WHOTS Mooring Subsurface Instrumentation

Transcription

1 UH Contributions to WHOTS-15 Cruise Report by Fernando Santiago-Mandujano, Jefrey Snyder, Svetlana Natarov, Kelsey Maloney, Noah Howins, Garrett Hebert, and Roger Lukas WHOTS Mooring Subsurface Instrumentation 1. WHOTS-15 Deployment For the 15 th WHOTS mooring deployment that took place on 22 September 2018, UH provided 17 SBE-37 MicroCATs and two RDI Workhorse ADCPs (300 khz and 600 khz). Sea- Bird (David Murphy) provided three experimental SBE-37SMP MicroCATs. In addition to the instrumentation on the buoy, WHOI provided two Vector Measuring Current Meters (VMCM), two deep MicroCATs (SBE-37) and all required subsurface mooring hardware. The MicroCATs all measure temperature and conductivity, with 11 also measuring pressure. All MicroCATs were deployed with antifoulant capsules. In addition, a 69 khz Vemco acoustic receiver was included in the mooring to detect the presence of sharks that have been tagged with acoustic transmitters (see Appendix D). Information about these instruments, including location on the mooring, is given in Table 1. Before deployment, a bag of ice was placed in contact with each MicroCAT s temperature sensor, except for the WHOI MicroCATs, to produce a spike in the data as a reference point to check the instrument clocks. The WHOI MicroCATs were submerged in a fresh cold water bath to produce the spike in the data. 1

2 Table 1. WHOTS-15 mooring subsurface instrument deployment information. All times are in UTC (MM/DD/YY hh:mm:ss) SN Instrument Depth (m) Pressure SN Sample Interval (sec) Start Logging Data Cold Spike Begin Cold Spike End Time in Water 6892 MicroCAT /18/18 00:00:00 9/21/18 22:15:00 9/21/18 22:45:00 9/22/18 19:28: VMCM 10 N/A 60 9/17/18 03:20:00 9/22/18 18:57:00* 60 9/17/18 9/22/18 19:10: MicroCAT 15 N/A 180 9/18/18 0:00:00 9/21/18 22:15:00 9/21/18 22:45:00 9/22/18 19:02: Vemco 69Hz Receiver 25 N/A N/A 9/19/18 0:00:00 N/A N/A N/A N/A 9/22/18 18:53: MicroCAT 25 N/A 180 9/18/18 0:00:00 9/21/18 22:15:00 9/21/18 22:45:00 9/22/18 18:53: VMCM 30 N/A 60 9/22/18 02:00:00 9/22/18 18:43:00* N/A N/A 9/22/18 18:52: MicroCAT 35 N/A 180 9/18/18 0:00:00 9/21/18 22:15:00 9/21/18 22:45:00 9/22/18 18:48: MicroCAT 40 N/A 180 9/18/18 0:00:00 9/21/18 22:15:00 9/21/18 22:45:00 9/22/18 18:42: MicroCAT /18/18 0:00:00 9/21/18 22:15:00 9/21/18 22:45:00 9/22/18 18:37: khz ADCP 47.5 N/A 600 9/22/18 00:00:00 N/A See Table 2 N/A See Table 2 9/22/18 19:45: MicroCAT 50 N/A 180 9/18/18 0:00:00 9/21/18 22:15:00 9/21/18 22:45:00 9/22/18 19:47: MicroCAT 55 N/A 180 9/18/18 0:00:00 9/21/18 22:15:00 9/21/18 22:45:00 9/22/18 19:47: MicroCAT 65 N/A 180 9/18/18 0:00:00 9/21/18 22:15:00 9/21/18 22:45:00 9/22/18 19:48: MicroCAT 75 N/A 180 9/18/18 0:00:00 9/21/18 22:15:00 9/21/18 22:45:00 9/22/18 19:49: MicroCAT /18/18 0:00:00 9/21/18 22:15:00 9/21/18 22:45:00 9/22/18 19:50: MicroCAT 95 N/A 180 9/18/18 0:00:00 9/21/18 22:15:00 9/21/18 22:45:00 9/22/18 19:51: MicroCAT /18/18 0:00:00 9/21/18 22:15:00 9/21/18 22:45:00 9/22/18 19:52: MicroCAT /18/18 0:00:00 9/21/18 22:15:00 9/21/18 22:45:00 9/22/18 19:54: khz ADCP 125 N/A 600 9/22/18 0:00:00 N/A See Table 2 N/A See Table 2 9/22/18 19:57: XMC 134 N/A /21/18 21:00:00 9/21/18 22:15:00 9/21/18 22:45:00 9/22/18 20:01: MicroCAT /18/18 0:00:00 9/21/18 22:15:00 9/21/18 22:45:00 9/22/18 20:01: XMC /21/18 21:00:00 9/21/18 22:15:00 9/21/18 22:45:00 9/22/18 20:01: XMC /21/18 21:00:00 9/21/18 22:15:00 9/21/18 22:45:00 9/22/18 20:03: MicroCAT /18/18 0:00:00 9/21/18 22:15:00 9/21/18 22:45:00 9/22/18 20:03: MicroCAT 36m off bottom /18/18 01:00:00 9/22/18 05:01:00 9/22/18 05:42:00 9/23/18 01:07: MicroCAT 36m off bottom /18/18 01:00:00 9/22/18 05:01:00 9/22/18 05:42:00 9/23/18 01:07:00 * VMCM Spin start times The ADCPs were deployed in an upward-looking configuration. The instruments were programmed as described in Table 2. Before deployment, each instrument s transducer was rubbed gently by hand for 10 seconds to produce a spike in the data as a reference point to check the instrument s clock. Table 2. WHOTS-15 mooring ADCP deployment and configuration information. All times are in UTC. ADCP S/N 7637 ADCP S/N Frequency (khz) Number of Depth Cells

3 Depth Cell Size (m) 4 m 2 m Pings per Ensemble Time per Ensemble (min) 10 min 10 min Time per Ping (sec) 4 sec 2 sec Time of First Ping 09/22/18, 00:00:00 09/22/18, 00:00:00 Transducer 1 Spike Time 09/22/18, 01:15:00 09/22/18, 01:15:00 Transducer 2 Spike Time 09/22/18, 01:25:00 09/22/18, 01:25:00 Transducer 3 Spike Time 09/22/18, 01:35:00 09/22/18, 01:35:00 Transducer 4 Spike Time 09/22/18, 01:45:00 09/22/18, 01:45:00 Time in Water 09/22/18, 19:57:00 09/22/18, 19:45:00 Depth (m) 125 m 47.5 m 2. WHOTS-14 Mooring For the 14 th WHOTS mooring deployment that took place on 27 July 2017, UH provided 17 SBE-37 MicroCATs and one RDI Workhorse ADCP (300 khz). In addition to the instrumentation on the buoy, WHOI provided two Vector Measuring Current Meters (VMCM), one deep MircoCAT (SBE-37), and one RDI Workhorse ADCP (600 khz), and all required subsurface mooring hardware. The MicroCATs all measure temperature and conductivity, with 7 also measuring pressure. All MicroCATs were deployed with antifoulant capsules. Tables 3a and Table 3b provide the deployment information for these instruments on the WHOTS-14 mooring. Before deployment, a bag of ice was placed in contact with each MicroCAT s temperature sensor to produce a spike in the data as a reference point to check the instrument s clock. To produce a spike in the ADCP data each instrument s transducer was rubbed gently by hand for 10 seconds. Table 3a. WHOTS-14 mooring subsurface instrument deployment information. All times are in UTC (MM/DD/YY hh:mm:ss). SN Instrument Depth (m) Pressure SN Sample Interval (sec) Start Logging Data Cold Spike Begin Cold Spike End Time in Water 3617 MicroCAT 7 N/A 180 7/24/17 00:00:00 7/25/17 02:36:00 7/25/17 03:00:00 7/27/17 18:29: VMCM 10 N/A 60 7/27/17 00:00:17 7/27/17 18:25:00* N/A N/A 7/27/17 18:26: MicroCAT 15 N/A 60 7/24/17 0:00:00 7/25/17 02:36:00 7/25/17 03:00:00 7/27/17 18:19: MicroCAT 25 N/A 60 7/24/17 0:00:00 7/25/17 02:36:00 7/25/17 03:00:00 7/27/17 18:15: VMCM 30 N/A 60 7/26/17 19:54:00 7/27/17 18:10:00* N/A N/A 7/27/17 18:12: MicroCAT 35 N/A 60 7/24/17 0:00:00 7/25/17 02:36:00 7/25/17 03:00:00 7/27/17 18:07: MicroCAT 40 N/A 60 7/24/17 0:00:00 7/25/17 02:36:00 7/25/17 03:00:00 7/27/17 18:04: MicroCAT /24/17 0:00:00 7/25/17 02:36:00 7/25/17 03:00:00 7/27/17 18:02: khz See See Table 1825 ADCP 47.5 N/A 600 7/26/17 00:00:00 N/A Table 3b N/A 3b 7/27/17 19:30: MicroCAT 50 N/A 60 7/24/17 0:00:00 7/25/17 02:36:00 7/25/17 03:00:00 7/27/17 19:31: MicroCAT 55 N/A 60 7/24/17 0:00:00 7/25/17 02:36:00 7/25/17 03:00:00 7/27/17 19:33: MicroCAT 65 N/A 60 7/24/17 0:00:00 7/25/17 02:36:00 7/25/17 03:00:00 7/27/17 19:35: MicroCAT 75 N/A 180 7/24/17 0:00:00 7/25/17 02:36:00 7/25/17 03:00:00 7/27/17 19:36: MicroCAT 85 N/A 180 7/24/17 0:00:00 7/25/17 02:36:00 7/25/17 03:00:00 7/27/17 19:38: MicroCAT /24/17 0:00:00 7/25/17 02:36:00 7/25/17 03:00:00 7/27/17 19:40: MicroCAT /24/17 0:00:00 7/25/17 02:36:00 7/25/17 03:00:00 7/27/17 19:42: MicroCAT /24/17 0:00:00 7/25/17 02:36:00 7/25/17 03:00:00 7/27/17 19:54:00 3

4 khz ADCP 125 N/A 600 7/24/17 0:00:00 N/A See Table 3b N/A See Table 3b 7/27/17 19:55: MicroCAT /24/17 0:00:00 7/25/17 02:36:00 7/25/17 03:00:00 7/27/17 19:57: MicroCAT /24/17 0:00:00 7/25/17 02:36:00 7/25/17 03:00:00 7/27/17 19:59: MicroCAT 36m off bottom N/A 60 7/24/17 0:00:00 7/25/17 02:36:00 7/25/17 03:00:00 7/28/17 02:02: MicroCAT 36m off bottom /20/17 1:00:00 7/25/17 02:36:00 7/25/17 03:00:00 7/28/17 02:02:00 Table 3b. WHOTS-14 mooring ADCP deployment and configuration information. All times are in UTC. ADCP S/N 4891 ADCP S/N 1825 Frequency (khz) Number of Depth Cells Depth Cell Size (m) 4 m 2 m Pings per Ensemble Time per Ensemble (min) 10 min 10 min Time per Ping (sec) 4 sec 2 sec Time of First Ping 07/24/17, 00:00:00 07/26/17, 00:00:00 Transducer 1 Spike Time 07/26/17, 00:30:00 07/26/17, 00:30:00 Transducer 2 Spike Time 07/26/17, 00:30:15 07/26/17, 00:30:15 Transducer 3 Spike Time 07/26/17, 00:30:30 07/26/17, 00:30:30 Transducer 4 Spike Time 07/26/17, 00:30:45 07/26/17, 00:30:45 Time in Water 07/27/17, 19:55:00 07/27/17, 19:30:00 Depth (m) 125 m 47.5 m 3. WHOTS-14 Recovery The WHOTS-14 mooring was recovered on September 26 th 27 th 2018 (UTC). All instruments on the mooring were successfully recovered. Most of the instruments had some degree of biofouling, with the heaviest fouling near the surface. Fouling extended down to the ADCP at 125 m, although it was minor at that depth. MicroCATs All MicroCATs were in good condition after recovery. MicroCAT 6896 (40 m) had a barnacle attached at the top end of its conductivity cell, partially blocking the flow (Fig. 1); and MicroCAT 6894 (25 m) had its anti-fouling plug slightly displaced (Fig. 2). After recovery and before stop recording, a bag of ice was placed in contact with each MicroCAT temperature sensor, to produce a spike in the data as a reference point to check the instrument s clock. To produce a spike in the ADCP data, each instrument s transducer was rubbed gently by hand for 20 seconds. The data from all instruments were downloaded on board the ship, and all instruments returned full data records. Table 4 gives the post-deployment information for the C-T and ADCP instruments. 4

5 Figure 1. WHOTS-14, MicroCAT SN 6896 at 40 m, recovered with a barnacle partially blocking the top end of its conductivity cell. Figure 2. WHOTS-14, MicroCAT SN 6894 at 25 m, recovered with its anti-fouling plug slightly displaced. 5

6 Table 4. WHOTS-14 mooring C-T and ADCP Instruments recovery information. All times are in UTC. Depth (m) Sea-Bird Serial # 7 SBE SBE SBE SBE SBE SBE ADCP SBE SBE SBE SBE SBE SBE SBE SBE ADCP SBE SBE mab SBE mab SBE Time out of water Time of Spike Time of End Spike 9/27/18 9/27/18 9/27/18 01:45:00 05:21:00 5:51:00 9/27/18 9/27/18 9/27/18 01:49:00 05:21:00 5:51:00 9/27/18 9/27/18 9/27/18 01:54:00 05:21:00 5:51:00 9/27/18 9/27/18 9/27/18 01:58:00 05:21:00 5:51:00 9/27/18 9/27/18 9/27/18 01:59:00 05:21:00 5:51:00 9/27/18 9/27/18 9/27/18 02:03:00 05:21:00 5:51:00 9/27/18 N/A See Table 5 00:34:00 9/27/18 9/27/18 9/27/18 00:34:00 05:21:00 5:51:00 9/27/18 9/27/18 9/27/18 00:33:00 05:21:00 5:51:00 9/27/18 9/27/18 9/27/18 00:32:00 05:21:00 5:51:00 9/27/18 9/27/18 9/27/18 00:25:00 05:21:00 5:51:00 9/27/18 9/27/18 9/27/18 00:24:00 05:21:00 5:51:00 9/27/18 9/27/18 9/27/18 00:23:00 05:21:00 5:51:00 9/27/18 9/27/18 9/27/18 00:23:00 05:21:00 5:51:00 9/27/18 9/27/18 9/27/18 00:21:00 05:21:00 5:51:00 9/27/18 N/A See Table 5 00:19:00 9/27/18 9/27/18 9/27/18 00:15:00 05:21:00 5:51:00 9/27/18 9/27/18 9/27/18 00:14:00 05:21:00 5:51:00 9/26/18 9/27/18 9/27/18 20:18:00 05:21:00 5:51:00 9/26/18 9/27/18 9/27/18 20:18:00 05:21:00 5:51:00 Time Logging Stopped 9/27/18 06:55:00 9/28/18 04:34:00 9/28/18 04:29:30 9/29/18 01:11:30 9/28/18 01:05:00 9/28/18 04:32:00 9/30/18 01:42:00 9/27/18 06:32:00 9/27/18 06:27:30 9/27/18 06:39:00 9/27/18 06:58:00 9/27/18 06:52:30 9/27/18 06:49:00 9/27/18 06:15:00 9/27/18 06:18:00 9/30/18 00:15:00 9/27/18 06:06:30 9/27/18 06:12:30 9/27/18 06:36:00 9/27/18 04:27:30 Samples Logged Data Quality File Name Good 3617_recovery.cap Good 6893_recovery.cap Good 6894_recovery.cap Good 6895_recovery.cap Good 6896_recovery.cap Good 6887_recovery.cap Good WH14_ Good 6897_recovery.cap Good 6898_recovery.cap Good 6899_recovery.cap Good 3618_recovery.cap Good 3634_recovery.cap Good 3670_recovery.cap Good 6889_recovery.cap Good 6890_recovery.cap Good WH14_ Good 6888_recovery.cap Good 6891_recovery.cap Good 9988_recovery.cap Good 10602_recovery.ca p The data recovered from the MicroCATs appear to be of high quality, although postdeployment calibrations and quality control are required. Figures A1-A18 show the nominally calibrated temperature, conductivity and salinity records from each instrument, and pressure for those instruments that were equipped with pressure sensors. 6

7 ADCP Table 5 provides the WHOTS-14 ADCP deployment configuration and recovery information. Table 5. WHOTS-14 mooring ADCP recovery information. All times are in UTC. ADCP S/N 4891 ADCP S/N 1825 Frequency (khz) Number of Depth Cells Depth Cell Size (m) 4 m 2 m Pings per Ensemble Time per Ensemble (min) 10 min 10 min Time per Ping (sec) 4 sec 2 sec Time of First Ping 07/24/17, 00:00:00 07/26/17, 00:00:00 Transducer 1 Spike Time 09/28/18, 02:31:10 09/28/18, 02:36:50 Transducer 2 Spike Time 09/28/18, 02:31:20 09/28/18, 02:37:00 Transducer 3 Spike Time 09/28/18, 02:31:30 09/28/18, 02:37:10 Transducer 4 Spike Time 09/28/18, 02:31:40 09/28/18, 02:37:20 Time in Water 07/27/17, 19:55:00 07/27/17, 19:30:00 Time out of Water 09/27/18, 00:19:00 09/27/18 00:34:00 Depth (m) 125 m 47.5 m *WHOTS-14 VMCM recovery information is provided in Table ZZZ [See A. Plueddemann for this ] The fouling on the 300 khz ADCP transducer faces (Figure 3) was minimal, most likely due to the depth of deployment (125 m) as well as Destin rash paste (which contains 40% Zinc oxide) used as anti-foulant on the faces. The transducer faces for the 47.5 m ADCP (Figure 4) were also treated with Destin paste, and despite significant algae growth near the faces, the faces themselves did not show the same level of growth. 7

8 Figure 3. WHOTS-14 ADCP (300 khz) deployed at 125 m, after recovery. Figure 4. WHOTS-14 ADCP (600 khz) deployed at 47.5 m, after recovery. 8

9 300 khz ADCP The data from the upward-looking 300 khz ADCP at 125 m were good; the instrument was pinging upon recovery. There appears to be no obviously questionable data from this ADCP at this time, apart from near-surface side-lobe interference. Figure 5 shows the variations of the horizontal and vertical components of velocity in depth and time. Figure 6 shows the heading, pitch and roll information from the ADCP. 600 khz ADCP The data from the upward-looking 600 khz ADCP at 47.5 m were good; the instrument was pinging upon recovery. There appears to be no initial questionable data from this ADCP at this time, apart from near-surface side-lobe interference. Figure 7 shows the variations of the horizontal and vertical components of velocity in depth and time. Figure 8 shows the heading, pitch and roll information from the ADCP. 9

10 . Figure 5. Time-series of eastward, northward and upward velocity components versus bin number measured by the ADCP at 125 m depth on the WHOTS-14 mooring. Height in meters above the transducer is approximately 4 times the bin number. Current speeds greater than 1 m/s are not included. Color bar gives current speed in m/s. 10

11 Figure 6. Heading, pitch and roll variations measured by the ADCP at 125 m depth on the WHOTS-14 mooring. 11

12 . Figure 7. Time-series of eastward, northward and upward velocity components versus bin number measured by the ADCP at 47.5 m depth on the WHOTS-14 mooring. Height in meters above the transducer is approximately 2 times the bin number. Current speeds greater than 1 m/s are not included. Color bar gives current speed in m/s. 12

13 Figure 8. Heading, pitch and roll variations measured by the ADCP at 47.5 m depth on the WHOTS-14 mooring. 13

14 4. CTD Stations UH provided CTD and water sampling equipment, including a Sea-Bird 9/11+ CTD sampling pressure, dual temperature, dual conductivity and dual oxygen sensors at 24 Hz. Sea- Bird sensors used routinely as part of the Hawaii Ocean Time-series were employed to tie the WHOTS cruise data into the HOT CTD dataset with frequent sensor calibrations. The CTD was installed inside a twelve-place General Oceanics rosette with six 5-liter Niskin sampling bottles controlled by a Sea-Bird carousel. GPS data were not available to provide NMEA position and time to the CTD deck box. Table 6 provides summary information for all CTD casts, and figures B1-B7 show the water column profile information that was obtained. Table 6. CTD stations occupied during the WHOTS-15 cruise. Station/cast Date (MM/DD/YYYY, UTC) In-water Time (HH:MM,UTC) Location Maximum pressure (dbar) 20/1 09/22/ : N, W / 1 09/23/ : N, W / 2 09/23/ : N, W / 3 09/23/ : N, W / 4 09/24/ : N, W / 5 09/24/ : N, W / 1 09/25/ : N, W / 2 09/25/ : N, W / 3 09/25/ : N, W / 4 09/26/ : N, W / 5 09/26/ : N, W / 6 09/28/ : N, W 213 Twelve CTD casts were conducted during the WHOTS-15 cruise, from September 21 through 28. CTD profile data were collected at Station 20 (in transit to the WHOTS mooring), Station 50 (near the WHOTS-15 buoy), and Station 52 (near the WHOTS-14 buoy). The cast at Station 20 was 1500 m deep, and three acoustic releases (two to be used in the WHOTS-15 mooring and one backup) were attached to the rosette frame for function testing. Six CTD yo-yo casts were conducted to obtain profiles for comparison with subsurface instruments on the WHOTS-15 mooring after deployment, and five yo-yo casts were conducted for comparison with the WHOTS-14 mooring before recovery. These casts were started about 0.25 nm from the buoys with varying drift during each cast, and consisted of 5 up-down cycles between near the surface and 200 to 210 m. The primary oxygen showed more hysteresis than the secondary sensor, and it also experienced a slow drift toward smaller values during the cruise. Water samples were taken from all casts; 3 to 4 samples for each of them. These samples were to be analyzed for salinity at UH and used to calibrate the CTD conductivity sensors. 5. Thermosalinograph Near-surface temperature and salinity data during the WHOTS-15 cruise were acquired from the thermosalinograph (TSG) system installed on the NOAA Ship Hi ialakai. The sensors were sampling water from the continuous seawater system running through the ship, and were 14

15 comprised of one thermosalinograph model SBE-21 (SN 3155) and a micro-thermosalinograph model SBE-45 (SN ), both with (internal) temperature and conductivity sensors located in the ship s wet lab (Fig. 9), about 67 m from separate hull intakes; and an SBE-38 (SN 215) external temperature sensor located at the entrance to one of the water intakes. The SBE-21 recorded data every 6 seconds, and the other two instruments recorded data every second. The water intake for the SBE-21 and SBE-38 is located at the bow of the ship, next to the starboard side bow thruster (Fig. 10) at a depth of 2 m. The intake for the SBE-45 is located near the middle of the ship, also 2 m deep. The system has a pressure gauge showing a flow pressure of about 10 psi during the cruise. Each thermosalinograph system had a debubbler. Figure 9. Location of the SBE-21 (1) and SBE-45 (2) thermosalinographs in the wet lab on board the NOAA ship Hi ialakai. The debubblers (4), and the water exhaust (3) used to take water samples for salinity analysis are also shown. 15

16 Figure 10. Picture of the bow thruster room on board the NOAA Ship Hi ialakai, indicating the location of the SBE-38 temperature sensor at the entrance of the seawater intake (2). Both thermosalinographs exhibited a number of conductivity and temperature glitches, especially the SBE-21 (Fig. 11a). The temperature differences between the internal SBE-45 and SBE-21 were between 0.4 and 0.8 C (Fig. 11b, middle), however the computed salinity differences between these two instruments was between and 0.03 g/kg (Fig. 11b, bottom). A diurnal cycle is apparent in the temperature and conductivity. The ship s navigation data during the cruise are plotted in Fig. 11c. 16

17 Figure 11a. Time-series of temperature (top), conductivity (middle), and salinity (bottom) from the Ship Hi ialakai s thermosalinographs SBE-21, and SBE-45; and temperature from the remote SBE-38 sensor during the WHOTS-15 cruise operations near the WHOTS-14 and WHOTS-15 moorings. 17

18 Figure 11b. Temperature difference between SBE-38 remote and SBE-21 thermosalinograph sensors (top), and between the SBE-21 and SBE-45 sensors (middle); and salinity difference between the SBE-45 and SBE- 21 instruments during the WHOTS-15 cruise operations near the WHOTS-14 and WHOTS-15 moorings. 18

19 Figure 11c. Time-series of Ship Hi ialakai navigation data during the WHOTS-15 cruise operations near the WHOTS-14 and WHOTS-15 moorings. 19

20 6. Shipboard ADCP Currents were measured for the duration of the cruise over the depth range of m with a 75 khz RDI Ocean Surveyor (OS75) ADCP working in narrowband mode with a vertical resolution of 16 m, and in broadband mode with vertical resolution of 8 m. The system yielded good data, shown in Figures 12 and 13 during operations near the WHOTS-14 and WHOTS-15 moorings. Periods of missing data between 300 and 450 m in the broadband ADCP are apparently due to the lack of scattering material in the water. 20

21 Figure 12. Contours of zonal (upper) and meridional (lower) speeds as a function of depth and time (UTC) from the narrowband ADCP on the NOAA Ship Hi ialakai during the WHOTS-15 cruise operations near the WHOTS-14 and WHOTS-15 moorings. Positive is to the East (North). 21

22 Figure 13. Same as in Figure 12, but for the broadband ADCP. 22

23 7. Weather and Currents See Appendix C for the weather and currents observed during the WHOTS-15 cruise. 23

24 Appendix A. Moored C-T Time Series Figures 24

25 Figure A1. Temperature, conductivity and salinity time-series from MicroCAT SBE-37 SN 3617 deployed at 7 m on the WHOTS-14 mooring. Pre-deployment calibration information was used. Nominal pressure for deployed depth used to calculate salinity. 25

26 Figure A2. Temperature, conductivity and salinity time-series from MicroCAT SBE-37 SN 6893 deployed at 15 m on the WHOTS-14 mooring. Pre-deployment calibration information was used. Nominal pressure for deployed depth used to calculate salinity. 26

27 Figure A3. Temperature, conductivity and salinity time-series from MicroCAT SBE-37 SN 6894 deployed at 25 m on the WHOTS-14 mooring. Pre-deployment calibration information was used. Nominal pressure for deployed depth used to calculate salinity. 27

28 Figure A4. Temperature, conductivity and salinity time-series from MicroCAT SBE-37 SN 6895 deployed at 35 m on the WHOTS-14 mooring. Pre-deployment calibration information was used. Nominal pressure for deployed depth used to calculate salinity. 28

29 Figure A5. Temperature, conductivity and salinity time-series from MicroCAT SBE-37 SN 6896 deployed at 40 m on the WHOTS-14 mooring. Pre-deployment calibration information was used. Nominal pressure for deployed depth used to calculate salinity. 29

30 Figure A6. Pressure, temperature, conductivity and salinity time-series from MicroCAT SBE-37 SN 6887 deployed at 45 m on the WHOTS-14 mooring. Pre-deployment calibration information was used. 30

31 Figure A7. Temperature, conductivity and salinity time-series from MicroCAT SBE-37 SN 6897 deployed at 50 m on the WHOTS-14 mooring. Pre-deployment calibration information was used. Nominal pressure for deployed depth used to calculate salinity. 31

32 Figure A8. Temperature, conductivity and salinity time-series from MicroCAT SBE-37 SN 6898 deployed at 55 m on the WHOTS-14 mooring. Pre-deployment calibration information was used. Nominal pressure for deployed depth used to calculate salinity. 32

33 Figure A9. Temperature, conductivity and salinity time-series from MicroCAT SBE-37 SN 6899 deployed at 65 m on the WHOTS-14 mooring. Pre-deployment calibration information was used. Nominal pressure for deployed depth used to calculate salinity. 33

34 Figure A10. Temperature, conductivity and salinity time-series from MicroCAT SBE-37 SN 3618 deployed at 75 m on the WHOTS-14 mooring. Pre-deployment calibration information was used. Nominal pressure for deployed depth used to calculate salinity. 34

35 Figure A11. Temperature, conductivity and salinity time-series from MicroCAT SBE-37 SN 3634 deployed at 85 m on the WHOTS-14 mooring. Pre-deployment calibration information was used. Nominal pressure for deployed depth used to calculate salinity. 35

36 Figure A12. Pressure, temperature, conductivity and salinity time-series from MicroCAT SBE-37 SN 3670 deployed at 95 m on the WHOTS-14 mooring. Pre-deployment calibration information was used. 36

37 Figure A13. Pressure, temperature, conductivity and salinity time-series from MicroCAT SBE-37 SN 6889 deployed at 105 m on the WHOTS-14 mooring. Pre-deployment calibration information was used. 37

38 Figure A14. Pressure, temperature, conductivity and salinity time-series from MicroCAT SBE-37 SN 6890 deployed at 120 m on the WHOTS-14 mooring. Pre-deployment calibration information was used. 38

39 Figure A15. Pressure, temperature, conductivity and salinity time-series from MicroCAT SBE-37 SN 6888 deployed at 135 m on the WHOTS-14 mooring. Pre-deployment calibration information was used. 39

40 Figure A16. Pressure, temperature, conductivity and salinity time-series from MicroCAT SBE-37 SN 6891 deployed at 155 m on the WHOTS-14 mooring. Pre-deployment calibration information was used. 40

41 Figure A17. Pressure, temperature, conductivity and salinity time-series from MicroCAT SBE-37 SN deployed at 35 m above the bottom on the WHOTS-14 mooring. Pre-deployment calibration information was used. 41

42 Figure A18. Temperature, conductivity and salinity time-series from MicroCAT SBE-37 SN 4743 deployed at 35 m above the bottom on the WHOTS-14 mooring. Pre-deployment calibration information was used. Nominal pressure for deployed depth used to calculate salinity. 42

43 Appendix B. CTD Profiles 43

44 Figure B1. Profiles of 2 Hz temperature, salinity, potential density and oxygen data during the CTD at station

45 Figure B2. Profiles of 2 Hz temperature, conductivity, salinity, and oxygen data during S52C1 and S52C2. 45

46 Figure B3. Profiles of 2 Hz temperature, conductivity, salinity, and oxygen data during S52C3 and S52C4. 46

47 Figure B4. Profiles of 2 Hz temperature, conductivity, salinity, and oxygen data during S52C5 and S50C1. 47

48 Figure B5. Profiles of 2 Hz temperature, conductivity, salinity, and oxygen data during S50C2 and S50C3. 48

49 Figure B6. Profiles of 2 Hz temperature, conductivity, salinity, and oxygen data during S50C4 and S50C5. Figure B7. Profiles of 2 Hz temperature, conductivity, salinity, and oxygen data during S50C6. 49

50 Appendix C. WHOTS-14 Weather and Currents Weather During the WHOTS-14 cruise, a low pressure system north-northwest of Kauai was drawing up tropical moisture from the south, producing light south to southeasterly winds at Station ALOHA (Fig. C1), creating hot and humid weather conditions (Fig. C2). Conditions during the WHOTS-15 deployment on September were favorable, with light ESE winds of ~ 5 kt increasing to up to 16 kt by the end of the deployment, and 1.5 m waves from the east (Fig. C3), with a strong surface current towards ENE (see Currents section below). Figure C1. The NOAA/NCEP GFS surface wind and sea level pressure analysis for the central-eastern North Pacific, valid for 12Z on September 23 rd,

51 Figure C2. GOES-10 8 km Water Vapor Image for the central-eastern North Pacific at 21:30Z on September 23 rd, 2018 Figure C3. Significant wave height from the NOAA Wave Watch III forecast on September 23 rd, 2018, 18:00Z. Weather conditions were favorable on September 26-27, during the WHOTS-14 recovery, with winds ~7 kt from the SSW, with a surface current towards the ESE. 51

52 A hurricane that developed SW of the Big Island (Fig. C4) was forecast to pass over French Frigate Shoals, where NOAA scientists were conducting observations. Consequently, science operations were stopped on September 28 th at 18:40, and the ship was re-routed to pick up the observers and their equipment. Figure C4. GOES-10 8 km Water Vapor Image for the central-eastern North Pacific at 00:00Z on October 1 st, Currents The shipboard ADCP CODAS real-time data management, processing and display system software was used to monitor the currents during the cruise. Near-surface currents were nearly 1 kt NWward during transit to Station ALOHA, turning Nward and Eward upon arrival to Station ALOHA, and remained so for approximately five days (Fig. C5). There was a nearly stationary cyclonic eddy east of ALOHA (Fig. C6), suggesting a possible increasing geostrophic flow towards the E, NE. A combination of internal semidiurnal and diurnal tides, along with near-inertial oscillations, were noticeable especially in vertical shear (Figs. 12, 13, and C7). 52

53 Figure C5. History of shipboard 75 khz ADCP (OS75bb) current measurements from September 22 nd, 21:50z (top left), from September 23 rd, 21:50z (top right), and from September 27 th, 23:20z (bottom) averaged over depths from 31 to 71 m. Water temperature at the hull transducer depth is indicated by vector color. 53

54 Figure C6. Sea surface height from the NRL 1/12 th degree HYCOM analysis for 00Z on September 26 th, 2018 (left) and surface currents (right). Figure C7. Shipboard 75 khz ADCP (OS75nb) currents on September 28 th as a function of depth and time. 54

55 Appendix D. Acoustic receiver to detect the presence of tagged sharks near the WHOTS mooring As part of the project titled Community engagement in a telemetry and social study to reduce mortality to a threatened species (see details below), one of the intern students in that project (Kelsey Maloney) installed a Vemco VR2W- 69 khz acoustic receiver in the WHOTS-15 mooring, clamped together with the 25 m MicroCAT (see Fig. D1). The receiver is programmed to detect and internally record data transmitted by acoustic tags that have been implanted inside of sharks or pelagic fishes, recording their serial number, date, time, and other parameters. The instrument, rated to a maximum depth of 500 m, was wrapped with electric tape to prevent biofouling, and it was mounted onto the 25 m MicroCAT load bar using two modified MicroCAT clamps. Figure D1. Vemco VR2W- 69 khz acoustic receiver (black) mounted onto the 25 m MicroCAT loading bar, before being attached to the WHOTS-15 mooring and deployed. Project description Project title: Community engagement in a telemetry and social study to reduce mortality to threatened shark species. 55

56 Principal Investigator: Dr. Melanie Hutchinson, JIMAR Marine Researcher/ Affiliate Faculty, Hawaii Institute of Marine Biology, Lilipuna Rd. Kaneohe, Hawaii NMFS Collaborating Scientists: Keith Bigelow, Supervisor, International Fisheries Program, Fisheries Research & Monitoring Division, Pacific Islands Fisheries Science Center (PIFSC). Dr. Kirsten Leong, Social Scientist, Socioeconomics Program, Ecosystem Sciences Division, PIFSC. Background and Justification: Oceanic whitetip sharks (Carcharhinus longimanus) are a large component of the shark bycatch in tuna purse seine and longline fisheries worldwide (Rice and Harley, 2012). Oceanic whitetip shark (OCS) populations, historically one of the most numerically abundant species in tropical waters (Bonfil et al. 2008), have undergone significant declines in all oceans. A stock assessment conducted by the Secretariat to the Pacific Community found the OCS population in the Pacific Ocean to be overfished and overfishing was still occurring (Rice & Harley, 2012). In 2014 OCS were listed in appendix II of CITES, and in 2018 NMFS listed OCS as threatened under the U.S. Endangered Species Act (ESA). Locally, OCS have also shown significant declines in relative abundance in the Hawaii longline fishery since 1995 (Walsh and Clarke, 2011; Brodziak & Walsh, 2015). In an effort to re-build the stock, fisheries scientists have called for additional research on the reproductive biology of this species and for tagging studies to gain a better understanding of the basic ecology and stock structure (Rice and Harley, 2012). OCS are highly migratory and wide ranging with horizontal displacements of tagged individuals ranging up to 2,811 km (Kohler et al. 1998). Until recently, few studies had focused on OCS movements to identify migratory patterns. However, evidence of residency and philopatry was recently documented in two studies on OCS tagged in the Atlantic Ocean (Howey-Jordan et al. 2013, Tolotti et al. 2015b). Anecdotal observations indicate that OCS are found in association with Fish Aggregating Devices (FADs) which, because of their importance in tuna fisheries, increases the vulnerability of OCS to fishing mortality in FAD based fisheries (e.g. purse seine, troll, handline). This project addresses the need to understand FAD associative behavior in this species and others that are vulnerable to capture in FAD based fisheries (such as the silky shark, Carcharhinus falciformis) to devise interaction mitigation strategies. Furthermore, habitat use and movement behavior of OCS and silky sharks (FAL) around Hawaii is unknown. In this study we have initiated a large community tagging program to elucidate spatial and temporal hotspots including areas of biological significance for these populations in and around Hawaii. If Hawaii is an important habitat for mating or partuition, it is critical to population growth that strategies to reduce mortality in recreational and commercial fisheries in these regions be identified. These data may also enhance the Hawaii troll and handline fisheries by elucidating times and areas of residency when fishers can improve their practices and reduce costs related to OCS depredation. In addition to the observation that OCS & FAL are FAD associated, informal discussions with local fishers have anecdotally highlighted the belief that they are also seasonally resident at the FADs, and there is a general rule of three protocol for these encounters among commercial and sport FAD fishers. That is, if the same shark is captured three times or takes three fish, it is killed via a variety of means (e.g. shooting them with a gun, feeding them hooked bait with cable leaders and a large float attached). If widespread throughout the fishery, these actions have the potential to seriously affect the OCS population. Thus, in addition to the collection of habitat use information in a telemetry study, we propose collection of social data to empirically assess anecdotal observations and better understand the attitudes and beliefs of the fishing community. 56

57 Kona fishers willingness to cooperate with scientists has been demonstrated through their participation on tagging trips and voluntary follow-up. There is great potential to change their attitudes with respect to oceanic sharks and by extension affect their shark handling practices through outreach and education in a community-based tagging study. This presents a valuable opportunity to find a collaborative solution to reduce depredation and mortality in Hawaii s fisheries. Pursuing this goal cooperatively by utilizing both scientific and local knowledge may produce the most feasible and effective resource management approaches (Reed, Dougill, & Taylor, 2006). Scientists would benefit from the community s experiential knowledge of OCS & FAL behavior. In turn, the hope is that increasing the community s scientific literacy will benefit the sustainability of their fishery. Informal fisher education has already produced increased concern and engagement. The specific research objectives of this study are to engage with local fishers to 1) participate in an electronic and ID tagging study that will acquire data to inform conservation engineering efforts to reduce OCS & FAL bycatch in both the FAD associated purse seine fishery and the Hawaiian troll and handline fisheries, 2) evaluate their attitudes and behaviors around OCS & FAL interactions, and identify the outreach tools and cooperative methods most likely to reduce shark bycatch and mortality. We will gain insight into the dynamics of FAD associated behavior and identify potential spatial and temporal mitigation patterns (e.g. seasonal periodicity and migration routes). Our results will also provide the first characterization of the local ecological knowledge, Figure 1. State anchored FAD locations around Oahu and Hawaii islands. Areas encircled in yellow will be the focus of the tagging efforts and locations of instrumented FADs. FADs; F, VV, C, UU, B &TT have already been instrumented with acoustic receivers. demographic composition, and social network structure of the Kona troll and handline fisheries, allowing us to evaluate the current state of OCS & FAL-fishery interactions in the context of participant knowledge, motives, demography, and social networks. The limited size and scope of the Kona fisheries make them excellent candidates for such a study. The fishing community may serve as a model in social structure and outreach efficacy for other communities in the MHI and Pacific territories. Methodology: In Hawaii, OCS & FAL appear to be occasionally resident at anchored FADs and are also found in association with tuna schools and pilot whales. The proximity of the anchored FADs to shore means that conducting this work in Hawaii would be the most costeffective place in the world to acquire an understanding of OCS & FAL vertical behavior and residency at FADs and could serve as model of FAD associated behavior around drifting FADs in other regions (Dagorn et al., 2010). In this proposal we are requesting funds to begin a tagging study to: 57

58 (1) Assess OCS affiliation, continuous residence times and vertical behavior around anchored FADs as a means of identifying potential spatial bycatch mitigation strategies for the FAD associated purse seine fishery. (2) Illustrate movement behavior and habitat use on and off FADs to inform selectivity/catchability parameters in stock assessments. (3) Assess stock structure, migratory patterns and identify hot spots or areas of biological significance around Hawaii for a species threatened with endangerment. To accomplish these goals, we have trained local fishers to tag incidental oceanic whitetip sharks with an acoustic tag (Vemco v16p R-coded 69 KHz acoustic transmitters - Amirix Systems Inc. Nova Scotia, Canada). To investigate fidelity and residence times at FADs, moorings have been instrumented with VR2-W underwater receivers. Acoustic data will signify times of arrivals/departures and continual residence times at the FADs. To elucidate both vertical and horizontal movement behavior, sharks will be tagged with PAT tags (MiniPAT, Wildlife Computers Inc. Redmond, WA). 58