112 Thiriy-sixih Annual Meeting 



factor.s against an increase in the number of shad and perhaps 

 liave liad something lo do willi llie decrease in the number of 

 iish in the six years preceding 1907, the results in 1907 show to 

 my mind conclusively that there is something else of greater 

 importance, namely, water temperatur(\ It is a well known fact 

 that shad come into the rivc>r freely when the water temperature 

 is below 59 or 60 degrees and on examination of the records we 

 will find that since 1900 and until this year the water tempera- 

 ture of the Delaware river during the greater part of the shad 

 season has been below those figures. The source of the Delaware 

 river is supplied by water from the mountain streams of Penn- 

 sylvania, New York and northern ISTew Jersey. Beginning with 

 1900 there have been phenomenally late springs in those sec- 

 tions. There have been heavy snowfalls during the middle and 

 latter part of April and even early in May throwing vast quan- 

 tities of snow water into the Delaw^are river and so lowering the 

 temperature. In 1906, for example, the average water tempera- 

 ture in the Delaware river at Torresdale was 571/^ degrees dur- 

 ing the first half of May and for the whole month of May it was 

 only 591/^ degrees. Between the 20th of May and the first of 

 June the water temperature was a trifle over 59 degrees. In 

 Wayne and Pike counties, Pennsylvania, and the adjoining coun- 

 ties of New Jersey and New York there was a nine inch snow 

 fall during the month of May. The lakes and stiller streams of 

 Wayne county and Pike had on several occasions a quarter of an 

 inch of ice. This is from my own knowledge since I was in 

 Wayne county at that time personally directing field work. In 

 April it was less than 45 degrees for the last half. A curious 

 fact in connection with last year was that the latter part of 

 March and the first week in April the weather in the extreme 

 upper Delaware was very warm and the temperature of the 

 water went up, but the freezing and snow weather which I have 

 mentioned began on the 15th of April. Exactly the same con- 

 ditions prevailed in 1905. On the 16th of April there was 18 

 inches of snow in Wayne county. This year there was also a 

 very warm spell in ]\Iarch so that the shad began to run very 

 early and then came a very cold spell. During the month of 

 April tJie lowest water temperature was 43°. the highest 56° at 

 Torresdale with an average for the month of 49°. For the first 



