74 



NOAA Technical Report NMFS 140 



NEW \ NEW s\ \ 



JERSEY •.YORK/' *> \ NEW / 



«, ^ Y \ \ HAMPSHIRE .' 



S? 0R " N. ^^CONNECT I CUT V 



V^ 



EXPLANATION 



□ <0.l - 0.9 



M l0 * " 



0.0 - 45.3 



GRAMS 

 PER SQUARE METER 



40° 



HYDROZOA 



Figure 33 



Geographic distribution of Hydrozoa; A — number of specimens per square meter of 

 bottom; B — biomass in grams per square meter of bottom. 



was only 0.9 colonies/m 2 where the temperature range 

 was small, reaching an average of 46 colonies/m 2 where 

 the temperature range was broad (Table 21; Fig. 37), a 

 marked increase in density occurred between die 12-15.9°C 

 and 1 6-19.9°C classes: in die former the average density was 

 5 colonies/m 2 ; in the latter it was 37 colonies/m 2 . 



The contribution of hydroids to the total faunal den- 

 sity was <0.5% in the middle and low-range classes but 

 was above 1% in the two high-range classes (Table 22). 



Hydroid biomass was moderate or low in all tempera- 

 ture range classes and no consistent trend in relation to 

 temperature range was evident (Tables 23, 24; Fig. 37). 



