Daily Logs
Day One
17 July 1600 Load ship, calibrate SeaBird CTD for oxygen, depart dock at midnight
18 July 0800 Approach Southwest Pass of the Mississippi River, 23 psu
0900 Collect series of salinities from 23 to as low as possible, 3 psu, for nutrient gradient
1130 Arrive station A’1, strong oxycline near bottom at 8 m, 0.5 mg/L
1230 Depart for next series of A’ transects
1600 Depart from end of A’ line to head to A7, southern end of A trans
1800 Jenn and Sam see a shark
Very low oxygen across most of the trans A, mostly less than 0.5 mg/L
2100 Blue crabs, Callinectes similis, both ovigerous females and males swimming at surface of the water avoiding low oxyen near the bottom 0.1 – 0.2 mg/L
2300 Nearshore station mixed; depart trans A to trans B, inshore end Day Two
19 July 0100 New day, new transect, low oxygen
Several jellyfish, Quinquecira quenqueloculina (?) in subsurface water
Some blue crabs, C. similis, at the surface
0200 A bit farther SE on trans B. Lots of sea nettles in the water. Smaller portunid crab at the surface. Low oxygen below.
Small shark at B4; paired unidentifiable fish.
0400 Large needlefish at surface, B6.
0700 Low oxygen out to B9, almost 40 m
Thunderstorms as cold front approaches
0730 Out to B10, 50 m, just on edge of low oxygen, 1.92 mg/L
Close it off at 57 m
0800 Start on SE end of trans C, working towards shore
Hypoxia not as extensive in deeper waters on trans C.
1500 Within 25 m contour, hypoxia on trans C, 0.9 at C7
1600 *Station C6C* and successful box coring at C6B, Jenn for foraminiferans and Ling for diatoms
1900 Station C4 with close to anoxia. Successful box coring Jenn has samples for foraminiferans at a station not normally this low in dissolved oxygen
Crew change for scientists
2100 Nearshore, north end of trans C in 5 m, normal oxygen. Headed to D’1
2300 End of day, low oxygen Day 3
0200 Severely low oxygen on many trans D’ stations, 0.2 mg/L from 15 m to 30 m. Benthic eel, portunid crabs, and penaeid shrimp swimming at surface
0900 Arrival of Canadian Broadcast Corporation, Jackie Corkery, producer, documentary series, film and sound crew, for the coastal ocean portion of a 4-part series on the ocean. Landed at D3 via the R/V Acadiana
Day 4
16 July 2009: Dr. Brian Roberts, LUMCON, reported extremely low oxygen concentrations within Atchafalaya Bay below 1 mg/L, including F0. Several supersaturated surface waters.]
Day 5
22 July 0130 End trans H on inshore end in 8 m, no hypoxia, as low as 2.4 mg/L
Depart trans H and head to inshore end of trans I, still rough, mixing shallower waters
0300 Trans I seems to be well-mixed as well. No wonder, persistent 17-20 kn winds with 6 ft swells. Again, a gift from the sea goddess for the night crew.
0700 Well mixed nearer shore, but thin layer of hypoxia begins in 20 m out to 30 m
1245 Into deeper water on trans I (31 m) and out of hypoxic zone
Transit to offshore end of trans J
1500 Offshore end of trans J in 3 mg/L
1830 No low oxygen so far on trans J, seas calm down for night shift, finally!
2100 Sta J4, no low oxygen, box coring for forams and diatoms, 3 for 3, plus one to grow on.
2400 Finished with trans J, no hypoxia, headed west to trans K, inshore end Day 6
23 July 0130 Begin inshore end of trans K in 6 m depth off Cameron LA
0330 Midway on trans K, no low oxygen.
0730 End of trans K, no low oxygen
0800 Head to trans off Sabine, TX/LA border to finish out grid and look for any remnants of hypoxia from earlier in month and late June
0900 Offshore end of trans M, no low oxygen
1700 Inshore end of trans S northeast of Galveston, no low oxygen; finish off grid and look for any remnants of hypoxia from earlier in month and late June
2130 End of trans S, no low oxygen
2200 Heading to port, Cocodrie, numbers being calculated and explained and compared.
P.S. This is the end of our SILVER ANNIVERSARY cruise. The first shelfwide cruise was in 1985. Three participants from that cruise are on board for this cruise, Nancy Rabalais, LUMCON; Jim Lee, LSU; Sam LeBouef, LUMCON. Gene Turner from LSU was also present on the summer 1985 cruise.
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