Winter Condition of Some Puget Sound Algae 



Annie May Hurd, 

 University of Washington, Seattle. 



It is still uncertain whether all marine plants have seasonal life 

 cycles; likewise whether those whose life history is influenced by the sea- 

 sons are primarily affected by change in temperature or in light intensity. 

 Davis (1911) observed the seasonal distribution of most of the algae found 

 about Woods Hole, Massachusetts. He attributes it to the great variation 

 in temperature of the water, ranging from 30° F. in February to 71° F. 

 in August, with a mean temperature below 35° for January, February and 

 March. That there is a seasonal marine flora just as there is a seasonal 

 terrestrial flora is settled for a large number of species for certain regions, 

 but with the significant difference that many forms are more luxuriant in 

 the coldest months of the year and are killed or injured with the arrival 

 of the warm season. Collins (1900) says that winter has no influence 

 whatever below the low water mark. He thinks that the plants left in 

 pools by the recessions of the tide are not inconvenienced by a freezing 

 temperature so long as they are not solidified. He found reds, browns and 

 greens growing in perfect condition under a covering of ice, mentioning 

 especially Ectocarpus and the species of Fucus. While pointing out the 

 seasonal occurrence of a number of species, he states that no generalizations 

 can be made to cover them. 



Because the climate of Puget Sound is so much milder it was thought 

 that observations of the algae growing here in midwinter might show in- 

 teresting differences between the winter flora of this coast and that of the 

 colder Atlantic waters. It was also hoped that they would throw more 

 light on the problem of seasonal distribution of marine algae in general. 

 It is unfortunate that the writer cannot extend them over a longer period 

 of time. As it is it must be emphasized that only the positive results 

 are valuable, negative results meaning nothing on account of the limited 

 number of collections. That plants were not found at a certain collection 

 may not indicate that they were not there, but probably that an unfavorable 

 time made it impossible to find them at that time. Also, since reports for 

 the deep water forms are based solely on specimens washed up on the 

 beach, it is obvious that success or failure in finding a plant might depend 



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