102 ECOLOGY AND LIFE HISTORY OF THE COMMON FROG 



in this pond. Frogs had arrived in West Totteridge, and there were 

 others at various points near by. Observations were continued on 

 some subsequent nights with very much the same results. 



The year 1933 was an early year, and the frogs generally spawned on 

 the night they entered the ponds; 1934 was a considerable contrast. 

 The winter had been dry and cold, and many of the ponds were not 

 full at the beginning of the season. Spawning was late. In this year, I 

 made observations almost every night for a month, so that the record is 

 nearly complete. I had also been lucky enough to fmd, in January, a 

 pond about three hundred yards downhill from Large Totteridge in 

 which a number of frogs were hibernating. I felt that they would not 

 spawn in that pond, but would go to Large Totteridge when the time 

 came, so I tagged two of them with paper labels on March 3rd. On 

 the afternoon of March loth, I saw no frogs in this pond except one 

 female and one juvenile. 



Migration followed the same general pattern as in 1933, but with 

 important differences. Almost the whole of the migration took place 

 before any croaking was heard, and although the frogs steadily 

 assembled in the ponds, and even gathered at the spawn sites, they 

 merely waited there, silent and inactive, night after night, as if they 

 were expecting some signal to begin their breeding activities. More- 

 over, although many of the ditches were dry, and had been so for 

 about a year, the frogs, in general, followed the same routes as when 

 they were full of water in 1933. 



The most important observations were, however, those obtained 

 from the marked frogs. The frog marked in Hibernating Pond on 

 March 3rd was found sitting on the edge of Large Totteridge on the 

 evening of March 24th, facing the pond in such a position that with 

 one jump he could have leapt into the pond. I saw the label in the light 

 of my lamp, and managed to secure him and read the number on the 

 label. No spawn had been laid in Hibernating Pond, as I expected 

 would happen, and it is practically certain that all the frogs there 

 migrated to Large Totteridge, although in this year no water from 

 this pond flowed down the ditch as it did in 1933. A frog tagged in 

 Middle Totteridge on March 12th was recovered in Large Totteridge, 

 180 yards west, on April 4th. The remarkable feature of the migra- 

 tion of this frog was that spawning did eventually take place in Middle 

 Totteridge, but was very late. The first clumps were in fact seen this 

 same evening, so it is probable that D5, the frog that made the journey. 



