LMG03-02 Weekly Cruise Report

3 March 2003

The RV Laurence M. Gould (LMG) spent Monday (2/24) conducting marine mammal surveys near the ice edge at the northeast tip of Alexander Island and south into the month of George Sound. Conditions were good for the Zodiac, and a total of 4 humpback and 1 minke biopsies were collected. At 1800, the SIO/IWC group decided that their highest priority was to head north though in the inner passage and return to S1A (north of Palmer Station) and recover S1A and deploy its replacement S1B before returning to Palmer Station on Sunday (3/2). If we did not do this, the only chance to pick up S1A and reset S1B would be on the Palmer Station to Punta Arenas transit, and if the weather then was too rough, S1A would have to be left. This plan made sense, so after making a CTD cast to the bottom (1600 m) of George Sound, we started north and deployed the remaining three WHOI isobaric floats at night and arrived back at C1 on Tuesday morning to try to drag up the remaining bottom segment. Towards the end of the second drag, the tensions increased steadily to 14,283 pounds and with a great shudder, the Dush 6 (old Markey) winch pulled lose from its ring stand and came to a stop about 20 ft back on the 01 deck, pressed against one of the Zodiacs. The tension remained very high, above 10,000 pounds for a few minutes as the bridge backed the ship down. With the tension less than 1000 pounds, the drag wire was cut and the crew went to work to secure the winch and clean up hydraulic spilled on the deck when the hydraulic connections were sheared off.

Once ready, we headed north and stopped overnight at Rothera before continuing up the inner passage. We encountered several miles of solid heavy ice in Tickle Passage but Captain Robert was able to break through to ice-free Hanusse Bay, where at least 14 humpbacks, 3 minke, and 3 orcas were observed and photographed from the Zodiacs, and two biopsies collected. The LMG then continued north to Port Lockroy, where we hove to while the winch was repositioned on its stand and a through inspection made to determine what caused the winch to fail and what parts were needed to make the winch ready for the next cruise. The ship then continued north through Gerlache Strait and north to S1A, arriving Friday afternoon. Once S1A was recovered and S1B deployed, the ship headed for Deception Island where we spent a beautiful Saturday visiting the island. The Spanish base Gabriel de Castilla saw the LMG enter the island and invited us to stop, which we did and enjoyed their hospitality. We then left for Palmer Station, arriving Sunday morning at 0800 on schedule. After dinner on station, we presented a series of slide shows that were well received.

We departed Palmer Station this morning at 1000 and headed north through Neumeyer Channel and Schollaert Channel to Dallman Bay, where many humpback and orcas observed. Obtained a short sonobuoy recording of orca calls. We are now crossing the shelf enroute to the Drake Passage.

We feel very fortunate that no one was hurt when the winch was pulled off its stand. Inspection showed that one of the eight locking clips was missing and two on the back side were of the wrong design. The bottom plate is relatively thin, so the bolts only had about 1 inch or less of thread in the bottom. Given the tension on the wire, it is not surprising that the back bolts striped the threads. I think this was an accident waiting to happen, and thanks to the MPC and crew, the main and 01 decks were locked down during the dragging operations and no one was on deck to be hurt. Captain Robert indicated that the winch should be fixed and operational for the next cruise.

One secondary objective of this cruise was to visit the SO GLOBEC automated weather stations (AWSs) deployed on Kirkwood and Dismal Islands in Marguerite Bay. Given the need to head north early to go get S1A before reaching Palmer Station, there was simply not enough time to inspect the AWSs.

Bob Beardsley

Chief Scientist