Bird Surveys, Herpetofauna Surveys, Raptor Surveys, Small Mammal Surveys and Nesting Bird Avoidance Monitoring.

SAWA WHMS Monitoring and
Management Services

In addition, SAWA’s Wildlife Habitat Management Department conducts a wide range of activities for numerous entities, including small mammal surveys, camera trap surveys, bat presence/absence surveys, baseline biodiversity inventories, nesting bird avoidance monitoring, and habitat assessment. Scroll down the page below for details on these services

Least Bell’s Vireo Monitoring

The Least Bell’s Vireo is a songbird that lives in Southern California creek-side habitats. These birds have come to California for hundreds of years to nest and raise their young.

In 1986, the Least Bell’s Vireo was listed as an endangered species. The main reason for this species’ population decline is the loss of habitat and nesting failure caused by the Brown-headed Cowbird. Biologists search all suitable riparian habitats in the Santa Ana River Watershed for vireo presence. In areas of dense vireo populations, pairs are monitored throughout the season to collect reproductive data and Brown-headed Cowbird traps are deployed where parasitism may occur. A detailed report is produced annually (see Publications).

Brown-headed Cowbird Management

The Brown-headed Cowbird is a brood parasite, which means it lays its eggs in another bird’s nest. Unfortunately, to the vireo and hundreds of other native bird species, when this occurs, the hosts’ young usually do not survive.

One female cowbird can lay up to 30 eggs in one season, equaling a potential loss of 120 native birds hatched yearly.  The cowbird has spread from the Great Plains states to the coast and is considered at epidemic proportions in Southern California. Biologists remove cowbird eggs and nestlings found in vireo nests. SAWA deploys up to 50 cowbird traps throughout the watershed in areas where vireos are known to nest and cowbird parasitism is expected. Traps are maintained from March through July near riparian habitats and local dairies during winter. SAWA offers cowbird trapping for mitigation requirements. A detailed report is produced annually (see Publications).

California Gnatcatcher Protocol Surveys

The California Gnatcatcher is a small songbird typically found in coastal sage scrub habitat that is a year-round resident in Southern California. This species was listed as threatened by the USFWS in 1993 and is considered a species of concern in California.

Like the vireo, this species is impacted by parasitism and benefits from SAWA’s cowbird trapping program. SAWA biologists conduct protocol surveys for this species for inventory purposes and to ensure upcoming or ongoing projects do not impact them.

Breeding/Wintering Bird Surveys

SAWA biologists conduct breeding and wintering bird surveys at multiple locations within the watershed. These surveys document changes in avian diversity and breeding activities in areas where habitat restoration or other habitat alterations (e.g., fire) may occur.

These surveys and area search and point count methods are also used for baseline inventory purposes. Results of breeding bird censuses are published in the Institute for Bird Populations by Point Blue and the Cornell Laboratory of Ornithology.

Certifications and Permits

SAWA’s WHMS manager, supervisor and biologists are listed on the following permits:

  • U.S. Fish and Wildlife
    Service, 10(a)(1)(A)
    Recovery Permit

Covered species: Santa Ana Sucker, Least Bell’s Vireo, Southwestern Willow Flycatcher, California Gnatcatcher, California Least Tern, Stephens’ Kangaroo Rat, San Bernardino Kangaroo Rat .

  • U.S. Fish and Wildlife Service, Migratory Birds – Salvage
  • U.S. Fish and Wildlife Service, Brown-headed Cowbird Trapping
  • California Department of Fish and Wildlife (Coastal) MOU

Covered species: California Least Tern, Cactus Wren.

  • California Department of Recreation-State Park
    • Scientific collection permit (entity)
  • California Department of Fish and Wildlife
    • Scientific collection permit (entity)

Department Clients

SAWA’s WHMS department collaborates with several agencies, districts and NGOs, including the U.S. Fish & Wildlife Service (USFWS), California Department of Fish and Wildlife (CDFW), U.S. Army Corps of Engineers (USACE), U. S. Forest Service (USFS), California State Parks, California Department of Water Resources (DWR) and the Regional Water Quality Control Board (RWQCB), as well as member and local agencies listed below:

San Bernardino Valley Municipal Water District (SBVMWD) Logo