Cape 

 Elizobeth 



Penobscot 

 Boy 



X 

 (14) 



X 

 (13) 



CENTRAL AREA 



MtDeseM (17) EASTERN AREA 



7|« so' «0 »0' JO' 10' 70* »0' 40' so' to' 10' 69* so' «0' so' to' 10' 69* M' 40' SO' 10' 10' 67' SO' 40' SO' 



Figure 1. — Zooplankton sampling stations. Gulf of Maine coastal waters, 1964. Station numbers are shown In parentheses. 



ranging fronn a half to a sixty-fourth, depend- tified to species, and the numbers of copepods 



ing on the mass of the sample, and sorted into and other zooplankters per 100m. 3 of water 



major taxonomic groups. Copepods wereiden- were calculated. 



ABUNDANCE, COMPOSITION, AND DISTRIBUTION OF ZOOPLANKTON 



Zooplankton volumes 



Comparison of mean seasonal volumes of 

 zooplankton shows that seasonal variation dif- 

 fered annong the three coastal areas. All 

 areas had their lowest volumes of zooplankton 

 in the winter; the eastern area had its zoo- 

 plankton peak in spring; the central area, in 

 fall; and the western area, in summer (fig. 2), 

 Seasonal variation was greatest in the western 

 area, where the summer high exceeded values 

 for winter, spring, and fall by a ratio of 3:1. 

 These values are considered to be minimal 



estinnates of zooplankton abundance because 

 the 0.37-mm. mesh aperture confined sampling 

 to the larger zooplankters, particularly cala- 

 noid copepods. 



The nonparametric Mann- Whitney U-test 

 (Siegel, 1956) was used to test for differences 

 between areas. Western volumes were sig- 

 nificantly higher (P < 0.05) than central or 

 eastern volumes in the spring, and higher than 

 eastern volumes in the summer (table 1). 

 Sample volumes are given for each Gulf of 

 Maine coastal area in table 2. 



