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

Bolsa Chica Lowlands Restoration Monitoring2007 Annual ReportI. ECOLOGICAL MONITORING PROGRAMThe ecological monitoring stations were established using direction provided in the Bolsa ChicaLowland Restoration Project Biological Monitoring and Follow-up Plan, as well as observations madein the field at the time of station determination. Figure 1-1 presents the general sampling locations forwater quality, benthic infauna, fish, and birds. Appendix 1-A summarizes the dates of each field event.Within each of the following sections, more detailed maps of sampling locations are presented asneeded.1.1. WATER QUALITY MONITORINGThe development of new habitats in the FTB and MTBs after construction will be influenced by manyfactors, including water quality. Quarterly monitoring has been designed to document both the waterquality conditions at the time of biological monitoring events, as well as longer-term conditionsthrough the use of untended, deployed instruments that collect continuous data. The Monitoring Plancalls for water quality monitoring to be initiated in Year 2 of the monitoring. Therefore, monitoringwas only conducted during October 2007 (first quarter of Year 2).MethodologyDuring 2007, water quality data were collected in the FTB only, as the MTBs were not yet open totidal influence. Hydrolab Datasonde 5 water quality instruments were deployed at two stations withinthe FTB: Station 1 and Station 2 (Figure 1-1). The station coordinates are provided in Appendix 1-B.These locations were positioned to correspond to the general location of fisheries and benthicinvertebrate monitoring. The units were calibrated in accordance with manufacturer specifications andprogrammed to log water depth (m), temperature (C), dissolved oxygen (DO)(mg/L), turbidity (NTU),and salinity (ppt) at 20-minute intervals. The units were mounted to weighted boards and deployed inthe FTB from October 10 to November 10, 2007. The depths at water quality Stations 1 and 2 areapproximately –1.2m and –1.3m NAVD88, respectively.Following data collection, the retrieved units were placed in calibration solutions and re-checked foraccuracy. A technician downloaded the units and transferred the data to the project database forreview and analysis. The data were reviewed to detect and remove spurious data points that may haveresulted from algal fouling of probes, signal decay from sediment loading or biotic activities, or thatwere out of the range of the capability of the unit. Accepted data were plotted graphically, numericallyanalyzed, and reviewed to generate summary statistics.ResultsWhen the units were retrieved from both stations, it was noted that invertebrates and fish had heavilycolonized them. Both units were occupied by two-spot octopus (Octopus bimaculoides) and juvenilekelp bass (Paralabrax clathratus). As anticipated, the collected data reflected the interference thatoften results from intermittent animal activity around the sensor probes. Particularly affected were twooptically detected parameters: dissolved oxygen at Station 2 and turbidity at both stations. Additionalwater quality data collected with a tended unit during fish sampling was used to understand theconditions during periods of data loss from the untended units.Merkel & Associates, Inc. 14