EAC 5, Shearwater, March 1967
Page 276
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Transcription
be found in table 1. An additional 14.5 of nocturnal survey were conducted (see table 5.) Weather data during this survey were recorded on appropriate forms and ADP sheets. In general, light winds and seas predom- inated; a high pressure system in the area was a major influence. Thus, in general, observation conditions were quite similar to those on the last EAC cruise, and hence the two can be reasonably compared. Also diurnal survey was conducted in approximately the same areas on both cruises thus allowing further compara- bility. But, as will be discussed later, there were major differ- ences in the populations found. Thirty bathothermographs were taken over about 3/5 of the grid track at four hour intervals; a damaged cable prevented drops over the last portion. Flocking With the exception of a few groups of storm petrels and Red phalaropes, flocking activity was not observed during this survey. Flocking in the above species will be discussed in the species accounts. Food Sources Over previous EAC cruises only one school of feed-fish has been noted. During this survey numerous schools of small fish were frequently noted at night over the western extreme of the southern two thirds of the grid. None were seen during daylight hours. It would seem likely that such an abundance would attract fish-feeding birds; but such did not seem to be the case. In fact, fewer fish- feeding species were noted than on any of the previous surveys, little doubt due to the fact that they have migrated northward.