10 



PROCEEDINGS OF THE NATIONAL MUSEUM 



Wind direction 44-45 

 Wind speed 46-47 

 Barometer 48-49 

 Weather conditions 50-51 

 State of sea 52 

 Visibility 53 

 Surface oxygen 54-56 

 Surface phosphate 57-59 



Moon age 60 

 Cloud cover 61 

 Air temperature 62-64 

 Relative humidity 65-66 

 Wave direction 67-68 

 [Columns 69-80 were not utilized on 

 the environment cards.] 



Thermocline depth was recorded in meters. Water temperatures 

 at the surface and at 10 meters and air temperature were given to the 

 nearest .1° C. Surface salinity was recorded in parts per thousand, 

 omitting the initial 3 for any value. Wind and wave direction were 

 coded in the same manner as direction of ship's movement, column 43 

 on the sighting card. The code for weather conditions is given in 

 table 3 and those for state of sea, visibility, and cloud cover, in table 4. 

 Wind speed was recorded in knots. Barometric pressure was recorded 

 as the last two digits of a millibar reading, e.g., 1015 millibars was 

 coded as 15. Surface oxygen was recorded in milliliters per liter to 

 the nearest .01 and surface phosphate in microgram atoms per liter 

 to the nearest .01. Relative humidity was expressed in whole percent. 

 Moon age was not recorded for this study but a BCF code is given in 

 table 4. 



Day deck. — The day card includes information pertaining to all 

 sighting and environment cards for one day and is concerned mainly 

 with positions, distances, and times. From this card, in combination 

 with the sighting cards from the entire day, the computer calculates 

 daily density figures in terms of birds per hour and birds per linear 

 mile. Through the use of such density figures, we can make direct 

 comparison between bird density in different areas of the ocean and 

 from day to day, month to month, and even year to year within the 

 same area. It is important to be able to express density as a factor 

 both of time and distance because the two are not correlated neces- 

 sarily on a cruise with periodic stops such as the BCF Cromwell 

 cruises. The day cards, code 98 in columns 1-2, are linked to the other 

 two decks through information on the ship's name 3-5, cruise number 

 6-9, and date 10-15. In addition, the day card contains the following 

 information coded on the blue intermediate sheets (fig. 3) : 



Diurnal hours of observation 16-18 

 Diurnal miles of observation 19-21 

 Nocturnal hours of observation 22-24 

 Nocturnal miles of observation 25-27 

 Position at midday 28-36 

 Position at sunrise 37-44 

 Position at sunset 45-52 



Local time of sunrise 53-56 

 Local time of sunset 57-60 

 Number of observers on each watch 61 

 Quantitative plankton analysis 62-64 

 [Columns 65-80 were not utilized on 

 the day cards.] 



