Image from the Biodiversity Heritage Library.
Contributed by Smithsonian Institution Archives.
| www.biodiversitylibrary.org
Transcription
This report is a summary of observations and collections made by P.O.B.S.P.
personnel in the eastern Pacific Ocean from 1-10 April, 1967. Participating
observers included Brian Harrington (biologist-in-charge), Richard Heiden, and
James Lewis. Superior cooperation was received from the officers and crew of
the U.S.N.S. SHEARWATER (T-AG 177). The grid cruise track (see map 1) was
followed closely, and all positions are considered accurate within five miles
except on 4 April when they may have been slightly less accurate due to contin-
uous cloudy weather which prevented an accurate fix. One major deviation from
the nominal cruise track on 8 April near point "M" was a result of orders
directing the SHEARWATER to follow and identify a Russian fishing boat.
This report is divided into two sections; the first deals with the eastern
grid survey while the second summarizes the non-grid portion of the cruise.
EASTERN GRID SURVEY NO. 5
The eastern grid survey was conducted from 1215 hours 2 April until 1900
hours 9 April, 1967. A total of 94.8 hours of diurnal survey was conducted over
967 linear miles. A summary may be found in table 1. An additional 14 hours of
nocturnal observation were conducted and are summarized in table 5.
Weather data during this survey were recorded on appropriate forms and ADP
sheets. In general, light winds and seas predominated during the first third of
the survey, and were followed by moderate winds and seas over the remainder of the
grid trip. These conditions were similar enough to those of the previous two
surveys to make reasonable comparisons of populations between the three.
In general, the bird population data collected on this survey confirmed the
occurrence of migrational movements suspected of being under way during the
previous two surveys. These changes will be discussed in the species accounts.
Mammals comprised a very significant percentage of the total air-breathing
animals recorded on this survey. In fact, from the standpoint of numbers, they
were more common than birds by more than two to one. And as mammals are more