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S Ship Direction R.V. JORDAN: EASTROPAC SMITHSONIAN INSTITUTION DIVISION OF BIRDS AT SEA DAILY LOG - E SPECIMEN or OBSERVERS: Harrington Date 19 October Pg.# 1 TIME SPECIES # DIR. BAND NO. REMARKS 0654 0725 0745 0803 Leach Pet 1 SE 0817 1 SE 0828 Cook Pet? 1 SE not seen well(distant) - appeared very light, uniform dark color 0832 Leach Pet 1 SE 0835 Harcourt Pet 1 0835 Storm Pet 1 distant. 0920 Leach's P. 5 1006 1 1015 2 1027 1045 Leach P 5 1100 1200 1223 Leach P? 1 SE 1240 Storm Pet? 1 SW 1248 P. cookii 1 1316 WRSP 2 1327 Leach's? 1 SE 1331 Storm Pet 2 SE 1347 Pom. Jaeger 1 SE 1400 1430 P. cookii 1 Leach's 1 3 1447 Leach's 1 1510 WRSP 5 1528 1 1540 Storm Pet? 1 1542 Leach's 1 SE 1613 1 SE 1615 1710 1712 WRSP 1 SE 1715 Leach's 1 SE 1723 " 2 SKY 100% clear; wind NW 12 KNTS; sea 1, Swell SE 6', mom full, Barom 30.00 (=1015) SUNRISE, BEGIN OBS. Close observations resume ½ dark rump " " well seen: flight like beach, no black divid. Line, broad white rump, slightly notched tail. Feet not extending sitting on H2O, all dark rump very white rump, deep fork tail, dividing line seen a few small fish (Coast#) jumping. Looked like tuna on H2O; 2 w/light rump, 3 w/dark CLOSE OBSERVATIONS Resume " light rump Booted small, very pronounced large white rump. Flight was almost swift or swallow-like. Wings appeared narrow. NOT A GOOD LOOK - poor light 100 yards well seen, sitting on H2O, flushed to SE. Stiff wingbeats dark rump. distant light phase weather: same as this AM. Wind 9 knots NW Sky 30% thin stratus. Barom. 29.9 on H2O, fairly well seen. on H2O, black div. line seen " distant black dividing line seen. small white rump close obs. Resume " dividing line seen white rump, black dividing line seen, molt? in primaries. SI-MNH-958-e Rev. 5-66
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S Ship Direction R.V. JORDAN: EASTROPAC SMITHSONIAN INSTITUTION DIVISION OF BIRDS AT SEA DAILY LOG - E SPECIMEN or BAND NO. REMARKS OBSERVERS: Harrington Date 21 october 1967 Pg.# 1 TIME SPECIES # DIR. 0600 Small pterod. Aeen 0645 Underway heading south 0656 Sunrise, BEGIN OBS. 0710 Leach's ? 1 SE 0718 Storm Pet 1 [illegible] 0730 0745 0808 Hatoounter WILWASP 1 W all white rump, tail notch not seen well 0815 WRSP 1 [illegible] 0835 WRSP 1 [illegible] 0925 Leach's 1 [illegible] WRSP 1 [illegible] 0942 WRSP 1 [illegible] 1016 Storm Pet 1 W 1025 WRSP 1 [illegible] 1030 CLOSE OBSERVATIONS; WEATHER: 90% altostratus Cover Wind 15 [illegible], wet Temp: 76.3, Dry Temp: 83.0, Sea Temp: 26.8, Salin: 34.64 Thermal depth: 40 to 125 : Weather 1 wave period ngt: cloud typ 7 Swell dir: Swell period: Barom 1245 RFTB 1 1255 WRSP 2 [illegible] 1317 Leach's 1 [illegible] 1405 1410 BF B 1 1420 WRSP 2 [illegible] 1435 Com. or Arctic Teem 1 S imm 1437 WRSP 1 [illegible] 1505 Wilson or Hanc. 1 W seen fairly well, no black dividing line. "" "" "" no feet seen ext. beyond tail. imm, close, that legs, that did been well. 1522 Arctic T 1 [illegible] 1535 1550 Wils/Hanc. 1 [illegible] 1606 P. externa 1 N going like hell 1608 Storm Pet 1 [illegible] 1615 distant stop for station WEATHER: 0630 Barom [illegible] (14.6) salin: 34.72 wind 12 knt from NE Sea Temp: 26.2 wct Temp: 74.8°F dry Temp: 78.8°F CirroStratus 20% Thermal depth 0430 50 meters, enola ca 150 Weather 1 Wave period 06, amount 04 ft. See resume obs. Following div. line seen? Following looked like Hanc. or wilts ? open obs.- SS 3knts South. Circled ship, landed on H2O black div. line seen: this individual had unusually prominent wing markings; had flight similar to Wilson's resume full speed. SA, circled ship & landed SI-MNH-958-e Rev. 5-66
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{ "text": "NE (045°)\n\nShip\nDirection\n\nSMITHSONIAN INSTITUTION\nDIVISION OF BIRDS\nAT SEA DAILY LOG - E\n\nOBSERVERS:\nHarrington\n\nDate 05Nov '67\nPg.# 2\n\nTIME SPECIES # DIR. BAND NO. REMARKS\n\n0950 Wedgetail\n1000 wwp\n1010 Leach's\n1811 (Face B.\nF 1013 WRSP\nLeach's\n17\n2\nTF 1015 Sooty Tern\nKermodec\n13\nNE\n1015\n1027 RTTB\n1028 JFP\n1030\n1220\n1245\n1307 RTTB\n1320\n1335 WRSP\n1355 Leach's\nWRSP\n2\n1\nN\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n [TRANSCRIPTION_TRUNCATED_DUE_TO_LOOP]
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{ "text": "Ship\nDirection\nSW\n\nSMITHSONIAN INSTITUTION\nDIVISION OF BIRDS\nAT SEA DAILY LOG - E\n\nOBSERVERS:\n\nDate 12 November 1967\nPg.# 1\n\nTIME SPECIES # DIR. BAND NO. REMARKS\n0555 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - [TRANSCRIPTION_TRUNCATED_DUE_TO_LOOP]
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ITINERARY 16 October, 1967 1100 hours (+7 time) Depart San Diego, Calif. 07 November 2359 Arrive Manzanillo, Mexico 10 November 1100 Depart Manzanillo 03 December ca. 0200 Arrive San Diego The following report summarizes bird and mammal observations conducted aboard the R/V DAVID STARR JORDAN during EASTROPAC Monitor Cruise No. 50 from 17 October to 03 December, 1967. During this period diurnal observa- tions were maintained for 297.9 hours over 3465 nautical miles. A total of 14463 seabirds was recorded. No observations were made when the ship was "on station", and collections were restricted to times when they would not interfere with primary objectives of the cruise. In this report the cruise track (see map one) has been divided into water-type areas (see map two) in order to facilitate discussion. These divisions are based primarily on oceanographic differences, but occasion- ally avian differences were used. During October and November the distribution of birds within the area covered by the monitor cruise was quite graphic, but as little summarized data are available at present, no explanations beyond very crude correlations will be attempted. However the reader is urged to compare species densities and distribution carefully, especially for tropicbirds, Wedge-tailed Shear- water, and species in the genus Pterodroma. From these distributions it appears that the cruise track transversed rather prominent ecological zones, especially in the western portions of the cruise. Additional dis- cussions pertaining to ecological factors will be included elsewhere in this report. For now it should be mentioned that few patterns of abundance were noted within a single species which could be correlated to specific oceanographic or biological data as available in crude form at the time of this report. This is not to say that such patterns did not exist, but rather is intended to suggest that they were obscured in some areas by the influence of various combinations of environmental variables as well as variable responses by different species to habitat changes. METHODS Observations were maintained from the flying bridge which afforded a 360 degree horizon and an excellent angle for identification of birds fairly close to the ship. Because I was the only P.O.B.S.P. observer a- board, it was not possible to maintain continuous binocular surveillance during all daylight periods. Thus sightings were largely of birds which could be seen with the unaided eye with binocular support only for identi- fication. Hours of observation were limited to daylight periods when the ship was underway.
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OCEAN WATER TYPES Although the writer is not well versed in oceanography, the following discussion is attempted because the effect water types have on bird dis- tribution is well known. Before any correlations are attempted a general discussion is prerequisite. Probably the most graphic water type surveyed on this cruise was the North Equatorial Countercurrent. Although I am not certain of the boundaries, some of the oceanographic data suggest that on the western leg of the cruise the north boundary was at about 14°43'N - 119°10'W. In this area there was a significant change of salinity and also the writer observed "a line of marked current activity" at about 1735 hours (local-+7) on 22 October. The southern boundary of the North Equatorial Countercurrent was also indicated by a line of marked current activity. Oceanographic data also substantiated this observation with marked salinity and temperature changes having been recorded at 03°59'N - 119°10'W. Travelling eastward and then north along 112°10'W, the southern bound- ary of the countercurrent was again visually observed as well as substant- iated by oceanographic data at 04°53'N. The northern boundary was not visually observed, and oceanographic data as available at present do not make the boundary unquestionably clear. However there were rather marked salinity and temperature changes near 15°N - 118°W. Whether this was the countercurrent boundary or some other water type is not clear. Avian changes, however, suggest that it may have been the boundary and it is considered as such in this report. On the remainder of the cruise the countercurrent boundaries were not visually observed. Oceanographic data suggested boundaries near 11°N and between 1° and 2°N along 105°10'W longitude, and was somewhat confused along 098°W. These unclear definitions in the eastern portions of the survey area are not surprising as it is near the terminus of the North Equatorial Countercurrent and is also near the area where the eastward moving equatorial undercurrent breaks and diverts in the vicinity of the Galapagos Islands. Thus with the data available to the writer at present the water type boundaries in the eastern areas should remain indefinite. COASTAL WATERS The survey area along the Mexican coast between Manzanillo and Acapulco is separated for discussion purposes only, and is probably incorrectly con- sidered a single water type. The oceanographic data collected on three five-hundred mile transects through the area are confusing and suggest several influences with upwelling probably being major. Along the central and northern Baja coastline the California Current is without doubt the major influence. Although few oceanographic data were collected, the junction of the Current and southern water appears to have been off Magdalena Bay where high seas, high winds, and spectacular numbers of animals were recorded.
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At the mouth of the Gulf of California no oceanographic data were collected. However, as the Gulf was approached from the southeast a distinct current line was crossed. This suggests that the vessel was entering a different water-type, which is a logical presumption in light of the known oceanography. Off Cape San Lucas another water type was probably present, but no signs of a division were observed by the writer beyond slim suggestion by bird distribution. The last major area of water being considered is that in the southern extremes of the survey area south of the North Equatorial Countercurrent. The water was characterized by high salinities and low temperatures and was probably the northern portion of the westward flowing South Equatorial Current. One other portion of the survey area will be considered as another water type although insufficient oceanographic data were collected to justify such a separation. However, on the basis of bird distribution such a division seems reasonable. Thus the section of the western leg of the cruise between 15° and 28°N will be treated as a separate water type. As mentioned above, the oceanographic characters of a water type are either directly or indirectly major factors in delineating species and density distribution of birds. Whether this holds true for migrants as well as resident birds will not be a concern in this report as there was little suggestion of migratory travel throughout the cruise. Thus it is felt that a correlation of distributions and water types would reflect the uninfluenced effect that water types have on the presumed resident birds. The divisions as established in the above discussions are shown in map 2; maps 3 and 4 show surface temperatures and salinities for additional reference, and table 2 shows the species breakdown for each area. Table 3 shows species habitat (water type) preference in a simplified form. SPECIES ACCOUNTS (Note: Only species for which there is additional information are listed below. See Tables for total avifauna.) Procellaria sp. A single bird which was probably a Black Petrel (Procellaria parkinsoni) "...bird all dark, light-colored bill (which was fairly short); body shape much like an albatross, wings shaped like an albatross. Flight was very distinctive,...frequent twisting and turning, a rapid flight; smaller than a Black-footed Albatross, but (slightly) larger than a Pink-footed Shearwater; tail was quite short." An accompanying drawing of the underwing shows that it was all dark with a lighter area on the ventral tip.
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Wedge-tailed Shearwater (Puffinus pacificus) 4 light and 1 dark phase collected The distribution of this species was quite interesting, especially when compared to that of the Pterodroma (see maps 5 and 8). Perhaps more interesting, however, are the changes in color phase ratios on tracks transversed by the R/V UNDAUNTED in August-September and the R/V DSJ in October-November. In late August dark phase birds comprised 96 percent (N=132) of the birds along 105°W and 85 percent along 98°W. In November the light phase population was predominant by 8.5:1 in equivalent sections of the track. This change of color phase ratio clearly suggests that there are two Wedgetail populations in the Eastropac area at some times of the year, and that one of these populations had left the area by October-November. In other Eastropac reports it has been suggested that many of the Wedgetails in the survey area are from the Hawaiian group; the information from this cruise further substantiates this hypothesis. Slight additional suggestion may be found from the few specimens of Wedgetails which were collected during this cruise. As the Hawaiian population is now breeding we would expect that any remaining in the eastern area during October-November would be subadults or nonbreeding birds. This is what was noted in the five specimens collected. The distribution of Wedgetails in the survey area (see tables 2 and 3) suggested that the October-November population favored the eastern portion of the North Equatorial Countercurrent with none being recorded below the southern boundary and only one north of the boundary in pelagic portions of the track. A few additional birds were seen within 500 miles of the Mexican coast. Pale-footed Shearwater (Puffinus creutopus) Pale-feet were rarely seen in pelagic waters. Along the coast they were seen uncommonly except off northern Baja where they were common. Christmas Shearwater (Puffinus nativitatis) A single bird travelling southwest was seen at the edge of a rain squall on the fourteenth of November, along 98°W. Common Shearwater (Puffinus puffinus) What were believed to have been two subspecies were seen during the course of the cruise. Most abundant was P.p. opisthalemas which was seen by the thousands off the northern Baja coast. What was believed to have been another subspecies was seen along the Mexican coast and at the mouth of the Gulf of California. It was the writer's impression that these birds were much blacker on the back than their northern counterparts. Farther to sea the Common Shearwater was rare. Their subspecific identification should remain open to question as it is possible some could be Newell's Shearwater from the Hawaiian Islands.
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Sooty and Slender-billed Shearwater (Puffinus griseus and P. tenuirostris) Because these two species are easily confused all sightings were called Sooty/Slenderbills. However, of the few birds that were seen well, none were Slenderbills. Most of the sightings (excepting those off the Baja Peninsula) were of birds gravitating towards the southeast. Juan Fernandez Petrel (Pterodroma externa) 6 collected All of the birds which were seen well were identified as the sub- species externa and the writer is convinced that there were no cervicalis in the area. The distribution was somewhat confusing, but increasing abundance from east to west was evident, especially in the countercurrent area where the highest densities for the cruise were recorded. Although Wedge-tailed Shearwaters were present and most abundant in the same area, a day to day comparison of ratios demonstrates that there was little cor- relation of numbers between the two species. That the two have different ecological requirements may also be inferred from a comparison of the eastern distribution within the survey area. Whereas Wedge-tails were found along the easternmost portions of the track, no P. externa were seen east of 105° west longitude. Further suggestion of ecological re- quirements may be inferred from the north-south distribution of the two species. Virtually no Wedge-tails were seen south of the southern border of the North Equatorial Countercurrent, whereas Juan Fernandez Petrels were seen as far south as the cruise track went. Six specimens of Juan Fernandez Petrels were collected along the westernmost portion of the cruise. All were of nonbreeding age, had heavy body molt, and were in a light fat condition. Cook's Petrel (Pterodroma cookii) A few birds of this species were seen about three hundred miles west of Baja in mid-October. Although only a few were seen, there was some suggestion that they were in southeasterly migration. Black-winged Petrel (Pterodroma hypoleuca nigripennis) A total of 34 birds was identified as this subspecies between five and fifteen degrees north latitude on the western leg of the cruise. There was no suggestion that they were migrating. It is interesting and perhaps significant that the range met but did not overlap the range of the White-winged Petrel (P. leucoptera) recorded on the survey. It is also significant (?) that no hypoleucans of the subspecies hypoleuca were recorded on this cruise; they were said to have been present in approximately the same area in August-September.
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White-winged Petrel (Pterodroma leucoptera) Although never a common bird on this cruise, White-wings were regularly sighted on the western half of the track area below the north boundary of the North Equatorial Countercurrent. What were believed to have been two different subspecies were recorded. Most common was P. l. masafuera(?) which was seen regularly in the eastern three quarters of the Countercurrent as well as in waters to the south of the current. What were believed to have been P.l. brevipes were seen on the western leg, north of the range of masafuera. Although the writer is not certain of the subspecific assignment the two forms were given, he is sure that no less than two subspecies were seen. The ones to the south were surprisingly uniform in appearance. The birds were characterized by a very dark head and nape, with a markedly lighter back which had a very prominent "W" pattern. The underwings were white with thick black borders. Most striking however, was an incomplete collar down the side of the upper breast which was almost black. The leucopterans to the north had an interrupted gray collar with indistinct margins; they also had a thinner black border on the underwings than their southern counterparts. Because there is considerable confusion in the writer's mind as to where which forms of leucoptera breed, the subspecies assigned to the above forms may be in error. I am quite certain that the few I called brevipes were in fact brevipes, but the subspecific identifications of the southern form should remain open to question. Phoenix Petrel and Tahitian Petrel (Pterodroma alba and P. rostrata) Because these two species may be confused, all sightings were recorded as Phoenix/Tahitian Petrels. However, the writer feels that both species were present in the area with the Phoenix being the more common of the two. Neither bird was common, however. Virtually all of the sightings were between 10° and 5° north latitude. The habitat preference appeared to be similar to that of the Juan Fernandez Petrels. Kermadec Petrel (Pterodroma neglecta) Compared to the August-September cruises there were very few birds of this species present in the EASTROPAC area. Both light and dark phase birds were seen. Murphy's Petrel (Pterodroma ultima) There was no bird seen on this cruise which could positively be identified as this species. However, a single bird seen sitting with about 50 storm petrels on 23 October was suspected to be a Murphy's Petrel. Harcourt's Storm Petrel (Oceanodroma castro) A total of 39 birds believed to have been this species was seen throughout the cruise. However, because of the difficulty in identifying the dark storm petrels, there were probably many more which were recorded only as white-rumped storm petrels. The distribution of those which were identified
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suggests that low numbers may be found north of the southern boundary of the North Equatorial Countercurrent, and very few to the south. Harcourt's were also very scarce within 400 miles of the coast. Leach's Storm Petrel (Oceanodroma leucorhoa) 1 collected This was the most widely distributed species on the cruise; they were seen commonly in virtually all areas except close to shore. The white-rumped forms were the only color phase throughout the cruise except near Guadalupe Island where dark-rumped forms were seen regularly. The distribution of Leach's was irregular although widespread. Gen- erally it was suspected that over most of the survey the birds were residents. However, between 15° and 25° North on the western track there was some suggestion that many of the sightings were of migrants. Small flocks were seen frequently, and there was also slight suggestion of a southeasterly movement. Galapagos Storm Petrel (Oceanodroma tethys) This was the most easily identified white-rumped storm petrel seen on the cruise. Thus it is felt that most which were seen were recorded to species and that few of those birds recorded as "white-rumped storm petrels" were of this species. The distribution of O. tethys appeared to be restricted to areas near the Galapagos Islands; only a few were seen more than 500 miles to the west. Although crude allowances were made, it is possible that the densities recorded in tables of this report may be somewhat inaccurate as it was not possible to determine how long individuals followed the ship. Regardless, the observations did indicate that the species was more common to the west than to the northwest or southwest of the breeding islands. Black Storm Petrel (Loomelania melania) During October-November this was found to be a coastal species within the cruise area. All sightings were south of central Baja Peninsula. Least Storm Petrel (Halocyptena microsoma) What few birds were seen were within the range of the Black Storm Petrel. Loon (Gavia sp.) A single unidentified loon was seen off Northern Baja on 2 December; it was being harassed by a Pale-footed Shearwater. Brown Pelican (Pelicanus occidentalis) This species was seen only off Northern Baja and in the harbour at Manzanillo.
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Red-billed Tropicbird (Phaethon aethereus) Red-bills were never recorded commonly on the cruise. The distribution was irregular and seemed to be influenced by the proximity of land as well as by water type. Sightings were most frequent in the coastal waters with all the remaining being south of the equator west of the Galapagos. Red-tailed Tropicbird (Phaethon rubricauda) 2 collected All sightings were in the western half of the survey area with highest densities between five and fifteen degrees North. Virtually every bird seen was a subadult (based on bill and plumage characters) and only one immature (less than one year old) was seen. No Red-tails were seen along 105 West where several were seen in August. Blue-faced Booby (Sula dactylatra) The observations on this cruise suggested that this is a land-oriented species in the EASTROPAC area as all of the sightings were within 400 miles of the coast. Brown Booby (Sula leucogaster) Apparently a rigidly land-oriented species at this season. At the peripheral portions of the species range both immatures and subadults were more common than adults. Along the coast the adults were abundant with many sightings of flocks flying out from the shore in the early morning hours. Red-footed Booby (Sula sula) Like the other boobies, the Red-feet also appeared to be a land- oriented species. Highest numbers were recorded in the eastern half of the cruise area, and most were north of 10°. Frigatebirds (Fregata sp.) Recorded only in low numbers throughout the cruise except on 22 Nov- ember when over 30 were seen in a large mixed flock just before sunset. Unfortunately I was not able to identify any of the frigates to species. Phalaropes (Phalaropus fulicarius and Lobipes lobatus) Both Red and Northern Phalaropes were seen commonly along the southern coastal portions of the cruise. In pelagic portions both species were recorded only rarely. Jaegers (Stercorarius pomarinus S. parasiticus, and S. longicaudus) All three species of jaeger were identified with Pomarine being the most common by a large margin. As is usually the case with jaegers, the distribution indicated a preference for coastal waters with highest occurrence in areas where overall bird density was high.
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Western Gull (Larus occidentalis) Adults and immatures were observed along the east shore of Guadalupe Island and off the north coast of Baja California. Herring and California Gulls (Larus argentatus and L. Californicus) Immatures were seen along the Baja coast as far south as Cape San Lucas; adults were seen only to the north of Magdalena Bay. Bonaparte's Gulls (Larus philadelphia) Seen almost exclusively off Magdalena Bay on 1 December. During the early morning immatures were seen in a ratio of 2 to 3 adults (N=29), but during the late morning and afternoon no immatures were seen among the 56 for which age was observed. Black-legged Kittiwake (Rissa tridactyla) Seen in low numbers off Magdalena Bay. Sabine's Gull (Xema sabini) Seen most commonly on 1 December off Magdalena Bay, but also seen along the coast as far south as Acapulco. Sooty Tern (Sterna fuscata) In terms of numbers this was the second most abundant species ident- ified on the cruise. However, most of the birds in the tally were in flocks, and the number of sightings was small. Both adults and immatures were seen in a 400 mile wide band between Clipperton and the Galapagos Islands, but no immatures were recorded on other portions of the cruise. The Sooties off Manzanillo and at the mouth of the Gulf of California were in fresh plumage with long tail feathers suggesting that they were nonbreeding birds. Elsewhere no adults were seen well enough to determine the plumage condition. ADDITIONAL BIRD OBSERVATIONS A distant flock of ca. 5000 birds believed to have been storm petrels was seen off Magdalena Bay, Baja Peninsula. Because this sighting was unique and its reliability questionable, it has not been included in this report excepting in the overall tally of seabirds in the introduction, and in table 1. Landbirds Landbirds were seen frequently on some parts of the cruise. A summary may be found in table 4. MAMMAL SIGHTINGS Mammals were scarce during the cruise; a summary of sightings is
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TABLE 2. Water-type Breakdown of Species Distribution on EAC 26 Eastropac 50. Section A* Section B1 Section B2 Section B3 Section B4 Overall Average Sections B1 - B4 Loon sp. Procellaria sp. Dark-rumped Petrel Pterodroma externa 5 .014 292 1.12 196 .563 7 .036 0 1 .001 Phoenix/Tahitian Petrel 3 .015 1 .003 1 .005 2 .009 7 .007 Kermadec Petrel 1 .003 0 1 .003 1 .005 2 .009 4 .004 Murphy's Petrel 1 .004 4 .015 6 .017 9 .046 17 .081 1 .001 P. leucoptera brevipes 5 .005 P. leucoptera masafuerae 32 .032 P. hypoleuca 1 .003 33 .127 1 .003 1 .003 5 .024 33 .033 P. cookii 3 .011 121 .465 44 .126 45 .228 264 1.251 6 .006 Wedge-tailed Shearwater 1 .003 1 .003 2 .010 1 .005 7 .007 Pale-footed Shearwater 1 .005 1 .001 Pink-footed Shearwater 1 .004 3 .009 2 .010 1 .005 6 .006 Sooty/Slenderbill 1 .004 1 .005 1 .005 1 .005 6 .006 Christmas Shearwater 1 .004 4 .012 5 .025 2 .009 21 .021 Common (=Manx) Shearwater 7 .020 10 .038 4 .012 2 .009 131 .129 Harcourt's Storm Petrel 46 .133 51 .196 21 .060 22 .112 37 .175 246 .243 Leach's Storm Petrel 39 .113 119 .458 78 .227 28 .142 21 .100 White-rumped Storm Petrel (unidentified) 23 .109 23 .023 Galapagos Storm Petrel Black Storm Petrel Least Storm Petrel Red-billed Tropicbird Red-tailed Tropicbird 3 .011 7 .027 14 .040 21 .021 Brown Pelican 1 .003 4 .012 1 .005 2 .009 7 .007 Blue-faced Booby Brown Booby Red-footed Booby 1 .003 1 .003 2 .010 33 .156 36 .036 Frigatebird sp. 1 .003 2 .006 1 .005 3 .003 Red Phalarope Northern Phalarope 1 .003 7 .036 11 .052 18 .018 Phalarope sp. 1 .003 Pomarine Jaeger 1 .003 Parasitic Jaeger 1 .004 1 .003 2 .010 2 .002 Long-tailed Jaeger 2 .008 3 .009 2 .010 7 .007 Jaeger sp. Gull sp. * see map 2
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Table 3: Figures Showing Relative Abundance of Birds within Species Groups in Different Water Types * Water Type average Size of A B1 B2 B3 B4 B C1-3 C4-6 D1-4 E F G sample Pterodroma externa + 5 2 1 0 2 + 0 0 0 0 0 0 562 Phoenix/Tahitian Petrel 0 4 1 1 2 2 1 0 0 0 0 0 0 9 Kermadeç Petrel 1 0 1 2 3 2 0 0 0 0 0 0 0 6 Pterod. leucoptera (a) 0 7 1 0 2 2 1 0 0 0 0 0 0 5 Pterod. leucoptera (b) 0 0 1 2 4 1 2 + 0 0 0 0 0 60 Pterod. hypoleuca + 8 0 0 0 2 0 0 0 0 0 0 0 34 Pterod. cookii 3 0 1 0 5 1 0 0 0 0 0 0 0 9 Wedge-tail Shearwater + 2 + 1 5 2 0 0 + 0 0 0 0 522 Pale-foot Shearwater 0 0 + 0 + + 0 0 + 0 0 9 0 173 Sooty/Slenderbill 0 + + + + + 0 0 + 0 0 8 0 97 Common Shearwater 0 + 0 0 + + + 0 0 + 2 0 8 3710 Harcourt's Petrel 1 3 1 2 1 1 + 0 1 + 0 0 0 39 Leach's Petrel 1 2 + 1 2 1 + 1 + 0 0 + 0 317 WRSP (Unidentified) 1 3 1 1 1 1 + 1 + 0 0 + 0 465 Galapagos storm pet. 0 0 0 0 5 1 4 0 0 0 0 0 0 74 Red-billed Tropicbird 0 0 0 0 0 0 2 4 5 0 0 0 0 6 Red-tailed Tropicbird 1 3 4 0 0 2 + 0 0 0 0 0 0 26 Blue-face Booby + 0 1 + 1 1 0 0 7 0 0 0 0 49 Brown Booby 0 0 0 0 0 0 0 0 6 4 0 0 0 212 Red-foot Booby + 0 0 0 3 1 0 0 6 0 0 0 0 50 Frigatebird sp. 0 0 + + 5 1 0 + + + 2 + 0 47 Pomarine Jaeger 1 0 0 1 1 + + 0 2 0 0 6 0 167 Parasitic Jaeger 0 0 0 0 0 0 3 0 3 0 0 0 3 3 Long-tail Jaeger 0 2 2 0 0 1 0 1 0 0 0 4 0 6 Jaeger sp. 0 1 1 1 0 1 1 0 4 0 0 1 0 32 Sooty Tern 0 + 1 2 3 1 + + 1 2 0 0 0 814 * NOTE: Excepting the last column, the numbers in this table in no way reflect the actual number of birds recorded. Instead they suggest the relative abundance within a species seen from section to section regardless of the order of magnitude. # The sections used in this table are the same as for table 2. (see map 2) + Indicates species present in very low numbers compared to other areas. In areas where none were seen a "0" was recorded.
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APPENDIX C. Daily Abundance of Flocks (excludes phalaropes) 18 October "Puddle Ducks" 17 Travelling 19 October 0920 Leach's Storm Petrel 5 Sitting on water 1045 Leach's Storm Petrel 5 Sitting on water 22 October 1735 White-rumped Storm Petrel 13 Feeding on line of currents 23 October 0950 Leach's Storm Petrel 5 On water, flushed to southeast 1010 Mixed feeding flock (6 species, 12 stenella) 28 1120 Pintail 25 South 1231 Pterodroma externa 6 Feeding 1235 Shearwater/Petrel 8 At edge of rain squall 1346 Mixed (4 species) 16 Feeding 1350 Storm petrels 6 Feeding ? 1459 Storm petrels 8 On water 1515 Storm petrels and 1 Murphy's Petrel(?) 56 On water with "small"slick 24 October sunrise Mixed (1) 285 Feeding near buoy 25 October 1526 Mixed 28 Feeding 26 October 0952 White-rumped Storm Petrel 10 Feeding along current line 1505 White-rumped Storm Petrel 6 No description 02 November 0817 Mixed 87 Feeding 0830 Mixed 152 Feeding 0835 Juan Fernandez Petrel 6 Feeding 0837 Juan Fernandez Petrel 10 Feeding 0845 Juan Fernandez Petrel 5 On water 0850 Juan Fernandez Petrel 17 On water 0917 Mixed 11 Feeding 1025 Mixed 72 Feeding 03 November 1350 Mixed 9 Sitting on water 05 November 0730 Mixed 102 Feeding 0746 White-rumped Storm Petrel 8 On water 0933 Mixed 7 Feeding 1013 White-rumped Storm Petrel 19 Sitting on water 1015 Sooty Tern (adult) 13 Travelling 1358 White-rumped Storm Petrel 10 Travelling with ship 07 November 1330 Mixed 22 Feeding 1411 Mixed 21 Feeding 1419 Mixed 23 Feeding 1422 Mixed 30 Feeding 1510 Sooty Terns 8 Feeding 1528 Sooty Terns 28 Feeding 1547 Mixed 80 Feeding 12 November 1550 Sooty Tern & Jaeger 10 Feeding 1000 White-rumped Storm Petrel 5 Feeding