The santa ANA watershed is the largest coastal river system in southern california

The santa ANA watershed association (sawa) is committed to the protection and improvement of natural areas within the watershed with major focus on the removal of invasive species, native habitat enhancement, and the monitoring and protection of endangered, threatened, and other sensitive species. The watershed includes a diversity of terrain including mountains, foothills, valleys, and the coastal plain. The main river is the santa ANA river, which contains more than 50 tributaries. Study sites contain typical southern california riparian vegetation including tall canopies of fremont cottonwood (populus fremontii) and gooddings black willow (salix gooddingii), sub-stories of arroyo and red willow (salix lasiolepis and salix laevigata, respectively), and mulefat (baccharis salicifolia). Since 2000, populations of endangered least bells vireo (vireo bellii pusillus hereafter vireo) have been monitored and managed during the breeding season. Data are collected on status, distribution, breeding chronology, reproductive success, and nest site characteristics. Other data collected includes spatial data on all sensitive species observed during vireo surveys and a list of all species detected at closely monitored sites. Additionally, brown-headed cowbird (molothrus ater hereafter cowbird) trapping is conducted concurrently in or near riparian habitat as well as during the fall and winter at local dairies. A detailed report and shape files with a complete attribute table and detailed metadata is produced annually and submitted to the USACE, wildlife agencies (USFWS, california department of fish and wildlife, USGS) and local stakeholders. Since 2015, this monitoring and cowbird control supports the santa ANA river main stem (sarm) project, which is designed to provide flood risk reduction to growing communities in orange, riverside, and SAN bernardino counties, extends approximately 75 miles along the santa ANA river from the upper canyon in the SAN bernardino mountainsdownstream to its confluence with the pacific ocean at newport beach, orange county, california. The sarm project is designed to provide various levels of flood protection ranging for areas most susceptible to damages from flood flows. Once completed, the project will afford increased flood protection for millions of residents and businesses and prevent estimated damages of nearly $15 billion from future flooding. Biological opinions (BO), in particular the 2001 BO (REF: FWS-SB-909.6) require monitoring of the least bell s vireo (vireo bellii pusillus) (vireo) in the year prior to construction and also during construction, as well as brown-headed cowbird (molothrus ater) (cowbird) trapping. This requirement was reiterated and expanded in the 2015 BO (REF: fwsor-08B0408-15F0592) and 2021 (FWS-wriv-08B0408-20F1132). The U.S. Army corps of engineers (corps) recognizes the importance of data collected during past vireo monitoring and cowbird trapping efforts by entities including, but not limited to, the santa ANA watershed association (sawa), the orange county water district (ocwd), and USACE survey have provided managers and regulators the ability to make informed decisions regarding management efforts and tactics to successfully manage the recovery of this species while implementing necessary and vital projects in the interest of public safety. This work is a continuation of surveysand trapping efforts conducted by the USFWS through sawa (on behalf of USACE) during the 2015 - 2023 nesting seasons. This scope of work expands these services to include the 2024 to 2028 nesting season, as well as a limited year-round cowbird trapping effort that will be concluded in march april 2029