FISHERY BULLETIN: VOL. 83, NO. 3 



Figure 1. -The Fish Harbour region on the east coast of Deer Island region, New Brunswick, Canada (see inset). Legend: Straight solid lines 

 indicate approximate limits of study area. Stipple indicates shallow shelf area (low water mark to 5 m); widely spaced vertical lines indicate 

 areas of relatively gentle slope; narrowly spaced bars indicate steep scarps or slopes terminating in cliffs and the white areas (other than 

 within island boundaries) are relatively deep basins and channels. Broken line shows regular track of boat with watch-stations 1 and 2. Place 

 names are those used in the text. Scale = 1 km. 



5.6-8.3 m (mean about 6.3 m) (Forrester 1960). 

 Water turbidity is high (Secchi disk reading in July- 

 August about 2 m). Most tidal flow from the area is 

 by the northern end of Simpson's Passage. Salinities 

 in the whole Quoddy region (Trites 1962) range from 

 29.57oo (March-May) to 32.3%o (September). Lower 

 salinities in shallow inshore waters occur after heavy 

 rain and may last for several days. While some year- 

 to-year changes in mean surface temperature were 

 recorded (Trites 1962, fig. 11), one of the most com- 

 plete series (for 1978) provides a typical sequence of 

 the relative changes from spring to autumn. Late 

 May-early June surface temperatures ranged from 

 6.0° to 7.1°C, mid-July from 8.4° to 9.6°C, and mid- 

 August-early September from 10° to 11.2°C. By 

 early December the waters were 7°C again. Peak 

 summer values of 11.3°-14.5°C were only obtained 

 in mid-August at the head of Lords Cove in shallow 

 water (< 5 m). At any given time surface tempera- 

 tures were 0.5°-1.0°C warmer than those at 12 m 

 despite the tidal mixing which obviously occurred. A 



general pattern of temperature profiles could be 

 recognized in midsummer: The inner (western) part 

 of Fish Harbour was vertically well-mixed through- 

 out, but a rather steep horizontal gradient of about 

 1.0 °C was maintained at all depths on the outer 

 margin of this zone. In the central region (near Fish 

 Island) the direction of water movement showed up 

 to 90° variation at different depths at any given time 

 of rapid tidal flow. The outer parts of Fish Harbour, 

 and Simpson's Passage, tended to be well-mixed ver- 

 tically, but were always about 0.5° cooler at the sur- 

 face on the ebb. North of Adam Island there was a 

 shift from horizonal gradients on flood to vertical 

 gradients on the ebb. The inshore water is probably 

 "trapped" in the bight of the harbor, i.e., with an ex- 

 tended residency time, while movement of water in 

 and out the northern and southern entrances prob- 

 ably creates some mixing in the outer and central 

 part of Fish Harbour. More detail of the static and 

 dynamic characteristics of the study area and adja- 

 cent regions is provided by Smith et al. (1984). 



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