WHALE MARKING II 37 



(3) February (Plate XVII). This is the best Fin whale month in this region, with 43 1 whales marked. 

 These are spread out in a rather scattered manner from 35 to 105 ' E, but between 20 and 35° E quite 

 significant numbers were marked in 1935 and 1937. The most easterly whales were marked in 1936. 

 It is to be noted that very few Fin whales were marked in January and February between 60 and 

 90° E, and almost all these were in 1937. This region was traversed several times in February, and 

 in good weather, by the 'William Scoresby', but very few whales of any kind were seen. 



(4) March (Plate XVIII). As mentioned above March was spent in the western part of the area 

 preparatory to turning homewards. Moderate numbers (302) have been marked between 08° E and 

 56° E with the major number between 19 and 48° E — a rather similar distribution to February. All 

 whales east of 20° E were marked in 1936, and those to the west of this meridian in 1935 and 1937. 



III. HUMPBACK WHALES 



(a) Western Area 



The Humpback whale is now a rare animal in waters around South Georgia and the number marked 

 in the vicinity of the island is insignificant. 



(i) December (Plate XIX). A very few whales were marked by the 'William Scoresby' in 1937 on 

 the easterly cruise. 



(2) February (Plate XIX). Early in the month in 1938 when the 'William Scoresby 'was oflF Adelaide 

 Island a small number of Humpbacks were met and some marked. These may be the depleted 

 descendants of the large numbers of Humpbacks which early in the century frequented the channels 

 of the South Shetland and Palmer Archipelago, and which probably make their winter migration to the 

 west coast of South America. 



(3) March (Plate XIX). A very few were marked in 1937 about 10° E. 



(b) Eastern Area 



(i) December (Plate XX). A few Humpbacks were marked in 1934, 1935 and 1936 between 24 

 and 34° E when the ship arrived on the grounds, and a few in 1934 about 95° E. 



(2) January (Plate XXI). This was the best month for Humpbacks, 265 having been marked ; these 

 were nearly all between 85 and 98° E, and were mostly marked in 1937 with a smaller number in 1936. 



(3) February (Plate XXII). Fewer were marked in this month (107)— almost all in 1936 on the 

 easterly grounds between 87 and 99° E. 



The Humpback whale keeps to much more definite areas and to more definite routes of migration 

 than Fin and Blue whales, and the distribution of marked Humpbacks demonstrates distinct division 

 into an eastern and a western group. These points have been well proved by the recovery of marks 

 (Rayner, 1940). Humpback whales are more numerous on the eastern grounds around 95° E than in 

 the western area of concentration (about 20-40" E), but they are, to all intents, absent between these 

 two areas. No Humpback has been marked between 60 and 70" E and virtually none between 

 40 and 80° E. This separation of two groups largely holds good for Blue and Fin whales. 



During the whale-marking cruises of the ' William Scoresby ', three of them in the eastern and one 

 in the western area, a widespread search has been made for whales and the vessel has not remained in 

 areas of proved or reputed abundance. It can, therefore, be accepted that the regions of concentration 

 or scarcity of marked whales, seen in Plates V to XXII, do in fact represent in a considerable degree 

 the concentrations or scarcities of the actual population of whales during the time of these cruises. On 



