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

Bolsa Chica Lowlands Restoration Monitoring2007 Annual ReportThe location of each Belding’s Savannah sparrow territoryobserved was plotted on a map based on the behavior observedwhich included: singing by a perched male, scolding, carryingnesting material or food, feeding young, extended perchingtogether of mates, extended high and fully exposed perching ofindividuals, and territorial defensive behavior demonstrated bycircular chasing of birds from a territory. All behaviors weremarked on the field map of the zone being assessed. At thecompletion of the survey of each zone, the biologist reviewedthe notes, assessed the significance of each behavior noted, andwrote down a tally of the total number of territories assessed inthat zone. Biologists were careful to keep track of birds within azone to avoid over counting territories and did not spend toomuch time in a particular zone to avoid confusion. A figureshowing the highest ranking behavior observed to determine aterritory is presented in Appendix 1-E. For example, if theA territorial male Belding’s Savannah Sparrow.biologist mapped a male as perched for an extended period oftime, but it later began singing, the singing would supersede the perching in making the determinationand the final map would show a single singing male. The ranking of behavior for determining aterritory from most certain to least was: Extended perching of a pair, singing male, territory by chase,and extended exposed perching by a male. At the time of finalization of this document, follow-up fieldwork conducted during the 2008 breeding survey suggested that scolding or chipping were not areliable sign on definitive territories, and were subsequently removed from the enumeration ofterritories.From these breeding and territorial behaviors, the number and approximate locations of territorieswithin each zone were estimated. This method has been used by the U.S. Fish and Wildlife Serviceand California Department of Fish and Game when the scope of the surveys does not include precisedetermination of the number of territories present. This technique has been used for statewide surveys(Zembal et al., 2006). However, a clearly defined, written protocol for surveys of this type does notexist and there will therefore be some unavoidable variation in technique and judgment between surveyprograms.ResultsThe location of the territories estimated by the observed breeding and territorial behaviors is shown inFigure 1-10. A total of 351 territories were identified within the study site. Territories appeared to berelatively evenly dispersed throughout areas where pickleweed dominated salt marsh occurred. Usingarea of salt marsh available and the number of territories recorded within Zones 2-29, the averageterritory size was estimated to be 1,450 m 2 .The Future Full Tidal Basin supported the most territories, followed by the Muted Tidal Basins, thenSeasonal Ponds (Table 1-8). The number of territories did not correlate with the amount of salt marshavailable. The 2006-2007 rain season was notably dry, resulting the majority of the salt marsh areaincluded in the table below remaining dry during the nesting season.Merkel & Associates, Inc. 49