which prevailed from the 17th through the 19th were probably 

 the responsible factor. 



In view of this evident lack of both field ice and bergs, one 

 PBIG aircraft and crew was ordered to return to its home base 

 for a 2-week period on March 22. Also, both of the ice patrol 

 cutters, the Anish7iet and the Androscoggin, were placed on ex- 

 tended stand-by since it was obvious that, barring some extreme 

 development, their services would not be required this season. 



Unfavorable weather precluded further searches until March 

 30 when a flight scouted the area between 47°00' N. and 49°00' N. 

 from the coast to longitude 47°00' W., the only sighting being a 

 growler in Conception Bay, Newfoundland. 



The annual aerial survey of ice conditions in the Gulf of St. 

 Lawrence and Cabot Straits was inaugurated by the Canadian 

 Department of Transport on March 7 and reported "ice condi- 

 tions abnormally good" with an assurance of a very early opening 

 of navigation. 



Reports of about a dozen bergs between latitudes 56°00' N. 

 and 58°00' N. and longitudes 36°00' W. and 40°00' W. by the 

 U. S. C. G. Cutters Mackinac and Rockaway while enroute to and 

 from Ocean Weather Station "A", on about March 10, were prob- 

 ably the most unusual sightings of the month. Their position, 

 well southeast of southern Greenland, raises some speculation as 

 to a possible shift in the general current pattern in that locality. 

 During March, 10 flights were made. It is estimated that two 

 bergs drifted south of latitude 48°00' N. Distribution of field ice 

 and icebergs is shown graphically in figure 2. 



APRIL 

 A flight on April 1 searched along the Labrador current to 

 latitude 55°00' N. and defined the outer limits of loose strings of 

 field ice from Cape Bauld, Newfoundland, to 53°10' N., 52°10' W., 

 thence northward. The only two bergs sighted were well north 

 of latitude 53°30' N. On the 8th, it was decided to explore the 

 area well north of the usual search areas to ascertain whether any 

 ice between latitudes 53°00' N. and 56°00' N. might conceivably 

 menace shipping late in the season. When a total of only six 

 small bergs and several growlers was observed in the entire area 

 searched, there remained little doubt that the 1951 season would 

 be recorded as one of the lightest seasons since the inception of 

 Ice Patrol services. The policy of returning a PBIG aircraft to 

 its home base was therefore continued. 



On April 19 a flight was carried out to ascertain the navigability 

 of the Strait of Belle Isle and eastward along track "G" to longi- 

 tude 53°30' W. Since the northern passage was found to be par- 

 tially closed and strings of field ice were observed from the western 



