Date: Tue, 30 Jan 2001 14:26:15 -0300 To: mo-sciweekly@polar.org, mpc@lmg.polar.org, verretro@lmg.polar.org, alsuther@nsf.gov, kerb@nsf.gov, ppenhale@nsf.gov cc: Menzies Dave <menzieda@lmg.polar.org>, Carrillo Christopher <carrilch@lmg.polar.org>, Chapman Erik <chapmaer@lmg.polar.org>, Ireson Kirk <IresonKi@palmer.usap.nsf.gov>, Kozlowski Wendy <kozlowwe@palmer.usap.nsf.gov>, Ross Robin <rossro@palmer.usap.nsf.gov> From: "Ross,Robin" <rossro@palmer.usap.nsf.gov> Subject: LMG01-01 21-27 January Palmer LTER cruise LMG01-01 2001 January LTER cruise: 21-27 January synopsis The last week of the annual Palmer LTER cruise (LMG01-01) included 5 days of science operations, 1 day of cargo operations at Palmer Station and 1 day of the northbound crossing of Drake Passage. The LM Gould is expected to dock in Punta Arenas at 0800 January 31, 2001. During this period our scientific activities were diverse. We completed the stations on the last of our five cardinal lines, the 200.* transect which ends at the mouth of Marguerite Bay just south of Adelaide Island. The inner stations of this line were characterized by high phytoplankton concentrations and a scarcity of Antarctic krill and salps relative to the other 4 cardinal lines. On January 21, we put a party of 4 ashore on Avian Island to sample the diets of the Adelie penguins nesting there. The diet samples showed much greater diversity than those from Adelie penguins nesting near Palmer Station, with fish and amphipods common in addition to two species of euphausiids. A zooplankton tow in the basin east of Avian Island reflected the same diversity. On 22 January we called at Rothera and continued our collaborative work with the marine science group from the British Antarctic Survey. In the morning 17 BAS personnel, including most of the marine science group, boarded the ship, and 10 LTER scientists and Raytheon support personnel went ashore. On board the LM Gould we conducted a short series of CTD casts to investigate the oceanic link between the site of the BAS seasonal sampling in Ryder Bay and the southern end of the Palmer LTER study region. The CTD casts included one with the two CTDs from the BAS seasonal sampling strapped onto the rosette in order to cross calibrate our systems. We also exchanged samples for bacterial abundance from flow cytometry and DIC from a full vertical profile from the furthest CTD cast. A comparison of the seasonal cycles as documented at the stations near Palmer Stations and at Ryder Bay near Rothera is one of the goal of this collaborative effort. The two seasonal studies are located at the northern and southern reaches of the Palmer LTER summer study region, and we expect to gain some understanding of the mechanisms driving the seasonal cycles from this comparison. In the early evening we gave tours of the ship, and BAS personnel gave tours of the facilities at Rothera. A social exchange continued at Rothera until our departure at 2300. During our transit from the 200.* cardinal line back to Palmer Basin, those on board the LM Gould who had defied the wrath of King Neptune by crossing the Antarctic Circle without his permission were called to account for their transgressions. The inductees entertained the King and his court with a series of skits, and then were cleansed of their sins during a formal ceremony. King Neptune left satisfied that the 20 who had crossed without permission had been suitably chastised. The last day of sampling was in the foraging area of the Adelie penguins nesting near Palmer Station. We first occupied stations B and E of the nearshore sampling stations. Our normal activities were modified due to the loss of ship time, but good visibility during the day allowed us to conduct observations of both seabird abundance and activity and acoustic biomass and distribution on both the 3.7 km and 10 km picket lines. The picket lines are semi-circular transect lines at 3.7 km and 10 km from the Adelie penguin rookeries near Palmer Station. We also were able to partially complete a seabird and acoustic survey of the high density grid established in the foraging area. Simultaneous seabird and acoustic observations were collected over a 10 km by 20 km grid, with transects planned to be 2.5 km apart. Surface samples of chlorophyll a and nutrients were also taken, and both xbts and xctds deployed to describe the basic hydrographic characteristics of the region. About half of the standard grid was completed with both seabird and acoustics before we had to dock. The picket lines and high density grid were established to link the Adelie penguins nesting near Palmer Station with their surrounding marine resources. The results will be integrated with ongoing studies of foraging duration and reproductive success of these penguins conducted on station by B. Fraser, one of the Palmer LTER PIs. The support we have received from both Raytheon personnel and the ECO bridge and crew of the LM Gould has been integral to the productivity of this cruise. We would like to thank everyone concerned for their interest in the science and their willingness and ability to meet the needs of the cruise. Regards, Robin Ross for the Palmer LTER