DATE: 14Nov98 IN PREP FOR: Antarctic Journal 1998 REFERENCE AS: Baker, K.S., W.A.Kozlowski, M.Vernet, J.L.Jones, L.B.Quetin, R.M.Ross, R.C.Smith and W.R.Fraser, Palmer LTER: Annual season November 1997-March 1998, Antarct. J. U. S. 1998. Palmer LTER: Annual Season Sampling at Palmer Station November 1997-March 1998 Karen S. Baker, Wendy A. Kozlowski, Maria Vernet Marine Research Division Scripps Institution of Oceanography University of California at San Diego La Jolla, CA. 92093 Janice L. Jones, Langdon B. Quetin, Robin M. Ross, Raymond C. Smith Institute for Computational Earth System Science and Marine Science Institute University of California at Santa Barbara Santa Barbara, CA. 93106 William R. Fraser Polar Oceans Research Group Biology Department Montana State University Bozeman, Montana 59717 The Palmer Long-Term Ecological Research (LTER) Program (Smith et al., 1995) completed a seventh season of sampling at Palmer Station. The Palmer LTER sampling strategy combines seasonal time series data from the nearshore Palmer grid and seabird observations from nesting sites near Palmer Station with annual cruises which cover a regional grid along the western Antarctic Peninsula The LTER January cruises (LMGR98-08 aboard the Abel-J and LMG98-01) visited the Palmer Basin inshore stations twice in order to provide continuity in the seasonal record (this issue). The original station sampling plan (Baker et al, 1996) as modified for the 1997/98 Palmer field season is given in Table 1 which gives the season's sampling overview in terms of the standard week defined previously (Baker et al, 1996; Baker et al, 1997). Significant dates include arrival of research teams at Palmer (30 September and 13 November 1997), first bird observations (01 October 1997), first chlorophyll sample (19 November 1997), first zodiac profiling cast (25 November 1997), first acoustic transect (04 December 1997), start of cruise (18 January 1998), end of cruise (13 February 1998), last profiling cast (10 March 1998), acoustic transect (10 March 1998), and last LTER bird observation (04 April 1998) at Palmer Station. In Table 1 each line summarizes one cycle of standard sampling. The initial event number, month begin, day begin, day end, and year are given in the first five columns. The sixth column summarizes the types of standard days included in this particular cycle. Acoustic transects, hydrographic and optical profiling, phytoplankton sampling, targeted krill tows for physiological condition and instantaneous growth rate experiments are given in the next columns followed by general comments. There were some changes from past seasons in the sampling program. With six LTER personnel for the 1997- 1998 season (2.0/S016; 1.5/S032; 1.5/S028; 1.0/S035), the daily sampling week included sampling 4 stations instead of 9 for weekly profiling hydro-bio-optics, 2 stations twice weekly instead of 4 for phytoplankton sampling, growth experiments every 2 weeks instead of weekly, sampling for condition factor of young of the year only and eliminating standard zooplankton tows. Further, nutrient samples were shipped to the University of California Santa Barbara Analytic Facility for analysis. At Palmer new digital detectors replaced old analog sensors for nutrient hardware and Alpkem EnviroFLow version 2.1 software was purchased. The hardware and software for HPLC analysis remained the same as last year. This season the satellite network link with LES9 provided two blocks of approximately 5 hours of online time per day making possible FTP file transfer of data and real-time electronic talk communication. The ability to transfer data daily allowed us both to conduct real-time data analysis at the home institutions and to archive the data in a timely and efficient manner. In addition to standard chlorophyll samples run in replicate for the greater than 0.45 Mm phytoplankton at selected depths, the <20 Mm fraction was sampled at the 50% light level (ranging from 3.0 m to 12 m). Hydrographic profiles were also run as requested at station Janus (D.Karentz, S007, personal communication) and at the pier (T.Amos, personal communication). Concurrent deployments last year with the stations STD instrument will permit intercomparison studies. During the 9798 USAP season, ice conditions changed in September when the fast ice blew out of Arthur Harbor and was replaced a few days later by pack ice which remained until ice break up in November. Ice was broken up in Arthur Harbor by the ship arriving 13 November 97. Ice had cleared from the Palmer basin by 25 November when the first zodiac work began. Zodiac operations were simplified since they were not limited by brash ice this season. This spring/summer was preceded by an above average winter of ice similar to that of 9596 when pack ice did not begin to clear from the nearshore Palmer region until November 1995. Preliminary data show seasonal progression in selected parameters through the spring and summer (Figure 1), providing an overview of the season. The 9798 season showed low chlorophyll biomass November through December with surface phytoplankton blooms of 2-5 mg/m3 in January at stations B and E. Between November 22 and March 21, 11 acoustic transects were run from stations A to E (Figure 1c) and 9 from F to J. Krill collected from target tows were measured for length frequency distributions throughout the season. This season the few salps observed were post cruise from the zodiac at the surface. Reproductive events associated with breeding chronology of Adelie penguins on Humble Island this season (Fraser et al., in press) are noted by arrows in Figure 1c. The Adelie penguin breeding population size, a measure of winter survival, decreased by 3.6% relative to the past season while the per-pair breeding success of these penguins was 1.58 chicks creched per pair representing an increase of 7.0% relative to the 1996-97 season. The increase in breeding success of 0.11 chicks per pair may in part reflect a lack of tick infestations early in the season. The breeding chronology and mean fledging weights were unchanged from last year. The LTER seasonal observations of the marine environment, the lower-trophic level abundance and distributions for the area, and the seabird observations at nesting sites near Palmer were recorded from November 1997 to March 1998. The sampling event log, participant list and other project information for the season are available online (http://www.icess.ucsb.edu/lter). Acknowledgement and thanks are given to members of the Palmer LTER research team and of Antarctic Support Associates. This material is based upon work supported by the National Science Foundation under Award No. OPP-9632763 with additional funding provided by the Regents at the University of California. Palmer LTER Contribution No. xx. References Smith, R.C., J.L. Jones, L.B. Quetin, R.M.Ross, K.S. Baker, W.A. Kozlowski, M. Vernet, and W.R. Fraser. 1996. Palmer LTER: Annual Season Sampling on Station. Antarctic Journal of the U.S., 31(2), 164-166. Baker, K.S., M. Vernet, W.A. Kozlowski, J.L. Jones, L.B. Quetin, R.M. Ross, Raymond C. Smith and W.R. Fraser. 1997. Palmer LTER: Annual Season October 1996-March 1997. Antarctic Journal of the U.S. (accepted). Fraser, W., D. Patterson, E. Holm, K. Carney and J. Carlson (in press) Seabird research undertaken as part of the NMFS/AMLR ecosystem monitoring program at Palmer Station, 1997/98 in AMLR 1997/98 Field Season Report: Objectives, Accomplishments and Tentative Conclusions. J.Martin (ed). Southwest Fisheries Science Center. Smith, R.C., K.S. Baker, W.R. Fraser, E.E. Hofmann, D.M. Karl, J.M. Klinck, L.B. Quetin, B.B. Prezelin, R.M. Ross, W.Z. Trivelpiece, and M. Vernet. 1995. The Palmer LTER: A long-term ecological research program at Palmer Station, Antarctica. Oceanography. 8(3), 77-96. Karl, D.M., L.B. Quetin, and K.S. Baker. (this issue) Palmer LTER: Annual January Cruise for 1998 (AbelJ98-01; LMG98-01). Antarctic Journal of the U.S.. Figure Legends Figure 1a: Air temperature [degrees C] (heavy line) and water temperature [degrees C] (dashed line) at Palmer Station for the 9798 season. Figure 1b: Surface chlorophyll [mg/m3] (filled diamonds), nitrate [MM] (open squares), and silicate [MM] (filled squares) at Station E for the 9798 season. Figure 1c: Adelie penguin foraging [hours] (filled squares). Arrows indicate day of first egg laying, first brood, first creche, first fledging, and peak fledging at Humble Island for the 9798 season. Table Legend Table 1: Palmer LTER Event Log Overview of 1997/1998 season by sampling week (see Table 1a, for definition of standard sampling week). Events include acoustics (bio-ac, Biosonics 120KHz), discrete sample for chlorophyll analysis (chl), conductivity-temperature-depth (ctd, Seabird), high performance liquid chromotography of phytoplankton pigments (hplc), instantaneous growth rate (igr), targeted tow for krill (krilltarg, 50KHz), microscopic analysis of net plankton (net, >5Mm), inorganic nutrient analysis (nuts), photosynthetically active radiation (par), physiological condition larvae (phycon), microscopic analysis of pico- plankton (pico, 0.5-5.0Mm), particulate organic carbon (poc), production photosynthesis vs irradiance (Ppi), primary production simulated-in-situ (Psis), profiling radiometer (prr, BSI), discrete sample for salinity analysis (sal), transparent exopolymer particles (tep). and standard zooplankton tows (trwl).