2007 Annual Monitoring Report (pdf 16MB) - Bolsa Chica Lowlands ...

Bolsa Chica Lowlands Restoration Monitoring2007 Annual Report1.6. AVIAN MONITORINGGeneral Avian MonitoringIntroductionThe general avian monitoring program for the Bolsa Chica Lowlands Restoration Project was designedto employ similar methodologies and survey units as those used in previous pre-restoration biologicalsurvey work. The Monitoring Plan calls for avian monitoring to be conducted once per month inmonitoring Year 2, with no monitoring in Years 1 and 3. Review of other long-term avian monitoringprogram data, such as the Batiquitos Lagoon Restoration Long-Term Monitoring Program and the Portof Los Angeles/Port of Long Beach Biological Baseline Study, suggested that such closely spacedmonitoring events do not provide significantly more useful information on avian site-usage thanquarterly or bi-monthly surveys do.With review and concurrence by the Bolsa Chica Steering Committee and the California CoastalCommission, a revised monitoring schedule was adopted to conduct the surveys every other month,distributed over a period of two years (monitoring Year 2 and 3), for the same total of 12 surveys. Thisapproach is more likely to detect annual anomalies, capture natural inter-annual variations in avianusage, and better document changes in distribution and site use patterns as the restored site matures.Additionally, it was originally anticipated that by Year 2 the muted tidal basins would be receivingtidal waters. Due to delays in opening the basins to tidal influence, the relictual salt marsh in thebasins had not had a chance to develop significant infaunal communities that would support the arrivalof migratory shorebirds. Extending the avian monitoring over both Years 2 and 3 will allow for thetracking of avian usage both before and after the introduction of tidal influence to these basins, andpresumably the development of conditions attractive to migratory birds. It is anticipated that the basinswill be opened to tidal influence in 2008.Merkel & Associates biologists conducted the avian surveys with assistance from a team of birdersfrom Chambers Group, Inc.MethodologyStudy AreaThe study site at Bolsa Chica was divided into "zones" (differing from "stations" for the fish andbenthic studies) for the general avian surveys (Figure 1-7). U.S. Fish and Wildlife Service providedthe initial zone boundaries and numbering. The term zone is interchangeable with the term cell, oftenused at Bolsa Chica when numbering the marsh units bounded by service roads throughout the site.The newly created Full Tidal Basin (FTB) was divided up into new zones as described below.The Seasonal Ponds at the southeastern side of Bolsa Chica are divided into Zones 2 through 13.These zones consist mainly of salt panne with small to extensive expanses of pickleweed, primarilyalong the slightly elevated zone boundaries. Portions are seasonally inundated with fresh to brackishwater. Zones 14 through 40 and Zone 63 (Future Full Tidal Basin) occur between the Seasonal Pondsand the Muted Tidal Basin and include Freeman Creek. These zones are very similar to the SeasonalPonds and consist mainly of salt panne and pickleweed, although there are some areas that retain wateryear-round. Zone 36 is primarily a freshwater marsh. Zones 41 through 50 and Zone 66 (Muted TidalMerkel & Associates, Inc. 35