COMMERCIAL VALVE OF KELP-BEDS 

 SESSIONAL PAPER No. 38a 



31 



Allowing equal value for each average, these figures give an approximate average 

 of 12 pounds per plant (portions available for removal). 



Using this figure, from the data furnished in map II, I estimate that 122,760 

 tons of kelp could be obtained from this district, giving an average of 245 tons per 

 mile of coast line. 



Throughout this and succeeding surveys, measurements of the density tf the sea- 

 water holding these beds were made at frequent intervals. These and other data are 

 publish conjointly with Dr. Maclean Fraser on later pages, and liave led to the 

 conclusion that in the northern part of this district there is a noticeably smaller mean 

 salinity value than in the southern (due to influx of fresh water from the inlets of 

 the mainland and the Fraser river), the density figures being, respectively, 1-019 and 

 1-021.^ Corresponding to this, the southern portion (Haro Strait region, connected 

 to the open ocean through the strait of Juan de Fuca — see Chart I) has a much greater 

 growth of kelp, as shown in the following figures. These are calculated on the 

 assumption that the weight throughout is 12 pounds per plant. The table just given 

 shows, however, that a higher value was obtained for plants farther south, so that the 

 differences shown below are probably actually greater. 



(1) District south of Saltspring island (coast-line 60 miles), 34,140 tons of kelp, 

 being 570 tons per mile. 



(2) District north of this limit (coast-line 440 miles), 88,620 tons of kelp, being 

 200 tons per mile. 



The remaining conditions (kind of sea-bottom, tidal currents, temperature) were 

 not markedly different. Chart II clearly shows the increased growth in the southern 

 area. 



All the kelp seen in district A was Nereocystis liltJceana. 



District B. — In Howe sound there is no kelp. In Burrard inlet there is a single 

 patch of Nereocystis an acre or less in extent in Vancouver harbour; this is negli- 



1 The extremes probably show greater differences, though too few readings were taken in the 

 southern portion to lay great weight on them. Those observed were: Northern portion, 1.011 to 

 1.022: southern Dortion, 1.020 to 1.022. 



