MACDONALD ET AL.: FISH ASSEMBLAGES AND THEIR SEASONAL MOVEMENTS 



Table 1.— Physical and chemical characteristics and sampling history of stations in the Bay 

 of Fundy and Passamaquoddy Bay. Gear: ST = shrimp trawl; S = seine; GN = gill 

 net. Bottom type: M = mud; Sa = sand; Rk = gravel or rock. 



recorded for most sampling sites (Table 1). Bottom 

 temperature and salinity data inside and outside 

 Passamaquoddy Bay came from routine monthly 

 sampling by the Department of Fisheries and Oceans 

 at a site opposite the Biological Station (near Station 

 A) and at "Prince 5" 3.2 km south of Bliss Islands in 

 the Bay of Fundy (near station B). Temperatures at 

 deep stations were taken with a reversing ther- 

 mometer attached to a Nansen bottle and at shallow 

 stations with a hand thermometer. Salinities were 

 determined with a laboratory salinometer from sam- 

 ples collected in the field. Substrate samples at deep 

 stations were obtained with a PONAR grab. At 

 shallow stations, substrate type was assessed 

 visually. 



Fishes were identified using Leim and Scott (1966) 

 with the exception of red and white hake and redfish, 

 which were determined by using Musick (1973) and 

 Ni (1982), respectively. Because we were unaware of 

 the problem of distinguishing between young Raja 

 ocellata and R. erinacea (McEachran and Musick 

 1973), these determinations may be incorrect. 



Coefficients of community were calculated using 

 the formula: 



X 100 



A + B-C 



where C = number of common species, A = number 

 in assemblage 1, and B = number in assemblage 2 

 (Jaccard 1932; Kontkanen 1957). An index that com- 

 pared presence and absence of species at each sta- 

 tion (binary data) was used because species 

 abundances among stations were not comparable 

 due to different gear used. 



RESULTS AND DISCUSSION 



Station Environmental 

 Characteristics 



Temperature and salinity at stations A and B (Fig. 

 2) followed the typical, yearly cycle of a cold tem- 

 perate sea (Fig. 3). Annual temperature range in the 

 Bay of Fundy was less than in Passamaquoddy Bay. 

 Summer temperatures at inshore sites were simlar to 

 offshore sites with the exception of higher tem- 

 peratures at some estuary stations (i.e., 1 and 2) 

 (Table 1). Two notable variations occurred: The 

 early months of 1977 and August 1978 were abnor- 

 mally warm, particularly at station A ( J. Hull 5 ); and 

 throughout the study period there was a generalized 

 cooling trend. 



Salinities were highest in late summer through the 

 fall and lowest in spring at both sites. At all times of 

 year, salinities were higher in Bay of Fundy (station 

 B) than at station A (Fig. 2). Inshore sites had 

 salinities of 1-2 ppt less than station B, and salinities 

 at estuarine sites were as low as 2 1 .0 ppt during sum- 

 mer (Table 1). 



Substrates of most sites were composed of sand 

 and/or mud (Table 1). Station A had the steepest 

 slope, about 2: 100 m. Slopes at stations B and C were 

 0.4:100 and 0.6:100 m, respectively. Slopes at coastal 

 intertidal sites were gradual, about 1:100 m. Estuarine 

 stations (1,2, and 10) had extremely soft mud bot- 

 toms and station 2 had extensive eel grass beds. 



'Fisheries and Environmental Sciences, Department of Fisheries 

 and Oceans, Biological Station, St. Andrews, New Brunswick, 

 Canada EOG 2X0. 



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