PALMER STATION SCIENCE SITREP March 1995 S-013 LONG-TERM ECOLOGICAL RESEARCH (LTER) ON THE ANTARCTIC MARINE ECOSYSTEM: AN ICE-DOMINATED ENVIRONMENT (SEABIRD COMPONENT). William R. Fraser and Wayne Z. Trivelpiece, Montana State University, Bozeman, MT. SEABIRD INVESTIGATIONS AT PALMER STATION AS PART OF THE NMFS/AMLR ECOSYSTEM MONITORING PROGRAM. William R. Fraser, Montana State University, Bozeman, MT. THE IMPACTS OF TOURISM ON ADELIE PENGUIN POPULATIONS AT PALMER STATION. William R. Fraser, Montana State University, Bozeman, MT. PERSONNEL ON STATION: Eric Holm, Bill Fraser and Donna Patterson. Season objectives and results for the above stated programs have been summarized in past reports. Due to the complete reproductive failure of South Polar Skuas, our field work did not require the anticipated time extention to 6 April. Personnel on station thus departed Palmer on 24 March. Season-end activities focused on completion of this season's component of the long-term Giant Petrel banding program and marine mammal census. The former (350 chicks banded) continues to suggest that populations of this species are currently stable in the Palmer Station area. This is a unique situation, as Giant Petrels are exhibiting a marked decrease in numbers throughout much of their range due to the possible effects of incidental mortality resulting from long-line fishing. As in past seasons, birds with embedded long-line hooks were again observed at Palmer Station (2 cases). This form of entanglement will be reported to the appropriate CCAMLR groups through the U.S. AMLR program. Although analysis of our most recent marine mammal census is currently incomplete, preliminary results suggest a 75% reduction in the fur seal population this season when compared to past years. This reduction in numbers is not likely due to mortality, but rather follows a season-long trend of a coincident, measurable paucity in krill availability as described in past reports. This season, as compared to past ones, krill exhibited little or no inshore presence during March, the factor that seems to attract fur seals to the Palmer Station area. Fur seal diets also exhibited a marked increase in the presence of fish, which has not been observed in the area in past seasons. Although this krill shortage was predicted based on past data, the magnitude of its effects has provided extremely interesting information on food web interactions in the AMLR/LTER study area. S-013 completed its field work by collecting plant specimens for S-003, as this group was unable to finish its work during its brief visit to Palmer in February. These specimens are currently on their way to S-003's laboratories through the courtesy of Mr. Glen Smith, ASA Laboratory Manager, who is hand-carrying them to the U.S. This is S-013's last report for the 94-95 season. Access to nearby islands continued to be good during February, allowing us to complete diet and telemetry (foraging trip duration) studies on Adelie Penguins, and complete our work on the species' reproductive success. Final results of our diet work suggest that the availability of Euphausia superba was low early in the season, but subsequently improved throughout the month of February. Three lines of evidence support this conclusion. First, another euphausiid, Thysanoesa macrura, which represented up to 40% or more of the stomach contents by weight early in the season, dropped out of the diet completely, leaving Euphausia superba as the dominant (100% of the samples by weight) dietary component. Second, foraging trip durations, which averaged 30 hours each early in the season, were averaging 8-10 hours by early February. Third, the freshness of stomach contents (i.e. E. superba) improved considerably through mid- February when the final samples were obtained, suggesting the resource was relatively close to the colonies. Although krill availability improved later in the season, Adelie Penguin chicks nevertheless fledged at significantly lower weights than in past seasons (e.g. averaging 2950 gm vs. 3200 in past years), suggesting that early season food shortages did have an effect on normal chick growth and development. The season was thus characterized by high reproductive success (1.30-1.54 chicks creched per pair), but significantly lower fledging weights. Tourist visits to Torgersen Island ended on 26 February with the departure of the season's last scheduled vessel. At this writing, approximately 560 people visited the island's colonies. The reproductive success of Adelie Penguins located in areas on Torgersen Island open to tourism and in control sites without tourist access exhibited no differences relative to each other (1.35 and 1.44 chicks creched per pair, respectively), or to the Palmer area as a whole (1.4 chicks creched per pair). Data to look at specific, egg and/or chick loss rates at tourist and control sites, however, have not yet been examined for patterns. Final results of a new, experimantal marking system being tested as a substitute for flipper bands on Adelie Penguins have been positive. The system, used primarily by fisheries biologists, involves thin plastic tags that are anchored subcutaneously. Results to date suggest the tags are more visible than conventional bands and thus greatly improve the probabilities of finding all the marked birds in a population. Tagged birds, for example, were seen by independent observers at almost twice the rate as flipper banded birds in controlled experiments where the total number of marked birds was known. Moreover, no evidence of tissue damage, inflamation or infection was detected among tagged birds. One problem, not detected until later in the season, was that tag retention rates were slightly lower than band retention rates. These losses were all confined to tags placed at sites level with the shoulders, a common "striking" point in aggressive. S-016 LONG-TERM ECOLOGICAL RESEARCH ON THE ANTARCTIC MARINE ECOSYSTEM: AN ICE-DOMINATED ENVIRONMENT (PHYTOPLANKTON COMPONENT). Maria Vernet, Scripps Institution of Oceanography. Personnel on station: John Harrison, Ted Ruel and Wendy Kozlowski The final month of the 94-95 LTER season began with a sampling run on the second of March. Due to technical dificulties with both the light meter and then later the winch, we were only able to collect a full profile at station B and surface water at station C. There were plans to go out again later that week to complete the transect, but mother nature did not allow it, and the R/Z Maria platform was pulled from the boat on the fifth. From the water collected on the second, it appears that the bloom that had occured off of Bonaparte Point during the last few weeks of February had ended. The remaining days on station were spent finishing up nutrient sample analysis from the cruise (yes John, you are finally done!) and inventory and packing of the labs for the next season. The Hitachi HPLC system was packed for transport back to UCSD for maintenance/repair and use in processing the last of the pigment samples. We would like to thank all personnel on station for the help and good times this season. We look forward to another succesful summer in 95-96. S-028 LONG-TERM ECOLOGICAL RESEARCH ON THE ANTARCTIC MARINE ECOSYSTEM: AN ICE-DOMINATED SYSTEM. Robin M. Ross and Langdon B. Quetin, University of California, Marine Science Institute, Santa Barbara, California 93106. Personnel on station: Karen Haberman, Janice Jones (split position with S-032), Arnold Ammann, Tim Miller An acoustics run from A-E was completed on 2/27. Weather prevented sampling on 2/28 and 3/01. ROZE was pulled from the water and dismantled on 3/02 in order to have all retrograde ready for the 3/03 cargo deadline. An attempt was made to complete one last set of standard tows of 3/06 but a series of snow squalls moved into the area so we packed the gear and completed the S028 station inventory (in milvan #704 and the LTER unheated milvan). Weather also prevented any further krill searches. Janice Jones and Arnold Ammann departed Palmer Station on the R/V POLAR DUKE on March 9, 1995, leaving Karen and Tim to continue ingestion rate and selectivity experiments by krill on phytoplankton. Experiments were conducted using both field- collected and lab-cultured phytoplankton. Water samples from the experiments were analyzed using HPLC, fluorometry and cell counts, with additional samples taken for chemical analysis. Unfortunately, experiments to compare growth of krill fed colonial Phaeocystis vs. those fed diatoms could not be done, due to lack of colonies in the Phaeocystis cultures. The field team portion of S-028 wishes to express its appreciation to the personnel of Palmer Station and the R/V POLAR DUKE for making this a productive and enjoyable season for all. S-032 LONG-TERM ECOLOGICAL RESEARCH (LTER) ON THE ANTARCTIC MARINE ECOSYSTEM: AN ICE DOMINATED ENVIRONMENT. Ray Smith, University of California at Santa Barbara. Personnel on Station: Janice Jones (split position with S-028), Jens Sorensen, Brady Seely There was no verification CTD cast done for Tony Amos at Palmer Station's dock for the month of March. A sampling run from B-E was attempted on 2/27, but due to radio malfunctions and equipment problems for S016, the B-E portion was abandoned and F-J was done. Weather prevented further sampling and ROZE was pulled from the water and dismantled on 3/02 in order to ensure all retro was packed and ready to go for the 3/03 cargo deadline. The 2 weather days (2/28 and 3/01) were spent doing inventory and dismantling the lab. A complete inventory of everything S032 has on station (stored in milvan #704 and in the heated milvan) has been completed. Thank you to all station personnel for a very successful and most enjoyable sampling season. S-036 ADAPTATIONS TO COUNTER DIFFUSIONAL CONSTRAINTS IN MUSCLE OF CHANNICHTHYID ICEFISHES. Bruce Sidell, University of Maine, Orono, Maine. PERSONNEL ON-STATION: Bruce Sidell, William Riemenschneider. Trawling operations for fish capture to support our project were carried out aboard R/V Polar Duke on 21-22 March after a brief port call at Palmer Station on 21 March to disembark a passenger needing medical attention. The site of trawling activities was Dallman Bay off the south short of Brabant Island in the vicinity of Astrolabe Needle. Fishing was carried out in conjunction with project S-037. An 18ft Otter trawl was deployed for approximately 17 tows over a 15 hr period and yielded approximately 40 icefishes (Channichthyidae; dominated by Chaenocephalus aceratus, with approximately 15 Chionodraco rastrospinosus, 5 Champsocephalus gunnari and one Pseudochaenichthys georgianus), 120 G. gibberifrons, 25 Notothenia coriiceps, one Dissostichus mawsoni and one specimen of Bathyraja. Animals were transported back to Palmer Station and transferred to the station's aquarium on 22 March. Setup of functional laboratory was accomplished within 3 days. Initial work has focused upon fixation of heart ventricle and oxidative skeletal muscles from channichthyid icefish species that do express the intracellular hemoprotein, myoglobin, in heart (Chionodraco rastrospinosus) or that do not express this oxygen carrying pigment (Chaenocephalus aceratus). These tissues will be transported back to our CONUS laboratory for subsequent quantitative electron microscopy studies. Prior to commencing this work, a protocol for perfusion fixation of heart ventricle was finalized. Additional tissues have been harvested and frozen in liquid nitrogen for subsequent assays of key enzymes of intermediary metabolism and for extraction of nucleic acids (RNA, DNA). Preliminary preparations of substrates for some enzymatic determinations have been completed. In April (PD 95-3) three additional members of our field team will join us at Palmer for the balance of our field season. In addition to extending the work described above, we will initiate experiments with isolated perfused hearts from Channichthyid icefishes to evaluate whether myoglobin expression affects the mechanical performance of the hearts, we will devote significant effort to preparing isolated nuclei from heart muscle of these species for subsequent assays of Mb gene expression and we will establish techniques for the measurement of fatty acyl synthase in oxidative muscle tissues (a key enzyme in the process of modifying fatty acids for subsequent metabolism in the tissues). This work is being carried out with excellent support from both staff at Palmer Station and the master and crew of R/V Polar Duke. We gratefully acknowledge their contributions to the success of our project. S-037 ASSEMBLY AND STABILITY OF MICROTUBULES FROM ANTARCTIC FISH AT LOW TEMPERATURES. H. William Detrich, Northeastern University, Boston, MA. Project S-037's 1995 field season began with the arrival of advance team members S. Parker, K. Malloy, and E. Cocca at Palmer Station on 6 March (R/V Polar Duke Shuttle #2). En route, successful fishing operations were conducted at the East Dallmann Bay MSSSI 36, resulting in the capture of approximately 60 icefish (Chaenocephalus aceratus, Champsocephalus gunnari, and Chionodraco rastrospinosus), 100 humped rockcod (Gobionotothen gibberifrons), and 10 yellowbelly rockcod (Notothenia coriiceps). Unfortunately, one set of trawl gear (18-ft net and doors) was lost on the last scheduled tow due to parting of the winch cable. Laboratory setup was accomplished in four days, after which experiments were initiated by S. Parker and E. Cocca to isolate nucleic acids (genomic DNA from testes, total RNA from various tissues) and microtubule proteins (brain and erythrocyte tubulins and microtubule-associated proteins) from these fish species. K. Malloy (S-037/SGER) began whole-animal and cell-culture studies to examine the kinetics of UV-mediated DNA damage and repair in C. aceratus. This work includes analysis of the relative contributions of light- and dark-repair systems and preparation of nucleic acids from UV-irradiated specimens for subsequent cloning of the genes for repair system components. Tissues (brains, testes, head kidney, spleen, etc.) were also collected and frozen for retrograde to our CONUS laboratory. S-037 main body (H. Detrich, A. Frankfurter, A. Ramsey, and M. Rutberg) arrived at Palmer Station on 21 March (R/V Polar Duke cruise 95-2A). A short fishing trip to East Dallmann Bay (21-22 March) yielded fish species in numbers similar to those given above. In addition, one specimen each of the icefish Pseudochaenichthys georgianus, an Antarctic toothfish of the genus Dissostichus (species mawsoni?), and a Bathyraja species were captured. At Palmer, H. Detrich and A. Ramsey began isolating and characterizing the microtubule-associated motors dynein and kinesin from N. coriiceps and G. gibberifrons, respectively. Using N. coriiceps microtubules, A. Frankfurter has initiated the separation of neural tubulin isotypes for analysis of their functional and structural properties. M. Rutberg is culturing epithelial and neural cells from C. aceratus and N. coriiceps for study of their microtubule cytoskeletons by immunofluorescence microscopy. Parker, Malloy, and Cocca continue the projects that they began earlier in the month. During April and May we will continue these lines of investigation. We thank the personnel of Antarctic Support Associates and the captain and crew of the R/V Polar Duke for their excellent support of our field and laboratory research programs. S-038 FORAGING ECOLOGY AND REPRODUCTIVE ENERGETICS OF ANTARCTIC PETRELS. Wesley W. Weathers. University of California, Davis, CA. PERSONNEL ON STATION: Wes Weathers, Dan Osborn Most of this project's research is being conducted at Davis Station in east Antarctica. Our two principal research goals for Palmer Station were: 1) to validate the doubly labeled water (DLW) technique for measuring CO2 production using Wilson's Storm Petrel chicks (Oceanites oceanicus) and 2) to determine the energy equivalent of CO2 production based on simultaneous meas- urements of O2 consumption and CO2 production of petrel chicks in an open-circuit respirometry system. Validating the DLW technique entailed simultaneously measuring CO2 production by DLW and the Haldane technique over a 24-h period. This was done with 10 Wilson's Storm Petrel chicks that ranged from 21-50 days of age and 44.2 to 64.3 g mass. Chicks normally fledge at 60 d age, hence the chicks varied between 35- 83% of fledging age. Prior to both types of experiments, chicks were tube-fed either a 50:50 mixture of homogenized krill and fish oil or homogenized krill alone. For the validation studies, chicks were fed 5.4 +/- 2.3 g (mean +/- SD, n=9) of 50:50 homogenized krill:fish oil or 8.9-10.0 g of homogenized krill. Prior to RQ determinations, chicks received 6.5 +/- 1.9 g of the krill-fish oil diet. Most chicks lost weight on this quantity of food and all chicks lost mass during their 1-4 day period in captivity. For chicks receiving the krill-fish oil diet, the amount of weight lost was inversely related to the amount of food consumed and is described by the relation: Y = -12.8 + 67.9 X; where Y is % body mass lost per day and X is g diet fed per day per g chick. This relation predicts that a 50 g chick would need to receive 9.4 g of diet per day to maintain its mass. The mean respiratory quotient (RQ = vol CO2/vol O2) of 6 chicks feed the krill-fish oil diet artificial diets was 0.71 +/- 0.008 (range 0.700 to 0.722), not significantly different from the RQ of 0.713 predicted from the protein and fat content of their diet. The RQs of two chicks feed homogenized krill (high protein, low fat diet) were 0.727 and 0.734. The expected value is 0.73. Because most chicks failed to grow on the amounts of food provided, we did not detect evidence of CO2 production associated with protein deposition. Data of the validation of the DLW method are unavailable, pending analysis of stable iso- tope levels in the obtained blood samples. S-091 PALMER IRIS SEISMOLOGY. R. Butler/G. Holcomb, U.S. Geological Survey, Albuquerque, NM. No personnel were on station. The system has been operated by the station science technician. On 08 March the North/South and East/West instruments were evacuated to restore normal vacuum. S-106 VERY LOW FREQUENCY (VLF) REMOTE SENSING OF THUNDERSTORM AND RADIATION BELT COUPLING TO THE IONOSPHERE. U. Inan, Stanford University. No personnel were on station. The system has been operated by the station science technician. Bill Trabucco completed the annual calibration and maintenance of the VLF antenna system. S-254 CHLORINE- AND BROMINE-CONTAINING TRACE GASES IN ANTARCTICA. R.A. Rasmussen, Oregon Graduate Institute for Science and Technology. There are no personnel on station. A total of 12 air samples were collected in stainless steel canisters, behind the clean air facility by the station physician for the month of March. Bob Dalluge was contacted and up dated on the current canister inventory. S-257C COLLECTION OF ATMOSPHERIC AIR FOR THE NOAA/CMDL WORLDWIDE FLASK SAMPLING NETWORK. James T. Peterson, Palmer Station, Environmental Research Laboratories, National Oceanic and Atmospheric Administration. There are no personnel on station. A total of 8 air samples were collected in glass flasks from a site near the foot of the glacier for the month of March. No problems were noted during the sampling. S-275 UM/DOE-EML REMOTE ATMOSPHERIC MEASUREMENTS PROGRAM. J. Prospero/T. Snowdon, University of Miami; C. Sanderson/N. Chui, EML/DOE N.Y. No personnel were on station. The system has been operated by the station science technician. One sample filter was exposed for the duration of each week, and a weekly schedule of calibration, background, and sample counts was maintained. On 01 March the background filter was accidentally used in place of the calibration material. This was discovered at the end of the calibration count on 03 March. On 27 March, by request of the P.I., the hoses and pump were inspected for possible air leaks. No leaks were found. T-312 TERASCAN SATELLITE IMAGING SYSTEM. R. Whritner, Scripps Institute of Oceanography, La Jolla, CA. Personnel on station: Burt Baker and Jim Hamlin The system has been operated by the station science technician. The TeraScan system collected, archived, and processed DMSP and NOAA telemetry, maintaining a schedule of 15 passes per day. AWS data was collected from the Bonaparte Point and Hugo Island automatic weather stations in support of the LTER project. On 08 March the TeraScan Sun workstation halted itself, resulting in the loss of data from four scheduled satellite passes. No cause was found, and the system rebooted normally. On 10 March the TeraScan scheduling software inexplicably failed to capture data from 14 scheduled late-night satellite passes. Scheduling was reset, and data from two passes was captured. On 23 March, the scheduling software failed to catch 9 late-night satellite passes. No cause has been found. On 24 March the workstation halted itself. The station science technician performed a soft reboot and restored the system to normal operation. Later the same day the system was found in unresponsive state, and the science technician performed a hard reboot to restore normal operation. No cause for the failure has been found. T-313 UV MONITORING EXPERIMENT. C. Booth, Biospherical Instruments, Inc. No personnel were on station The system has been operated by the science technician. Throughout the month, raw irradiance data were collected daily and transmitted to BSI. Preliminary irradiance data and inferred ozone abundances were produced in support of Science. The 0900 UT and 0000 UT data scans were removed due to increasing sun angle. An absolute calibration was performed using the seasoned lamp. Tim Lucas from Biospherical Inc. completed the annual maintenance and calibration of the UV monitoring system. 03153801.764 PLM172.APR