2 Jan 1974
- waterbody:North Atlantic OceanGrand Turk Island; U.S. Naval Facility
NOTES: Notes on tape: "Time: 0300 Zulu 3Jan73. [Equivalent to 2200 2Jan74; the year stated on tape is incorrect.] [MLNS notes: low level thumps throughout, with several louder trains - at 6:15, 7:41, 16:38, 24:45, 25:29. All sound like doublets - 08Dec2003 CB] Notes from analysis log: "Cassette number side up - rewind. Ambient level low. Distant ship traffic heard off and on thru out tape. Humpback: Neg.; Minke: Pos.; No. Heard: [blank]; No. Trains: 5+; Need for further analysis: Yes (good level types). Notes: Starting at 220 is a fair level thump train, again at 254 is a stronger and longer train. At 428, hear bits of Minke thumps, - at 448 starts a train of them, moderate level. Again at 470 only this time better level longer duration, at 631 is a good loud level. At 713 is a distant ship twin turbine (gear) throbs showing stronger."
[Notes from analysis log for all tapes in the GRANDTURKS series: "Six half-hour background recording samples on selected days for a period of 53 days... to detect the arrival and departure of the Humpback whales (via sounds) for the season in the Caribbean Sea, Mouchier, Navidad and Silver Banks...There are indications that recordings used a 420Hz Low Pass Filter. Recording equipment used was a Realistic model CTR-19. Cassette recorder operating on 110VAC, Freq 60-10,000Ha.. The Realistic recorder is poor recording frequencies below 60Hz as evidenced by spec sheet and sonograms. There is 120 & 180Hz electrical interference 'splatter' on some tapes. In certain cases when the ambient is low, the gain of the systems are raised hence we have heavy interference masking wanted signals. This could be caused by a fluorescent light fixture near the recording system? I doubt that it is in the hydrophone pre-amp network." See analysis log for more details.] SEAOCEAN