On Sunday, May 12, 2013, ESPchris woke up and started sampling at noon. After processing the sample, at 4:00pm it reported its first positive signal of the 2013 bloom season for Alexandrium fundyense. Based on lab calibrations from known concentrations using cultured cells, the field concentration was calculated to be in the 50-100 cells/Liter range, just above our detection limit. No other probes on the array showed a positive signal.
Just a brief time ago on its Monday noon sampling, ESPchris woke up again to do his job...and reported another positive signal in the same range as Sunday's sample...two days in a row with weak positive signals.
Note that the ESP sample intake is at about 1.5 meters, just below the surface buoy, so all reports are from that depth. The sample is delivered through the hollow stretch to the ESP at 20m for processing...that configuration insulates the sensitive ESP from heavy wave action. A Seabird CTD (with fluorescence sensor) and a SUNA nitrate analyzer are located near the intake. The CTD data is reported in near real time, while the SUNA data is recorded internally and will not be available until recovery of the mooring. Dr. Dave Townsend and Maura Thomas are an integral part of the ESP team. They have been calibrating the SUNA instrument at the bench and collecting nutrient samples right along with the Alexandrium and Pseudo-nitzschia samples. Next year, we expect to integrate the SUNA data stream into the near real time ESP data stream through the new electronics architecture...so that improvement is coming.
We are currently mobilizing to sample near the mooring. The R/V Tioga left the dock today and will be on site Tuesday morning through Thursday to collect samples alongside ESPchris, if the weather permits.
We're thrilled that ESPchris is doing its job as planned and will report back the ground truth findings at the end of the week.